piperidines and Myocardial-Infarction

Worldwide, there is an increasing incidence of type 2 diabetes mellitus (T2DM). Metformin is still the recommended first-line glucose-lowering drug for people with T2DM. Despite this, the effects of metformin on patient-important outcomes are still not clarified.. To assess the effects of metformin monotherapy in adults with T2DM.. We based our search on a systematic report from the Agency for Healthcare Research and Quality, and topped-up the search in CENTRAL, MEDLINE, Embase, WHO ICTRP, and ClinicalTrials.gov. Additionally, we searched the reference lists of included trials and systematic reviews, as well as health technology assessment reports and medical agencies. The date of the last search for all databases was 2 December 2019, except Embase (searched up 28 April 2017).. We included randomised controlled trials (RCTs) with at least one year's duration comparing metformin monotherapy with no intervention, behaviour changing interventions or other glucose-lowering drugs in adults with T2DM.. Two review authors read all abstracts and full-text articles/records, assessed risk of bias, and extracted outcome data independently. We resolved discrepancies by involvement of a third review author. For meta-analyses we used a random-effects model with investigation of risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the overall certainty of the evidence by using the GRADE instrument.. We included 18 RCTs with multiple study arms (N = 10,680). The percentage of participants finishing the trials was approximately 58% in all groups. Treatment duration ranged from one to 10.7 years. We judged no trials to be at low risk of bias on all 'Risk of bias' domains. The main outcomes of interest were all-cause mortality, serious adverse events (SAEs), health-related quality of life (HRQoL), cardiovascular mortality (CVM), non-fatal myocardial infarction (NFMI), non-fatal stroke (NFS), and end-stage renal disease (ESRD). Two trials compared metformin (N = 370) with insulin (N = 454). Neither trial reported on all-cause mortality, SAE, CVM, NFMI, NFS or ESRD. One trial provided information on HRQoL but did not show a substantial difference between the interventions. Seven trials compared metformin with sulphonylureas. Four trials reported on all-cause mortality: in three trials no participant died, and in the remaining trial 31/1454 participants (2.1%) in the metformin group died compared with 31/1441 participants (2.2%) in the sulphonylurea group (very low-certainty evidence). Three trials reported on SAE: in two trials no SAE occurred (186 participants); in the other trial 331/1454 participants (22.8%) in the metformin group experienced a SAE compared with 308/1441 participants (21.4%) in the sulphonylurea group (very low-certainty evidence). Two trials reported on CVM: in one trial no CVM was observed and in the other trial 4/1441 participants (0.3%) in the metformin group died of cardiovascular reasons compared with 8/1447 participants (0.6%) in the sulphonylurea group (very low-certainty evidence). Three trials reported on NFMI: in two trials no NFMI occurred, and in the other trial 21/1454 participants (1.4%) in the metformin group experienced a NFMI compared with 15/1441 participants (1.0%) in the sulphonylurea group (very low-certainty evidence). One trial reported no NFS occurred (very low-certainty evidence). No trial reported on HRQoL or ESRD. Seven trials compared metformin with thiazolidinediones (very low-certainty evidence for all outcomes). Five trials reported on all-cause mortality: in two trials no participant died; the overall RR was 0.88, 95% CI 0.55 to 1.39; P = 0.57; 5 trials; 4402 participants). Four trials reported on SAE, the RR was 0,95, 95% CI 0.84 to 1.09; P = 0.49; 3208 participants. Four trials reported on CVM, the RR was 0.71, 95% CI 0.21 to 2.39; P = 0.58; 3211 participants. Three trial reported on NFMI: in two trial. There is no clear evidence whether metformin monotherapy compared with no intervention, behaviour changing interventions or other glucose-lowering drugs influences patient-important outcomes.

Topics: Adult; Carbamates; Cardiovascular Diseases; Cause of Death; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Glucagon-Like Peptide 1; Humans; Hypoglycemic Agents; Insulin; Metformin; Myocardial Infarction; Piperidines; Quality of Life; Randomized Controlled Trials as Topic; Stroke; Sulfonylurea Compounds

Topics: Adamantane; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Humans; Incidence; Myocardial Infarction; Patient Outcome Assessment; Patient Selection; Piperidines; Research Design; Time Factors; Uracil

Peripherally acting mu-opioid receptor antagonists methylnaltrexone and alvimopan are a new class of drugs designed to reverse opioid-induced side-effects on the gastrointestinal system without compromising pain relief. This article gives an overview of the pharmacology, the efficacy, and adverse effects of these drugs. Both compounds seem to be generally well tolerated and effective for the treatment of opioid-related bowel dysfunction and postoperative ileus. Methylnaltrexone recently received approval by the US Food and Drug Administration (FDA) and the European Medicines Agency for treatment of opioid-related bowel dysfunction in patients with advanced illness. Alvimopan was recently approved by the FDA for treatment of postoperative ileus, but the use of the drug is restricted to inpatients because it has been associated with an increased rate of myocardial infarction. Further research should assess the effectiveness and safety of these drugs in clinical practice.

Topics: Analgesics, Opioid; Blood-Brain Barrier; Drug Approval; Europe; Humans; Ileus; Myocardial Infarction; Naltrexone; Narcotic Antagonists; Patient Selection; Piperidines; Postoperative Complications; Quaternary Ammonium Compounds; Research Design; Safety; United States; United States Food and Drug Administration

This article continues a series of reports on recent research developments in the field of heart failure. Key presentations made at the American College of Cardiology meeting, held in New Orleans, Louisiana, USA in March 2004 are reported. These new data have been added to existing data in cumulative meta-analyses. The WATCH study randomised 1587 patients with heart failure and left ventricular systolic dysfunction to warfarin, aspirin or clopidogrel. The study showed no difference between the effects of these agents on mortality or myocardial infarction, but hospitalisations for heart failure were higher on aspirin (22.2%) compared to warfarin (16.1%). The SCD-HeFT study showed that ICD therapy reduced all-cause mortality at 5 years by 23% in patients with predominantly NYHA class II heart failure and left ventricular systolic dysfunction, but amiodarone was ineffective. The DINAMIT study showed that ICD therapy was not beneficial in patients with left ventricular dysfunction after a recent MI, even in those with risk factors for arrhythmic death. In CASINO, levosimendan improved survival compared with dobutamine or placebo in patients with decompensated heart failure. INSPIRE showed that SPECT imaging can be used to assess risk early after acute MI safely and accurately. Rimonabant was shown to be safe and effective in treating the combined cardiovascular risk factors of smoking and obesity. An overview of new developments in cardiac resynchronisation therapy (CRT) in heart failure is also reported.

Topics: Anticoagulants; Cardiology; Clinical Trials as Topic; Death, Sudden, Cardiac; Defibrillators, Implantable; Heart Failure; Humans; Meta-Analysis as Topic; Myocardial Infarction; Pacemaker, Artificial; Piperidines; Platelet Aggregation Inhibitors; Pyrazoles; Rimonabant; United States; Warfarin

Antiplatelet drugs have an established place in the prevention of vascular events in a variety of clinical conditions, such as myocardial infarction, stroke and cardiovascular death. Both European and American guidelines recommend the use of antiplatelet drugs in patients with established coronary heart disease and other atherosclerotic disease. In high-risk patients, such as those with post-acute myocardial infarction (AMI), ischaemic stroke or transient ischaemic attack, and in patients with stable or unstable angina, peripheral arterial occlusive disease or atrial fibrillation, antiplatelet treatment may reduce the risk of a serious cardiovascular event by approximately 25%, including reduction of non-fatal myocardial infarction by 1/6, non-fatal stroke by 1/4 and cardiovascular death by 1/6. Some data indicate that antiplatelet drugs may also have a role in primary prevention. In people who are aged over 65 years, or have hypertension, hypercholesterolaemia, diabetes, obesity or familial history of myocardial infarction at young age, aspirin may reduce both cardiovascular deaths and total cardiovascular events. Aspirin has been studied and used most extensively. It may exert its beneficial effect not only by acting on platelets, but also by other mechanisms, such as preventing thromboxane A2 (TXA2)-induced vasoconstriction or reducing inflammation. Indeed, experimental data show that low-dose aspirin may suppress vascular inflammation and thereby increase the stability of atherosclerotic plaque. Moreover, in human studies, aspirin seems to be most effective in those with elevated C-reactive protein levels. Vascular events, however, do occur despite aspirin administration. This may be due to platelet activation by pathways not blocked by aspirin, intake of drugs that interfere with aspirin effect or aspirin resistance. In the CAPRIE (Clopidogrel vs. Aspirin in Patients at Risk of Ischaemic Events) study, long-term clopidogrel administered to patients with atherosclerotic vascular disease was more effective than aspirin in reducing the combined risk of ischaemic stroke, myocardial infarction or vascular death. In the setting of coronary stenting, a double regimen including aspirin and ticlopidine or clopidogrel has proved more effective in the prevention of in-stent thrombosis than aspirin alone. Chronic oral administration of the inhibitors of platelet membrane receptor GP IIb/IIIa has been largely disappointing.

Topics: Aspirin; Benzamidines; Clopidogrel; Coronary Artery Disease; Humans; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pyridines; Stroke; Ticlopidine; Treatment Outcome

To obtain more reliable and precise estimates of the effect of direct thrombin inhibitors in the management of acute coronary syndromes, including patients undergoing percutaneous coronary intervention, we undertook a meta-analysis based on individual patients' data from randomised trials comparing a direct thrombin inhibitor (hirudin, bivalirudin, argatroban, efegatran, or inogatran) with heparin.. We included trials that involved at least 200 patients. The primary efficacy outcome was death or myocardial infarction, and the primary safety outcome was major bleeding. Data from individual trials were combined by use of a modified Mantel-Haenszel method.. In 11 randomised trials, 35,970 patients were assigned up to 7 days' treatment with a direct thrombin inhibitor or heparin and followed up for at least 30 days. Compared with heparin, direct thrombin inhibitors were associated with a lower risk of death or myocardial infarction at the end of treatment (4.3% vs 5.1%; odds ratio 0.85 [95% CI 0.77-0.94]; p=0.001) and at 30 days (7.4% vs 8.2%; 0.91 [0.84-0.99]; p=0.02). This was due primarily to a reduction in myocardial infarctions (2.8% vs 3.5%; 0.80 [0.71-0.90]; p<0.001) with no apparent effect on deaths (1.9% vs 2.0%; 0.97 [0.83-1.13]; p=0.69). Subgroup analyses suggested a benefit of direct thrombin inhibitors on death or myocardial infarction in trials of both acute coronary syndromes and percutaneous coronary interventions. A reduction in death or myocardial infarction was seen with hirudin and bivalirudin but not with univalent agents. Compared with heparin, there was an increased risk of major bleeding with hirudin, but a reduction with bivalirudin. There was no excess in intracranial haemorrhage with direct thrombin inhibitors.. Direct thrombin inhibitors are superior to heparin for the prevention of death or myocardial infarction in patients with acute coronary syndromes. This information should prompt further clinical development of direct thrombin inhibitors for the management of arterial thrombosis.

Topics: Angina, Unstable; Antithrombins; Arginine; Glycine; Heparin; Hirudin Therapy; Hirudins; Humans; Myocardial Infarction; Oligopeptides; Peptide Fragments; Pipecolic Acids; Piperidines; Randomized Controlled Trials as Topic; Recombinant Proteins; Sulfonamides; Survival Rate; Thrombin

Numerous clinical trials have established the benefits of intravenous glycoprotein IIb/IIIa inhibition in the management of coronary artery disease. In contrast, the recent large-scale, placebo-controlled, randomized trials of the oral glycoprotein IIb/IIIa antagonists have failed to provide commensurate reductions in late composite ischemic end points despite potent inhibition of platelet aggregation.. The ORs for death, myocardial infarction, urgent revascularization, and major bleeding from the 4 large-scale, placebo-controlled, randomized trials with oral glycoprotein IIb/IIIa inhibitors were calculated and combined. Stratification by low-dose or high-dose therapy and the use of concurrent aspirin was also undertaken. In 33 326 patients followed for >30 days, a consistent and statistically significant increase in mortality was observed with oral glycoprotein IIb/IIIa therapy (OR, 1.37; 95% CI, 1.13 to 1.66; P:=0.001). This effect was evident regardless of aspirin coadministration and treatment with either low-dose or high-dose therapy. Although a reduction in urgent revascularization was observed with oral glycoprotein IIb/IIIa inhibition, pooled analysis favored an increase in myocardial infarction that did not demonstrate statistical significance.. Although we found a highly significant excess in mortality consistent across 4 trials with 3 different oral glycoprotein IIb/IIIa inhibitor agents, this was associated with a reduction in the need for urgent revascularization and no increase in myocardial infarction. These findings suggest the potential for a direct toxic effect with these agents and argue against a prothrombotic mechanism. Further investigation to elucidate the cause of this increased fatality risk is warranted.

Topics: Administration, Oral; Alanine; Aspirin; Benzamidines; Clinical Trials, Phase III as Topic; Coronary Disease; Dose-Response Relationship, Drug; Drug Therapy, Combination; Hemorrhage; Humans; Incidence; Multicenter Studies as Topic; Myocardial Infarction; Oximes; Piperidines; Platelet Glycoprotein GPIIb-IIIa Complex; Pyrrolidines; Randomized Controlled Trials as Topic

The contributions of remifentanil to anesthesia for heart surgery is described. The pharmacokinetic properties are described along with our clinical experience with the various modes and doses of perfusion for induction as well as during and after surgery.

Topics: Analgesics; Anesthesia, Conduction; Anesthesia, General; Anesthesia, Inhalation; Anesthesia, Intravenous; Anesthetics, Inhalation; Anesthetics, Intravenous; Cardiac Surgical Procedures; Extracorporeal Circulation; Half-Life; Hemodynamics; Humans; Methyl Ethers; Myocardial Infarction; Myocardium; Neuromuscular Nondepolarizing Agents; Oxygen Consumption; Pain, Postoperative; Piperidines; Postoperative Complications; Propofol; Remifentanil; Sevoflurane; Stress, Physiological; Sympathetic Nervous System

Platelet membrane glycoprotein IIb/IIIa inhibitors, a new class of potent antiplatelet agents, have been used in the treatment of acute coronary syndromes as well as in the prevention of complications after percutaneous coronary interventions. Approximately 50,000 patients with coronary artery disease have been enrolled in randomized studies of glycoprotein IIb/IIIa inhibitors. The purpose of this article is to review the pharmacology of glycoprotein IIb/IIIa inhibitors, the results of the clinical trials using these agents, and their current use in percutaneous coronary interventions and the treatment of acute coronary syndromes.

Topics: Abciximab; Acetates; Acute Disease; Administration, Oral; Alanine; Angioplasty, Balloon, Coronary; Antibodies, Monoclonal; Anticoagulants; Benzamidines; Coronary Disease; Eptifibatide; Hemorrhage; Humans; Immunoglobulin Fab Fragments; Myocardial Infarction; Oximes; Peptides; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pyrrolidines; Randomized Controlled Trials as Topic; Stents; Syndrome; Thrombocytopenia; Thrombolytic Therapy; Tirofiban; Tyrosine

Platelet aggregation plays a central role in the pathogenesis of thrombosis and the acute coronary syndromes. When given intravenously, potent selective antagonists of fibrinogen binding to the glycoprotein (GP) IIb/IIIa receptor, the final common pathway for platelet aggregation, have been effective in the treatment of acute coronary syndromes. Their benefit ceases, however, with the end of the infusion. Aspirin reduces the incidence of secondary vascular events by 25% to 30% after an acute coronary syndrome, and clopidogrel provides modest improvement over aspirin. However, both are relatively weak antiplatelet agents that each block only one of many pathways to platelet activation and surface membrane expression of the competent GP IIb/IIIa receptor. With the success of the intravenous GP IIb/IIIa antagonists in the acute setting, recent interest has focused on the potential benefit of oral GP IIb/IIIa antagonists used long-term for secondary prevention. The oral agents tested in phase III studies thus far have not performed up to expectations, however. The following paper reviews these studies and the implications of their results.

Topics: Alanine; Angina, Unstable; Aspirin; Benzamidines; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Humans; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pyrrolidines; Syndrome; Treatment Outcome

The central role of platelet-rich thrombus in the pathogenesis of acute coronary syndromes (ACSs) is well-known. Glycoprotein IIb/IIIa (Gp IIb/IIIa) receptor antagonists are potent inhibitors of platelet function that may be expected to affect favorably the natural history of ACSs.. To define the optimal role of Gp IIb/IIIa inhibitors in treatment strategies for ACSs.. A MEDLINE search was performed to identify all English-language articles regarding use of Gp IIb/IIIa inhibitors in ACSs published between 1966 and June 2000. In addition, relevant abstracts from the annual meetings of the American Heart Association, American College of Cardiology, and the European Society of Cardiology were reviewed.. Only studies of 500 or more patients were included. Of 15 studies identified, 10 randomized, placebo-controlled, double-blind trials of Gp IIb/IIIa inhibitors in ACSs were selected for review.. Data quality was determined by publication in the peer-reviewed literature or presentation at an official cardiology society-sponsored meeting, as well as by verification with the primary author.. Three members of this class of drugs are available for intravenous use. Abciximab, eptifibatide, and tirofiban hydrochloride, each have data demonstrating their value in improving the outcomes of patients presenting with ACSs. Current evidence supports use of these drugs in both conservative and invasive treatment strategies. Glycoprotein IIb/IIIa-blocking therapy is safe, and with proper precautions, bleeding risks can be minimized. Biological differences exist among these agents, but as of yet, no head-to-head comparisons have been made of their clinical efficacy. Unlike intravenous Gp IIb/IIIa inhibitors, available data regarding any role of oral Gp IIb/IIIa inhibitors are not favorable.. Current data indicate that intravenous Gp IIb/IIIa inhibitor therapy merits a prominent role in the initial management of patients with ACSs. JAMA. 2000;284:1549-1558.

Topics: Abciximab; Acute Disease; Alanine; Angina, Unstable; Angioplasty, Balloon, Coronary; Antibodies, Monoclonal; Anticoagulants; Benzamidines; Drug Therapy, Combination; Eptifibatide; Heparin, Low-Molecular-Weight; Humans; Immunoglobulin Fab Fragments; Myocardial Infarction; Oximes; Peptides; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pyrrolidines; Randomized Controlled Trials as Topic; Stents; Tirofiban; Tyrosine

Topics: Anilides; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzeneacetamides; Coronary Disease; Encainide; Flecainide; Heart Ventricles; Humans; Lidocaine; Mexiletine; Myocardial Infarction; Piperidines; Tachycardia; Tocainide; Ventricular Fibrillation

Topics: Administration, Oral; Anti-Arrhythmia Agents; Coronary Disease; Death, Sudden; Dose-Response Relationship, Drug; Humans; Infusions, Parenteral; Kinetics; Lidocaine; Myocardial Infarction; Piperidines; Propranolol

Acute myocardial infarction (AMI) is a leading cause of death and disability worldwide. Previous investigations have demonstrated that curcumin has a cardioprotective effect and may improve myocardial injury. So this study was performed to assess whether supplementation with curcumin could diminish myocardial injury following AMI.. To conduct this randomized, double-blinded, and placebo-controlled clinical trial, seventy-two patients with acute myocardial infarction, aged 18-75 years, were enrolled and randomly divided into the active intervention and control groups. The active intervention group (n = 38) received curcumin capsules with piperine supplement (500 mg/day, 95% curcuminoids) for 8 weeks, whereas the control group (n = 34) received a placebo capsule. At the baseline and end of the study, ejection fraction was assessed, and blood samples were taken from all patients to measure the levels of cardiac troponin I(cTnI), lipid profile, FBG, HbA1C, liver enzymes, renal function parameters, and electrolytes.. In this trial, curcumin supplementation significantly reduced the levels of HbA1C (-0.3 ± 2.2 vs. +1.1 ± 1.3, P = 0.002), LDL (-10.3 ± 20.7 vs. +0.2 ± 22.5, P = 0.039), ALT (-10.2 ± 28.5 vs. +7.3 ± 39.2, P = 0.029), and ALP (+6.4 ± 39.5 vs. +38.0 ± 69.0, P = 0.018) compared to the placebo group. Moreover, the serum concentration of HDL significantly improved in comparison with the placebo group (+4.5 ± 8.9 vs. -1.6 ± 7.7, P = 0.002). However, no substantial difference was perceived between the groups regarding the ejection fraction and serum levels of cTnI, FBG, renal function parameters, and electrolytes.. Our results indicated that daily intake of 500 mg of curcumin capsules with piperine supplement for 8 weeks modified lipid profile, liver enzymes, and glycemic status, but did not have any effect on ejection fraction and serum concentration of cardiac troponin I, renal function parameters, and electrolytes in acute myocardial infarction patients.

Topics: Alkaloids; Benzodioxoles; Curcumin; Dietary Supplements; Double-Blind Method; Humans; Myocardial Infarction; Piperidines; Polyunsaturated Alkamides

Patients with diabetes who had a recent myocardial infarction (MI) are at high risk of cardiovascular events. Therefore, risk assessment is important for treatment and shared decisions. We used data from EXAMINE trial to investigate whether a multi-proteomic approach would provide specific proteomic signatures and also improve the prognostic capacity for determining the risk of cardiovascular death, MI, stroke, heart failure [HF], all-cause death, and combinations of these outcomes.. 93 circulating proteins (92 from the Olink® CVDII plus troponin) were assessed in 5131 patients. Cox, competing risks, and reclassification measures were applied.. The clinical model showed good discrimination and calibration for all outcomes. On top of the clinical model that included age, sex, smoking, diabetes duration, history of MI (prior to the index MI of inclusion), history of HF hospitalization, history of stroke, atrial fibrillation, hypertension, systolic blood pressure, statin therapy, estimated glomerular filtration rate, and study treatment (alogliptin or placebo), troponin and BNP added prognostic information to the composite of cardiovascular death, MI, or stroke (∆C-index + 5%) and cardiovascular death alone (∆C-index + 7%). Troponin, BNP, and TRAILR2 added prognostic information on all-cause death and the composite of cardiovascular death or HF hospitalization. HF hospitalization alone was improved by adding BNP and Gal-9. For MI, troponin, FGF23, and AMBP added prognostic value; whereas for stroke, only troponin added prognostic value (multi-proteomics improved C-index > 3% [p < 0.001] for all the studied outcomes). The addition of the final biomarker selection to the clinical model improved event reclassification (cNRI from + 23% to + 64%). Specifically, the addition of the biomarkers allowed a better classification of patients at low risk (as having "true" low risk) and patients and high risk (as having "true" high risk). These results were consistent for all the studied outcomes with even more marked differences in the fatal events.. The addition of multi-proteomic biomarkers to a clinical model in this population with diabetes and a recent MI allowed a better risk prediction and event reclassification, potentially helping for better risk assessment and targeted treatment decisions. T2D type 2 diabetes, MI myocardial infarction, CV cardiovascular, HFH heart failure hospitalization, Δ delta, cNRI continuous net reclassification index, BNP brain natriuretic peptide, TRAILR2 trail receptor 2 (or death receptor 5), Gal-9 galectin-9, FGF23 fibroblast growth factor 23.

Topics: Biomarkers; Cause of Death; Comorbidity; Diabetes Mellitus, Type 2; Female; Fibroblast Growth Factor-23; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Natriuretic Peptide, Brain; Piperidines; Prognosis; Proteomics; Risk Assessment; Survival Rate; Uracil

The timing of enrolment following an acute coronary syndrome (ACS) may influence cardiovascular (CV) outcomes and potentially treatment effect in clinical trials. Understanding the timing and type of clinical events after an ACS will allow for clinicians to better tailor evidence-based treatments to optimize therapeutic effect. Using a large contemporary trial in patients with type 2 diabetes mellitus (T2DM) post-ACS, we examined the impact of timing of enrolment on subsequent CV outcomes.. EXAMINE was a randomized trial of alogliptin versus placebo in 5,380 patients with T2DM and a recent ACS from October 2009 to March 2013. The primary outcome was a composite of CV death, nonfatal myocardial infarction (MI), or nonfatal stroke. The median follow-up was 18 months. In this post hoc analysis, we examined the occurrence of subsequent CV events by timing of enrollment divided by tertiles of time from ACS to randomization: 8-34, 35-56, and 57-141 days.. Patients randomized early (compared to the latest times) had less comorbidities at baseline including a history of heart failure (HF; 24.7% vs 33.0%), prior coronary artery bypass graft (9.6% vs 15.9%), or atrial fibrillation (5.9% vs 9.4%). Despite the reduced comorbidity burden, the risk of the primary outcome was highest in patients randomized early compared to the latest time (adjusted hazard ratio 1.47; 95% CI 1.21-1.74). Similarly, patients randomized early had an increased risk of recurrent MI (adjusted hazard ratio 1.51; 95% CI 1.17-1.96) and HF hospitalization (1.49; 95% CI 1.05-2.10).. In a contemporary cohort of T2DM with a recent ACS, the risk for recurrent CV events including MI and HF hospitalization is elevated early after an ACS. Given the emergence of antihyperglycemic therapies that reduce the risk of MI and HF among patients with T2DM at high CV risk, future studies evaluating the initiation of these therapies in the early period following an ACS are warranted given the large burden of potentially modifiable CV events.

Topics: Acute Coronary Syndrome; Comorbidity; Diabetes Mellitus, Type 2; Evidence-Based Practice; Female; Heart Disease Risk Factors; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Outcome and Process Assessment, Health Care; Patient Selection; Piperidines; Random Allocation; Risk Assessment; Stroke; Time Factors; Uracil

We sought to assess the risk of major adverse cardiovascular events (MACE) by utilizing high-sensitivity C-reactive protein (hsCRP) level and low-density lipoprotein cholesterol (LDL-C) in patients with type 2 diabetes and recent acute coronary syndrome.. Study participants enrolled in the EXAMINE trial (Clinical trials registration number: NCT00968708) and were stratified by baseline hsCRP levels (<1, 1-3 and >3 mg/L). They were also sub-divided into 4 groups according to baseline hsCRP (≤3 or >3 mg/L) and achieved LDL-C (<70 or ≥70 mg/dL) levels. Among 5380 patients, the MACE rate, a composite of cardiovascular death, non-fatal acute myocardial infarction and non-fatal stroke, was evaluated during the 30 months of follow-up.. Cumulative incidence of MACE was 11.5% (119 events), 14.6% (209 events) and 18.4% (287 events) in patients with hsCRP levels of <1, 1 to 3 and >3 mg/L, respectively (P < .001). In patients with hsCRP >3 mg/L, the adjusted hazard ratio (95% confidence interval) was 1.42 (1.13, 1.78; P = .002) for MACE compared with patients with hsCRP <1 mg/L. MACE cumulative incidences were 11.0% (128 events), 14.4% (100 events), 15.6% (194 events) and 21.3% (182 events) in patients with low LDL-C and low hsCRP, low LDL-C and high hsCRP, high LDL-C and low hsCRP, and high LDL-C and high hsCRP levels, respectively (P < .001).. Levels of hsCRP were associated with recurrent cardiovascular events in patients with type 2 diabetes and recent acute coronary syndrome, and this association appears to be independent of and additive to the achieved LDL-C level.

Topics: Acute Coronary Syndrome; C-Reactive Protein; Cholesterol, LDL; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Double-Blind Method; Female; Heart Failure; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Piperidines; Standard of Care; Treatment Outcome; Uracil

Alogliptin, a dipeptidyl peptidase-4 inhibitor, is approved for the treatment of patients with type 2 diabetes (T2DM). EXAMINE was a randomized controlled clinical trial designed to demonstrate the cardiovascular (CV) safety of alogliptin. In the trial, 5380 patients with established T2DM who had a recent acute coronary syndrome event (between 15 and 90 days) were randomized to treatment with either alogliptin or placebo. To better understand and describe the CV safety of alogliptin, we analyzed data from the EXAMINE trial to determine whether treatment with alogliptin affected recurrent and total CV events. Poisson regression analysis compared the total number of occurrences of CV death, MI, stroke, unstable angina, and coronary revascularization between all patients randomized to alogliptin vs placebo groups. Patients with recurrent CV events were older and more likely to have renal disease and history of heart failure. There were 1100 first CV events and an additional 666 recurrent events over a median of 18 months of follow-up. There were no significant differences with regard to total number of events in patients treated with alogliptin (n = 873) or placebo (n = 893; P = 0.52). Furthermore, there were no differences in the types of events seen in patients treated with alogliptin or placebo. Alogliptin did not increase the risk of either first or recurrent CV events when compared with placebo in patients with T2DM and recent acute coronary syndrome. These data support the CV safety of alogliptin in patients who are at increased risk of future CV events.

