piperidines and Tachycardia--Supraventricular

This article reviews experimental and clinical studies of a novel antiarrhythmic agent niferidile. Niferidile, a class III antiarrhythmic agent, blocks potassium outward currents, prolongs repolarization and refractory periods predominantly in atria than in ventricles. Intravenous Niferidile was efficient for interruption of AV-nodal and orthodromic re-entrant tachycardias with rates of 75% to 80%. Niferidile had a conversion rate of up to 87.3% in persistent atrial fibrillation and up to 100% in persistent atrial flutter. Proarrhythmic action of niferidil administration manifested as nonsustained torsade de pointes and monomorphic ventricular tachycardia in 1.2 and 3.7% of cases, respectively. Niferidile can be used for pharmacological cardioversion of persistent atrial fibrillation and flutter as an alternative to electrical cardioversion.

Topics: Animals; Anti-Arrhythmia Agents; Atrial Fibrillation; Dogs; Heart Atria; Humans; Myocytes, Cardiac; Piperidines; Potassium Channel Blockers; Rats; Tachycardia, Supraventricular

Intracardiac electrophysiological effects and antiarrhythmic activity of novel domestic class III antiarrhythmogenic drug niferidil has been studied in a group of 25 patients with paroxismal supraventricular tachycardia (PSVT) diagnosis. The drug was administered in a dose of 20 mg/kg (i.v.). Niferidil injections increased the refractory periods in both right and left atrium (by 22 and 20%, respectively, p < 0.001), right ventricle (12%, p < 0.01), and the His-Purkinje system (34%, p < 0.001) and improved additional anterograde and retrograde conduction (by 22 and 31%, respectively, p < 0.001), while not influencing the conduction via excitable cardiac tissues. Elongation of the QTc interval (22%, p <0.05) in one case was accompanied by an arrythmogenic effect (induction of short-term polymorphous ventricular tachycardia of the "torsade de pointes" type. Niferidil arrested PSVT in 78% cases and prevented PSVT development in response to endocardial stimulation in 86% of patients.

Topics: Adult; Aged; Anti-Arrhythmia Agents; Electrocardiography; Female; Heart; Humans; Male; Middle Aged; Piperidines; Refractory Period, Electrophysiological; Tachycardia, Paroxysmal; Tachycardia, Supraventricular

Remifentanil is commonly used during anesthesia in pediatric electrophysiologic studies (EPS). The purpose of this study is to determine the effects of remifentanil on the cardiac electrophysiologic properties of children undergoing ablation of supraventricular tachycardia (SVT). A prospective study was performed in patients undergoing EPS before ablation of SVT. Each patient received two different anesthetic protocols: protocol 1 = propofol (200 mcg/kg/min) and protocol 2 = propofol (120 mcg/kg/min) plus remifentanil (0.3 mcg/kg/min). EPS data were measured during the steady state of each protocol. Paired Student t test was performed for analysis of continuous data. All p values <0.05 were considered statistically significant. Fifteen patients were enrolled between April 2005 and January 2006. The mean age was 13.3 ± 2.9 years (range 6.7 to 17.7). Seven patients had atrioventricular (AV) nodal re-entry tachycardia; 5 patients had Wolff-Parkinson-White syndrome; 2 patients had a concealed accessory pathway; and 1 patient was not inducible. Of the 14 patients who underwent ablation, 13 (93%) achieved successful. The baseline sinus cycle length extended from 884 ± 141 ms during protocol 1 to 980 ± 165 ms during protocol 2 (p = 0.01), and the Wenckebach cycle length lengthened from 377 ± 96 ms to 406 ± 109 ms (p = 0.01). No other variables measured (atrial-His (AH) and His-ventricular (HV) interval, atrioventricular node (AVN), and atrial, ventricular, and accessory pathway effective refractory periods) changed significantly between the two different protocols. In pediatric patients undergoing EPS before ablation of SVT, remifentanil appears to slow both sinus and AV nodal function. These effects should be taken into consideration when performing EPS.

Topics: Adolescent; Anesthetics, Intravenous; Cardiac Electrophysiology; Catheter Ablation; Child; Female; Heart Conduction System; Humans; Male; Piperidines; Remifentanil; Tachycardia, Supraventricular

Atrial fibrillation and paroxysmal supraventricular tachycardia are common disorders of the heart rhythm for which antiarrhythmic drug therapy is commonly prescribed. The Atrial Fibrillation Investigation with Bidisomide (AFIB) study was a randomized, placebo-controlled clinical trial designed to accomplish three goals in a single protocol: (1) to determine the efficacy of the antiarrhythmic drug bidisomide in the treatment of these two arrhythmias; (2) to establish the appropriate dose range for bidisomide; and (3) to detect an adverse mortality effect of bidisomide if one were present in patients with atrial fibrillation.. In this clinical trial, 1227 patients with atrial fibrillation and 187 with paroxysmal supraventricular tachycardia were randomly assigned to bidisomide (200, 400, or 600 mg BID) or placebo; patient groups with each arrhythmia were analyzed separately. Symptomatic recurrences of atrial fibrillation and paroxysmal supraventricular tachycardia were documented with the use of transtelephonic ECG monitoring. The time to the first symptomatic arrhythmia recurrence was measured in each patient and compared among treatment groups. Among the atrial fibrillation patients, there was no significant difference in the time to first symptomatic recurrence between the placebo group and any of the three bidisomide treatment groups