Topics: Acute Coronary Syndrome; Aged; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Piperidines; Stroke; Survival Rate; Treatment Outcome; United States; Uracil

Antihyperglycemic therapies may increase the risk of cardiovascular events including hospitalization for heart failure. There is a paucity of data evaluating the cardiovascular safety of antihyperglycemic therapies in the high-risk period following an acute coronary syndrome (ACS).. The EXAMINE (Examination of Cardiovascular Outcomes with Alogliptin versus Standard of Care) trial randomized 5380 patients who were 15 to 90 days post ACS to the dipeptidyl dipeptidase-IV (DPP-IV) inhibitor alogliptin versus placebo; mean follow-up was 18 months. Using a landmark analysis, we assessed the (1) burden of cardiovascular events from randomization to 6 months (early period) and from 6 months to the end of follow-up (late period) and (2) the risk of cardiovascular events associated with early (up to 6 months) and chronic (6 months to end of follow-up) DPP-IV inhibition with alogliptin. Patients with early versus late events had similar baseline demographic profiles. Overall, 42.1% of the composite of cardiovascular death/myocardial infarction/stroke and 47.5% of hospitalization for heart failure occurred in the early period. Early DPP-IV inhibition did not increase the risk of early cardiovascular death/myocardial infarction/stroke (hazard ratio 0.96, 95% confidence interval, 0.76-1.21) or hospitalization for heart failure (1.23, 95% confidence interval, 0.84-1.82). Similarly, chronic DPP-IV inhibition did not increase the risk of late cardiovascular death/myocardial infarction/stroke (hazard ratio 1.03, 95% confidence interval, 0.89-1.26) or hospitalization for heart failure (hazard ratio 1.02, 95% confidence interval, 0.85-1.22).. Early after an ACS, patients with type 2 diabetes mellitus experience a significant burden of HF events and recurrent ACS. DPP-IV inhibition with alogliptin appears to be safe even in the high-risk period following an ACS.

Topics: Acute Coronary Syndrome; Aged; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Double-Blind Method; Female; Heart Failure; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Recurrence; Risk Assessment; Risk Factors; Stroke; Time Factors; Treatment Outcome; Uracil

Concerns raised regarding adverse cardiovascular (CV) outcomes with new therapies for type 2 diabetes mellitus (T2DM) have led to several large-scale CV outcome trials. The EXAMINE trial confirmed noninferiority of the dipeptidyl dipeptidase 4 inhibitor alogliptin to placebo on major adverse cardiac event rates in a post-acute coronary syndrome (ACS) T2DM population. We present data on additional ischemic cardiac events and CV hospitalizations in EXAMINE.. Patients with T2DM and an ACS event in the previous 15 to 90 days were randomly assigned to alogliptin or placebo on a background of standard treatment for diabetes. The incident rates of a 5-component composite end point of CV death, stroke, myocardial infarction, unstable angina, and coronary revascularization as well as CV hospitalization were calculated in all participants and according to macrovascular disease at baseline.. There were no significant differences between alogliptin (n = 2,701) and placebo (n = 2,679) in the event rate of the 5-component composite endpoint with median follow-up 533 days (21.0% vs 21.5%, hazard ratio [HR] 0.98 [0.87-1.10], P = .72). No differences were observed in terms of CV hospitalization (25.0% vs 25.4%, HR 0.98 [0.88-1.09], P = .70) or coronary revascularization (10.6% vs 10.2%, HR 1.05 [0.88-1.09], P = .60). No interactions were observed for treatment and prior macrovascular disease.. EXAMINE demonstrates that there was no increase in the risk of cardiac ischemic events and CV hospitalizations with alogliptin in a high-risk post-ACS patient population. Because these are major driver of overall health care costs, these data suggest that there would be no adverse impact on health care resource utilization.

Topics: Acute Coronary Syndrome; Aged; Diabetes Mellitus, Type 2; Female; Hospitalization; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Outcome and Process Assessment, Health Care; Piperidines; Risk Assessment; Standard of Care; Stroke; Uracil

The EXAMINE trial showed non-inferiority of the DPP-4 inhibitor alogliptin to placebo on major adverse cardiac event (MACE) rates in patients with type 2 diabetes and recent acute coronary syndromes. Concerns about excessive rates of in-hospital heart failure in another DPP-4 inhibitor trial have been reported. We therefore assessed hospital admission for heart failure in the EXAMINE trial.. Patients with type 2 diabetes and an acute coronary syndrome event in the previous 15-90 days were randomly assigned alogliptin or placebo plus standard treatment for diabetes and cardiovascular disease prevention. The prespecified exploratory extended MACE endpoint was all-cause mortality, non-fatal myocardial infarction, non-fatal stroke, urgent revascularisation due to unstable angina, and hospital admission for heart failure. The post-hoc analyses were of cardiovascular death and hospital admission for heart failure, assessed by history of heart failure and brain natriuretic peptide (BNP) concentration at baseline. We also assessed changes in N-terminal pro-BNP (NT-pro-BNP) from baseline to 6 months. This study is registered with ClinicalTrials.gov, number NCT00968708.. 5380 patients were assigned to alogliptin (n=2701) or placebo (n=2679) and followed up for a median of 533 days (IQR 280-751). The exploratory extended MACE endpoint was seen in 433 (16·0%) patients assigned to alogliptin and in 441 (16·5%) assigned to placebo (hazard ratio [HR] 0·98, 95% CI 0·86-1·12). Hospital admission for heart failure was the first event in 85 (3·1%) patients taking alogliptin compared with 79 (2·9%) taking placebo (HR 1·07, 95% CI 0·79-1·46). Alogliptin had no effect on composite events of cardiovascular death and hospital admission for heart failure in the post hoc analysis (HR 1·00, 95% CI 0·82-1·21) and results did not differ by baseline BNP concentration. NT-pro-BNP concentrations decreased significantly and similarly in the two groups.. In patients with type 2 diabetes and recent acute coronary syndromes, alogliptin did not increase the risk of heart failure outcomes.. Takeda Development Center Americas.

Topics: Acute Coronary Syndrome; Aged; Angina, Unstable; Diabetes Mellitus, Type 2; Diabetic Cardiomyopathies; Double-Blind Method; Female; Heart Failure; Hospitalization; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Natriuretic Peptide, Brain; Peptide Fragments; Piperidines; Risk Factors; Stroke; Uracil

Topics: Administration, Oral; Angina, Unstable; Biomarkers; Diabetes Mellitus, Type 2; Double-Blind Method; Follow-Up Studies; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Myocardial Infarction; Piperidines; Practice Guidelines as Topic; Research Design; Risk Factors; Treatment Outcome; Uracil

To assess potentially elevated cardiovascular risk related to new antihyperglycemic drugs in patients with type 2 diabetes, regulatory agencies require a comprehensive evaluation of the cardiovascular safety profile of new antidiabetic therapies. We assessed cardiovascular outcomes with alogliptin, a new inhibitor of dipeptidyl peptidase 4 (DPP-4), as compared with placebo in patients with type 2 diabetes who had had a recent acute coronary syndrome.. We randomly assigned patients with type 2 diabetes and either an acute myocardial infarction or unstable angina requiring hospitalization within the previous 15 to 90 days to receive alogliptin or placebo in addition to existing antihyperglycemic and cardiovascular drug therapy. The study design was a double-blind, noninferiority trial with a prespecified noninferiority margin of 1.3 for the hazard ratio for the primary end point of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke.. A total of 5380 patients underwent randomization and were followed for up to 40 months (median, 18 months). A primary end-point event occurred in 305 patients assigned to alogliptin (11.3%) and in 316 patients assigned to placebo (11.8%) (hazard ratio, 0.96; upper boundary of the one-sided repeated confidence interval, 1.16; P<0.001 for noninferiority). Glycated hemoglobin levels were significantly lower with alogliptin than with placebo (mean difference, -0.36 percentage points; P<0.001). Incidences of hypoglycemia, cancer, pancreatitis, and initiation of dialysis were similar with alogliptin and placebo.. Among patients with type 2 diabetes who had had a recent acute coronary syndrome, the rates of major adverse cardiovascular events were not increased with the DPP-4 inhibitor alogliptin as compared with placebo. (Funded by Takeda Development Center Americas; EXAMINE ClinicalTrials.gov number, NCT00968708.).

Topics: Aged; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Double-Blind Method; Female; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Piperidines; Uracil

Evidence-based medications (EBM) are underused in older patients despite potentially larger absolute benefits. Little is known about factors influencing prescribing in the elderly with acute coronary syndromes.. Among the 15,904 patients from the Sibrafiban vs aspirin to Yield Maximum Protection from ischemic Heart events postacute cOroNary sYndromes (SYMPHONY) and second SYMPHONY trials, we examined the rates of use of EBM according to age (< 75 or > or = 75 years, and 3 subgroups of 5 year increments among patients > or = 75 years).. Ninety-day mortality increased with age (< 75 years, 1.3%; > or = 75 to < 80 years, 4.4%; > or = 80 to < 85 years, 6.0%; > or = 85 years, 9.6%). Compared with subjects < 75 years (n = 14,043), acute EBM use was lower among patients > or = 75 years (n = 1794): aspirin (83% vs 85%), heparin (73% vs 78%), and beta-blockers (70% vs 76%). Similarly, discharge use of beta-blockers (69% vs 76%) and statins (28% vs 40%) was lower, although this was not the case for angiotensin-converting enzyme inhibitors (44% vs 41%). These patterns persisted among eligible patients. Beyond the age of 75 years, EBM use was not further influenced by age except for statins and angiotensin-converting enzyme inhibitors, which were used less frequently in those > or = 85 years. Among patients aged > or = 75 years, prediction for use of each EBM in multivariable modeling was modest (C indices, approximately 0.7); except for statins, increasing age did not predict lower EBM use.. Despite higher mortality risk, EBM use was lower among older patients even considering eligibility. Among those aged > or = 75 years, age was no longer the major factor predicting EBM use. The modest C indices suggest other factors are associated with prescribing, underscoring the need for treatment algorithms and quality assurance measures in older patients.

Topics: Aged; Aged, 80 and over; Angina, Unstable; Aspirin; Cardiovascular Agents; Evidence-Based Medicine; Female; Humans; Male; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors

Stroke is a rare but serious event that complicates the course of patients with acute coronary syndromes (ACS). The type, outcome, and risk factors of stroke occurring in stabilized patients with ACS have not been previously reported.. We evaluated stroke incidence, subtypes, and outcomes, in addition to demographics and clinical risk characteristics associated with stroke among patients enrolled in the Sibrafiban versus Aspirin to Yield Maximum Protection from Ischemic Heart Events Post-acute Coronary Syndromes (SYMPHONY) and 2nd SYMPHONY trials.. Of 15,904 stabilized patients with ACS, 113 (0.71%) had a stroke over a median follow-up of 90 days. The majority of strokes occurred within 30 days of presentation, and the time course for stroke occurrence paralleled that of myocardial (re)infarction. Most strokes were ischemic (78%), and 52% resulted in moderate or severe disability or death. Patients with stroke were older and more often had hypertension, diabetes, peripheral vascular disease, and atrial fibrillation. Among patients with stroke who had cardiac catheterization, percutaneous coronary intervention, or coronary artery bypass grafting, stroke occurred predominantly after the procedure. No difference in occurrence or type of stroke was observed in the assigned treatment groups. In multivariable modeling age, heart failure, prior stroke, left bundle branch block, and systolic blood pressure predicted the occurrence of stroke.. In patients stabilized after presenting with a spectrum of ACS and treated with sibrafiban and/or aspirin, stroke occurred in fewer than 1% within 90 days but carried a significant mortality and morbidity risk.

Topics: Acute Disease; Aged; Angina, Unstable; Angioplasty, Balloon, Coronary; Aspirin; Coronary Artery Bypass; Female; Follow-Up Studies; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Proportional Hazards Models; Recurrence; Risk Factors; Stroke

Unstable coronary artery disease (CAD) is a multifactorial disease involving both thrombotic and inflammatory processes. We have assessed the time-course and the influence of thrombin inhibitors on changes in fibrinogen and C-reactive protein levels, and their relation to myocardial ischaemia in unstable CAD.. Three hundred and twenty patients were randomized to 72 h infusion with three different doses of inogatran, a direct thrombin inhibitor, or unfractionated heparin. There were no significant differences between the treatment groups in fibrinogen or C-reactive protein levels. Overall, the fibrinogen levels were significantly increased in the first 24-96 h and still elevated at 30 days. The C-reactive protein levels showed a more pronounced increase during the first 24-96 h, but then markedly decreased over 30 days. Troponin-positive compared to troponin-negative patients had higher fibrinogen and C-reactive protein levels up to 96 h, although there was an increase compared to pre-treatment levels in both groups. A high fibrinogen level (pre-treatment top tertile) was associated with an increased rate of death or myocardial (re-)infarction at 30 days, 13% vs 5.6%, P=0.03, and increased long-term mortality. A high C-reactive protein level was related to increased 30-day mortality, 4% vs 0%, P=0.01.. Myocardial cell injury was related to a high degree of inflammation, only some of which is an acutephase response due to tissue damage. The rise in fibrinogen was sustained, which might reflect low grade inflammation with long-term risk of thrombosis. The transient elevation of C-reactive protein levels might indicate a propensity to a pronounced inflammatory response and is associated with increased mortality.

Topics: Adult; Aged; Aged, 80 and over; Antithrombins; C-Reactive Protein; Coronary Disease; Female; Fibrinogen; Follow-Up Studies; Glycine; Humans; Male; Middle Aged; Myocardial Infarction; Myocarditis; Piperidines; Survival Analysis; Troponin T

We sought to assess the incidence and clinical significance of elevated cardiac troponin I (cTnI) after percutaneous coronary intervention (PCI).. Elevated creatine kinase-MB (CK-MB) is prognostically important after PCI, but the prognostic significance of elevated cTnI after PCI is uncertain.. In a prospective substudy of the Sibrafiban Versus Aspirin to Yield Maximum Protection From Ischemic Heart Events Post-acute Coronary Syndromes (SYMPHONY) trials, which randomized patients with acute coronary syndromes (ACS) to receive aspirin or sibrafiban, we measured cTnI (positive, > or =1.5 ng/ml) and CK-MB (positive, > or =7 ng/ml) in 481 patients with PCI. Samples were collected immediately before and at 0, 8 and 16 h after PCI and analyzed by a core laboratory. The primary end point was the Kaplan-Meier estimate of death, myocardial infarction or severe, recurrent ischemia at 90 days.. Overall, 230 patients (48%) had elevated cTnI after PCI. Such patients underwent PCI sooner and were more likely to have coronary stenting. Elevated cTnI was associated with nonsignificantly higher risks of the primary end point (11.5% vs. 8.7%; p = 0.15) and of death (1.8% vs. 0.4%; p = 0.4) and a significantly higher risk of death or infarction (10.6% vs. 4.2%; p = 0.005). This pattern was more pronounced for patients who became positive only after PCI: primary end point, 20.7% vs. 10.1% for patients who remained negative after PCI (p = 0.05); death, 5.2% vs. 0% (p = 0.02); death or infarction, 18.1% vs. 4.1% (p = 0.007).. Elevated cTnI, often observed after PCI in patients with ACS, is associated with worse 90-day clinical outcomes. This marker, therefore, is a useful prognostic indicator in such patients.

Topics: Angina, Unstable; Angioplasty, Balloon, Coronary; Aspirin; Biomarkers; Creatine Kinase; Creatine Kinase, MB Form; Disease-Free Survival; Female; Heart Diseases; Humans; Isoenzymes; Male; Middle Aged; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Prognosis; Prospective Studies; Sensitivity and Specificity; Stents; Troponin I

The performance of the cardiovascular system depends on the interaction of the left ventricle and arterial system. An appropriate coupling of these two components is important to quantify the efficiency of myocardium, determined by Ea/Ees. The end-systolic elastance of the left ventricle (Ees) is an index of contractility which is independent of loading conditions, while the arterial end-systolic elastance (Ea) represents the properties of the arterial system. The aim of our study is to investigate the effects of a bolus of remifentanil (R) on myocardial efficiency.. In a period of 3 months we examined prospectively the effects of R in a group of 12 patients, ASA IV, 49-75 years old, submitted intraoperatively to cardiac anesthesia for revascularization of myocardium. After induction of anesthesia and before the beginning of surgery, a bolus of R (1 mg/kg/min) was administered and with the use of trans-esophageal echocardiography we determined both the left ventricle end-systolic volume and end-diastolic volume to assess, with different end-systolic arterial pressures, the ventricle elastance (Ees) and arterial elastance (Ea) before and after administration of R.. The present findings indicate that R decreases the ventricular elastance from 6.07 mmHg/ml/m2 to 4.8, with a less decrease of arterial elastance from 3.69 mmHg/ml/m2 to 3.07.. The results suggest that R preserves a good left ventricular-arterial coupling and mechanical efficiency, despite a little increase of coupling, probably because ventricular and arterial properties are so matched as to minimize the systolic work of the left ventricle.

Topics: Aged; Anesthetics, Intravenous; Aorta; Cardiovascular Agents; Combined Modality Therapy; Coronary Artery Bypass; Coronary Disease; Echocardiography, Transesophageal; Electric Impedance; Female; Heart Failure; Heart Rate; Hemorheology; Humans; Injections, Intravenous; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Oxygen Consumption; Piperidines; Propofol; Prospective Studies; Remifentanil; Stroke Volume; Thiopental; Vascular Resistance; Vecuronium Bromide; Ventricular Function, Left

In the current study, we investigated molecular markers of coagulation activity, ie, prothrombin fragment 1+2 (F1+2), thrombin-antithrombin (TAT) complex, soluble fibrin (SF), and D-dimer, and their relation to death, myocardial infarction, and refractory angina during and after anticoagulant treatment in unstable coronary artery disease. Patients with unstable coronary artery disease (N=320) were randomized to a 72-hour infusion with either inogatran, a low-molecular-mass direct thrombin inhibitor, or unfractionated heparin. During the 30-day follow-up, a 40% lower event rate was seen in patients with high compared with low baseline levels of TAT or SF. High baseline levels of coagulation activity were correlated with a larger decrease during treatment. Patients with decreased compared with raised F1+2 or TAT levels after 6 hours of treatment had a 50% lower event rate at 30 days (F1+2, P=0.04; TAT, P=0.02). At the cessation of antithrombin treatment, there was a clustering of cardiac events that tended to be related to a rise in the levels of TAT and the other markers. During long-term follow-up (median, 29 months), there was a relation between higher baseline levels of D-dimer (P=0.003) and increased mortality. High baseline levels of molecular markers of coagulation activity might identify patients with a thrombotic condition (as the major cause of instability) who are good responders to anticoagulant therapy, with a larger decrease in coagulation activity during treatment and a decreased risk of ischemic events. However, this early benefit is lost during long-term follow-up when high baseline levels of coagulation activity are associated with a raised risk of early reactivation and increased mortality.

Topics: Adult; Aged; Angina, Unstable; Anticoagulants; Antithrombin III; Antithrombins; Biomarkers; Blood Coagulation; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Follow-Up Studies; Glycine; Heparin; Humans; Kinetics; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Peptide Hydrolases; Piperidines; Prothrombin; Random Allocation; Treatment Outcome

Platelets play a key role in the pathogenesis of atherosclerosis, thrombosis, and acute coronary and cerebrovascular syndromes. Inhibition of platelet function by acetylsalicylic acid (aspirin) has been shown to reduce the incidence atherothrombotic events in patients with coronary, cerebrovascular, or peripheral vascular disease. Thienopyridine agents, however, including ticlopidine and clopidogrel, inhibit the adenosine diphosphate receptor and have modestly superior effects compared with aspirin on reduction of death, myocardial infarction, and stroke among a broad group of patients with vascular disease. More effective antithrombotic agents are still required to treat patients at high risk for recurrent vascular events.. Lotrafiban, a selective, nonpeptide antagonist of the human platelet fibrinogen receptor (glycoprotein [GP] IIb/IIIa [alphaIIb/beta3 integrin]), blocks the binding of fibrinogen to the GP IIb/IIIa receptor, which is the final common pathway of platelet aggregation. Lotrafiban at doses of up to 50 mg twice daily was well-tolerated in a 12-week, double-blind, placebo-controlled, dose-ranging study in patients with recent myocardial infarction, unstable angina, transient ischemic attack, or stroke when added to aspirin therapy. On the basis of these results, a dosing regimen was selected for the phase III Blockage of the Glycoprotein IIb/IIIa Receptor to Avoid Vascular Occlusion (BRAVO) trial based on pharmacodynamics and drug tolerability. In the pivotal BRAVO study, lotrafiban therapy is being evaluated in patients who have had a recent myocardial infarction, unstable angina, transient ischemic attack, or ischemic stroke, or who present at any time after a diagnosis of peripheral vascular disease combined with either cardiovascular or cerebrovascular disease.. The efficacy evaluation will be based on a composite end point of clinical events (death by any cause, myocardial infarction, stroke, recurrent ischemia requiring hospitalization, or urgent ischemia-driven revascularization). The target enrollment is 9200 patients worldwide. Approximately 700 centers will participate and will be distributed within 30 countries across North America, Europe, Australia, and Asia.

Topics: Administration, Oral; Adolescent; Arterial Occlusive Diseases; Benzodiazepines; Double-Blind Method; Drug Evaluation; Female; Humans; Ischemic Attack, Transient; Male; Myocardial Infarction; Myocardial Ischemia; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Research Design; Secondary Prevention; Stroke

Patients with unstable coronary syndromes are a heterogeneous group with varying degrees of ischemia and prognosis. The present study compares the prognostic value of a standard electrocardiogram (ECG) obtained at admission to the hospital with the information from 24-hour continuous electrocardiographic monitoring obtained immediately after admission. The admission ECGs and 24 hours of vectorcardiographic (VCG) monitoring from 308 patients admitted with unstable coronary artery disease were analyzed centrally regarding standard electrocardiographic ST-T changes, ST-vector magnitude (ST-VM), and ST change vector magnitude episodes. End points were death, acute myocardial infarction, and refractory angina pectoris within a 30-day follow-up period. ST-VM episodes (> or = 50 microV for > or = 1 minute) during VCG monitoring was the only independent predictor of death or acute myocardial infarction by multivariate analysis. ST-VM episodes during vectorcardiography was associated with a relative risk of 12.7 for having a cardiac event, hypertension was associated with a relative risk of 1.7, and ST depression on the admission ECG was associated with a relative risk of 5.7. Patients with ST depression at admission had an event rate (death or acute myocardial infarction) of 17% at 30-day follow-up. Patients without ST depression could further be risk stratified by 24 hours of VCG monitoring into a subgroup with ST-VM episodes at similar (8%) risk and a subgroup without ST-VM episodes at low (1%) risk (p = 0.00005). Continuous VCG monitoring provides important information for evaluating patients with unstable coronary artery disease. It is recommended that patients not initially estimated at high risk based on the admission ECG are referred for 24 hours of VCG monitoring for further risk stratification.

Topics: Aged; Angina Pectoris; Angina, Unstable; Anticoagulants; Antithrombins; Coronary Disease; Electrocardiography; Electrocardiography, Ambulatory; Female; Follow-Up Studies; Glycine; Heparin; Humans; Hypertension; Male; Multivariate Analysis; Myocardial Infarction; Myocardial Ischemia; Patient Admission; Piperidines; Prognosis; Recurrence; Risk Assessment; Risk Factors; Survival Rate; Vectorcardiography

This study was designed to determine the magnitude and time course of platelet activation during therapy of acute coronary syndromes with an oral platelet antagonist.. Platelet activation and aggregation are central to the pathogenesis of the acute coronary syndromes (ACS). However, few data are available on levels of platelet activation over time in patients with ACS, especially in the setting of chronic glycoprotein (GP) IIb/IIIa inhibition.. The Thrombolysis in Myocardial Infarction (TIMI) 12 trial was a phase II, double-blind trial evaluating the effects of sibrafiban, an oral, selective antagonist of the platelet glycoprotein IIb/IIIa receptor in patients stabilized after an ACS. A subset of 90 of the 329 patients in the study had measurement of platelet activation as assessed by the expression of platelet associated P-Selectin on days 0, 7 and 28. Platelet activation was measured in blood samples that were fixed either immediately (spontaneous activation) or after 5 minute incubation with 0, 1 microM or 5 microM ADP in order to assess platelet responsiveness to very low or moderate stimulation.. At baseline there was a significant elevation of spontaneous platelet activation as compared to samples obtained from normal donors or from patients who did not have acute coronary syndromes (ACS patients 27.6+/-18.7%, Normal controls 8.5+/-4.4%, Patient controls 10.9+/-7.1%, p < 0.005 for both). In addition, there was a significant decrease in the levels of platelet activation with time during the 28 days of treatment with sibrafiban. Nevertheless, even on day 28, the TIMI-12 patients continued to show elevated platelet activation in comparison to the control groups (p < 0.05 for both).. These results suggest that platelets remain activated long after clinical stabilization post ACS. Although platelet activation decreased after one month of oral GPIIb/IIIa inhibition, levels remained higher than normal, suggesting the need for long-term antiplatelet therapy following ACS.

Topics: Administration, Oral; Adult; Aged; Angina, Unstable; Blood Platelets; Double-Blind Method; Electrocardiography; Female; Follow-Up Studies; Humans; Male; Middle Aged; Myocardial Infarction; Oximes; P-Selectin; Piperidines; Platelet Activation; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Thrombolytic Therapy; Treatment Outcome

We investigated whether the addition of 24 h of continuous vectorcardiography ST segment monitoring (cVST) for an early (within 24 h of the latest episode of angina) determination of cardiac troponin T (cTnT) could provide additional prognostic information in patients with unstable coronary artery disease (UCAD), i.e., unstable angina and non-Q wave myocardial infarction.. Determination of cTnT at admission and cVST are individually reported to be valuable techniques for the risk assessment of patients with UCAD.. Two hundred and thirty-two patients suspected of UCAD were studied. Patients were followed for 30 days, and the occurrence of cardiac death or acute myocardial infarction (AMI) were registered.. One ST segment episode or more (relative risk [RR] 7.43, p = 0.012), a cTnT level > or = 0.20 microg/liter (RR 3.85, p = 0.036) or prestudy medication with calcium antagonists (RR 3.31, p = 0.041) were found to carry independent prognostic information after multivariate analysis of potential risk variables. By combining a cTnT determination and subsequent cVST for 24 h, subgroups of patients at high (25.8%) (n = 31), intermediate (3.1%) (n = 65) and low risk (1.7%) (n = 117) of death or AMI could be identified.. Twenty-four hours of cVST provides additional prognostic information to that of an early cTnT determination in patients suspected of having UCAD. The combination of biochemical and electrocardiographic methods provides powerful and accurate risk stratification in UCAD.

Topics: Adult; Aged; Aged, 80 and over; Angina, Unstable; Antithrombins; Coronary Disease; Death, Sudden, Cardiac; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Electrocardiography, Ambulatory; Female; Glycine; Humans; Male; Middle Aged; Myocardial Infarction; Patient Admission; Piperidines; Prognosis; Prospective Studies; Risk Assessment; Troponin T; Vectorcardiography

Aims Direct thrombin inhibitors have failed to prove superiority over unfractionated heparin in several clinical trials of unstable coronary artery disease. We have investigated the relationship between activated partial thromboplastin time levels and adverse clinical events, i.e. death, myocardial (re-)infarction or refractory angina. Methods and Results One thousand two hundred and nine patients with unstable coronary artery disease were randomized to 72 h infusion with inogatran, a low molecular mass direct thrombin inhibitor, or unfractionated heparin. During 30 days follow-up there was no significant difference between inogatran and unfractionated heparin treatment as regards clinical outcome. 11.6% of the 464 inogatran treated patients with activated partial thromboplastin time above the median at 6 h (44 s) had a clinical event in 7 days, and 6.6% of the 423 patients with activated partial thromboplastin time below the median (P=0.01). After 30 days the event rate was still 41% higher in the inogatran patients with activated partial thromboplastin time above the median (P=0.06). Activated partial thromboplastin time in quartiles indicated a direct relationship between higher activated partial thromboplastin time and worse outcome. In contrast, during heparin infusion there was a trend for improved clinical outcome with activated partial thromboplastin time above the median, but this benefit was lost after cessation of treatment.. Higher activated partial thromboplastin time levels during inogatran treatment are related to increased risk of death, myocardial infarction or refractory angina. This might, at least in part, be explained by differences in anticoagulant mechanisms between direct thrombin inhibitors and heparin, and further emphasizes the poorly defined optimal activated partial thromboplastin time range during treatment with direct thrombin inhibitors in unstable coronary artery disease.

Topics: Adult; Aged; Aged, 80 and over; Angina, Unstable; Antithrombins; Cause of Death; Coronary Disease; Dose-Response Relationship, Drug; Female; Glycine; Heparin; Humans; Infusions, Intravenous; Male; Middle Aged; Myocardial Infarction; Partial Thromboplastin Time; Piperidines; Survival Rate; Thrombin; Treatment Outcome

Unstable coronary artery disease, i.e. unstable angina or non-Q wave myocardial infarction, is caused by rupture of atheromatous plaques initiating thrombus formation. Thrombin is thought to be pivotal in platelet activation and thrombus growth. The aim of the present study was to compare the effect of three different doses of a novel, low molecular weight, selective thrombin inhibitor (inogatran) with that of heparin in unstable coronary artery disease. The composite primary end-point was death, incidence of myocardial infarction, refractory angina or recurrent angina after 7 days. Secondary end-points were the same after 3 and 30 days, as were death and myocardial infarction with or without refractory angina on all three occasions.. Patients (n = 1209) admitted with suspected unstable angina, or non-Q wave myocardial infarction, were randomly assigned to double-blind treatment with inogatran or heparin bolus doses. This was followed by a 3 day infusion with a low (LDI), medium (MDI), or high (HDI) dose of inogatran, aiming at plasma concentrations of 0.15, 0.4 or 0.8 micromol.l-1, or heparin initiated at 1200 U.h-1.. Treatment with inogatran resulted in median activated partial thromboplastin times after 24 h of 36, 44 and 53 s in the low, medium and high dose inogatran groups, respectively, as compared to 54 s in the heparin group (ns). At the end of the infusion, after 3 days, heparin-treated patients had fewer composite events (29.5%) than inogatran-treated patients (LDI = 39.4%, MDI = 37.6%, HDI = 36.1%; P = 0.01). The event rate after 7 days with respect to the primary end-point, however, did not differ between the groups (heparin = 41.0%, LDI = 45.7% MDI = 45.9%, HDI = 45.5%; ns). Death and myocardial infarction occurred less frequently in the heparin group (0.7%) than in the three inogatran groups (LDI = 3.6%, MDI = 2.0%, HDI = 4.0%; P < 0.05) after 3 days. After 7 days, this difference was attenuated (heparin = 2.6% vs LDI = 4.0%, MDI = 4.3%, HDI = 6.7%; P = 0.10). After 30 days there were no significant differences in event rates between the four groups. Major bleeding occurred in 1.1% of the patients within 7 days, with no differences between the groups.. During study drug infusion the event rate was very low in the heparin group, and none of the inogatran dosages were better than heparin in preventing ischaemic events. Furthermore, there was no relationship between event rate and inogatran dosage. Thus, this study does not indicate that the efficacy of inogatran would improve with higher doses, despite a clear dose-effect as regards the prolongation of activated partial thromboplastin time. After cessation of heparin or inogatran there was an increase in event rates, suggestive of a rebound phenomenon.

Topics: Aged; Angina, Unstable; Antithrombins; Dose-Response Relationship, Drug; Double-Blind Method; Female; Glycine; Heparin; Humans; Male; Middle Aged; Myocardial Infarction; Partial Thromboplastin Time; Piperidines; Time Factors

The acute coronary syndromes of unstable angina and non-Q-wave infarction are initiated by coronary plaque rupture and subsequent thrombus formation. Thrombin is central to this response as it activates platelets and the coagulation system. In an open design study we assessed the tolerability and safety of the low molecular weight thrombin inhibitor, inogatran, for unstable angina or non-Q-wave infarction.. Thirty-seven patients, treated within 72 h of symptoms, were allocated consecutively to groups to receive a 4 h infusion with one of three doses of inogatran. Thrombin generation and activity were measured with plasma markers at baseline, after the 4 h treatment period and 4 h later. Ischaemia was monitored using continuous vectorcardiography during the 4 h of treatment and during the subsequent 4 h after inogatran infusion had been stopped, to detect any increase in ischaemic events after the period of treatment. In addition, 12 patients received inogatran as an infusion for 72 h.. Inogatran was tolerated well. There were no adverse haemodynamic effects or allergic reactions. Minor bleeding events were detected in 37% of the patients. The biochemical and vectorcardiographic findings indicated suppression of thrombin generation after the 4 h treatment period compared with baseline. During the first 4 h after inogatran treatment, thrombin activity and episodes of ischaemia were increased compared with during the treatment period.. Inogatran was tolerated well and was safe, but its discontinuation was followed by a reactivation of thrombin activity and ischaemia. Whether this reactivation represented a rebound phenomenon, or merely resulted from the discontinuation of an effective therapy, cannot be established from the present study.

Topics: Adult; Aged; Angina, Unstable; Antithrombins; Drug Tolerance; Female; Follow-Up Studies; Glycine; Hemodynamics; Humans; Infusions, Intravenous; Male; Middle Aged; Myocardial Infarction; Partial Thromboplastin Time; Piperidines; Recurrence; Thrombin; Vectorcardiography

Ninety-five patients with suspected acute myocardial infarction were randomly allocated on admission to hospital on a double blind basis to treatment with lorcainide, a Class 1C anti-arrhythmic drug, or matching placebo. Treatment was continued for 6 weeks. Twenty-four-hour ECG tape recordings were made immediately on admission, on the sixth or seventh day after admission, and again just before the end of the treatment period. Lorcainide was shown to be an effective anti-arrhythmic agent. The study was not designed to evaluate the effect of lorcainide on survival, but there were nine deaths among the 49 patients treated with lorcainide compared with only one in the patients given placebo. These findings are consistent with the results of the First and Second Cardiac Arrhythmia Suppression trials (CAST and CAST-II). This study was carried out in 1980 but was not published at the time: it now provides an interesting example of 'publication bias'.

Topics: Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzeneacetamides; Double-Blind Method; Electrocardiography; Female; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Publishing; Survival Analysis; Time Factors

The acute haemodynamic effects of pirmenol, a new Class 1 antiarrhythmic agent, were investigated in a double-blind comparison with lidocaine and placebo. Three groups of 10 patients each received either pirmenol as a 50 mg intravenous injection followed by a 2.5 mg min-1 infusion, or lidocaine as a 75 mg injection followed by a 3 mg min-1 infusion, or placebo. Mean plasma pirmenol concentrations during the 30 min infusion period were 2.3-2.5 mg l-1, and were considered to be therapeutically effective. Compared to measurements taken during a baseline phase of 15 min duration, pirmenol increased heart rate by 10 beats min-1 (P less than 0.001) and mean arterial pressure (MAP) by 5 mmHg (P less than 0.001). It also increased systemic vascular (P less than 0.05) and pulmonary arterial resistances (P less than 0.01). Left ventricular end-diastolic pressure (LVEDP) was not increased significantly. Cardiac index and left ventricular work index remained unchanged. Lidocaine induced a comparable increase in MAP (6 mmHg; P less than 0.001) and elevated LVEDP (2.8 mmHg; P less than 0.05) and did not affect left ventricular work index. Echocardiographic left ventricular ejection fraction was reduced more by pirmenol (-0.05; P less than 0.001) than by lidocaine (-0.03; P less than 0.05), but the greater reduction may partly be explained by the increase in heart rate. Primenol did not induce excessive circulatory responses or side-effects in any patient. Intravenous administration of pirmenol results in increased heart rate and afterload but has little effect on preload. The myocardial depressant effect is relatively slight, and comparable to that of lidocaine.

Topics: Adult; Analysis of Variance; Anti-Arrhythmia Agents; Clinical Trials as Topic; Coronary Disease; Double-Blind Method; Female; Hemodynamics; Humans; Lidocaine; Male; Middle Aged; Myocardial Infarction; Piperidines

Thirty patients with frequent (greater than or equal to 30/hr) and repetitive ventricular premature beats (VPBs) unassociated with acute infarction were randomized to intravenous lorcainide (LOR) or lidocaine (LID). Following at least 2 hours of baseline Holter monitoring, patients received LOR, 2 mg/kg then 200 mg/24hr, or LID, 1 mg/kg then 2 mg/min, with rebolus if needed. Nonresponders detected by bedside telemetry were crossed over. Clinical response was 6 of 25 (24%) including two of nine crossovers with LOR and 8 of 26 (31%) including 3 of 12 crossovers with LID (p = NS). By computer analysis of 24-hour Holter monitors and asymptotic regression of success rates at hourly intervals, it was projected that greater than or equal to 80% reduction in VPBs occurred in 28% of LOR and in 25% of LID (p = NS), and complete suppression of repetitive VPBs occurred in 102% of LOR and in 92% of LID (p = NS). The mean drug levels were 405 ng/ml (range 371 to 463) with LOR and 3.4 micrograms/ml (range 2.1 to 3.6) with LID. Side effects were similar, occurring in 8 of 25 LOR trials and in 11 of 26 LID trials (p = NS). Thus, LOR and LID effectively suppress repetitive VPBs and to a lesser extent VPB frequency. However, neither drug is superior and each may be an effective alternative when resistance to the other is encountered.

Topics: Aged; Arrhythmias, Cardiac; Benzeneacetamides; Chronic Disease; Electrocardiography; Female; Humans; Infusions, Parenteral; Kinetics; Lidocaine; Male; Middle Aged; Monitoring, Physiologic; Myocardial Infarction; Piperidines; Random Allocation

The sodium content of erythrocytes from patients with essential hypertension is increased. In a double-blind, placebo-controlled study, a 5-day treatment with ketanserin, a serotonergic antagonist lowered significantly the sodium content of the red blood cells (RBC). Ouabain induces an increase of sodium content of the RBC, which is paralleled by a decrease in RBC deformability. The ouabain-dependent fraction of RBC deformability is significantly reduced after a single oral dose of ketanserin. In vitro, serotonin (5-HT) decreases RBC deformability; this effect could be antagonized by ketanserin. These data might suggest a regulating role of 5-HT in transmembrane ion fluxes.

Topics: Adult; Aged; Erythrocyte Deformability; Erythrocytes; Humans; Hypertension; Ketanserin; Middle Aged; Myocardial Infarction; Ouabain; Piperidines; Serotonin; Serotonin Antagonists; Sodium

Platelet aggregation in response to 5-hydroxytryptamine was investigated in 40 normal subjects, in 45 patients with acute myocardial infarction, and in 65 patients with peripheral arterial obstructive disease. It was found that of the 110 patients with cardiovascular disease, 40% had a biphasic irreversible platelet aggregation, whereas this phenomenon occurred in only 7.5% of the normal population. A double-blind placebo-controlled study further showed that a subacute treatment with ketanserin, a selective 5-HT2-receptor antagonist both on platelets and on vascular tissue, efficiently abolished the irreversible platelet aggregation in patients hyperreactive to 5-hydroxytryptamine. In an additional open study, including 10 patients with peripheral arterial obstructive disease, a chronic treatment with ketanserin 40 mg t.i.d. for a period of 3 months significantly suppressed the primary platelet aggregation to 5-HT at 2 X 10(-5) M and at 2 X 10(-6) M and significantly lowered the plasma beta thromboglobulin levels. Since 5-HT is a potent mediator of vasospasm, treatment with ketanserin might be of therapeutic value in atherosclerotic diseases, where platelet activation is thought to be involved.

Topics: Aged; Arterial Occlusive Diseases; beta-Thromboglobulin; Cardiovascular Diseases; Double-Blind Method; Female; Humans; Ketanserin; Male; Middle Aged; Myocardial Infarction; Piperidines; Placebos; Platelet Aggregation; Serotonin

We evaluated the hemodynamic effects of the class I antiarrhythmic flecainide in 20 patients within 18 hours of an acute myocardial infarction. Equal numbers of patients with normal (group 1) or decompensated (group 2) ventricular function were studied. Both groups received flecainide, 1 mg/kg, as an intravenous bolus over 10 minutes, followed by infusion (1.6 mg/kg/hr) over the next 120 minutes. Plasma concentrations increased linearly with the cumulative flecainide dosage in both groups. There was no difference between the groups in the plasma levels reached, which were within the recognized antiarrhythmic range for flecainide (200 to 1000 ng/ml) throughout the infusion. The hemodynamic effects of flecainide for each group were decreases in systolic blood pressure (maximum 3% fall in group 1 and 8% fall in group 2), cardiac index (9% fall in group 1 and 18% fall in group 2), stroke volume index (13% fall in group 1 and 23% fall in group 2), stroke work index (14% fall in group 1 and 27% fall in group 2), with an increased heart rate (8% rise in group 1 and 5% rise in group 2), pulmonary artery occluded pressure (27% rise in group 1 and 21% rise in group 2), and systemic vascular resistance (11% rise in group 1 and 18% rise in group 2). Diastolic and mean arterial blood pressures did not change. Our data demonstrate that flecainide induced significant cardiodepression in both groups of patients. These effects were not significantly greater in patients with adequately controlled heart failure. These data suggest that the mild negative inotropic properties of flecainide in patients with recent myocardial infarction are comparable to those described for other class I antiarrhythmics.

Topics: Adult; Aged; Anti-Arrhythmia Agents; Blood Pressure; Clinical Trials as Topic; Dose-Response Relationship, Drug; Flecainide; Heart Rate; Heart Ventricles; Hemodynamics; Humans; Infusions, Parenteral; Male; Middle Aged; Myocardial Infarction; Piperidines; Stroke Volume; Time Factors; Vascular Resistance

Non-sustained ventricular tachycardia (VT) in the late post myocardial infarction (MI) period (7-21 days) has been reported to be a predictor of sudden death. We suspected that patients with 3 beat VT on Holter monitoring in the late infarction period would demonstrate electrical instability at electrophysiologic studies. Forty-seven patients were identified as having at least 3 beat VT on Holter monitoring. Eighteen patients refused electrophysiologic studies or were not referred by their attending physician. The mean ejection fraction of this group was 43 +/- 16%. Eight patients have died, 3 sudden deaths in 13 +/- 5 months, a 17% incidence of sudden death. Twenty-nine patients underwent invasive electrophysiologic studies. Their mean ejection fraction was 37 +/- 7%, and 28 had inducible, 18 sustained ventricular tachycardia and 10 non-sustained VT. No complications were noted with electrophysiological testing in the post infarction patients. Using programmed electrical stimulation studies an effective antiarrhythmic agent preventing VT induction (usually experimental) could be found for each patient. After a mean follow-up of 12.5 +/- 4 months, the patient without inducible VT is alive and 26 of the 28 "inducible" patients are alive and well. Two patients died, one of stroke and one due to pump failure following a second MI. No sudden deaths were observed in this group. Two patients had breakthrough arrhythmias and were treated by alternative antiarrhythmic therapy that was also effective at the initial electrophysiologic studies. Thus, PES studies post MI are safe and may be an effective way to assess therapy for patients in the early post MI period, identified at high risk for sudden death.

Topics: Aged; Anti-Arrhythmia Agents; Benzeneacetamides; Cardiac Pacing, Artificial; Clinical Trials as Topic; Electrocardiography; Female; Heart Rate; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Tachycardia

Lorcainide, a new class I antiarrhythmic agent, was administered intravenously to eight patients with acute myocardial infarction for 24 hours, and thereafter given by mouth, 200 mg daily for ten days. Ten control infarction patients were given lidocaine 3 mg/min during the first 24 hours and the oral betablocking agent, pindolol, for the following ten days. The two groups were comparable with respect to age, sex, onset-admission interval, and site and size of infarction. Ventricular premature beats were monitored with a 24-hour continuous ECG recording on days 1, 6 and 10. Complex ventricular premature beats were common during the first 24 hours of infarction; their occurrence and severity were similar in both groups, as judged by the Lown grading system. The plasma levels of lorcainide after the 24-hour infusion ranged 72-144 ng/ml (mean 95 ng/ml). On the sixth day, 12 hours after previous oral dose, lorcainide plasma levels ranged 11-82 ng/ml (mean 42 ng/ml). No major adverse effects were noticed, mild insomnia being the most disturbing reaction. It is concluded that lorcainide is an acceptable alternative to lidocaine in the treatment of ventricular arrhythmias in the acute stage of myocardial infarction. It has the advantage of being effective by oral route, too.

Topics: Administration, Oral; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzeneacetamides; Clinical Trials as Topic; Female; Humans; Infusions, Parenteral; Lidocaine; Male; Middle Aged; Myocardial Infarction; Pindolol; Piperidines; Random Allocation

In 12 patients with coronary artery disease, 11 of them with previous myocardial infarction, the antiarrhythmic effects of orally administered flecainide (F.), mexiletine (M.) and propafenone (P.) were examined. The doses amounted to 400 mg F., 600 mg M., and 900 mg P. daily. The administration was made randomized with a change between placebo and verum periods with a duration of 3 respectively 4 days. The 3 antiarrhythmic agents reduced significantly the number of ventricular premature beats (VPB), the reduction of VPB amounted to 94.2% (F.), 80.2% (P.), and 52.8% M.). Repetitive VPB were reduced about 98.8 % (F.), 96.8% (P.) and 83.33% (M.). The Lown-Index diminished by about 1.45 classes (F.) 1.18 classes (P.) respectively 0.55 classes (M.). A complete suppression of VPB was obtained only in one patient under medication with F. F. and P. lengthened the duration of P, PQ and QRS, whereas M. did not affect these parameters. Heart rate and QT remained unchanged. Subjective side-effects of the 3 agents were similar. Without of the influence on the ECG, objective side effects were missed. The long plasma half-life of F. (19.0 +/- 5.2 h) guarantees an antiarrhythmic effect over a period of 24 hours if the substance is administered twice daily. The large variance of plasma half-life can cause some difficulties in the finding of individually required dose of F.

Topics: Adult; Aged; Anti-Arrhythmia Agents; Cardiac Complexes, Premature; Coronary Disease; Electrocardiography; Flecainide; Half-Life; Heart Rate; Heart Ventricles; Humans; Mexiletine; Middle Aged; Myocardial Infarction; Piperidines; Propafenone; Propiophenones

In vitro animal studies suggest melperone, a neuroleptic butyrophenone, to be a type III antiarrhythmic drug according to the classification of Vaughan Williams. It has no negative inotropic effect on cardiac muscle. A double-blind trial of 3 hours' duration was carried out with melperone and placebo in 26 patients admitted to the CCU with suspected acute myocardial infarction (AMI) and ventricular arrhythmias. Melperone, 50 mg i.v., was superior to placebo in reducing the total number of ventricular ectopic beats (VEB) as well as the number of minutes with either frequent, multifocal, R-on-T-type or runs of VEB. The reduction became statistically significant in the second treatment hour in patients with definite AMI. Melperone induced sedation and reduction of systemic BP in most of the patients. Two patients with low initial systolic BP achieved a further reduction and had BP levels below 90 mmHg. Two patients experienced minor side-effects. In conclusion, melperone administered in large i.v. doses to patients with AMI induced sedation, acute BP reduction and some reduction of ventricular arrhythmia. X

Topics: Aged; Arrhythmias, Cardiac; Blood Pressure; Butyrophenones; Double-Blind Method; Female; Heart Rate; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Placebos

The effectiveness of perhexiline maleate in the suppression of ventricular ectopic activity has been studied in 10 patients after myocardial infarction. Before treatment all patients exhibited frequent ectopic beats, i.e. more than 8 per hour. Numerous Holter magnetic tape recordings were made over a 9 - 10-month period of treatment. During the entire period of monitoring significant suppression of ectopic activity was observed in 5 patients and transient suppression in 4, of whom 3 subsequently showed a transient increase. The drug was discontinued in 1 patient because of nausea, anorexia and weight loss. No other adverse effects were encountered.

Topics: Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Clinical Trials as Topic; Humans; Male; Middle Aged; Myocardial Infarction; Perhexiline; Piperidines; Ventricular Fibrillation

The antianginal effect of perhexiline was evaluated in a placebo-controlled double-blind study of 20 patients with stable angina pectoris. Only patients with documented myocardial infarction of more than 6 months' standing and with ST-segment depression on exercise were admitted to the study. Objective parameters of bicycle stress tests at a submaximum level of 50 watts and a maximum exercise level were evaluated. Subjective data such as nitroglycerin consumption and incidence of anginal attacks per week were obtained from the patients' self-maintained records. No negative chronotropic effect of perhexiline was found at rest. At a submaximum exercise level with unchanged double-product, a significantly lower heart rate (p less than 0.05) and a significant reduction in ST-segment depression were observed in comparison with the placebo. At maximum exercise level an increase in exercise tolerance of 8.1% and in aerobic capacity of 8.3% resulted in a significant increase in the double-product (p less than 0.01), with a shift in the blood pressure/heart rate ratio. Discontinuation of exercise occurred at the same heart rate, but at a markedly higher level of exercise attainment. Heart rate on exercise proved to be the most valuable parameter in this study for the evaluation of the aerobic capacity of the individual patient. Nitroglycerin consumption and frequency of anginal attacks per week were reduced, but were not of statistical significance. Side-effects occurred in 6 patients, but these did not require termination or reduction of medication. The selective effect on heart rate during exercise opens a new field of application for perhexiline in comparison with beta-blocking agents.

Topics: Adult; Aged; Angina Pectoris; Double-Blind Method; Exercise Test; Heart Rate; Humans; Middle Aged; Myocardial Infarction; Perhexiline; Physical Exertion; Piperidines

Myocardial infarction (MI) eventually exacerbates inflammatory response due to the release of inflammatory and pro-inflammatory factors. The aim of this study is to explore the protective efficacy of piperine supplementation against the inflammatory response in isoproterenol (ISO)-induced MI. Masson Trichome staining was executed to determine myocardial tissue architecture. Immunohistochemistry was performed for IL-6, TNF-α. RT-PCR studies were performed to ascertain the gene expression of IL-6, TNF-α, iNOS, eNOS, MMP-2, MMP-9, and collagen-III. Western blotting was performed to determine expression of HIF-1α, VEGF, Nrf-2, NF-ƙB, Cox-2, p-38, phospho-p38, ERK-1/2, phospho-ERK-1/2, and collagen-I. HIF-1α, VEGF, and iNOS expression were significantly upregulated with concomitant decline in eNOS expression in the heart myocardial tissue of rats received ISO alone whereas piperine pretreatment prevented these changes in ISO administered rats. Current results revealed ROS-mediated activation of MAPKs, namely, p-p38, p-ERK1/2 in the heart tissue of ISO administered group. Piperine pretreatment significantly prevented these changes in ISO treated group. NF-κB is involved in the modulation of gene expressions responsible for tissue repair. ISO-induced NF-κB-p65 expression was significantly reduced in the group pretreated with piperine and mitigated extent of myocardial inflammation. A significant increase in cardiac fibrosis upon ISO treatment was reported due to the increased hydroxyproline content, MMP-2 & 9 and upregulation of collagen-I protein compared to control group. All these cardiac hypertrophy markers were decreased in 'piperine pretreated ISO administered group' compared to group received ISO injection. Current findings concluded that piperine as a nutritional intervention could prevent inflammation of myocardium in ISO-induced MI.

Topics: Adrenergic beta-Agonists; Alkaloids; Animals; Benzodioxoles; Cardiomegaly; Cytokines; Endothelium; Fibrosis; Inflammation; Isoproterenol; Male; Myocardial Infarction; Myocardium; Piperidines; Polyunsaturated Alkamides; Rats; Rats, Wistar; Signal Transduction; Transcription Factor RelA

Tofacitinib is an oral JAK inhibitor for the treatment of rheumatoid arthritis (RA). This study was undertaken to evaluate the risk of major adverse cardiovascular events (MACE) in patients with RA receiving tofacitinib.. Data were pooled from patients with moderately to severely active RA receiving ≥1 tofacitinib dose in 6 phase III and 2 long-term extension studies over 7 years. MACE (myocardial infarction, stroke, cardiovascular death) were independently adjudicated. Cox regression models were used to evaluate associations between baseline variables and time to first MACE. Following 24 weeks of tofacitinib, changes in variables and time to future MACE were evaluated after adjusment for age, baseline values, and time-varying tofacitinib dose. Hazard ratios and 95% confidence intervals were calculated.. Fifty-two MACE occurred in 4,076 patients over 12,873 patient-years of exposure (incidence rate 0.4 patients with events per 100 patient-years). In univariable analyses of baseline variables, traditional cardiovascular risk factors and glucocorticoid and statin use were associated with MACE risk; disease activity and inflammation measures were not. In subsequent multivariable analyses, baseline age, hypertension, and the total cholesterol to high-density lipoprotein (HDL) cholesterol ratio remained significantly associated with risk of MACE. After 24 weeks of treatment, an increase in HDL cholesterol and a decrease in the total to HDL cholesterol were associated with decreased MACE risk; changes in total cholesterol, low-density lipoprotein (LDL) cholesterol, and disease activity measures were not. Increased erythrocyte sedimentation rates trended with increased future MACE risk.. In this post hoc analysis, after 24 weeks of tofacitinib treatment, increased HDL cholesterol, but not increased LDL cholesterol or total cholesterol, appeared to be associated with lower future MACE risk. Further data are needed to test the cardiovascular safety of tofacitinib.

Topics: Aged; Arthritis, Rheumatoid; Blood Sedimentation; Cardiovascular Diseases; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Clinical Trials, Phase III as Topic; Female; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Piperidines; Proportional Hazards Models; Protein Kinase Inhibitors; Pyrimidines; Pyrroles; Risk Factors; Stroke; Treatment Outcome

Exercise training (ET) is a safe and efficacious therapeutic approach for myocardial infarction (MI). Given the numerous benefits of exercise, exercise-induced mediators may be promising treatment targets for MI. C57BL/6 mice were fed 1-trifluoromethoxyphenyl-3-(1-propionylpiperidine-4-yl) urea (TPPU), a novel soluble epoxide hydrolase inhibitor (sEHI), to increase epoxyeicosatrienoic acid (EET) levels, for 1 week before undergoing MI surgery. After 1-week recovery, the mice followed a prescribed exercise programme. Bone marrow-derived endothelial progenitor cells (EPCs) were isolated from the mice after 4 weeks of exercise and cultured for 7 days. Angiogenesis around the ischaemic area, EPC functions, and the expression of microRNA-126 (miR-126) and its target gene Spred1 were measured. The results were confirmed in vitro by adding TPPU to EPC culture medium. ET significantly increased serum EET levels and promoted angiogenesis after MI. TPPU enhanced the effects of ET to reduce the infarct area and improve cardiac function after MI. ET increased EPC function and miR-126 expression, which were further enhanced by TPPU, while Spred1 expression was significantly down-regulated. Additionally, the protein kinase B/glycogen synthase kinase 3β (AKT/GSK3β) signalling pathway was activated after the administration of TPPU. EETs are a potential mediator of exercise-induced cardioprotection in mice after MI. TPPU enhances exercise-induced cardiac recovery in mice after MI by increasing EET levels and promoting angiogenesis around the ischaemic area.

Topics: 8,11,14-Eicosatrienoic Acid; Adaptor Proteins, Signal Transducing; Animals; Bone Marrow Cells; Cardiotonic Agents; Coronary Vessels; Disease Models, Animal; Endothelial Progenitor Cells; Enzyme Inhibitors; Epoxide Hydrolases; Gene Expression Regulation; Glycogen Synthase Kinase 3 beta; Male; Mice; Mice, Inbred C57BL; MicroRNAs; Myocardial Infarction; Neovascularization, Physiologic; Phenylurea Compounds; Physical Conditioning, Animal; Piperidines; Primary Cell Culture; Proto-Oncogene Proteins c-akt; Repressor Proteins; Signal Transduction

Myocardial infarction due to ischemia accounts for majority of deaths among cardiovascular disorders. Isoproterenol (ISO) induced myocardial infarction and the protection offered by piperine was investigated in the present report. Lipid profile analysis by determining the levels of cholesterol, phospholipids, triglycerides and lipoproteins in serum and heart tissues showed anti-dyslipidemic action of piperine against ISO induced myocardial injury by modulating the ISO induced altered lipid profiles, maintaining to near control values. ISO treatment increased TBARS levels, PCC, serum markers of heart, depleted antioxidant status (GSH, SOD, CAT, GPx and GST) in tissues and, total, protein- and non-protein-sulfhydryl levels in serum and heart tissues. Piperine pre-treatment decreased the levels of serum markers, lipid peroxidation and PCC with increased antioxidant status in the heart tissues of ISO administered rats. Increased levels of the glycoprotein components in serum and decreased levels in heart tissues upon ISO administration were restored to near normal levels by piperine pre-treatment. Our present reports also showed the modulatory effect of piperine on membrane bound ATPase's showing protection against ISO induced changes in membrane fluidity. The present study proved piperine as a potent therapeutic agent with its antioxidant and anti-dyslipidemic action against ISO induced myocardial infarction.

Topics: Alkaloids; Animals; Antioxidants; Benzodioxoles; Biomarkers; Heart; Isoproterenol; Lipid Peroxidation; Male; Myocardial Infarction; Myocardial Ischemia; Myocardium; Oxidative Stress; Piperidines; Polyunsaturated Alkamides; Rats; Rats, Wistar

We designed a study to evaluate the cardioprotective effect of two soluble epoxide hydrolase (sEH) inhibitors, 1-(1-propanoylpiperidin-4-yl)-3-(4-trifluoromethoxy)phenyl)urea (TPPU) and trans-4-{4-[3-(4-trifluoromethoxyphenyl)-ureido]cyclohexyloxy}benzoic acid (t-TUCB), in ischemia-reperfusion (IR) model.. Cardioprotective effects of the sEH inhibitors were evaluated against IR-induced myocardial damage in hearts from normal, hypertensive, and diabetic rats using Langendorff's apparatus. In addition, the effect of sEH inhibitors on endothelial function was evaluated in vitro and ex vivo using isolated rat thoracic aorta.. Ischemia-reperfusion (IR) increased the myocardial damage in hearts from normal rats. IR-induced myocardial damage was augmented in hearts isolated from hypertensive and diabetic rats. Myocardial damage as evident from increase in the activities of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) in heart perfusate was associated with significant decrease in the heart rate and developed tension, and increase in the resting tension in isolated heart. Both sEH inhibitors protected the heart in normal, hypertensive, and diabetic rats subjected to IR injury. The sEH inhibitor t-TUCB relaxed phenylephrine precontracted aorta from normal rats. Relaxant effect of acetylcholine (ACh) was reduced in aortas from diabetic and hypertensive rats compared to normal rats. Pretreatment of sEH inhibitors to diabetic and hypertensive rats increased relaxant effect of ACh on aortas isolated from these rats.. Prophylactic treatment with sEH inhibitors decreased myocardial damage due to IR, hypertension and diabetes, and decreased endothelial dysfunction created by diabetes and hypertension. Therefore, inhibitors of sEH are useful probes to study cardiovascular pathology, and inhibition of the sEH is a potential approach in the management of IR-induced cardiac damage and endothelial dysfunction-related cardiovascular disorders.

Topics: Animals; Aorta, Thoracic; Benzoates; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Enzyme Inhibitors; Epoxide Hydrolases; Heart Rate; Hypertension; Isolated Heart Preparation; Male; Myocardial Contraction; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Phenylurea Compounds; Piperidines; Rats, Wistar; Vasodilation

Remifentanil preconditioning attenuates myocardial ischemia reperfusion injury, but the underlying mechanism is incompletely understood. The Janus activated kinase-2 (JAK2)/signal transducers and activators of transcription-3 (STAT3) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways are critical in both ischemic and pharmacologic preconditioning cardioprotection, which involve the inactivation of glycogen synthase kinase-3β. We hypothesized that remifentanil preconditioning confers cardioprotection via the JAK2/STAT3 and/or PI3K/Akt activation-mediated glycogen synthase kinase-3β inhibition.. Pharmacologic intervention.. Research laboratory.. Male Sprague-Dawley rats.. In vivo and in vitro treatments.. Male Sprague-Dawley rats (n = 6 per group) were sham operated or subjected to myocardial ischemia reperfusion injury. The JAK2 inhibitor AG490 (3 mg/kg), the PI3K inhibitor wortmannin (15 μg/kg), or the glycogen synthase kinase-3β inhibitor SB216763 (600 μg/kg) were given before inducing in vivo myocardial ischemia reperfusion injury achieved by occluding coronary artery for 30 minutes followed by 120 minutes of reperfusion in the absence or presence of remifentanil preconditioning (6 μg/kg/min). Also, isolated rat hearts were Langendorff perfused and subjected to 30 minutes of global ischemia and 120 minutes of reperfusion without or with remifentanil preconditioning (100 ng/mL) in the presence or absence of AG490 and/or SB216763. Isolated rat cardiomyocytes and H9C2 cells were subjected to hypoxia/reoxygenation alone or in combination with AG490 (100 μM), wortmannin (100 nM), or SB216763 (3 μM) without or with remifentanil preconditioning (2.5 μM). Remifentanil preconditioning reduced postischemic myocardial infarction and hemodynamic dysfunction induced by myocardial ischemia reperfusion injury concomitant with increased phosphorylation of STAT3 at tyr-705 (p-STAT3) and glycogen synthase kinase-3β but not Akt. AG490 but not wortmannin cancelled remifentanil preconditioning cardioprotection, and SB216763 restored it despite the presence of AG490. In Langendorff-perfused hearts, AG490-mediated cancellation of remifentanil preconditioning cardioprotection in attenuating postischemic myocardial infarction and creatinine kinase-MB release was reverted by concomitant administration of SB216763. Remifentanil preconditioning also attenuated posthypoxic cardiomyocyte injury and increased p-STAT3 and glycogen synthase kinase-3β in isolated primary cardiomyocytes and H9C2 cells. STAT3 gene knockdown with specific synthetic RNA cancelled remifentanil preconditioning cardioprotection, whereas glycogen synthase kinase-3β gene knockdown, which per se did not affect STAT3 under hypoxia/reoxygenation condition, preserved remifentanil preconditioning cardioprotection regardless of STAT3 abrogation.. Remifentanil preconditioning confers cardioprotection primarily via activation of JAK2/STAT3 signaling that can function independent of PI3K/Akt activation. Glycogen synthase kinase-3β is a critical downstream effector of remifentanil preconditioning cardioprotection.

Topics: Animals; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Ischemic Preconditioning; Janus Kinase 2; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocytes, Cardiac; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Piperidines; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Remifentanil; Signal Transduction; STAT3 Transcription Factor; Ventricular Function, Left

The purpose of this study was to determine whether there is a cross-talk between opioid receptors (OPRs) and adenosine receptors (ADRs) in remifentanil preconditioning (R-Pre) and, if so, to investigate the types of ADRs involved in the cross-talk. Isolated rat hearts received 30 min of regional ischemia followed by 2 hr of reperfusion. OPR and ADR antagonists were perfused from 10 min before R-Pre until the end of R-Pre. The heart rate, left ventricular developed pressure (LVDP),velocity of contraction (+dP/dtmax), and coronary flow (CF) were recorded. The area at risk and area of necrosis were measured. After reperfusion, the LVDP, +dP/dtmax,and CF showed a significant increase in the R-Pre group compared with the control group (no intervention before or after regional ischemia). These increases in the R-Pre group were blocked by naloxone, a nonspecific ADR antagonist, an A1 ADR antagonist, and an A2B ADR antagonist. The infarct size was reduced significantly in the R-Pre group compared with the control group. The infarct-reducing effect in the R-Pre group was blocked by naloxone, the nonspecific ADR antagonist, the A1 ADR antagonist, and the A2B ADR antagonist. The results of this study demonstrate that there is cross-talk between ADRs and OPRs in R-Pre and that A1 ADR and A2B ADR appear to be involved in the cross-talk.

Topics: Adenosine; Analgesics, Opioid; Animals; Coronary Circulation; Heart; Ischemic Preconditioning; Male; Myocardial Contraction; Myocardial Infarction; Piperidines; Rats; Rats, Sprague-Dawley; Receptor, Adenosine A2A; Receptor, Adenosine A2B; Receptors, Opioid; Remifentanil; Reperfusion Injury; Time Factors; Ventricular Function, Left

Topics: Acute Coronary Syndrome; Angina, Unstable; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Female; Glucagon-Like Peptide-1 Receptor; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Peptides; Piperidines; Uracil

Myocardial infarction is an alarming health issue, needs great attention. The present study investigated the role of histamine-H3 receptor (H3R) agonist imetit in relationship to sympathetic and renin angiotensin system in Wistar rats.. Subcutaneous injection of isoproterenol (85 mg/kg) on last 2 consecutive days in per se group and 7 days treatment of different groups at 24 h interval induced myocardial infarction in Wistar rats. H3R agonist imetit (10 mg/kg), H3R antagonist thioperamide (5 mg/kg), losartan (10 mg/kg) were administered orally to evaluate imetit's cardioprotective potential effect by measuring plasma cardiac antioxidant markers, angiotensin II, norepinephrine levels and histopathological analysis.. Isoproterenol significantly elevated the angiotensin II and norepinephrine levels in rat plasma. This study revealed that pre-treatment with imetit similar to losartan attenuated norepinephrine and angiotensin II levels whereas thioperamide showed its antagonistic effect by diminishing imetit's effects. Furthermore, its protective effect was confirmed by restoration of cardiac antioxidant markers and histopathological improvement of myocardium integrity.. This study confirm imetit's cardioprotective potential and also reveals renin angiotensin system, sympathetic system and H3R correlation in isoproterenol induced toxicity in rats. However, molecular studies must be warranted to prove the role of H3R in myocardial infarction.

Topics: Angiotensin II; Animals; Antioxidants; Cardiotonic Agents; Histamine Agonists; Histamine H3 Antagonists; Imidazoles; Isoproterenol; Losartan; Male; Myocardial Infarction; Myocardium; Norepinephrine; Piperidines; Rats; Renin-Angiotensin System; Sympathetic Nervous System; Thiourea

Myocardial infarction (MI) is defined as the deprivation of the myocardial tissue of oxygen and nutrients, resulting in the induction of inflammation and apoptosis of the cardiomyocytes. Poly (ADP‑ribose) polymerase 1 (PARP1) is a nuclear enzyme closely associated with MI, that can be activated by DNA damage. Inducible nitric oxide synthase (iNOS) is a critical enzyme among the inflammatory cytokines. The present study aimed to investigate the underlying mechanism of the protective effects of PARP1 and iNOS inhibitor against MI, in rats. A total of 40 male Wistar rats were divided into four groups. The rats were anesthetized with sodium pentobarbital (50 mg/kg), and the left anterior descending coronary artery was occluded by ligation, using a 6‑0 polypropylene monofilament suture, at the left atrial apex, in order to induce MI. The rats from each group received an abdominal injection of either dimethylsulfoxide (100 µl, for MI group); PARP‑1 inhibitor, 3,4‑dihydro‑5‑[4‑(1‑piperidinyl)butoxy]‑1(2H)‑ isoquinolinone (DPQ; 10 mg/kg); or iNOS inhibitor, N‑(1‑naphthyl)ethylenediamine dihydrochloride (1400W; 10 mg/kg). The hearts were harvested from the rats after four weeks. Inhibition of PARP and iNOS activity improved heart function, as determined by serial echocardiography. The rate of apoptosis, as determined by a terminal deoxynucleotidyl‑transferase‑mediated dUTP nick end labeling assay, was reduced by 39.71 and 39.00% in the DPQ and 1400W groups, respectively, and this was accompanied by the downregulated expression of cleaved caspase‑3 and PARP1. Effective inhibition of PARP and iNOS, by DPQ and 1400W, was detected by western blotting and immunofluorescence, and was shown to repress O2‑ and nitrotyrosine levels, following MI. The present study confirmed that inhibition of PARP1 and iNOS was able to protect against ischemic myocardial damage, by reducing the levels of apoptosis.

Topics: Amidines; Animals; Apoptosis; Benzylamines; Cardiotonic Agents; Caspase 3; Disease Models, Animal; Enzyme Inhibitors; Isoquinolines; Male; Myocardial Infarction; Myocardium; Nitric Oxide Synthase Type II; Piperidines; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Rats; Ventricular Function

Metformin is the first-line treatment for most patients with type 2 diabetes but many patients need additional treatment with insulin secretagogues (IS) to achieve glycemic control. We aimed to compare mortality and cardiovascular risk among users of metformin in combination with pharmacologically different ISs.. Using nationwide administrative Danish registries, we followed all individuals without prior stroke or myocardial infarction who initiated metformin and an IS from 1997 through 2009. Rate ratios (RR) of all-cause mortality, cardiovascular death, and a composite of myocardial infarction, stroke, or cardiovascular death were compared between user groups using time-dependent multivariable Poisson regression models. The most common combination, glimepiride+metformin, was used as reference.. A total of 56,827 patients were included, 56% male, the mean age was 61 ± 12.5 years, and median duration of prior monotherapy was 2.2 (inter quartile range 0.5-4.5) years. Crude incidence rates of mortality for combinations of ISs with metformin were; 15.4 (repaglinide), 28.1 (glipizide), 23.7 (glibenclamide), 21.1 (gliclazide), 20.7 (glimepiride), 27.7 (tolbutamide) deaths per 1000 person years. In adjusted analysis, the associated mortality risk was similar for users of gliclazide+metformin (RR=1.01 [0.88-1.15]), repaglinide+metformin (RR=0.81 [0.62-1.05]), glibenclamide+metformin (RR=0.98 [0.87-1.10]), and tolbutamide+metformin (RR=1.04 [0.85-1.28]). Users of glipizide+metformin was associated with increased all-cause mortality (RR=1.16 [1.02-1.32], p=0.02), cardiovascular death (RR=1.21 [1.01-1.46], p=0.04), and the combined endpoint (RR=1.20 [1.06-1.36, p=0.005).. Most ISs in combination with metformin were associated with similar mortality and cardiovascular risk. Whether glipizide is associated with increased risk compared with other ISs when used in combinations with metformin warrants further study.

Topics: Aged; Carbamates; Cardiovascular Diseases; Denmark; Diabetes Mellitus, Type 2; Drug Therapy, Combination; Female; Gliclazide; Glipizide; Glyburide; Humans; Hypoglycemic Agents; Male; Metformin; Middle Aged; Morbidity; Myocardial Infarction; Piperidines; Registries; Retrospective Studies; Risk Factors; Stroke; Sulfonylurea Compounds; Tolbutamide

Topics: Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzeneacetamides; Female; Humans; Male; Myocardial Infarction; Piperidines

Although there is a possibility of cross talk between opioid and adenosine signaling pathways in the ischemic-reperfused myocardium, it is not clear that an ultra-short-acting opioid receptor agonist remifentanil-induced postconditioning (RPostC) has cross talk with adenosine receptor (ADR). The purpose of this study was to determine whether there is cross talk with ADR in RPostC.. Isolated rat hearts were subjected to 30 min of regional ischemia and 2 h of reperfusion. RPostC was induced by 100 ng/mL of remifentanil perfusion, 5 min before reperfusion, followed by 5 min of reperfusion. The nonspecific opioid receptor antagonist naloxone (NAL) and the nonspecific ADR antagonist 8-(p-sulfophenyl) theophylline hydrate (8-SPT) were perfused for a 20-min period, 10 min before RPostC to the end of RPostC. Western blot analysis was performed to detect phospho-ERK1/2 in cultured cardiomyocytes.. In cultured cardiomyocytes, remifentanil incubation significantly increased the phosphorylation of ERK1/2 and this effect was blocked by both NAL and 8-SPT (P < 0.01 and P < 0.05, respectively). RPostC significantly reduced infarct size over ischemic area at risk from 34.1 ± 10.5% to 16.6 ± 7.5% (P < 0.05 versus control). The infarct-limitation effect of RPostC was reversed by both NAL (33.8 ± 13.0%, P < 0.05) and 8-SPT (35.7 ± 14.5%, P < 0.01).. This study strongly implies that the intracellular signaling pathways of cardioprotection by RPostC has cross talk with ADR in the ischemic-reperfused myocardium.

Topics: Analgesics, Opioid; Animals; Biometry; Blotting, Western; Cells, Cultured; Coronary Circulation; Heart Function Tests; In Vitro Techniques; Ischemic Postconditioning; Male; Myocardial Infarction; Myocardium; Piperidines; Purinergic P1 Receptor Agonists; Random Allocation; Rats, Sprague-Dawley; Receptor Cross-Talk; Receptors, Purinergic P1; Remifentanil; Reperfusion Injury

Topics: Animals; Heart Failure; Indans; Losartan; Myocardial Infarction; Piperidines

Although OPC-28326, 4-(N-methyl-2-phenylethylamino)-1-(3,5-dimethyl-4-propionyl-aminobenzoyl) piperidine hydrochloride monohydrate, was developed as a selective peripheral vasodilator with α2-adrenergic antagonist properties, it also reportedly exhibits angiogenic activity in an ischemic leg model. The purpose of this study was to examine the effect of OPC-28326 on the architectural dynamics and function of the infarcted left ventricle during the chronic stage of myocardial infarction. Myocardial infarction was induced in male C3H/He mice, after which the mice were randomly assigned into two groups: a control group receiving a normal diet and an OPC group whose diet contained 0.05% OPC-28326. The survival rate among the mice (n = 18 in each group) 4 wk postinfarction was significantly greater in the OPC than control group (83 vs. 44%; P < 0.05), and left ventricular remodeling and dysfunction were significantly mitigated. Histologically, infarct wall thickness was significantly greater in the OPC group, due in part to an abundance of nonmyocyte components, including blood vessels and myofibroblasts. Five days postinfarction, Ki-67-positive proliferating cells were more abundant in the granulation tissue in the OPC group, and there were fewer apoptotic cells. These effects were accompanied by activation of myocardial Akt and endothelial nitric oxide synthase. Hypoxia within the infarct issue, assessed using pimonidazole staining, was markedly attenuated in the OPC group. In summary, OPC-28326 increased the nonmyocyte population in infarct tissue by increasing proliferation and reducing apoptosis, thereby altering the tissue dynamics such that wall stress was reduced, which might have contributed to a mitigation of postinfarction cardiac remodeling and dysfunction.

Topics: Angiogenesis Inducing Agents; Aniline Compounds; Animals; Cell Proliferation; Heart; Ki-67 Antigen; Mice; Myocardial Infarction; Myocardium; Myofibroblasts; Nitric Oxide Synthase Type III; Piperidines; Proto-Oncogene Proteins c-akt; Survival Rate; Vasodilator Agents; Ventricular Dysfunction, Left; Ventricular Remodeling

Carotid endarterectomy is the most effective treatment for reducing the risk of stroke in patients with significant carotid stenosis. Few studies have focused on the failure rate of regional anesthesia.. Data of all patients undergoing carotid endarterectomy (June 2009 to December 2014) in a single center were collected. Combined deep and superficial cervical plexus block or superficial plexus block alone was used according to the attending anesthesiologist's choice and the patient's characteristics (eg, dual antiplatelet or anticoagulation therapy). Intraoperative remifentanil (0.025-0.05 μg/kg/min) was administered to maintain an adequate level of comfort, responsiveness, and cooperation. General anesthesia was planned only in the case of major contraindications or the patient's refusal of locoregional anesthesia. The primary end point of our study was the incidence of intraoperative conversion from locoregional to general anesthesia.. A total of 2463 carotid endarterectomies were included in the analysis. Regional anesthesia was initially chosen in 2439 patients, whereas 24 patients received planned general anesthesia. In seven cases, regional anesthesia was converted to general anesthesia because of severe agitation of the patient (before clamping in four cases, after carotid clamping in two cases, and after declamping in one case). A shunt was used in 302 patients (12.3%) because of neurologic deterioration at the carotid clamping test. Intraoperative complications were emergent repeated surgical procedures in 13 cases (0.53%) because of acute neurologic deterioration, 1 intraoperative acute myocardial infarction (0.04%), and 3 cases (0.04%) of hemodynamically relevant supraventricular tachyarrhythmia. No intraoperative death occurred. In-hospital mortality was 0.12% (three patients). Major stroke occurred in 23 patients (0.93%); minor stroke occurred in 16 patients (0.65%). The combined stroke and death rate was 1.62% (40 patients).. In our practice, carotid endarterectomy under regional anesthesia is safe and associated with a very low rate of conversion to general anesthesia.

Topics: Analgesics, Opioid; Anesthesia, General; Carotid Stenosis; Cerebrovascular Disorders; Cervical Plexus Block; Endarterectomy, Carotid; Hospital Mortality; Humans; Hypnotics and Sedatives; Italy; Myocardial Infarction; Piperidines; Remifentanil; Retrospective Studies; Risk Assessment; Risk Factors; Severity of Illness Index; Tachycardia, Supraventricular; Time Factors; Treatment Outcome

Topics: Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzeneacetamides; Evidence-Based Medicine; Humans; Myocardial Infarction; Piperidines; Publication Bias

Topics: Adamantane; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

Topics: Angina, Unstable; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

In 2008, the US FDA required all new glucose-lowering therapies to show cardiovascular safety, and this applies to the dipeptidyl peptidase-4 inhibitors ('gliptins').. The cardiovascular safety trials of saxagliptin and alogliptin have recently been published and are the subject of this evaluation.. The Saxagliptin Assessment of Vascular Outcomes Recorded in Patients with Diabetes Mellitus - Thrombolysis in Myocardial Infarction 53 trial and Examination of Cardiovascular Outcomes with Alogliptin versus Standard of Care were both multicentre, randomised, double-blind, placebo-controlled, Phase IV clinical trials. These trials showed that saxagliptin and alogliptin did not increase the primary end point, which was a composite of cardiovascular outcomes that did not include hospitalisations for heart failure. However, saxagliptin significantly increased hospitalisation for heart failure, which was a component of the secondary end point. The effect of alogliptin on hospitalisations for heart failure has not been reported. Neither agent improved cardiovascular outcomes. As there is no published evidence of improved outcomes with gliptins, it is unclear to us why these agents are so widely available for use. We suggest that the use of gliptins be restricted to Phase IV clinical trials until such time as cardiovascular safety and benefits/superiority are clearly established.

Topics: Adamantane; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

Topics: Adamantane; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

Modulation of vagal tone using electrical vagal nerve stimulation or pharmacological acetylcholinesterase inhibition by donepezil exerts beneficial effects in an animal model of chronic heart failure (CHF). Considering different treatment mechanisms underlying renin-angiotensin system (RAS) suppression and parasympathetic activation, we hypothesized that parasympathetic activation together with RAS inhibition could attenuate CHF progression. To test this hypothesis, we investigated the therapeutic effects of a combination of donepezil and losartan in CHF rats with extensive myocardial infarction (MI).. Rats (n = 85) that had survived extensive MI were implanted with a blood pressure transmitter and were randomly assigned to receive either a combination of donepezil and losartan (DLT group) or losartan alone (LT group). Compared with the LT group, the DLT group showed a significantly lower heart rate without hypotension. DLT therapy further improved 280-day overall survival relative to the LT group (31% vs. 8%, P = 0.022) by preventing cardiac dysfunction (LV dP/dtmax , 4064 ± 170 vs. 3430 ± 117 mmHg/s, P < 0.01; LV end-diastolic pressure, 17 ± 2 vs. 22 ± 2 mmHg, P < 0.05). DLT therapy was also associated with lower plasma BNP and catecholamine levels, lower cardiac angiotensin II concentrations, and higher capillary density in the peri-infarct region.. Combined treatment with donepezil and losartan prevented the progression of cardiac dysfunction and improved the long-term survival of CHF rats with extensive MI, suggesting that this combination could be a novel pharmacotherapy for severe CHF.

Topics: Angiotensin II Type 1 Receptor Blockers; Animals; Cholinesterase Inhibitors; Chronic Disease; Disease Models, Animal; Disease Progression; Donepezil; Drug Synergism; Drug Therapy, Combination; Heart Failure; Indans; Losartan; Myocardial Infarction; Piperidines; Rats; Rats, Sprague-Dawley; Treatment Outcome; Vagus Nerve

Myocardial infarction as the most severe clinical manifestation of coronary atherosclerosis is the major cause of death in western countries. Although rupture of an atherosclerotic plaque is generally causal for this event, in recent years differential diagnoses have been discussed to further optimize diagnosis and treatment of myocardial ischemia. The "universal definition of myocardial infarction" defines five subtypes of myocardial infarction: in particular, type 2 myocardial infarction includes other diseases related to myocardial ischemia such as hyper- or hypotension, coronary artery spasms, arrhythmia, etc. Some medications for the acute therapy of migraine like triptans can lead to myocardial infarction.

Topics: Combined Modality Therapy; Drug Substitution; Female; Humans; Middle Aged; Migraine Disorders; Myocardial Infarction; Myocardial Ischemia; Piperidines; Self Medication; Substance-Related Disorders; Tryptamines

Tissue fibrosis represents one of the largest groups of diseases for which there are very few effective therapies. In the heart, myocardial infarction (MI) resulting in the loss of cardiac myocytes can culminate in adverse cardiac remodeling leading to eventual heart failure. Adverse cardiac remodeling includes myocyte hypertrophy, fibrosis, and electrical remodeling. We have previously demonstrated the beneficial effects of several potent soluble epoxide hydrolase inhibitors (sEHIs) in different models of cardiac hypertrophy and failure. Here, we directly determine the molecular mechanisms underlying the beneficial effects of sEHIs in cardiac remodeling post-MI. Treatment with a potent sEHI, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidine-4-yl)urea (TPPU), which was started 1 wk post-MI in a murine model, results in a significant improvement in cardiac function. Importantly, treatment with TPPU results in a decrease in cardiac fibrosis as quantified using histological and immunostaining techniques. Moreover, single-cell-based assays demonstrate that treatment with TPPU results in a significant decrease not only in the percentages but also the proliferative capacity of different populations of cardiac fibroblasts as well as a reduction in the migration of fibroblasts into the heart from the bone marrow. Our study provides evidence for a possible unique therapeutic strategy to reduce cardiac fibrosis and improve cardiac function post-MI.

Topics: Animals; Cell Movement; Cell Proliferation; Cytokines; Echocardiography; Epoxide Hydrolases; Fibrosis; Flow Cytometry; Mice; Myocardial Infarction; Oxylipins; Phenylurea Compounds; Piperidines; Ventricular Remodeling

The cannabinoid receptors, CB1 and CB2, are expressed in the heart, but their role under pathological conditions remains controversial. This study examined the effect of CB1 receptor blockade on cardiovascular functions after experimental MI and in experimental metabolic syndrome. MI was induced in Wistar rats by permanent ligation of the left coronary artery. Treatment with the CB1 receptor antagonist rimonabant (10 mg/kg i.p. daily) started 7 days before or 6 h after MI and continued for 6 weeks. Haemodynamic parameters were measured via echocardiography and intracardiac Samba catheter. CB1 blockade improved systolic and diastolic heart function, decreased cardiac collagen and hydroxyproline content and down-regulated TGF-β1. Additionally, rimonabant decreased arterial stiffness, normalised QRS complex duration and reduced brain natriuretic peptide levels in serum. In primary cardiac fibroblasts, rimonabant decreased MMP-9 activity and TGF-β1 expression. Furthermore, rimonabant improved depressed systolic function of spontaneously hypertensive obese rats and reduced weight gain. Blocking of CB1 receptor with rimonabant improves cardiac functions in the early and late stages after MI, decreases arterial stiffness and reduces cardiac remodelling. Rimonabant also has cardioprotective actions in rats characterised by the metabolic syndrome. Inhibition of proteolysis and TGF-β1 expression and reduced collagen content by rimonabant may attenuate destruction of the extracellular matrix and decrease fibrosis after MI.

Topics: Animals; Cannabinoid Receptor Antagonists; Cardiotonic Agents; Cells, Cultured; Collagen; Fibroblasts; Heart; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Metabolic Syndrome; Myocardial Infarction; Piperidines; Pyrazoles; Rats; Rats, Wistar; Receptor, Cannabinoid, CB1; Rimonabant; Transforming Growth Factor beta1

Vagal activation by electrical stimulation has been shown to improve the long-term survival of rats with chronic heart failure (CHF) after extensive myocardial infarction (MI). Acetylcholinesterase inhibition increases synaptic acetylcholine, and can disproportionately increase vagal tone. To develop an alternative therapy for CHF using a clinically available drug, the present study investigated whether oral donepezil, an acetylcholinesterase inhitor, could reproduce the beneficial effects of electrical vagal stimulation in rats.. At 2 weeks after ligation of the proximal left coronary artery, resulting in extensive MI, surviving rats were randomly assigned to donepezil-treated and untreated groups. Donepezil treatment started 14 days after MI significantly decreased the heart rate (325 ± 6 vs. 355 ± 10 beats/min, P<0.05) and improved 140-day survival (29% to 54%, P=0.03) by preventing pump failure (cardiac index: +29%, P<0.001; left ventricular+dp/dtmax: +18%, P<0.01; left ventricular end-diastolic pressue: -26%, P<0.01) and cardiac remodeling (biventricular weight: 2.73 ± 0.04 vs. 3.06 ± 0.08 g/kg, P<0.001). In addition, donepezil treatment lowered the levels of plasma arginine vasopressin, brain natriuretic peptide, catecholamine, and tissue pro-inflammation markers.. Oral donepezil markedly improved the long-term survival of CHF rats by preventing pump failure and cardiac remodeling, indicating that donepezil may be a new alternative therapy for CHF. 

Topics: Animals; Cholinesterase Inhibitors; Chronic Disease; Donepezil; Heart Failure; Indans; Male; Myocardial Infarction; Piperidines; Rats; Rats, Sprague-Dawley; Time Factors

Chronic administration of high dose opioids such as morphine is known to create intracellular oxidative stress via an opioid receptor dependent mechanism and this can interfere with cellular function. This study aimed at examining whether such changes can occur following short term exposure to high concentration of remifentanil, a potent short acting opioid. We conducted a experimental study using rat myocardium and systematically quantified tissue levels of superoxide anions, malondialdehyde (MDA) and nitrotyrosine following exposure to increasing duration (15 min, 1 or 2 h) or escalating doses of remifentanil (1 μg, 5 μg, 10 μg or 20 μg/kg/min). Concurrently the susceptibility of the heart to ischaemia reperfusion injury was assessed under the similar conditions. For any given duration of remifentanil infusion, there was increasing superoxide anions generated as the dose of remifentanil was increased. MDA concentrations were significantly increased when the animal was exposed to 10 μg/kg/min for 2h or 20 μg/kg/min for any duration. There was a trend towards an increased nitrotyrosine concentration with increasing dose of remifentanil, becoming significant when the dose was 20 μg/kg/min. The infarct limiting ability of remifentanil was compromised when the dihydroethidium fluorescence positive cell percentage exceeded 50%, MDA concentration greater than 2 nmol/mg of protein and nitrotyrosine content exceeding 1.5 μg/mg of protein. Short term high dose opioid exposure can induce oxidative changes seen previously only with chronic opioid use and this high oxidative stress environment corrupts the heart's sensitivity to be preconditioned by opioids.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Analgesics, Opioid; Animals; Deoxyguanosine; Dose-Response Relationship, Drug; Hemodynamics; Ischemic Preconditioning, Myocardial; Male; Malondialdehyde; Myocardial Infarction; Myocardium; Oxidative Stress; Piperidines; Rats; Rats, Sprague-Dawley; Remifentanil; Superoxide Dismutase; Superoxides; Tyrosine

Topics: Adamantane; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

Topics: Adamantane; Angina, Unstable; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Dipeptides; Dipeptidyl-Peptidase IV Inhibitors; Female; Humans; Hypoglycemic Agents; Male; Myocardial Infarction; Piperidines; Uracil

A contributory role for soluble epoxide hydrolase (sEH) in cardiac remodeling post-myocardial infarction (MI) has been suggested; however effects of sEH inhibition following MI have not been evaluated. In this study, we examined in vivo post-MI anti-remodeling effects of a novel sEH inhibitor (GSK2188931B) in the rat, and evaluated its direct in vitro effects on hypertrophy, fibrosis and inflammation.. Post-MI administered GSK2188931B (80 mg/kg/d in chow) for 5 weeks improved left ventricular (LV) ejection fraction compared to vehicle-treated (Veh) rats (P<0.01; Sham 65 ± 2%, MI+Veh 30 ± 2%, MI+GSK 43 ± 2%) without affecting systolic blood pressure. Percentage area of LV tissue sections stained positive for picrosirius red (PS) and collagen I (CI) were elevated in LV non-infarct zone (P<0.05; NIZ; PS: Sham 1.46 ± 0.13%, MI+Veh 2.14 ± 0.22%, MI+GSK 1.28 ± 0.14%; CI: Sham 2.57 ± 0.17%, MI+Veh 5.06 ± 0.58%, MI+GSK 2.97 ± 0.34%) and peri-infarct zone (P<0.001; PIZ; PS: Sham 1.46 ± 0.13%, MI+Veh 9.06 ± 0.48%, MI+GSK 6.31 ± 0.63%; CI: Sham 2.57±0.17%, MI+Veh 10.51 ± 0.64%, MI+GSK 7.77 ± 0.57%); GSK2188931B attenuated this increase (P<0.05). GSK2188931B reduced macrophage infiltration into the PIZ (P<0.05). GSK2188931B reduced AngII- and TNFα-stimulated myocyte hypertrophy, AngII- and TGFβ-stimulated cardiac fibroblast collagen synthesis, including markers of gene expression ANP, β-MHC, CTGF and CI (P<0.05). GSK2188931B reduced TNFα gene expression in lipopolysaccharide (LPS)-stimulated monocytes (P<0.05).. sEH inhibition exerts beneficial effects on cardiac function and ventricular remodeling post-MI, and direct effects on fibrosis and hypertrophy in cardiac cells. These findings suggest that sEH is an important contributor to the pathological remodeling following MI, and may be a useful target for therapeutic blockade in this setting.

Topics: Animals; Animals, Newborn; Epoxide Hydrolases; Male; Myocardial Infarction; Piperidines; Rats; Rats, Sprague-Dawley; Solubility; Triazines; Ventricular Remodeling

Nicotinamide phosphoribosyltransferase (Nampt) is a key enzyme for nicotinamide adenine dinucleotide (NAD(+)) biosynthesis, and recent evidence indicates its role in inflammatory processes. Here, we investigated the potential effects of pharmacological Nampt inhibition with FK866 in a mouse myocardial ischemia/reperfusion model. In vivo and ex vivo mouse myocardial ischemia/reperfusion procedures were performed.. Treatment with FK866 reduced myocardial infarct size, neutrophil infiltration, and reactive oxygen species (ROS) generation within infarcted hearts in vivo in a mouse model of ischemia and reperfusion. The benefit of FK866 was not shown in the Langendorff model (ex vivo model of working heart without circulating leukocytes), suggesting a direct involvement of these cells in cardiac injury. Sera from FK866-treated mice showed reduced circulating levels of the neutrophil chemoattractant CXCL2 and impaired capacity to prime migration of these cells in vitro. The release of CXCL8 (human homolog of murine chemokine CXCL2) by human peripheral blood mononuclear cells (PBMCs) and Jurkat cells was also reduced by FK866, as well as by sirtuin (SIRT) inhibitors and SIRT6 silencing, implying a pivotal role for this NAD(+)-dependent deacetylase in the production of this chemokine.. The pharmacological inhibition of Nampt might represent an effective approach to reduce neutrophilic inflammation- and oxidative stress-mediated tissue damage in early phases of reperfusion after a myocardial infarction.. Nampt inhibition appears as a new strategy to dampen CXCL2-induced neutrophil recruitment and thereby reduce neutrophil-mediated tissue injury in mice.

Topics: Acrylamides; Animals; Chemokine CXCL2; Humans; Male; Mice; Myocardial Infarction; Myocardial Reperfusion Injury; NAD; Neutrophil Infiltration; Nicotinamide Phosphoribosyltransferase; Oxidative Stress; Piperidines; Reactive Oxygen Species; Signal Transduction

To compare the cardiovascular safety of currently marketed dementia medications in new users in the United States and Denmark.. Retrospective cohort study.. Nationally representative sample of Medicare beneficiaries from 2006 through 2009 and nationwide Danish administrative registries from 1997 through 2007.. Individuals treated with a dementia medication aged 65 and older.. Hospitalizations for myocardial infarction (MI), heart failure, and syncope or atrioventricular block in both cohorts; fatal or nonfatal MI and cardiac death in the Danish cohort; and all-cause mortality in sensitivity analyses.. In 46,737 Medicare beneficiaries and 29,496 Danish participants, donepezil was the most frequently used medication. There were no substantial differences in the risk of MI or heart failure between participants using donepezil and those using other cholinesterase inhibitors (all hazard ratios (HR) crossing 1). In the Danish cohort, memantine was associated with fatal or nonfatal MI (HR = 1.33, 95% confidence interval (CI) = 1.08-1.63), cardiac death (HR = 1.31, 95% CI = 1.12-1.53), and a trend toward higher rates of hospitalization for MI (HR = 1.31, 95% CI = 0.98-1.76). Memantine was also associated with greater risk of all-cause mortality in the Medicare (HR = 1.20, 95% CI = 1.13-1.28) and Danish (HR = 1.83, 95% CI = 1.73-1.94) cohorts, suggesting that sicker individuals were selected for memantine therapy.. Cholinesterase inhibitors have similar cardiovascular risk profiles. Associations between memantine and fatal outcomes in Denmark may be related, in part, to selection of sicker individuals for memantine therapy.

Topics: Aged; Aged, 80 and over; Cholinesterase Inhibitors; Cohort Studies; Dementia; Denmark; Donepezil; Female; Heart Failure; Humans; Indans; Male; Medicare; Memantine; Myocardial Infarction; Nootropic Agents; Piperidines; Receptors, N-Methyl-D-Aspartate; United States

Previously, 7-[2-[4-(4-nitrobenzene)piperazinyl]ethyl]-1, 3-dimethylxanthine (KMUP-3) has been shown to induce aortic smooth muscle relaxation through K(ATP) channel opening and endothelial nitric oxide synthase (eNOS) enhancement. We further investigated whether KMUP-3 protects against myocardial remodelling after myocardial infarction (MI), and whether KMUP-3 increases the expression of eNOS in MI rats.. Wistar rats were randomly allocated into three groups: MI (n= 10), MI + KMUP-3 group (n= 10) and sham group (n= 10). MI was induced by ligation of the left anterior descending coronary artery. After recovery, the MI + KMUP-3 group received KMUP-3 (0.3 mg·kg(-1) ·day(-1) ) infusion for 4 weeks, while the MI and sham group received vehicle only. To further confirm that the effect of KMUP-3 is dependent on eNOS, KMUP-3 was applied in the culture of transforming growth factor-β-stimulated human cardiac fibroblasts.. KMUP-3 treatment attenuated cardiac hypertrophy post-MI and improved cardiac function. The fibrotic area was reduced by KMUP-3 both in central-, peri- and non-infarction areas. KMUP-3 enhanced the expression of eNOS and tissue inhibitor of metalloproteinase-1 (TIMP-1), but reduced matrix metalloproteinase-9 (MMP-9) expression. In vitro, the activities of KMUP-3 were blocked by pretreatment with the eNOS inhibitor N(ω) -nitro-L-arginine methyl ester.. The K(ATP) channel opener KMUP-3 preserved cardiac function after MI by enhancing the expression of eNOS. In addition, KMUP-3 restored the myocardial MMP-9/TIMP-1 balance and attenuated ventricular remodelling by an eNOS-dependent mechanism.

Topics: Animals; Blotting, Western; Cells, Cultured; Hemodynamics; Humans; Male; Matrix Metalloproteinase 9; Myocardial Infarction; Nitric Oxide Synthase Type III; Piperidines; Rats; Rats, Wistar; Tissue Inhibitor of Metalloproteinase-1; Ventricular Remodeling; Xanthines

The purpose of this study was to investigate the effects of various remifentanil strategies (preconditioning, postconditioning, or continuous infusion) against myocardial ischemia-reperfusion injury.. An in vitro experimental study using the Langendorff system.. A university research laboratory.. Male Sprague-Dawley rats (each n = 9).. Five different remifentanil strategies were performed in isolated rat hearts as follows: remifentanil preconditioning (R-Pre), remifentanil postconditioning (R-Post), ischemic targeting remifentanil (R1), reperfusion targeting remifentanil (R2), or both ischemic and reperfusion targeting remifentanil (R3). Infarct size and cardiodynamics were compared.. The infarct-risk volume ratio in groups R-Pre (13.7% ± 9.9%), R-Post (13.7% ± 12.3%), and R3 (12.6% ± 6.1%) were decreased significantly compared with the untreated control hearts (32.9% ± 11.1%, p < 0.01). There was no significant difference in the left ventricular-developed pressure (LVDP) recovery after reperfusion between the control (43.6% ± 14.5%) and R-Pre (34.8% ± 12.9%, p > 0.05) groups after reperfusion. However, the LVDP recovery in R-Post (21.6% ± 7.7%, p < 0.05), R1 (16.7% ± 19.8%, p < 0.01), R2 (22.2% ± 13.9%, p < 0.05), and R3 (16.2% ± 7.8%, p < 0.01) was decreased significantly compared with control hearts. There was no significant difference in the recovery of dP/dt(max) after reperfusion between the R-Pre (42.0% ± 16.9%) and control groups (39.0% ± 15.4%, p > 0.05), whereas the dP/dt(max) in R3 group (16.9% ± 9.0%) was decreased significantly compared with R-Pre (p < 0.05).. Preconditioning or postconditioning by remifentanil and the continuous infusion of remifentanil effectively reduce myocardial infarction, whereas reperfusion targeting ischemic targeting or reperfusion targeting remifentanil does not. Remifentanil preconditioning better preserves myocardial function, especially LVDP, than other remifentanil strategies.

Topics: Anesthetics, Intravenous; Animals; Body Weight; Cardiotonic Agents; Coloring Agents; Coronary Circulation; Heart; Heart Function Tests; In Vitro Techniques; Ischemic Postconditioning; Ischemic Preconditioning, Myocardial; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Organ Size; Piperidines; Rats; Rats, Sprague-Dawley; Remifentanil; Reperfusion; Tetrazolium Salts; Ventricular Function, Left

We have previously demonstrated that the chronic intervention in the cholinergic system by donepezil, an acetylcholinesterase inhibitor, plays a beneficial role in suppressing long-term cardiac remodeling after myocardial infarction (MI). In comparison with such a chronic effect, however, the acute effect of donepezil during an acute phase of MI remains unclear. Noticing recent findings of a cholinergic mechanism for anti-inflammatory actions, we tested the hypothesis that donepezil attenuates an acute inflammatory tissue injury following MI.. In isolated and activated macrophages, donepezil significantly reduced intra- and extracellular matrix metalloproteinase-9 (MMP-9). In mice with MI, despite the comparable values of heart rate and blood pressure, the donepezil-treated group showed a significantly lower incidence of cardiac rupture than the untreated group during the acute phase of MI. Immunohistochemistry revealed that MMP-9 was localized at the infarct area where a large number of inflammatory cells including macrophages infiltrated, and the expression and the enzymatic activity of MMP-9 at the left ventricular infarct area was significantly reduced in the donepezil-treated group.. The present study suggests that donepezil inhibits the MMP-9-related acute inflammatory tissue injury in the infarcted myocardium, thereby reduces the risk of left ventricular free wall rupture during the acute phase of MI.

Topics: Alzheimer Disease; Animals; Blood Pressure; Cells, Cultured; Cholinesterase Inhibitors; Donepezil; Electrophoresis, Polyacrylamide Gel; Heart; Heart Rate; Heart Rupture, Post-Infarction; Humans; Immunohistochemistry; Indans; Macrophages; Male; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Myocardial Infarction; Myocardium; Piperidines; Reverse Transcriptase Polymerase Chain Reaction

Remifentanil is a commonly used opioid in anesthesia with cardioprotective effect in ischemia-reperfused (I/R) heart. We evaluated the influence of remifentanil on myocardial infarct size and expressions of proteins involved in apoptosis in I/R rat heart following various time protocols of remifentanil administration. Artificially ventilated anesthetized Sprague-Dawley rats were subjected to a 30 min of left anterior descending coronary artery occlusion followed by 2 h of reperfusion. Rats were randomly assigned to one of five groups; Sham, I/R only, remifentanil preconditioning, postconditioning and continuous infusion group. Myocardial infarct size, the phosphorylation of ERK1/2, Bcl2, Bax and cytochrome c and the expression of genes influencing Ca2+ homeostasis were assessed. In remifentanil-administered rat hearts, regardless of the timing and duration of administration, infarct size was consistently reduced compared to I/R only rats. Remifentanil improved expression of ERK1/2 and anti-apoptotic protein Bcl2, and expression of sarcoplasmic reticulum genes which were significantly reduced in the I/R rats only. Remifentanil reduced expression of pro-apoptotic protein, Bax and cytochrome c. These suggested that remifentanil produced cardioprotective effect by preserving the expression of proteins involved in anti-apoptotic pathways, and the expression of sarcoplasmic reticulum genes in I/R rat heart, regardless of the timing of administration.

Topics: Adjuvants, Anesthesia; Animals; Apoptosis; bcl-2-Associated X Protein; Blotting, Western; Calcium; Cell Survival; Cytochromes c; Disease Models, Animal; Gene Expression Regulation; Hemodynamics; Homeostasis; Male; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Phosphorylation; Piperidines; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Remifentanil; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sarcoplasmic Reticulum; Time Factors

Ischemic pre- or post-conditioning of the heart has been shown to involve opioid receptors. Remifentanil, an ultra-short-acting selective mu opioid receptor agonist in clinical use, pre-conditions the rat heart against ischemia-reperfusion injury. This study investigates whether remifentanil post-conditioning is also cardioprotective.. Remifentanil post-conditioning (5-min infusion at 1, 5, 10 or 20 microg/kg/min) or ischemic post-conditioning (three cycles of a 10 s reperfusion interspersed with a 10 s ischemia) was induced in an open-chest rat heart model of ischemia and reperfusion injury, in the presence or absence of nor-binaltorphimine, naltrindole or CTOP, specific kappa, delta and mu opioid receptor antagonists, respectively. The same sequence of experiments was repeated in the isolated heart model using the maximal protective dose of remifentanil from the dose-response studies.. Both ischemic and remifentanil post-conditioning reduced the myocardial infarct size relative to the control group in both models. This cardioprotective effect for both post-conditioning regimes was prevented by the prior administration of nor-binaltorphimine and naltrindole but not CTOP. The sole administration of the antagonists had no effect on the size of myocardial infarction.. These results indicate that remifentanil post-conditioning protects the heart from ischemia-reperfusion injury to a similar extent as of ischemic post-conditioning. This protection involves kappa and delta but not mu opioid receptor activation. This drug has great potential as a clinical post-conditioning modality as it can be given in large doses without prolonged opioid-related side effects.

Topics: Analgesics, Opioid; Animals; Blood Pressure; Cardiotonic Agents; Dose-Response Relationship, Drug; Heart Rate; In Vitro Techniques; Ischemic Preconditioning, Myocardial; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Naltrexone; Narcotic Antagonists; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, Opioid, delta; Receptors, Opioid, kappa; Receptors, Opioid, mu; Remifentanil; Somatostatin

Diabetes mellitus has been known to mitigate ischemic or pharmacologic preconditioning in ischemia-reperfusion injuries. Remifentanil is a widely used opioid in cardiac anesthesia that possesses a cardioprotective effect against ischemia-reperfusion. We evaluated whether diabetes affected remifentanil preconditioning induced cardioprotection in ischemia-reperfusion rat hearts in view of anti-apoptotic pathways of survival and Ca(2+) homeostasis. Streptozotocin-induced, diabetic rats and age-matched wild-type Sprague-Dawley rats were subjected to a left anterior descending coronary artery occlusion for 30min followed by 1h of reperfusion. Each diabetic and wild-type rat was randomly assigned to the sham, ischemia-reperfusion only, or remifentanil preconditioning group. Myocardial infarct size, activities of ERK1/2, Bcl2, Bax and cytochrome c, and gene expression influencing Ca(2+) homeostasis were assessed. Remifentanil preconditioning significantly reduced myocardial infarct size compared to ischemia-reperfusion only in wild-type rats but not in diabetic rats. Remifentanil preconditioning increased expression of ERK1/2 and anti-apoptotic protein Bcl-2 and decreased expression of pro-apoptotic proteins, Bax and cytochrome c, compared to ischemia-reperfusion only in wild-type rats. In diabetic rat hearts, however, remifentanil preconditioning failed to recover the phosphorylation state of ERK1/2 and to repress apoptotic signaling. In addition, diabetes minimized remifentanil induced modulation of abnormal changes in sarcoplasmic reticulum genes and proteins in ischemia-reperfusion rat hearts. In conclusion, diabetes mitigated remifentanil induced cardioprotection against ischemia-reperfusion, which might be associated with reduced recovery of the activities of proteins involved in anti-apoptotic pathways including ERK1/2 and the abnormal expression of sarcoplasmic reticulum genes as a result of ischemia-reperfusion in rat hearts.

Topics: Animals; Apoptosis; Cardiotonic Agents; Cell Survival; Diabetes Mellitus; Gene Expression Regulation; Heart; Hemodynamics; Ischemic Preconditioning, Myocardial; Male; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Myocardial Infarction; Myocardium; Phosphorylation; Piperidines; Rats; Rats, Sprague-Dawley; Remifentanil; Reperfusion Injury; Sarcoplasmic Reticulum

In an earlier study we demonstrated the beneficial effect of direct vagal electrical stimulation on cardiac remodeling and survival. In the study reported here, we attempted to reproduce the effect of vagal enhancement through the administration of an acetylcholinesterase inhibitor, donepezil. A rat model of heart failure following extensive healed myocardial infarction was used. Compared to their nontreated counterparts, rats given donepezil (5 mg/kg/day) in their drinking water had a smaller biventricular weight (3.40 +/- 0.13 vs. 3.02 +/- 0.21 g/kg body weight, P < 0.05), and maximal rate of rise (3256 +/- 955 vs. 3822 +/- 389 mmHg/s, P < 0.05) and the end-diastolic value (30.1 +/- 5.6 vs. 23.2 +/- 5.7 mmHg, P < 0.05) of left ventricular pressure were improved. Neurohumoral factors were suppressed in donepezil-treated rats (norepinephrine 1885 +/- 1423 vs. 316 +/- 248 pg/ml, P < 0.01; brain natriuretic peptide 457 +/- 68 vs. 362 +/- 80 ng/ml, P < 0.05), and the high-frequency component of heart rate variability showed a nocturnal increase. These findings indicated that donepezil reproduced the anti-remodeling effect of electrical vagal stimulation. Further studies are warranted to evaluate the clinical usefulness of donepezil in heart failure.

Topics: Animals; Cholinesterase Inhibitors; Donepezil; Heart; Heart Failure; Heart Rate; Indans; Male; Myocardial Infarction; Piperidines; Rats; Rats, Sprague-Dawley; Vagus Nerve

CB1 antagonism is associated with reduced doxorubicin-induced cardiotoxicity and decreased cerebrocortical infarction. Rimonabant, a selective CB1 receptor antagonist, was, before it was withdrawn, proposed as a treatment for obesity and reported to reduce cardiovascular risk by improving glucose and lipid profiles and raising adiponectin levels. The cardioprotective actions of rimonabant in 6-week-old C57BL/6J mice fed either high-fat (HFD) or standard diets (STD) for 8 weeks were investigated. At 14 weeks, mice received rimonabant (10 mg/kg/day, i.p.) or vehicle for 1 week and were then subjected to an in vivo acute myocardial infarction. The influence of rimonabant on infarct size (IS) in CB1 knockout (CB1-/-) and wild-type (CB1+/+) mice was also examined. C57BL/6J mice that had been maintained on STD or HFD exhibited 4.3 and 21.4% reductions in body weight following 7 days rimonabant treatment. Rimonabant reduced IS in both STD (29.6 +/- 3.5% vs. 49.8 +/- 6.9% in control, P < 0.05) and HFD (26.9 +/- 1.5% vs. 48.7 +/- 7% in control, P < 0.05) mice. In CB1-/- mice rimonabant failed to reduce body weight or IS (51.0 +/- 5.3% vs. 49.7 +/- 4.7% in control, P > 0.05), although significant reductions were seen in CB1+/+ mice (IS, 48.9 +/- 4.6% control vs. 30.5 +/- 3.1% rimonabant, P < 0.05). To exclude the possibility that weight loss alone induced cardioprotection, HFD mice were switched to STD for 7 days (HFD-STD), resulting in an 11.3 +/- 1.0% decrease in body weight compared to control (+2.1 +/- 1.1% in HFD). This, however, was not associated with IS reduction (39.1 +/- 3.9% HFD-STD vs. 40.0 +/- 5.3% HFD, P > 0.05). Serum and cardiac adiponectin levels were unaltered by rimonabant treatment. HL-1 cell death was not prevented by 1 or 7 days treatment with rimonabant. We conclude that rimonabant-induced infarct limitation may involve the CB1 receptor, although not necessarily cardiac CB1 receptors, and is unrelated to weight loss or altered adiponectin synthesis.

Topics: Adiponectin; Animals; Blotting, Western; Diet, Atherogenic; Dietary Fats; Enzyme-Linked Immunosorbent Assay; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardial Infarction; Myocardial Reperfusion Injury; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant

Increased activation of poly(ADP-ribose) polymerase (PARP) enzyme has been implicated in the pathogenesis of acute and chronic myocardial dysfunction. We have demonstrated the protective effect of PARP inhibitors against postinfarction myocardial remodeling and heart failure. The primary aim of our recent work was to compare the effect and efficacy of a potent PARP-inhibitor (L-2286) to enalapril, a widely used angiotensin-converting enzyme (ACE) inhibitor. in experimental heart failure model. Both L-2286 and enalapril were tested in a rat model of chronic heart failure after isoproterenol-induced myocardial infarction. After a 12-week treatment period, echocardiography was performed, cardiac hypertrophy and interstitial collagen deposition were assessed, and the phosphorylation state of Akt-1/GSK-3beta pathway as well as the PKC and MAPK kinases were determined. Both PARP and ACE inhibition reduced the progression of postinfarction heart failure by attenuating cardiac hypertrophy and interstitial fibrosis. More importantly, PARP inhibition increased the activity of the prosurvival signal transduction factors (Akt-1/GSK-3beta pathway, PKCepsilon). Due to these effects, L-2286 improved the systolic left ventricular function. Enalapril treatment exerted a similar, but weaker protective effect against postinfarction myocardial remodeling and heart failure. In conclusion, we demonstrated in an experimental heart failure model that L-2286 decreased the postinfarction myocardial remodeling more effectively than enalapril treatment.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Cardiomegaly; Disease Models, Animal; Echocardiography; Enalapril; Enzyme Inhibitors; Fibrosis; Heart Failure; Male; Myocardial Infarction; Piperidines; Poly(ADP-ribose) Polymerase Inhibitors; Quinazolines; Rats; Rats, Sprague-Dawley; Signal Transduction; Ventricular Remodeling

Diabetes mellitus (DM) is a worldwide epidemic. Its prevalence is rapidly increasing in both developing and developed countries. Coronary heart disease (CHD) is highly prevalent and is the major cause of morbidity and mortality in patients with diabetes. Individuals with prediabetes states, with or without known CHD, should undergo lifestyle modifications aimed at preventing DM. In patients with CHD and DM, routine use of aspirin and an angiotensin-converting enzyme inhibitor, along with strict glycemic, blood pressure, and lipid control, is strongly recommended. Intense insulin therapy may be needed for glycemic control, and high-dose statin therapy may be needed for lipid control. For blood pressure control, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are considered first-line therapy. Noncompliance with medications and/or lifestyle measures and underprescription of evidence-based therapies remain important unsolved problems.

Topics: Antihypertensive Agents; Cholesterol, HDL; Cholesterol, LDL; Coronary Artery Disease; Diabetes Mellitus; Diabetic Angiopathies; Humans; Hyperglycemia; Hypoglycemic Agents; Hypolipidemic Agents; Insulin Resistance; Life Style; Myocardial Infarction; Obesity; Pioglitazone; Piperidines; Platelet Aggregation Inhibitors; Prediabetic State; Pyrazoles; Ramipril; Rimonabant; Risk Assessment; Thiazolidinediones; Triglycerides; Weight Loss

Preconditioning with remifentanil (RPC) provides immediate cardioprotection in rats via all three types of opioid (OP) receptor. This study sought to investigate whether remifentanil also confers delayed cardioprotection via OP receptors.. Male rats received preconditioning either by ischaemia (IPC; 5 min occlusion, 5 min reperfusion x 3) or with remifentanil (RPC; 1, 5, 10, and 20 microg kg(-1) min(-1), 20 min infusion). After 24 h, all animals were subjected to 30 min occlusion of the left coronary artery and 2 h of reperfusion. Subsequently, the time-course effect of RPC (10 microg kg(-1) min(-1), 20 min infusion) was determined at 12, 16, 24, 32, 36, and 48 h intervals, using the same experimental procedure. The effect of RPC (10 microg kg(-1) min(-1), 20 min infusion) and IPC in the presence of selective OP receptor antagonists was evaluated at the 24 h interval. Infarct size (IS), as a percentage of the area at risk (AAR), was determined.. Pre-treatment with remifentanil at 1, 5, 10, and 20 microg kg(-1) min(-1) significantly reduced the IS/AAR at 24 h with the maximum effect at 10 microg kg(-1) min(-1). Remifentanil at 10 microg kg(-1) min(-1) significantly reduced the IS at 12 h [32.5 (sd 9.1)%]; 16 h [26.1 (2.8)%]; 24 h [19.5 (5.0)%]; 32 h [31.2 (9.1)%]; and 36 h [36.4 (9.4)%] after drug administration. The maximal reduction in IS was seen at 24 h and the effect completely disappeared at 48 h [36.4 (9.4)%]. The protective effect of RPC was abolished or significantly attenuated by blockade of any of the three OP receptors with selective antagonists.. Like IPC, remifentanil produces delayed cardioprotection in anaesthetized rats 12-36 h after administration. The protective effect is mediated via all three OP receptors.

Topics: Analgesics, Opioid; Animals; Blood Pressure; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Evaluation, Preclinical; Heart Rate; Ischemic Preconditioning, Myocardial; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Narcotic Antagonists; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, Opioid; Remifentanil; Time Factors; Treatment Outcome

The inhibition of glycogen synthase kinase-3beta (GSK-3beta) via phosphorylation by Akt or protein kinase C (PKC), or the activation of mitogen-activated protein kinase (MAPK) cascades can play a pivotal role in left ventricular remodeling following myocardial infarction. Our previous data showed that MAPK and phosphatidylinositol-3-kinase/Akt pathways could be modulated by poly(ADP-ribose)polymerase (PARP) inhibition raising the possibility that cardiac hypertrophic signaling responses may be favorably influenced by PARP inhibitors. A novel PARP inhibitor (L-2286) was tested in a rat model of chronic heart failure following isoproterenol-induced myocardial infarction. Subsequently, cardiac hypertrophy and interstitial collagen deposition were assessed; additionally, mitochondrial enzyme activity and the phosphorylation state of GSK-3beta, Akt, PKC and MAPK cascades were monitored. PARP inhibitor (L-2286) treatment significantly reduced the progression of postinfarction heart failure attenuating cardiac hypertrophy and interstitial fibrosis, and preserving the integrity of respiratory complexes. More importantly, L-2286 repressed the hypertrophy-associated increased phosphorylation of panPKC, PKC alpha/betaII, PKC delta and PKC epsilon, which could be responsible for the activation of the antihypertrophic GSK-3beta. This work provides the first evidence that PARP inhibition beneficially modulates the PKC/GSK-3beta intracellular signaling pathway in a rat model of chronic heart failure identifying a novel drug target to treat heart failure.

Topics: Animals; Cardiomegaly; Collagen Type III; Electrocardiography; Enzyme Inhibitors; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Heart Failure; Isoproterenol; Male; Mitogen-Activated Protein Kinases; Myocardial Infarction; Natriuretic Peptide, Brain; Phosphorylation; Piperidines; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Protein Kinase C; Quinazolines; Rats; Rats, Sprague-Dawley; Signal Transduction; Ventricular Remodeling

Endocannabinoids have been implicated in protective effects in the heart and brain, but the mechanism of possible infarct-size-reducing effects remains controversial. Using a model of delayed preconditioning (PC), rats received the nitric oxide (NO) donor nitroglycerin (0.15 mg/h/kg) for 24 hours via transdermal application. Two days later, rat isolated perfused hearts were subjected to global, no-flow ischemia (20 min), and reperfusion (120 min). Cannabinoid receptor antagonists were given before no-flow throughout the protocol. Endocannabinoids were detected by liquid chromatography and mass spectrometry. NO-induced PC reduced the left ventricular infarct size from 40.9 +/- 3.9% to 27.5 +/- 3.8% (P < 0.05). Treatment with the specific CB1 cannabinoid receptor antagonist AM-251 (0.3 microM) prevented the protective effect of PC on infarct size (40.2 +/- 4.7%, P > 0.05 vs. controls). On the contrary, the specific CB2 receptor antagonist AM-630 (0.3 microM) did not alter infarct size (31.6 +/- 6.3%, P > 0.05 vs. PC alone). Recovery of left ventricular developed pressure and coronary flow was incomplete in control and NO-pretreated hearts and not consistently altered by cannabinoid receptor antagonists. PC increased the heart tissue content of the endocannabinoid 2-arachidonylglycerol (2-AG) from 4.6 +/- 1.0 nmol/g in controls to 12.0 +/- 2.1 nmol/g (P < 0.05). Tissue levels of the endocannabinoid arachidonylethanolamide (anandamide) remained unchanged (19.8 +/- 3.9 pmol/g vs. 19.5 +/- 4.8 pmol/g). 2-AG (1 microM) or its metabolically stable derivative noladinether (0.1 microM), given 30 minutes before ischemia/reperfusion in unpreconditioned hearts, mimicked the cardioprotective effects of PC and reduced infarct size. We conclude that delayed PC through transdermal nitroglycerin application increases the production of the endocannabinoid 2-AG which elicits protective effects against myocardial infarction via CB1 cannabinoid receptors which represents one new mechanism of NO-mediated PC.

Topics: Animals; Arachidonic Acids; Blood Pressure; Cannabinoid Receptor Modulators; Coronary Vessels; Endocannabinoids; Glycerides; Heart; Heart Rate; Indoles; Ischemic Preconditioning, Myocardial; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Nitric Oxide; Nitric Oxide Donors; Nitroglycerin; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Rats; Rats, Wistar; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Regional Blood Flow

To examine whether the protective effect of remifentanil preconditioning (RPC) on postischemic hearts is mediated by protein kinase (PKC) activation in comparison with ischemic preconditioning (IPC).. Male Sprague-Dawley rats were anesthetized and their chests were opened. The experiment was performed with chelerythrine (CHE, 2 mg/kg), GF109203X (0.05 mg/kg) protein kinase C (PKC) inhibitors administered before RPC (remifentanil 6 microg x kg(-1) x min(-1) x 3 cycle) or IPC, respectively. Infarct size (IS), as a percentage of the area at risk (AAR), was determined by triphenyltetrazolium staining.. In groups subjected to IPC and RPC the IS/AAR were significantly reduced (IS/AAR from 52.7%+/-5.5% to 12.9%+/-3.4%, P<0.01 vs CON and 16.2%+/-6.4%, P<0.01 vs CON), respectively. CHE and GF, both PKC inhibitors, administered 5 min before RPC or IPC completely abolished the cardioprotective effect of RPC (IS/AAR: CHE+RPC 51.2%+/-5.0%, GF+RPC 53.6%+/-6.1%, P>0.05 vs CON) or IPC (CHE+IPC 53.7%+/-4.3%, GF+IPC 54.1%+/-6.2%, P>0.05 vs CON). The difference was not significant in any of the hemodynamic parameters between control and treatment groups during ischemia and reperfusion.. Remifentanil confers myocardial protection against ischemic injury through a mechanism that is similar to IPC and involves PKC activation.

Topics: Alkaloids; Animals; Benzophenanthridines; Cardiotonic Agents; Hemodynamics; Indoles; Ischemic Preconditioning, Myocardial; Male; Maleimides; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Phenanthridines; Piperidines; Protein Kinase C; Rats; Rats, Sprague-Dawley; Remifentanil

We tested the hypothesis that simultaneous inhibition of the endothelial integrin alpha(v)beta(3) and the platelet glycoprotein IIb/IIIa receptor will substantially reduce infarct size in a model of acute coronary thrombosis and primary angioplasty.. Dogs were subjected to thrombus formation in the left anterior descending coronary artery followed by primary angioplasty. Prior to angioplasty, they were randomized into 3 treatment groups. Group 1 (n=7) received saline; Group 2 (n=9) received MK-383 that inhibits only IIb/IIIa; and Group 3 (n=9) received CP-4715, that inhibits both IIb/IIIa and alpha(v)beta(3).. There was a 59% reduction in infarct size in dogs receiving CP-4715 compared to controls (p=0.002) and a 37% reduction compared to the dogs receiving MK-383 (p=0.04). Myocardium microthrombi were seen to be reduced similarly with both drugs on post-mortem (99m)Tc-DMP444 autoradiography that reflects in vivo IIb/IIIa receptor activity. In vivo imaging using echistatin-conjugated and leukocyte-targeted microbubbles revealed significant alpha(v)beta(3) inhibition and reduction in active leukocyte recruitment only in Group 3 dogs. Myocardial blood flow and regional function after reperfusion were also significantly better in this group.. Simultaneous inhibition of IIb/IIIa and alpha(v)beta(3) causes a marked reduction in infarct size in a model of acute coronary thrombosis and primary PTCA that is associated with reduced myocardial microthrombi and inflammation, as well as improved myocardial blood flow and regional function. These results may have important implications in the treatment of acute coronary syndromes.

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Animals; Coronary Thrombosis; Dogs; Integrin alphaVbeta3; Male; Models, Animal; Myocardial Infarction; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pyrimidines; Random Allocation; Tirofiban; Tyrosine

Topics: Aged; Anesthesia, General; Anesthetics, Intravenous; Atracurium; Cardiac Surgical Procedures; Cardiopulmonary Bypass; Humans; Intubation, Intratracheal; Male; Monitoring, Intraoperative; Myocardial Infarction; Narcolepsy; Neuromuscular Blocking Agents; Piperidines; Propofol; Remifentanil

To explore the effects of M3 receptor on myocyte apoptosis induced by acute myocardial infarction in rats.. Rat model was induced by ligation of the anterior branch of the left coronary artery. All animals were divided into four groups: sham-operated group, occlusion group, choline group (10 mg x kg(-1), iv), and 4DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) group (0.12 mg x kg(-1), iv). The serum malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were determined. The infarct size areas on the myocardium were identified by TTC staining. The apoptosis in cardiomyocyte was detected by TUNEL assay and apoptosis-related proteins in Bcl-2 and Fas expression were measured by immunohistochemistry assay.. M3 receptor agonist choline reduced serum MDA content and increased SOD activity. The myocardial expression of Bcl-2 was increased, whereas the expression of Fas was decreased by choline. However, blockade of M3 receptor by 4DAMP completely inhibited these effects of choline on cardiac myocytes.. Activation of M3 receptor has protective effect on myocyte apoptosis induced by acute myocardial infarction in rat, and this effect might be related to modulating the expression of some immediateearly genes including Bcl-2 and Fas.

Topics: Animals; Apoptosis; Choline; fas Receptor; Male; Malondialdehyde; Myocardial Infarction; Myocardium; Myocytes, Cardiac; Piperidines; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Wistar; Receptor, Muscarinic M3; Receptors, Tumor Necrosis Factor; Superoxide Dismutase

We investigated the influence of the narcotic anesthetic remifentanil on irreversible myocardial ischemic injury.. New Zealand White rabbits were anesthetized with propofol (0.7-1.8 mg.kg.min) and then subjected to 30 min regional myocardial ischemia and 3 h reperfusion (CON). Some animals also underwent ischemic preconditioning, elicited by either one (IP1) or two (IP2) cycles of 5 min ischemia and 5 min reperfusion, and/or remifentanil, administered either as a transient infusion mimicking the preconditioning protocol (RP2, 10 microg x kg x min) or as a continuous infusion (R, 3-10 microg x kg x min). Rabbits were randomly assigned to experimental groups. Infarct size was assessed with tetrazolium. Results are reported as mean+/-SD.. Non-preconditioned infarct size was approximately 50% of the area-at-risk (49.6+/-20.1% CON). Both one and two cycles of ischemic preconditioning markedly reduced infarct size (49.6+/-20.1% CON versus 18.6+/-8.6% IP and versus 7.5+/-7.6% IP2; both p<0.001). Preconditioning with remifentanil modestly reduced infarct size (49.6+/-20.1% CON versus 29.3+/-8.5% RP2; p<0.01). However, sustained administration of remifentanil did not provide protection (49.6+/-20.1% CON versus 43.9+/-16.2% R), and it attenuated the protection offered by preconditioning (49.6+/-20.1% CON versus 35.6+/-20.7% R+IP1, p=NS; and versus 14.5+/-14.5% R+IP2; p<0.05).. Transient pre-ischemic administration of remifentanil modestly reduces infarct size in propofol-anesthetized rabbits, but continuous administration of remifentanil increases the threshold for ischemic preconditioning-induced infarct limitation.

Topics: Anesthetics; Animals; Ischemic Preconditioning, Myocardial; Myocardial Infarction; Piperidines; Rabbits; Remifentanil

Recent trials reveal no benefit and possible harm from chronic hormone replacement therapy (HRT). Less is known about intermediate-term outcomes associated with HRT use in the setting of acute coronary syndromes (ACS).. To examine the prevalence of HRT use and relationships with intermediate-term outcomes among women with ACS, we classified as HRT users or nonusers 4029 postmenopausal women (age > 50 years or postmenopausal by case report form) randomized in the Sibrafiban versus Aspirin to Yield Maximum Protection from Ischemic Heart Events Post-Acute Coronary Syndromes (SYMPHONY) and 2nd SYMPHONY trials. Outcomes included 90-day and 1-year death and 90-day stroke, death, or myocardial infarction (MI); death, MI, or stroke; and death, MI, or severe recurrent ischemia (SRI).. HRT use was 13% overall and varied by region (Asia, 0%; Eastern Europe, 0.2%; Latin America, 0.8%; Western Europe, 4%; Australia/New Zealand, 12%; Canada, 14%; United States, 24%); estrogen-only regimens were most common (90%). HRT users were younger, had higher estimated creatinine clearance, more frequently were smokers and had prior revascularization, but less frequently had diabetes, prior angina, or heart failure. Unadjusted 90-day and 1-year mortality rates were lower among HRT users (hazard ratios [95% CI] 0.48 [0.23-0.98] and 0.35 [0.18-0.68], respectively) but after multivariable adjustment, were not significantly different. Ninety-day stroke and composite end points did not differ between HRT users and nonusers.. HRT use (predominantly estrogen-only) was low among patients with ACS but varied by region and was not associated with improved intermediate-term outcomes. These results are consistent with the absence of benefit from HRT use (combination or estrogen only) in previous studies in more stable populations.

Topics: Aged; Aspirin; Attitude to Health; Coronary Disease; Estrogen Replacement Therapy; Female; Global Health; Humans; Middle Aged; Myocardial Infarction; Odds Ratio; Oximes; Piperidines; Platelet Aggregation Inhibitors; Postmenopause; Prevalence; Randomized Controlled Trials as Topic; Surveys and Questionnaires; Survival Analysis; Time Factors; Treatment Outcome; Women's Health

1 The purpose of this study was to determine whether endocannabinoids can protect the heart against ischaemia and reperfusion. 2 Rat isolated hearts were exposed to low-flow ischaemia (0.5-0.6 ml min(-1)) and reperfusion. Functional recovery as well as CK and LDH overflow into the coronary effluent were monitored. Infarct size was determined at the end of the experiments. Phosphorylation levels of p38, ERK1/2, and JNK/SAPK kinases were measured by Western blots. 3 None of the untreated hearts recovered from ischaemia during the reperfusion period. Perfusion with either 300 nM palmitoylethanolamide (PEA) or 300 nM 2-arachidonoylglycerol (2-AG), but not anandamide (up to 1 micro M), 15 min before and throughout the ischaemic period, improved myocardial recovery and decreased the levels of coronary CK and LDH. PEA and 2-AG also reduced infarct size. 4 The CB(2)-receptor antagonist, SR144528, blocked completely the cardioprotective effect of both PEA and 2-AG, whereas the CB(1)-receptor antagonist, SR141716A, blocked partially the effect of 2-AG only. In contrast, both ACEA and JWH015, two selective agonists for CB(1)- and CB(2)- receptors, respectively, reduced infarct size at a concentration of 50 nM. 5 PEA enhanced the phosphorylation level of p38 MAP kinase during ischaemia. PEA perfusion doubled the baseline phosphorylation level of ERK1/2, and enhanced its increase upon reperfusion. The cardioprotective effect of PEA was completely blocked by the p38 MAP kinase inhibitor, SB203580, and significantly reduced by the ERK1/2 inhibitor, PD98059, and the PKC inhibitor, chelerythrine. 6 In conclusion, endocannabinoids exert a strong cardioprotective effect in a rat model of ischaemia-reperfusion that is mediated mainly through CB(2)-receptors, and involves p38, ERK1/2, as well as PKC activation.

Topics: Amides; Animals; Arachidonic Acids; Biomarkers; Blotting, Western; Camphanes; Cannabinoid Receptor Modulators; Endocannabinoids; Ethanolamines; Glycerides; Heart; Imidazoles; L-Lactate Dehydrogenase; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion Injury; p38 Mitogen-Activated Protein Kinases; Palmitic Acids; Piperidines; Protein Kinase C; Pyrazoles; Pyridines; Rats; Rats, Sprague-Dawley; Rimonabant; Signal Transduction

We have found that intravenous administration of cannabinoid receptor (CB) agonist HU-210 (0.05 mg/kg), increases cardiac resistance against arrhythmogenic effect of epinephrine, aconitine, coronary artery occlusion and reperfusion in rats. Pretreatment with CB2-receptor antagonist, SR144528 (1 mg/kg), completely abolished the antiarrhythmic effect of HU-210. However this effect of HU-210 was not attenuated by pretreatment with CB1-receptor antagonist, SR141716A (3 mg/kg). We also found that HU-210 (0.05 mg/kg) decreased the relationship between infarction size and area of ischemia. It is concluded that CB2 receptor stimulation promotes an increase in the cardiac resistance against arrhythmogenic influences and probably increases myocardial tolerance of both ischemic and reperfusion damages in rats.

Topics: Aconitine; Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Arterial Occlusive Diseases; Camphanes; Cannabinoids; Coronary Artery Disease; Dronabinol; Epinephrine; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Piperidines; Pyrazoles; Rats; Rats, Wistar; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; Receptors, Drug; Rimonabant

We have investigated the involvement of the endocannabinoid system in the delayed cardioprotection conferred by heat stress preconditioning in the isolated rat heart.. Rats were divided into eight groups (n=7 in each group), subjected to either heat stress (42 degrees C for 15 min, HS groups) or sham anaesthesia (Sham groups). Twenty-four hours later, their hearts were isolated, retrogradely perfused, and subjected to a 30-min occlusion of the left coronary artery followed by 120 min of reperfusion. Some hearts were perfused with either SR 141716 (a cannabinoid CB(1) receptor antagonist, 1 microM), SR 144528 (a CB(2) receptor antagonist, 1 microM) or L-NAME (a NOS inhibitor, 3 microM) 5 min before ischaemia and during the ischaemic period.. The infarct size-reducing effect conferred by heat stress (35.7+/-1.8% in Sham to 14.1+/-0.6% in HS groups) was not altered by the perfusion of SR 141716 (11.2+/-1.5%) but was abolished by both SR 144528 (36.6+/-1.6%) and L-NAME (32.0+/-4.4%). In hearts from non-heat-stressed rats, perfusion with SR 141716 (32.8+/-1.6%), SR 144528 (33.4+/-2.2%) and L-NAME (31.6+/-2.9%) had no effect on infarct size.. These results suggest an involvement of endocannabinoids, acting through CB(2) receptors, and NO in the cardioprotection conferred by heat stress against myocardial ischaemia. The possible interaction between both mediators of the heat stress response remains to be determined.

Topics: Analysis of Variance; Animals; Camphanes; Cannabinoid Receptor Modulators; Cannabinoids; Endocannabinoids; Fever; Ischemic Preconditioning, Myocardial; Male; Myocardial Infarction; Myocardium; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Perfusion; Piperidines; Pyrazoles; Rats; Rats, Wistar; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; Receptors, Drug; Rimonabant; Time Factors

The secondary prevention benefit of therapy with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) has been clearly demonstrated; however, the role of early initiation of statins after acute coronary syndromes (ACSs) is unknown.. To evaluate the association of early statin initiation (< or = 7 days) after ACS with 90-day and 1-year outcomes.. Observational cohort from databases of 2 randomized clinical trials, SYMPHONY and 2nd SYMPHONY.. Nine hundred thirty-one clinical centers in 37 countries.. A total of 12,365 ACS patients randomized from August 1997 to August 1999 who were not taking statins prior to the index ACS and who either started statin therapy early (median, 2.0 [interquartile range, 1.0-3.1] days after ACS; n = 3952) or survived more than 5 days after ACS and never received statin therapy (n = 8413).. Ninety-day incidence of death; death or myocardial infarction (MI); and death, MI, or severe recurrent ischemia; as well as 1-year incidence of death.. Ninety-day and 1-year unadjusted mortality comparison suggested early statin benefit (1.2% for early statins vs 2.1% for no statins; hazard ratio [HR], 0.58; 95% confidence interval [CI], 0.42-0.81 for 90-day comparisons and 2.3% for early statins vs 4.4% for no statins; HR, 0.52; 95% CI, 0.40-0.68 for 1-year comparison). However, no benefit was evident for 90-day death or MI (6.5% vs 6.9%; HR, 0.95; 95% CI, 0.82-1.11) or death, MI, or severe recurrent ischemia (9.2% vs 8.9%; HR, 1.04; 95% CI, 0.92-1.18). After propensity and covariate adjustment, there were no 90-day or 1-year differences between the early-statin group and the no-statin group. The 90-day adjusted HR for death was 1.08 (95% CI, 0.75-1.56); for death or MI, 1.08 (95% CI, 0.91-1.29); and for death, MI, or severe recurrent ischemia, 1.15 (95% CI, 0.99-1.34). One-year mortality-adjusted HR was 0.99 (95% CI, 0.73-1.33). Among 2711 patients with core laboratory lipid analysis, early statin was associated with higher adjusted risk for death or death or MI at cholesterol levels below treatment guidelines but was more favorable at higher levels.. In this study, there was no relationship between early initiation of statin therapy and improved outcomes although our subset analysis suggests that outcomes after early statin initiation may vary with cholesterol levels. Confirmation of early treatment effects of statins on outcomes awaits the results of adequately powered randomized clinical trials.

Topics: Acute Disease; Aged; Angina, Unstable; Aspirin; Female; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lipoproteins; Male; Middle Aged; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Proportional Hazards Models; Randomized Controlled Trials as Topic; Survival Analysis; Treatment Outcome

Topics: Administration, Oral; Benzodiazepines; Clinical Trials, Phase III as Topic; Hemorrhage; Humans; Myocardial Infarction; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Stroke; Treatment Outcome

Cardiac endothelin-1 (ET-1) levels and ET receptor expression are increased in congestive heart failure (CHF). In order to determine whether this results in increased responsiveness of ET-A or ET-B receptors to ET-1, we evaluated the contractile effects of ET-1 in isolated papillary muscles isolated from hearts of control rats and from rats 4 weeks post myocardial infarction (MI) having received no therapy or chronic quinapril therapy. The ET-1 dose-response was biphasic in normal muscles. The use of the selective ET-A receptor antagonist BQ123 and the selective ET-B receptor antagonist BQ788 revealed that the initial decrease in tension was the result of ET-B receptor stimulation. Blockade of nitric oxide (NO) production with L-NAME abolished the initial decrease in tension. MI resulted in CHF that was partially reversed by quinapril. In MI, the positive inotropic effects of ET-1 were enhanced due to the loss of the initial ET-B receptor mediated decrease in tension, as well as an increase in the positive inotropic effects of ET-A receptors. This was associated with an increase in ET-A and ET-B receptor mRNA and a decrease in cardiac ecNOS protein. Four weeks of therapy with quinapril attenuated the positive inotropic effects of ET-1 and prevented the increase in ET-A receptor mRNA. Although quinapril did not restore the effects of ET-B receptor stimulation or prevent the increase in ET-B mRNA, it did restore cardiac ecNOS protein expression. Thus, the inotropic response to ET-1 is biphasic due to an overall positive inotropic effect of ET-A receptor stimulation and an ET-B receptor mediated decrease in contractility at low ET-1 concentrations which appears to be mediated by cardiac ecNOS (NO). In post-MI CHF, responsiveness to ET-A receptors increases and the ET-B mediated negative inotropic response is lost despite an increase in both receptor subtypes. Quinapril therapy attenuates these effects and normalises cardiac ecNOS protein.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Antihypertensive Agents; Binding, Competitive; Body Weight; Dose-Response Relationship, Drug; Endothelin-1; Endothelium, Vascular; Heart Failure; Hemodynamics; Isoquinolines; Kinetics; Male; Muscles; Myocardial Contraction; Myocardial Infarction; Myocardium; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Oligopeptides; Organ Culture Techniques; Organ Size; Papillary Muscles; Peptides, Cyclic; Piperidines; Protein Binding; Quinapril; Rats; Rats, Wistar; Receptor, Endothelin A; Receptor, Endothelin B; Receptors, Endothelin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tetrahydroisoquinolines; Time Factors; Vasoconstrictor Agents; Viper Venoms

The cardioprotective efficacy of the pyrazolinone-piperidine dipeptide growth hormone secretagogue (GHS) CP-424,391 was studied in an in vivo rabbit model of ischemia and reperfusion. CP-424,391 was administered at 25 mg/kg p.o. x 7 days. Ischemia was induced by left coronary artery occlusion for 30 min, after which the heart was reperfused for 2 h. At the end of reperfusion, animals were euthanized and the infarct size was determined. The area at risk of infarct was not different between the control (45.8+/-3.7%, n=6) and CP-424,391-treated groups (36.9+/-4.3%, n=11). The infarct size of the control animals was 49.5+/-7.1% and was significantly (P<0.05) lower in the CP-424,391-treated group (infarct size=17.3+/-3.0). There was a trend, albeit not significant, for the left ventricular function to recover to a greater extent in CP-424,391-treated rabbits. Thus, the treatment of rabbits for 7 days with CP-424,391 was cardioprotective against ischemia/reperfusion injury.

Topics: Animals; Body Weight; Dose-Response Relationship, Drug; Growth Hormone; Heart Ventricles; Hemodynamics; Insulin-Like Growth Factor I; Male; Myocardial Infarction; Piperidines; Pyrazoles; Rabbits; Reperfusion Injury; Time Factors; Treatment Outcome

The cardioprotective effect of calcitonin gene-related peptide (CGRP) was investigated in an ischemia rat model.. Ischemia-reperfusion injury was provoked by 60 min left main coronary artery occlusion followed by 60 min of reperfusion in anesthetized rats. The transverse slices of ventricles were stained by 2,3,5-triphenyltetrazolium chloride to determine the infarct area. Plasma creatine phosphokinase levels were determined by means of a creatine phosphokinase (CPK) kit. A radioimmunoassay was used to determine plasma CGRP levels.. Intravenous infusion of CGRP (1 nmol . kg-1 . h-1) 10 min before occlusion until the end of reperfusion reduced infarct size by 89 %+/- 5 %. The reduction in infarct size was accompanied by a decrease in circulating levels of creatine phosphokinase. Infusion of the same dose of CGRP commencing from the start of reperfusion until its end induced a 40 % +/- 3 % reduction of the infarct size. The cardioprotective effects of CGRP were blocked by the novel CG RP antagonist BIBN4096BS (20 nmol . kg-1 . h-1). Although cardiac ischemia resulted in an almost 50 % increase in plasma CGRP levels in blood sampled from right cardiac ventricle, intravenous infusion of the CGRP antagonist BIBN4096BS before occlusion until the end of reperfusion had no statistically significant effect on the infarct size.. The present study demonstrates that CGRP is a potent myocardial protective substance.

Topics: Animals; Calcitonin Gene-Related Peptide; Cardiotonic Agents; Creatine Kinase; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Piperazines; Piperidines; Quinazolines; Rats; Rats, Wistar

Topics: Administration, Oral; Aspirin; Death, Sudden, Cardiac; Humans; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Risk Factors

We sought to examine whether the antiarrhythmic effect of E4031 (E), or I(Kr) channel blocker, is affected by beta-adrenergic stimulation using isoproterenol (Iso) or by beta-adrenergic blockade (betaB) using, ONO1101, in a canine myocardial infarction model. Electrophysiologic studies were performed in 10 dogs with 7-day-old myocardial infarctions. Local QT intervals were measured at 47 sites on the infarcted myocardium using a mapping electrode. QT dispersion (QTd), as defined by the coefficient of variation of QT intervals, was obtained. Inducibility of ventricular arrhythmias was examined by programmed stimulation. These procedures were repeated during administration of E, E + Iso, and E + betaB. The effect of prolonging local QT intervals by E was counteracted by Iso, and was accentuated by betaB. The amount of prolongation was dependent on the baseline QT intervals, and QTd showed a tendency to decrease with E, to increase with E + Iso, and significantly decreased with E + betaB. Ventricular tachyarrhythmias were induced in a half of dogs with E + Iso, but were not induced with E + betaB. In the presence of adrenergic activation, I(Kr) blockers may exhibit a decreased antiarrhythmic effect. Beneficial synergism can be expected when an I(Kr) blocker is combined with a beta-blocker in the subacute phase of myocardial infarction.

Topics: Adrenergic beta-Antagonists; Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Disease Models, Animal; Dogs; Drug Therapy, Combination; Electrocardiography; Female; Heart; Heart Ventricles; Male; Morpholines; Myocardial Infarction; Piperidines; Potassium Channel Blockers; Pyridines; Urea

Topics: Adult; Breast Neoplasms; Cerebrovascular Disorders; Drug Costs; Endometrial Neoplasms; Estrogen Antagonists; Estrogens; Female; Fractures, Bone; Humans; Middle Aged; Myocardial Infarction; Osteoporosis, Postmenopausal; Piperidines; Placebos; Pulmonary Embolism; Raloxifene Hydrochloride; Randomized Controlled Trials as Topic; Tamoxifen; Thrombophlebitis

The effects of the extremely selective mu-opioid receptor agonist, [D-Arg2,Lys4]-dermorphin-(1-4)-amide (DALDA), the mu-opioid receptor agonist morphine, the mu/delta agonist D-Ala2, Leu5, Arg6-enkephalin (dalargin), the kappa-opioid receptor agonist spiradoline, and the sigma1-receptor antagonist DuP 734 on ventricular fibrillation threshold (VFT) was investigated in an experimental post-infarction cardiosclerosis model and an immobilization stress-induced model in rats. Both models produced a significant decrease in VFT. The postinfarction cardiosclerosis-induced decrease in VFT was significantly reversed by intravenous administration of dalargin (0.1 mg/kg), DALDA (0.1 mg/kg), or morphine HCl (1.5 mg/kg). Pretreatment with naloxone (0.2 mg/kg) completely eliminated the increase in cardiac electrical stability produced by DALDA. Both spiradoline (8 mg/kg, i.p.) and DuP 734 (1 mg/kg, i.p.) produced a significant increase in VFT in rats with post-infarction cardiosclerosis. This effect of spiradoline was blocked by nor-binaltorphimine. The immobilization stress-induced decrease in VFT was significantly reversed by administration of either DALDA, spiradoline or DuP 734. In conclusion, activation of either mu- or kappa1-opioid receptors or blockade of sigma1-receptors reversed the decrease in VFT in both cardiac compromised models. Since DALDA and dalargin essentially do not cross blood brain barriers, their effects on VFT may be mediated through peripheral mu-opioid receptors.

Topics: Animals; Anti-Arrhythmia Agents; beta-Endorphin; Disease Models, Animal; Dynorphins; Enkephalin, Leucine-2-Alanine; Heart; Immobilization; Ligands; Morphine; Myocardial Infarction; Myocardium; Naloxone; Naltrexone; Narcotic Antagonists; Oligopeptides; Piperidines; Pyrrolidines; Rats; Receptors, Opioid; Receptors, Opioid, delta; Stress, Physiological; Ventricular Fibrillation

Despite progress, atherosclerotic vascular disease remains a major cause of morbidity and mortality. Intravenous therapy with platelet glycoprotein (GP) IIb/IIIa receptor antagonists improves outcome in patients with acute coronary syndromes (ACS). Whether potent long-term antiplatelet therapy with oral GP IIb/IIIa antagonists will further improve outcome at a dose that is tolerable in long-term treatment is unknown.. SYMPHONY (Sibrafiban versus aspirin to Yield Maximum Protection from ischemic Heart events post-acute cOroNary syndromes) was a randomized, double-blind, aspirin-controlled trial with 2 concentration regimens of sibrafiban, an oral peptidomimetic GP IIb/IIIa antagonist, for long-term treatment instead of aspirin in patients after an ACS. Patients were eligible for SYMPHONY if they presented within 7 days of an ACS (>/=20 minutes of ischemic symptoms), had been clinically stable for at least 12 hours, and met one of the following inclusion criteria: ST-segment depression or elevation of at least 0.5 mm or new left bundle branch block with the ACS or elevated creatinine kinase MB more than the upper limit of normal and >3% of total creatine kinase or, if creatine kinase MB was not measured, an elevated level of troponin T or I. Approximately 9000 patients post ACS were randomized 1:1:1 to treatment with either aspirin (80 mg every 12 hours) or high-dose or low-dose sibrafiban every 12 hours. Assignment of tablet strength (3, 4.5, or 6 mg) within the sibrafiban arms was based on body weight and renal function to achieve a target steady-state plasma concentration. The duration of study drug therapy was 90 days. Patients who had intracoronary stenting during the course of the study initially received a blinded stent medication assignment for 2 to 4 weeks based on their initial randomization as follows: aspirin/ticlopidine 250 mg twice daily, low-dose sibrafiban/ticlopidine placebo twice daily, and high-dose sibrafiban/ticlopidine placebo twice daily. After the second interim safety assessment by the Data and Safety Monitoring Board the stent regimen for the low-dose group was modified to include ticlopidine 250 mg twice daily.. The primary efficacy end point of SYMPHONY was the 90-day incidence of a composite of all-cause mortality, myocardial infarction or reinfarction, and severe recurrent ischemia. A clinical events classification committee was established to determine the end points of reinfarction and severe recurrent ischemia. The primary safety end points were the incidence of major bleeding or minor bleeding and the combined incidence of major and minor bleeding. Bleeding classification was done by computer algorithm. Tolerability was assessed by the rate of study drug discontinuation from bleeding.

Topics: Angina, Unstable; Aspirin; Clinical Trials, Phase III as Topic; Double-Blind Method; Humans; Myocardial Infarction; Oximes; Piperidines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Prodrugs; Randomized Controlled Trials as Topic; Research Design; Syndrome; Treatment Outcome

Subendocardial Purkinje myocytes from the 48-hour infarcted heart (IZPCs) have reduced resting potentials, possibly due to altered inwardly rectifying K+ currents IK1. Abnormal depolarization-activated outward K+ currents could contribute to long triangularly shaped action potentials of IZPCs.. We used whole cell patch recordings to compare cesium-sensitive IK1 and 4-aminopyridine (4-AP)-resistant, noninactivating sustained IK between normal Purkinje myocytes (NZPCs) and IZPCs. IZPCs showed decreased net membrane currents. Two IZPC groups were distinguished, based on 4-AP-resistant outward K+ currents. IZPC-I had isochronal IK1 current-voltage relations similar to NZPCs whereas IZPC-II showed significantly reduced IK1 and increased outward plateau currents. To study the sustained IK in the presence of the Class III antiarrhythmic agent E-4031, a two-pulse protocol was used to inactivate transient outward currents, followed by step depolarizations. E-4031-sensitive currents were significantly greater in IZPCs at depolarized potentials (> 0 mV). Similar to NZPCs, IZPC E-4031 currents showed time dependence during depolarization, lack of rectification at positive steps, and voltage-dependent recovery from block.. Decreased IK1 may account for reduced resting potentials in IZPCs. E-4031-sensitive currents in NZPCs, unlike those in canine ventricular myocytes, are sensitive to 4-AP and are larger in IZPCs.

Topics: 4-Aminopyridine; Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Calcium Channel Blockers; Cesium; Data Interpretation, Statistical; Dogs; In Vitro Techniques; Male; Membrane Potentials; Myocardial Infarction; Patch-Clamp Techniques; Piperidines; Potassium Channels; Purkinje Cells; Pyridines

Recent results have shown that the sulfonylurea receptor couples to several types of inward-rectifier potassium (KIR) channels, which suggests that sensitivity to blockade of a pathophysiological phenomenon such as ischemic preconditioning (PC) by glibenclamide may not be the result of this compound selectively blocking the ATP-sensitive potassium (KATP) channel. Therefore, to address this possibility, a role for myocardial KIR v KATP channels in ischemic PC was evaluated in the rat. To test this hypothesis, anesthetized, open-chest, male Wistar rats were assigned to one of seven experimental protocols. Animals assigned to group I (control) received 30 min of occlusion and 2 h of reperfusion. Ischemic PC was produced by 3x5-min occlusion and 2-h reperfusion periods (group II). Terikalant (TK), an inward-rectifier potassium channel blocker, was used to test the role of other K+ channels, most notably the KIR, in the cardioprotective effect of ischemic PC in the rat. TK was given at a dose of 3 mg/kg, i.v., 15 min before the prolonged occlusion and reperfusion periods (group III). In groups IV, V, and VI terikalant (1, 3 and 6 mg/kg, i.v.) was given 15 min before ischemic PC (lowTK+PC, medTK+PC and hiTK+PC, respectively). Group VII consisted of glibenclamide (0.3 mg/kg, i.v.) given 30 min prior to ischemic PC (GLY+PC). Infarct size (IS) as a percent of the area at risk (AAR) was measured using the histochemical stain, 2,3, 5-triphenyltetrazolium chloride. The average IS/AAR for the control was 49.9+/-2.1%. Ischemic PC markedly reduced infarct size (8.6+/-1. 8%; * P<0.05 v control). Terikalant (TK; 1, 3 and 6 mg/kg, i.v.) did not abolish the cardioprotective effect of ischemic PC at any dose (15.5+/-6.4, 16.4+/-5.2 and 8.8+/-1.6%, respectively; * P<0.05 v control). TK itself had no effect on infarct size. GLY completely abolished the cardioprotective effect of ischemic PC (48.2+/-6.4%). In addition, the high dose of TK significantly (P<0.05) increased the action potential duration at 50% repolarization from 48+/-3 to 64+/-4 ms and 30 microM of TK, a concentration which produced a 39% decrease in the inward-rectifier potassium channel current in isolated guinea-pig ventricular myocytes in the whole-cell patch-clamp mode did not block the increase in K ATP current produced by the KATP opener bimakalim (3 microM). These results demonstrate that although the myocardial KATP channel belongs to the K IR superfamily, the endogenous myocardial KIR channel does not m

Topics: Action Potentials; Animals; Anti-Arrhythmia Agents; ATP-Binding Cassette Transporters; Cells, Cultured; Chromans; Electrophysiology; Guinea Pigs; Heart; Hemodynamics; Ischemic Preconditioning, Myocardial; KATP Channels; Male; Myocardial Infarction; Piperidines; Potassium Channels; Potassium Channels, Inwardly Rectifying; Rats; Rats, Wistar

Arginine vasopressin (AVP) has an uncertain role in the pathogenesis of increased myocardial and other regional vascular resistance after cardiac injury. The extreme increase in plasma AVP levels observed in some individuals after myocardial infarction potentially exacerbates already compromised myocardial perfusion. We assessed whether blockade of AVP, by administration of the specific V1-receptor antagonist OPC-21268, can reduce the severity of myocardial injury after embolization in our ovine model of acute myocardial infarction. Embolizations resulted in a pattern of changes in ECG and cardiac enzymes consistent with moderate to severe acute myocardial infarction, resulting in left ventricular dysfunction [left ventricular ejection fraction (LVEF) reduced from 52-53% to 38%]. However, no statistically significant differences were observed between groups in hemodynamic or neurohumoral indices of myocardial damage. By contrast, the hypothalamus-pituitary-adrenal (HPA) response [including plasma AVP (p < 0.01), adrenocorticotropic hormone (ACTH; p < 0.01), and cortisol (p < 0.01)) to embolizations was significantly increased in the sheep infused with OPC-21268. In conclusion, whereas plasma HPA responses differed between the two groups, the similar responses in cardiac enzymes, LVEF, and hemodynamic and neurohumoral factors in both groups does not support a role of V1 receptor-mediated exacerbation of myocardial injury in this model of myocardial infarction. Assessment of different receptor antagonists or examination of other models of cardiac injury may further clarify the role of the markedly increased AVP levels that can occur in myocardial infarction.

Topics: Adrenocorticotropic Hormone; Animals; Antidiuretic Hormone Receptor Antagonists; Arginine Vasopressin; Corticotropin-Releasing Hormone; Female; Halothane; Hemodynamics; Myocardial Infarction; Piperidines; Quinolones; Renin; Sheep

Topics: Animals; Atrial Fibrillation; Heart; Immobilization; Ligands; Male; Myocardial Infarction; Oligopeptides; Piperidines; Pyrrolidines; Rats; Rats, Wistar; Receptors, Opioid; Receptors, Opioid, kappa; Receptors, Opioid, mu; Receptors, sigma; Stress, Physiological

This study was designed to assess the effect of a nonpeptide vasopressin V1-receptor antagonist, OPC-21268, and a vasopressin V2-receptor antagonist, OPC-31260, on hemodynamics in the early phase and the late phase after myocardial infarction in rats. In the early phase, OPC-21268 (30 mg/kg/day) or OPC-31260 (30 mg/kg/day) was orally administered from day 1 to day 5 after the operation; and hemodynamics were measured at day 5, in the late phase from 10 weeks to 11 weeks and measured at the end of 11 weeks. In the early phase, OPC-21268 reduced the left ventricular end-diastolic pressure (LVEDP) concomitantly with the reduction in systemic blood pressure, but did not change LVEDP in the late phase. OPC-31260 reduced LVEDP and central venous pressure in both phases. OPC-21268 improved hemodynamics only in the early phase and OPC-31260 improved it in both phases.

Topics: Administration, Oral; Animals; Antidiuretic Hormone Receptor Antagonists; Benzazepines; Heart Ventricles; Hemodynamics; Male; Myocardial Infarction; Organ Size; Piperidines; Quinolones; Rats; Rats, Wistar; Time Factors; Vasopressins; Ventricular Function, Left

Susceptibility to reentrant tachyarrhythmias and the antiarrhythmic efficacy of class III agents are related more to the duration of the refractory period (ERP) than to the repolarization time (RT). We measured both ERP and RT in a canine model of healing myocardial infarction, and evaluated the effect of a class III agent (E4031) on these parameters and on the inducibility of ventricular tachyarrhythmias. ERP and RT on the unipolar electrogram were measured at several cycle lengths in the normal (NZ) and infarct zones (IZ), respectively, in 10 canine myocardial infarction models and extrastimulation was used to induce ventricular arrhythmias. Measurements were repeated after E4031 administration. At baseline, both ERP and RT were significantly longer in IZ than in NZ with ERP/RT ratio also higher in IZ. This ratio tended to increase at longer cycle lengths. E4031 increased ERP and RT both in NZ and IZ at all cycle lengths, but increased the ERP/RT ratio predominantly in IZ. E4031 prevented induction of sustained VT or VF, which was inducible in 3 out of 10 dogs at baseline, although it facilitated induction of VF in 1 dog with no baseline arrhythmia. By increasing the ERP/RT ratio, class III drugs may shorten the relative refractory period in IZ at the expense of a greater ERP difference created between NZ and IZ.

Topics: Animals; Anti-Arrhythmia Agents; Dogs; Electrophysiology; Female; Heart Conduction System; Humans; Male; Myocardial Infarction; Piperidines; Pyridines; Refractory Period, Electrophysiological

Topics: Angina, Unstable; Animals; Anticoagulants; Antithrombins; Clinical Trials as Topic; Dalteparin; Enoxaparin; Fibrinolytic Agents; Glycine; Heparin, Low-Molecular-Weight; Humans; In Vitro Techniques; Myocardial Infarction; Nadroparin; Piperidines; Thromboembolism

Class III activity has been proposed as a potential mechanism for the treatment of reentrant arrhythmias. The purpose of the present study was to assess the concordance in antiarrhythmic efficacy of MK-499, a selective blocker of IKr, the rapidly activating component of cardiac delayed rectifier K+ current, against programmed ventricular stimulation (PVS)-induced ventricular tachycardias and thrombotically induced lethal ischemic arrhythmias, and to characterize the electrophysiologic determinants of antiarrhythmic efficacy in the canine model of previous myocardial infarction. Single i.v. doses of 1.0, 3.0 and 10.0 micrograms/kg MK-499 were administered to anesthetized dogs with anterior myocardial infarctions. Protection (suppression + stabilization/slowing) vs. PVS-induced ventricular tachycardias occurred in 5/11 (45%) preparations at 1.0 microgram/kg, in 9/12 (75%) preparations at 3.0 micrograms/kg and in 10/11 (91%) preparations at 10.0 micrograms/kg i.v. MK-499. The incidences of lethal ventricular arrhythmias developing in response to thrombotically induced posterolateral myocardial ischemia were 34/40 (85%) in vehicle controls, 7/11 (64%) at 1.0 microgram/kg, 6/12 (50%, P < .05) at 3.0 micrograms/kg and 4/11 (36%, P < .01) at 10.0 micrograms/kg i.v. MK-499. Low-dose i.v. MK-499 prolonged ECG QT interval and increased noninfarct zone and infarct zone ventricular refractoriness. However, there was a poor concordance (56%) between response to PVS with MK-499 and response to thrombotically induced acute myocardial ischemia. Furthermore, different trends of association between site and magnitude of Class III effect and antiarrhythmic efficacy were observed for PVS- vs. ischemia-induced arrhythmias. Hence, although low-dose i.v. MK-499 provided significant protection against both electrically and ischemically triggered arrhythmias in the setting of previous myocardial infarction, protection against PVS-induced ventricular tachycardias was not highly predictive of protection against lethal ischemic arrhythmias in this preparation.

Topics: Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Benzopyrans; Dogs; Electrocardiography; Female; Heart; Male; Myocardial Infarction; Piperidines

The cardioprotective effect of R56865, an Na(+)- and Ca(2+)-overload inhibitor, was studied in 20 regionally ischemic reperfused (I/R) porcine hearts. Ten pigs were treated with a single intravenous (i.v.) injection of 0.4 mg/kg 15 min before occlusion of the distal left anterior descending coronary artery (LAD) for 45 min. Ten other animals served as controls. Infarct size (IS) was determined as percentage of infarcted (tetrazolium method) to ischemic (dye technique) myocardium after 24-h reperfusion. Regional systolic shortening (SS) was determined by sonomicrometry. Fifteen minutes after i.v. administration of R56865, a significant decrease in heart rate (HR) (from 83 +/- 15 to 74 +/- 16 beats/min), dP/dtmax (from 2,033 +/- 604 to 1,822 +/- 524 mm Hg/s), LAD blood flow (BF, from 17 +/- 7 to 14 +/- 7 ml/min), and calculated global myocardial O2 consumption (MVO2) (from 5.9 +/- 0.9 to 5.4 +/- 0.9 ml O2/min x 100 g) was observed. Although this investigational drug attenuated the increase in HR during early reperfusion, the incidence of ventricular fibrillation (VF) was not affected during either ischemia or reperfusion. R56865 reduced IS by 24% from 67.1 +/- 16% (control group) to 50.8 +/- 13%. In addition, this treatment improved systolic shortening after 24-h reperfusion from 6 +/- 8% (control group) to 15 +/- 9%. Our results support the concept that inhibition of intracellular Na(+)- and Ca(2+)-overload is a promising new principle in treatment of myocardial I/R.

Topics: Animals; Benzothiazoles; Blood Pressure; Calcium; Calcium Channel Blockers; Coronary Circulation; Female; Heart Rate; Injections, Intravenous; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Oxygen Consumption; Piperidines; Sodium; Sodium Channel Blockers; Swine; Thiazoles; Ventricular Fibrillation

The electrophysiologic and antifibrillatory properties of NE-10064 were studied in vivo in a conscious canine model of sudden cardiac death. Purpose bred male mongrel dogs weighing 14.5-21.5 kg were anesthetized, and surgical anterior myocardial infarction (MI) was induced by a 2-h occlusion, with reperfusion, of the left anterior descending coronary artery (LAD). Three to 5 days after induction of anterior wall MI, animals were subjected to testing by programmed electrical stimulation (PES). As compared with predrug incidence (12 of 12), NE-10064 (10 mg/kg intravenously, i.v.) reduced (p < 0.05) the incidence (8 of 12) of PES-induced ventricular tachycardia (VT). All but 1 control animal remained inducible after vehicle (5% dextrose in water). The cycle length of induced VT was not prolonged by NE-10064 (0.245 +/- 0.046 s predrug vs. 0.301 +/- 0.060 s postdrug). NE-10064 increased ventricular effective refractory period (VERP 166 +/- 5 ms predrug vs. 194 +/- 13 ms postdrug, p = 0.013), prolonged QTc interval (310 +/- 12 ms predrug vs. 350 +/- 16 ms postdrug, p = 0.004) and prolonged the effective refractory period (ERP) of noninfarcted myocardium (p = 0.045). The drug did not affect ECG-indexes of conduction velocity: QRS and P-R intervals were not affected, nor were activation delay and conduction time of noninfarcted and infarcted myocardium. In the sudden cardiac death protocol, NE-10064 protected (p = 0.018) against ischemia-induced ventricular fibrillation (VF, 75% survival with drug vs. 25% survival without drug). NE-10064 afforded protection (p = 0.040) throughout 14 h posterolateral ischemia in the presence of the previous anterior infarct.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Anti-Arrhythmia Agents; Death, Sudden, Cardiac; Disease Models, Animal; Dogs; Electric Stimulation; Electrocardiography; Electrophysiology; Heart Rate; Hydantoins; Imidazoles; Imidazolidines; Male; Myocardial Infarction; Piperazines; Piperidines; Tachycardia, Ventricular; Ventricular Fibrillation

Bidisomide is a Class Ia/Ib antiarrhythmic agent with activity against ventricular and supraventricular arrhythmias. The potential for bidisomide to increase defibrillation threshold (DFT) was tested in anesthetized dogs with healed left ventricular infarcts (> or = 10 days). Defibrillation patches were attached to each ventricle and shocks were delivered via an external cardioverter/defibrillator. Three groups were studied: placebo (saline), canine therapeutic bidisomide (TB, 2-5 micrograms/mL plasma concentration) and supratherapeutic bidisomide (STB, 6-14 micrograms/mL). Each animal received only one treatment. An abbreviated DFT curve was determined before and after treatment. Heart rate, blood pressure, PR, QRS, infarct size, and hematocrit were also measured before and after treatment. DFT was significantly increased (average +3 to +5 joules [J], P < 0.05) by TB and STB. TB (5/5) did not increase DFT beyond 40 J. In 6/7 experiments, STB did not increase DFT beyond 40 J. Placebo (n = 6) had no significant effect on DFT. Infarct size (mean = 11% of the left ventricle) was not significantly different between groups. Heart rate and QRS were not significantly altered but blood pressure was significantly decreased (16%-31% systolic, 29%-45% diastolic) and hematocrit was significantly increased (19% to 25%) in all groups. PR was significantly increased by STB only.. therapeutic and supratherapeutic doses of bidisomide slightly but significantly increased DFT (3-5 J) in a canine infarcted heart model.

Topics: Animals; Anti-Arrhythmia Agents; Blood Pressure; Dogs; Electric Countershock; Electrocardiography; Heart Rate; Myocardial Infarction; Piperidines; Ventricular Fibrillation

We evaluated the antiarrhythmic efficacy of E-4031, a new class III drug, and compared it with that of conventional class I and II antiarrhythmic agents in terms of electrophysiological actions on refractoriness and conduction in a 7-day-old canine model of myocardial infarction. Sustained monomorphic VT was reproducibly induced in 26 dogs by a premature stimulation method from the right ventricle. Class I drugs (disopyramide, aprindine, flecainide) prevented VT induction in 5 of 13 dogs, and propranolol and E-4031 prevented it in 6 of 6 and 6 of 7 dogs, respectively. The effective refractory period (ERP) was determined at 47 epicardial sites overlying the infarct in each experiment by a S1S2 method. The standard deviation (SD) of the mean ERP of these sites was used as an index of ERP dispersion. The extent of ERP prolongation produced by class I drugs and E-4031 was significantly more marked than that produced by propranolol. However, the SD was increased by class I drugs and E-4031, but not by propranolol. Class I drugs increased the ERP dispersion mainly by an effect on the transmural infarct zone in which the control ERP was more prolonged than in the normal zone. E-4031 tended to prolong the ERP in both the normal and infarct zones, and had a minimal tendency to increase ERP dispersion. In contrast, propranolol decreased the ERP dispersion between zones. Conduction velocity calculated by epicardial mapping was significantly decreased by flecainide, but not by E-4031. We conclude that the antiarrhythmic effect of E-4031 depends largely on its ability to prolong refractoriness without suppressing conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Anti-Arrhythmia Agents; Aprindine; Arrhythmias, Cardiac; Disease Models, Animal; Disopyramide; Dogs; Electrophysiology; Flecainide; Myocardial Infarction; Piperidines; Potassium Channel Blockers; Pyridines; Tachycardia, Ventricular

Class III antiarrhythmic agents such as E-4031 have demonstrated efficacy in preventing and/or terminating malignant ventricular arrhythmias in experimental models. It has recently been suggested that Class III agents might possess additional antiischemic properties that may translate into a reduction in the frequency or severity of arrhythmia. The potential for the Class III antiarrhythmic agent E-4031 to limit the extent of developing myocardial infarction was assessed in a barbiturate-anesthetized canine model of ischemic-reperfusion injury. Untreated control (n = 13) and E-4031-treated animals (n = 8, 300 micrograms/kg, i.v., immediately preceding myocardial ischemia) were subjected to a 90-min period of left circumflex coronary artery occlusion followed by a 5-h period of reperfusion. The predominant hemodynamic effect displayed by E-4031 was a reduction in heart rate throughout the period of coronary artery occlusion and early reperfusion. Areas at risk of infarction, expressed as percentages of left ventricle, were equivalent in the control and E-4031 treatment groups (38.5 +/- 1.0 and 34.6 +/- 1.9%, respectively). Posterolateral myocardial infarct sizes, expressed either as percentages of risk area or of total left ventricle, were reduced slightly but not significantly in the E-4031 treatment group compared to the control group (35.2 +/- 5.6 and 45.4 +/- 3.0% of risk area, respectively; 12.7 +/- 2.4 and 17.6 +/- 1.4% of left ventricle, respectively). Regional myocardial blood flows in nonischemic and central ischemic zones of myocardium did not differ significantly between the control and E-4031 treatment groups before and during the period of coronary artery occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Anti-Arrhythmia Agents; Coronary Circulation; Dogs; Female; Hemodynamics; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Piperidines; Pyridines; Ventricular Fibrillation

The acute tolerability of rapid infusions of bidisomide or disopyramide was evaluated in normal conscious dogs and in conscious dogs 48 h after the creation of myocardial infarctions (MIs). Both drugs were given in total doses of 15 mg/kg (1.5 x the canine antiarrhythmic dose for each drug). Bidisomide was well tolerated at infusion rates of 3, 5, 11, and 15 mg/kg/min by normal dogs. Disopyramide was well tolerated, except for anticholinergic effects, by normal dogs given infusions at rates of 1.5 and 3 mg/kg/min. Disopyramide caused a ventricular arrhythmia at 4.5 mg/kg/min in one dog, however. Bidisomide (15 mg/kg/min) was well tolerated and antiarrhythmic in dogs with infarctions. Disopyramide (3 and 4.5 mg/kg/min) was lethal in dogs that had myocardial infarctions. A 1 mg/kg/min infusion rate of disopyramide was antiarrhythmic and well tolerated, except for anticholinergic effects, in the post-MI dogs. Both drugs prolonged the ECG lead II P duration, PR interval (bidisomide more so than disopyramide), and QRS duration. Both bidisomide and disopyramide shifted the mean electrical axis of the QRS complex from a right axis deviation to the normal range in dogs with infarctions. The data indicated that the desired cardiac electropharmacologic effects of bidisomide can be achieved in a 1 min infusion. Normal dogs, and especially dogs with infarctions, revealed the potential hazards of rapidly infusing disopyramide.

Topics: Animals; Anti-Arrhythmia Agents; Disopyramide; Dogs; Dose-Response Relationship, Drug; Drug Tolerance; Electrocardiography; Female; Infusions, Intravenous; Male; Myocardial Infarction; Piperidines

Effects of pirmenol on electrical induction of sustained ventricular tachycardia (VT) were examined in 14 dogs with 7-day-old myocardial infarctions. Before administration of the drug, sustained VT was induced in 8 of 14 dogs. After administration of 3 mg/kg pirmenol, induction of VT was suppressed in 2 dogs but remained inducible in 6 dogs. After cumulative administration of 5 mg/kg pirmenol, VT was no longer inducible in 3 dogs but in the other 3 dogs VTs were still inducible at increased cycle lengths. After 7 mg/kg pirmenol, VT was not inducible in the remaining three dogs. Arrhythmias could not be provoked in any postinfarction dogs after pirmenol administration. Plasma concentrations after sequential and cumulative administration of 3, 5, and 7 mg/kg pirmenol averaged 0.43, 0.65, and 1.15 micrograms/ml, respectively. Administration of pirmenol increased the effective refractory period (ERP) and paced QRS duration in both the normal and infarcted ventricular myocardium. In the infarcted myocardium, prolongation of the ERP for the second and third extrastimuli was greater than for the first one (p less than 0.05). Results indicate that pirmenol is effective for prevention of sustained VT owing to prolongation of both the ERP and conduction time in recent myocardial infarction.

Topics: Animals; Anti-Arrhythmia Agents; Dogs; Electric Stimulation; Electrocardiography; Electrophysiology; Heart Ventricles; Myocardial Infarction; Piperidines; Tachycardia; Ventricular Function

Effects of pirmenol hydrochloride and lidocaine hydrochloride on intraventricular conduction were examined in the infarcted heart of anesthetized dogs. The effects of the drugs on the excitation induced by ventricular stimulations were determined with coupling intervals between 150 and 1,000 ms. Effects of the drugs on the His bundle electrocardiograms were also examined. Pirmenol in doses of 1-5 mg/kg prolonged the conduction time in the infarcted zones over a wide range of coupling intervals. Pirmenol at 5 mg/kg blocked the delayed conduction at a short coupling interval in the infarcted zones. The effect of pirmenol on the conduction time in the normal zone was slight. Lidocaine in doses of 3 and 10 mg/kg prolonged the conduction time in the infarcted zone at a short coupling interval. Pirmenol did not significantly prolong PQ or AH interval. In conclusion, pirmenol selectively depressed the delayed conduction in the infarcted zone, which could result in a reentrant pathway. The effect of pirmenol on delayed conduction was dependent on the coupling interval and was quite different from that of lidocaine.

Topics: Animals; Anti-Arrhythmia Agents; Bundle of His; Dogs; Electric Conductivity; Electrocardiography; Heart Conduction System; Lidocaine; Myocardial Infarction; Piperidines

A novel series of 4-[N-methyl-N-[(E)-3-[4-(methylsulfonyl)phenyl]-2- propenoyl]amino]benzenesulfonamides has been prepared and evaluated as membrane-bound phospholipase A2 inhibitors. A structure-activity relationship study indicated that the optimum potency was realized with the N-(phenylalkyl)piperidine derivatives 3 and 4. These compounds inhibited the liberation of arachidonic acid from the rabbit heart membrane fraction with IC30 values of 0.028 and 0.009 microM, respectively. Several compounds (3, 4, and 28), which proved to be potent inhibitors in vitro, significantly reduced the size of myocardial infarction in coronary occluded rats by iv administrations prior to the ligation. N-(1-Benzyl-4-piperidinyl)-4-[N-methyl-N-[(E)-3-[ 4-(methylsulfonyl)phenyl]-2-propenoyl]amino]-benzenesulfonamide (3, ER-3826), which showed the protective in vivo effects at doses higher than 0.3 mg/kg iv, was finally chosen as a leading candidate.

Topics: Animals; Benzene Derivatives; Cell Membrane; Chemical Phenomena; Chemistry; Enzyme Inhibitors; Heart; Male; Myocardial Infarction; Phospholipases A; Phospholipases A2; Piperidines; Rabbits; Rats; Rats, Inbred Strains; Structure-Activity Relationship; Sulfonamides

The antiarrhythmic efficacy of a new and potent class III agent E4031 [1-[2-(6-methyl-2-pyridyl)-ethyl]-4-(4- methylsulfonylaminobenzoyl)piperidine] was evaluated in several canine models of recent myocardial infarction. In anesthetized dogs with baseline inducible ventricular arrhythmias studied 4-10 days after anterior myocardial infarction, 30-300 micrograms/kg i.v. E4031 suppressed induction of ventricular tachyarrhythmias by programmed ventricular stimulation in 7 of 10 animals tested, while significantly prolonging refractoriness in both noninfarcted and infarcted ventricular myocardium. The incidence of lethal ischemic ventricular arrhythmias developing in response to acute posterolateral myocardial ischemia in the presence of previous anterior infarction was reduced from 10 of 10 (100%) in a vehicle pretreatment group to 3 of 10 (30%, p less than 0.01) in an E4031 (300 micrograms/kg intravenously, i.v.) pretreatment group. Neither the sizes of the underlying anterior myocardial infarctions (26.9 +/- 3.7 vs. 33.2 +/- 2.1% of left ventricle) nor the times to development of acute posterolateral myocardial ischemia (43 +/- 11 vs. 40 +/- 8 min) differed significantly between the vehicle and E4031 pretreatment groups, respectively, suggesting that the reduction in the incidence of lethal ischemic arrhythmias in the E4031 pretreatment group was not due to smaller underlying, electrically unstable myocardial substrates nor to a delay in onset of the acute ischemic insult. In conscious dogs with spontaneous ventricular ectopy at 48 h after myocardial infarction and in anesthetized dogs with no baseline inducible arrhythmias at 4-10 days after myocardial infarction, E4031 (30-3,000 micrograms/kg i.v.) produced no facilitation or aggravation of spontaneous or inducible ventricular arrhythmias. These findings suggest that pharmacologic agents such as E4031 that increase ventricular refractoriness (class III electrophysiologic activity) may provide significant protection against development of malignant ischemic ventricular arrhythmias in the setting of previous myocardial infarction.

Topics: Anesthesia; Animals; Anti-Arrhythmia Agents; Blood Pressure; Chloralose; Dogs; Electric Stimulation; Electrocardiography; Electrophysiology; Female; Heart; Male; Myocardial Infarction; Piperidines; Pyridines; Refractory Period, Electrophysiological

Effects of E-4031, a class III antiarrhythmic agent, on re-entrant ventricular arrhythmias were studied in eight dogs with a 7-day-old myocardial infarction. Epicardial mapping and local refractory periods were obtained using 47-channel bipolar electrodes attached to the epicardium. The induction of sustained ventricular tachycardia by programmed electrical stimulation was not suppressed by i.v. infusion of E-4031 at 1 microgram/kg/min, but was suppressed markedly by infusion at 10 micrograms/kg/min in six of seven dogs. During the infusion of E-4031 at 10 micrograms/kg/min, epicardial conduction velocity in the normal ventricle did not change (0.7 +/- 0.12 to 0.71 +/- 0.13 m/sec, n = 6), whereas slowed conduction in the infarct zone improved (0.58 +/- 0.10 to 0.77 +/- 0.13 m/sec, n = 6). E-4031 at 10 micrograms/kg/min prolonged effective refractory periods (ERP) in the normal zone (139 +/- 8 to 164 +/- 18 msec, P less than .01, n = 8), nontransmural infarct zone (145 +/- 7 to 177 +/- 15 msec, P less than .01, n = 8) and transmural infarct zone (156 +/- 14 to 191 +/- 22 msec, P less than .01, n = 8). The degrees of ERP prolongation were almost equal in all zones. On epicardial mapping, the areas of longer ERP and delayed conduction were observed to become inexcitable after the administration of E-4031. These results demonstrated that E-4031 effectively prevented the induction of re-entrant ventricular tachycardia in canine myocardial infarction model, and suggested that E-4031 rendered re-entrant circuits inexcitable by marked ERP prolongation in both normal and infarct zones.

Topics: Animals; Anti-Arrhythmia Agents; Dogs; Electric Stimulation; Electrodes; Electrophysiology; Heart Conduction System; Infusions, Intravenous; Myocardial Infarction; Piperidines; Pyridines; Tachycardia

Clinical safety and hemodynamic repercussions were studied after administration of six class I antiarrhythmics (xylocaine, ajmaline, mexiletine, lorcainide, indecainide and tocainide) to patients presenting acute myocardial infarction without complications. The hemodynamic parameters monitored generally followed the same trends. A significant decrease of more than 10 per cent of the initial value was seen in systolic blood flow after injection of lorcainide, indecainide and tocainide. Peripheral vascular resistance increased moderately. Pulmonary capillary pressure increased by more than 40 per cent of the starting value after administration of mexiletine, indecainide and tocainide (significant increase in case of mexiletine). These changes in patients presenting infarction without complications are not of clinical importance. There were, however, two very severe cases of hemodynamic reaction after administration of mexiletine. Other signs of intolerance were seen, but they were of minor importance and administration of the drugs was not interrupted. Xylocaine and ajmaline produced the smallest depression of left ventricular functional activity in these patients.

Topics: Ajmaline; Anti-Arrhythmia Agents; Benzeneacetamides; Fluorenes; Hemodynamics; Lidocaine; Mexiletine; Myocardial Infarction; Piperidines; Tocainide

The effect of flecainide in 24 patients with inducible sustained ventricular arrhythmia and a history of remote myocardial infarction was determined. Flecainide was administered in oral doses individually adjusted to suppress all spontaneous ventricular tachycardia and 80% of ventricular premature complexes on 24 hour ambulatory (Holter) electrocardiography. Antiarrhythmic therapy, as assessed by Holter monitoring, was adequate in 20 (83%) of the study patients at a mean dose of 144 +/- 28 mg every 12 hours; the mean plasma flecainide level was 583 +/- 329 ng/ml. In 18 patients, the mean sinus cycle length, sinus node recovery time and atrial, atrioventricular nodal and ventricular refractory periods were unchanged. The AH interval increased by 15 +/- 15%, the HV interval by 35 +/- 32% and the QRS duration by 24 +/- 21%. Toxicity or failure to suppress ventricular premature complexes and ventricular tachycardia by Holter monitoring precluded electrophysiologic study with flecainide in four patients; two patients refused electrophysiologic study with flecainide for nonmedical reasons. Ventricular tachycardia was not inducible in 4 (22%) of 18 patients receiving flecainide. Sustained arrhythmia remained inducible in 14 patients (78%) despite evidence of antiarrhythmic efficacy on Holter monitoring, but the rate of the induced ventricular tachycardia was slower and symptoms were alleviated during ventricular tachycardia in 10 (56%) of 18 patients. The 4 patients who had no inducible ventricular tachycardia with flecainide, and the 10 patients who had inducible ventricular tachycardia with a longer cycle length and alleviation of their symptoms, have been followed up as outpatients for 16 +/- 7 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Arrhythmias, Cardiac; Cardiac Pacing, Artificial; Electrocardiography; Female; Flecainide; Follow-Up Studies; Heart Ventricles; Humans; Male; Middle Aged; Monitoring, Physiologic; Myocardial Infarction; Piperidines; Time Factors

The electrophysiologic actions of pirmenol, an investigational class I antiarrhythmic agent, were evaluated in eight anesthetized dogs, 5 to 10 days after anterior myocardial infarction. Before administration of the drug, programmed ventricular stimulation failed to initiate nonsustained or sustained ventricular tachyarrhythmias (VT) in any of the postinfarction dogs. After the cumulative administration of 2.5, 5.0, and 10.0 mg/kg pirmenol, programmed stimulation initiated sustained VT in six of the eight postinfarction dogs tested, with one additional dog responding with reproducible nonsustained VT (15 to 20 monomorphic complexes) after pirmenol administration. Only one of eight postinfarction dogs tested remained noninducible throughout the pirmenol dosing schedule. Administration of pirmenol tended to increase ventricular excitation thresholds, relative (p less than 0.05 after 10 mg/kg) and effective refractory periods in ischemically injured ventricular myocardium, and increased the difference or disparity in relative (p less than 0.05 after 5.0 and 10.0 mg/kg) and effective (p less than 0.01 after 2.5, 5, and 10, mg/kg) refractory periods between ischemically injured and normal noninjured ventricular myocardium. These findings suggest a potential for the provocation or aggravation of ventricular arrhythmias by pirmenol in the setting of recent myocardial infarction.

Topics: Animals; Anti-Arrhythmia Agents; Cardiac Pacing, Artificial; Dogs; Electrophysiology; Heart; Heart Conduction System; Male; Myocardial Infarction; Piperidines; Tachycardia

In the serum basic drugs are principally bound to alpha1-acid glycoprotein (AAG). Following acute myocardial infarction it has been shown that the levels of AAG rise. The serum levels of total protein, albumin, AAG and the protein binding of 2 antiarrhythmic drugs which are bases, disopyramide and flecainide, was measured in vitro with blood samples from eleven patients taken over the first 5 days following myocardial infarction. Mean AAG levels significantly increased from 1.04 g/l on Day 1 to 1.80 g/l on Day 5. The binding of disopyramide, which is highly bound, rose from 80% to 87%, representing a 35% decrease in free drug concentration. In contrast the binding of flecainide fell from 61% to 53%, a 20% increase in free drug concentration. These data suggest that although the binding of strongly bound drugs responds appropriately to increases in binding protein after acute myocardial infarction, poorly bound drugs are displaced from binding sites possibly by endogenous substances. Since the pharmacological effects of a drug are related to its free (unbound) concentration, the changes in the proportions of free to bound drug after myocardial infarction may have important clinical implications.

Topics: Aged; Anti-Arrhythmia Agents; Blood Proteins; Disopyramide; Female; Flecainide; Humans; Male; Middle Aged; Myocardial Infarction; Orosomucoid; Piperidines; Protein Binding; Serum Albumin

The electrophysiological effects of flecainide, 0.1, 0.5 and 1.0 mg/l, on action potential characteristics were examined in normal Purkinje fibers and Purkinje fibers surviving infarction, at stimulation cycle lengths of 1000 and 300 ms. Overshoot, amplitude and dV/dtmax were reduced significantly in a dose-dependent manner by flecainide in both normal Purkinje fibers and Purkinje fibers surviving infarction. Action potential duration was shortened by flecainide to a greater extent: at the cycle length of 1000 ms compared to 300 ms; at 50% repolarization compared to 90%; and in normal preparations compared to infarcted preparations. Activation time was increased by flecainide in a dose-dependent manner in both types of preparations. This effect was enhanced at the shorter cycle length. In both normal and infarcted preparations, flecainide shortened the ERP of those having a longer initial ERP and lengthened those with a shorter ERP. This effect was significant only at the stimulation cycle length of 1000 ms. This study indicates that flecainide has properties unique and different from traditional antiarrhythmic drugs.

Topics: Action Potentials; Animals; Dogs; Electrophysiology; Female; Flecainide; Heart Conduction System; In Vitro Techniques; Male; Microelectrodes; Myocardial Infarction; Piperidines; Purkinje Fibers

The haemodynamic effects of flecainide were compared in three different subsets of patients with documented coronary disease. Ten patients (A) had no heart failure, 5 patients were on beta blockers (B) and 5 patients had overt heart failure (C). Flecainide was associated with negative inotropic effects that were relatively more pronounced in patients with left ventricular dysfunction: pulmonary wedge pressure increased by 27% in A, by 31% in B and by 42% in C; left ventricular stroke volume and stroke work decreased respectively by 10 and 12% in A, 21 and 19% in B, 26 and 28% in C. Ejection fraction decreased by 9% in A, 13% in B and 20% in C, in relation with an increase in end systolic volume (+9% in A, +10% in B and +5% in C). Absolute changes, however, were not significantly different from one group to another except for the increase of systemic vascular resistance which was more pronounced in C as compared with the other groups. The myocardial depression was also confirmed by the fall in dP/dt that was maximal at the end of injection; dP/dt remained depressed 15 min later despite some improvement. Flecainide thus exerts negative inotropic effects that are maximal at the end of infusion and may be of importance in patients with established left ventricular dysfunction.

Topics: Adult; Aged; Blood Pressure; Coronary Disease; Electrocardiography; Female; Flecainide; Heart Rate; Hemodynamics; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Piperidines; Stroke Volume; Vascular Resistance

Hemodynamic and ECG effects of intravenous flecainide were assessed in 10 patients with acute myocardial infarction and no symptoms or signs of heart failure. The dose was 2 mg/kg injected over a 15-minute period. R-R interval did not change, but PR interval and QRS increased significantly, 28% (p less than 0.0005) and 20% (p less than 0.05), respectively. Duration of P wave also increased significantly, 15% (p less than 0.02). Pulmonary wedge pressure increased 29% (p less than 0.005) and cardiac index and left ventricular stroke work index decreased 9% (p less than 0.05) and 20% (p less than 0.05), respectively. No significant change in mean aortic pressure and systemic vascular resistance occurred. Thus, intravenous flecainide has a mild and transient negative inotropic effect in patients with noncomplicated acute myocardial infarction. It did not induce ventricular failure in this group of patients but should be administered cautiously to patients with overt heart failure or severe conduction defects.

Topics: Adult; Electrocardiography; Female; Flecainide; Heart Conduction System; Hemodynamics; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Piperidines

Nonsustained ventricular tachycardia (VT) in the late period (7 to 21 days) after myocardial infarction (MI) is reported to be a predictor of sudden death. Patients with 3-beat VT on Holter monitoring in the late infarction period would be suspected to demonstrate electrical instability on electrophysiologic studies. Forty-seven patients were identified as having at least 3-beat VT on Holter monitoring. Eighteen patients refused electrophysiologic studies or were not referred. Eight patients died; 3 were sudden deaths in 13 +/- 5 months, a 17% incidence. Twenty-nine patients underwent invasive electrophysiologic studies and 28 had inducible VT, 18 sustained and 10 nonsustained. Lorcainide prevented VT induction in 21 of the 28 patients, whereas 12 of the 22 patients studied on procainamide were protected. Lidocaine, tested in 21 patients, prevented VT induction in only 5. Lorcainide and procainamide prolonged refractoriness in those patients protected at programmed electrical stimulation (PES), whereas the QT interval was prolonged in patients in whom VT could still be induced. Twenty-seven of the 28 patients were placed on drugs predicted to be effective by PES studies, 19 on lorcainide. After a mean follow-up of 12.5 +/- 4 months the patient with noninducible arrhythmia is alive and 26 of the 28 patients with inducible arrhythmia are alive and well. Two patients died, 1 of stroke and 1 of pump failure after a second MI. No sudden deaths were observed in this group. Two patients had breakthrough arrhythmias and were treated by alternative antiarrhythmic therapy that was also effective on initial electrophysiologic studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aged; Anti-Arrhythmia Agents; Benzeneacetamides; Blood Pressure; Death, Sudden; Drug Evaluation; Electrocardiography; Female; Heart Ventricles; Humans; Lidocaine; Male; Middle Aged; Myocardial Infarction; Piperidines; Procainamide; Risk; Tachycardia

During a one-week short-term in-hospital period, 60 patients with chronic ventricular arrhythmias were treated with 200 mg flecainide twice a day. Flecainide reduced premature ventricular complexes (PVCs) by more than 85% without causing important side-effects in 47 patients, who entered a one-year follow-up period and were followed with bimonthly 24-h ECGs. Median PVC-frequency remained reduced by more than 99% during the follow-up period. Repetitive ventricular beats and ventricular tachycardia were present in 83% and 42% of patients, respectively, before flecainide. During follow-up, these arrhythmias were seen in less than 32% and less than 10% of patients, respectively, at each 24-h ECG. Furthermore, the mean number of hours with repetitive ventricular beats and ventricular tachycardia remained reduced by more than 76% and more than 79%, respectively, throughout the follow-up period. Ventricular arrhythmias remained suppressed despite a gradual reduction in flecainide dosages (to a median of 300 mg day-1) and flecainide plasma levels. In nine out of 47 patients, an increase in ventricular arrhythmias above baseline values on one or more occasions was observed. During a flecainide withdrawal period, a 65-fold increase in median PVC-frequency was observed and ventricular tachycardia reappeared in 18 patients. Subjective side-effects were acceptable except for two patients. During the follow-up period, one patient developed reversible heart failure and sinus node dysfunction. During the total study period, four patients, with either severe coronary artery disease (2) or cardiomyopathy (2) developed lethal arrhythmias (3) or ischaemic events (1). We conclude that prolonged flecainide treatment is effective in a high proportion of patients with chronic ventricular arrhythmias. In some patients an arrhythmogenic effect may occur.

Topics: Adult; Aged; Arrhythmias, Cardiac; Chronic Disease; Dizziness; Drug Evaluation; Electrocardiography; Female; Flecainide; Follow-Up Studies; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Time Factors

Repetitive extrasystole and fibrillation thresholds were assessed by various methods of programmed atrial and ventricular stimulation using intracavitary bipolar electrode catheters and a microcomputer based 3-channel stimulator as previously described. "2nd Phase" ventricular arrhythmias were produced by ligation of the left descending coronary artery. 2,5-Bis-(2,2,2-trifluoroethoxy)-N-(2-piperidylmethyl)benzamide acetate (flecainide, R 818, Tambocor) caused a significant increase of the atrial and ventricular fibrillation thresholds. The antifibrillatory action was similar in atrial and ventricular tissues. "2nd Phase" ventricular arrhythmias were dose-dependently reduced or abolished completely. Similar doses were required to suppress spontaneous arrhythmic activity and to increase the fibrillation thresholds. Thus, flecainide proved to be a powerful antiarrhythmic agent with strong antifibrillatory properties in therapeutic doses. It may be a promising drug for the treatment of atrial and ventricular reentrant arrhythmias.

Topics: Animals; Anti-Arrhythmia Agents; Cardiac Complexes, Premature; Dogs; Electric Stimulation; Female; Flecainide; Heart; Male; Myocardial Infarction; Piperidines; Ventricular Fibrillation

Topics: Adult; Aged; Arrhythmias, Cardiac; Benzeneacetamides; Drug Evaluation; Female; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines

Topics: Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Dogs; Flecainide; Heart Ventricles; Myocardial Infarction; Piperidines

Clinical and experimental studies indicate that ventricular arrhythmias, especially ventricular fibrillation, are in almost all cases the mechanism for sudden death occurring during the first 24 hours after the onset of an ischaemic myocardial event. Therefore a higher survival rate seems to depend on advances in antiarrhythmic therapy. The present study investigates the efficacy of the new local anaesthetic compound Flecainide in reducing or preventing ventricular arrhythmias and primary ventricular fibrillation, using a standardized experimental canine preparation. Our findings demonstrate that ventricular arrhythmias due to severe transmural myocardial infarction are reduced by 80-90% following the application of Flecainide. In some cases a complete abolition of the arrhythmias can be observed. The striking reduction in ventricular ectopics includes decreases in ventricular salves and R-on-T phenomena, which may lead to sudden death by precipitating ventricular fibrillation. The beneficial antiarrhythmic and antifibrillatory actions of Flecainide affect only the arrhythmias resulting from transmural necrosis of the myocardium ("in-hospital arrhythmias", 2nd-phase arrhythmias"), whereas the incidence of early ventricular arrhythmias, especially ventricular fibrillation occurring in the very inception of myocardial ischaemia ("pre-hospital arrhythmias", "1st-phase arrhythmias") is not prevented. Changes in hemodynamics and contractility due to Flecainide are not severe, even in myocardial infarction. Thus, our results indicate that the application of Flecainide in acute myocardial infarction in man may be successful in reducing therapy-resistant ventricular dysrhythmias.

Topics: Animals; Arrhythmias, Cardiac; Dogs; Flecainide; Heart Rate; Hemodynamics; Myocardial Infarction; Oxygen Consumption; Piperidines

Lorcainide hydrochloride given at the doses of 150 mg i.v. proved to be well tolerated at the acute stage of a myocardial infarction; the subjective signs were benign and never prevented us from completing the injection. The haemodynamic changes reflect some depressive effects on the myocardial function. Most of the observed changes are transient, and when significant from the statistical point of view, they remain very mild: the cardiac output decreased from 3.4 to 3.2 l/min per m2, the stroke index from 46 to 41 ml/m2, the pulmonary wedge pressure increases from 6.6 to 8.4 mm Hg (mean values). Lorcainide hydrochloride may thus be used as an antiarrhythmic drug in acute myocardial infarction.

Topics: Anti-Arrhythmia Agents; Benzeneacetamides; Hemodynamics; Humans; Injections, Intravenous; Myocardial Infarction; Piperidines

Topics: Acute Disease; Animals; Arrhythmias, Cardiac; Dogs; Flecainide; Lidocaine; Myocardial Infarction; Piperidines

Topics: Animals; Biological Transport, Active; Disease Models, Animal; Female; Heart; Isoproterenol; Male; Myocardial Infarction; Myocardium; Perhexiline; Piperidines; Rats; Rats, Inbred Strains; Rubidium

The long-term anti-arrhythmic efficacy of lorcainide (R15 889) was studied in 20 ambulatory postmyocardial infarction patients. Lorcainide reduced the frequency of ventricular ectopic beats by more than 70% and 90% in 17 and 11 of the patients respectively. The anti-arrhythmic response improved with long-term administration of the drug. Fourteen patients complained of insomnia during the early stages of the study, but this side-effect waned later on. On electrocardiographic examination, the P-R interval, QTc interval and QRS duration were prolonged, and T-wave changes were noted while the patients were receiving lorcainide. Lorcainide seems to be a useful addition to the available anti-arrhythmic agents, and should form part of the armamentarium against ventricular ectopic activity.

Topics: Adult; Aged; Arrhythmias, Cardiac; Benzeneacetamides; Electrocardiography; Humans; Male; Middle Aged; Myocardial Infarction; Piperidines; Ventricular Fibrillation

Perhexiline maleate at a dose of 400 mg three times daily for 2 days administered to normal dogs altered the relative regional transmural resistance so that during reduced coronary flow the endocardium:epicardium (endo:epi) ratio is increased. In the presence of acute myocardial infarction heart rate was significantly lower and the endo:epi ratio of perfused areas was increased when coronary flow was normal. A linear relationship was observed between the endo:epi ratio and the concentration of perhexiline in plasma, and its monohydroxyl metabolite in plasma. The results suggest that the mechanism of action of the drug is due to redistribution of a limited coronary flow.

Topics: Animals; Blood Pressure; Coronary Circulation; Dogs; Dose-Response Relationship, Drug; Heart Rate; Myocardial Infarction; Perhexiline; Piperidines

A five-year personal experience of the use of perhexiline maleate (Pexid) in the treatment of severe angina pectoris is presented. Ninety-four patients, all severely incapacitated by cardiac pain, received perhexiline maleate for an average period of 12.2 months. Perhexiline maleate was used either alone or, more commonly, in conjuction with other antianginal therapy, such as beta-adrenergic receptor blocking agents. The results demonstrate that perhexiline maleate is a very effective agent which appears to be safe for long-term usage. Side effects have been frequent, and occasionally bothersome, but all have been transient and dose-dependent. The possibility that the regimens of treatment may materially improve long-term prognosis is raised.

Topics: Adrenergic beta-Antagonists; Adult; Aged; Angina Pectoris; Australia; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Myocardial Infarction; Perhexiline; Piperidines; Prognosis

Topics: Aged; Coronary Disease; Female; Humans; Male; Middle Aged; Myocardial Infarction; Papilledema; Perhexiline; Piperidines

The effects of perhexiline on survival time and infarct size were studied in three animal models. Dogs pretreated orally with perhexiline, 200 mg/day/14 days, and monitored under anesthesia for 30 hours after ligation of the left anterior descending coronary artery (LAD) had infarct weights of 9.1+/-1.9 g as compared to 15.2+/-1.0 g in paired untreated controls (P less than .02). Twelve of 15 perhexiline-pretreated dogs survived the duration of these studies while only 5 of 15 control animals survived for the same period of time (P less than .05). Serum creatine phosphokinase activity was significantly lower in the treated dogs at 9, 12 and 15 hours after ligation (P less than .05). Conscious dogs, pretreated orally with perhexiline 200 mg/day/7 days or 400 mg/day/7 days and monitored without anesthesia or analgesia for 72 hours after coronary ligation had smaller infarcts (P200=26+/-5; P400=26+/-4; C=39+/-5 g; P less than .05) lower plasma peak creatine phosphokinase activity (P less than .05) and reduced heart rate (P400=198+/-8; C=226+/-8 beats/min; P less than .05) and reduced incidence of ventricular ectopic beats (P less than .05). In pentobarbital anesthetized open-chest dogs, perhexiline (3 mg/kg i.v.) reduced the sum of S-T segment elevation after left anterior descending coronary artery occlusion from 32+/-3 to 14+/-1 mV (P less than .001); this effect was associated with and/or preceded by a reduction in arterial pressure (101+/-4 to 78+/-5 mm Hg; P less than .001) and heart rate (151+/-8 to 138+/-7 beats/min P less than .025; Circumflex flow increased from 38+/-4 to 83+/-8 ml/min (P less than .01). In noninfarcted open-chest dogs, perhexiline administration (3 mg/kg i.v.) resulted in increases in coronary blood flow, narrowing of arterial-coronary sinus O2 difference and a 14% reduction in myocardial O2 consumption. The protective effects of perhexiline on the ischemic myocardium appear to result from reductions in heart rate and associated decrease in myocardial O2 demand as well as an antiarrhythmic effect.

Topics: Animals; Arrhythmias, Cardiac; Blood Pressure; Coronary Vessels; Creatine Kinase; Dogs; Electrocardiography; Female; Heart; Heart Rate; Male; Myocardial Infarction; Myocardium; Oxygen Consumption; Perhexiline; Piperidines; Time Factors

1 The chronotropic and inotropic properties of U.K. 14275, a phosphodiesterase inhibitor were assessed in patients with coronary heart disease. 2 Left ventricular function was assessed in eight patients with acute myocardial infarction using the non-invasive measurement of systolic time intervals. 3 Twelve patients with angina pectoris were studied during diagnostic coronary arteriography. Left ventricular function was assessed using a high fidelity catheter tipped transducer in the left ventricle. 4 In both groups of patients U.K. 14275 infused intravenously in doses of 32, 64, 128 and 256 microgram kg-1 bodyweight min-1 enhanced the contractile state of the left ventricle without altering the heart rate.

Topics: Coronary Disease; Hemodynamics; Humans; Male; Myocardial Contraction; Myocardial Infarction; Phosphodiesterase Inhibitors; Piperidines; Quinazolines

Topics: Humans; Male; Middle Aged; Myocardial Infarction; Perhexiline; Peripheral Nervous System Diseases; Piperidines; Schwann Cells

Topics: Aged; Basal Ganglia Diseases; Coronary Disease; Humans; Male; Maleates; Myocardial Infarction; Perhexiline; Piperidines

Topics: Acute Disease; Aminopyrine; Analgesics; Anti-Arrhythmia Agents; Anticoagulants; Autonomic Agents; Benperidol; Cardiac Glycosides; Chlorpromazine; Diphenhydramine; Drug Combinations; Fentanyl; Heart Function Tests; Hemodynamics; Humans; Injections, Intramuscular; Injections, Intravenous; Myocardial Infarction; Piperidines; Time Factors; Vasodilator Agents

Topics: Acute Disease; Analgesics; Drug Tolerance; Humans; Ketones; Meperidine; Morphine; Myocardial Infarction; Pentazocine; Piperidines

Topics: Angina Pectoris; Benzophenones; Coronary Disease; Humans; Myocardial Infarction; Piperidines; Pyrazoles; Quaternary Ammonium Compounds; Sulfonic Acids

Topics: Analgesia; Arteriosclerosis; Biomedical Research; Double-Blind Method; Drug Therapy; Geriatrics; Humans; Meperidine; Morphine; Myocardial Infarction; Pain; Pharmacology; Piperidines; Transplantation, Homologous

Topics: Analgesics; Benzophenones; Calculi; Cholelithiasis; Colic; Dipyrone; Drug Combinations; Humans; Kidney; Kidney Calculi; Muscle Relaxants, Central; Myocardial Infarction; Piperidines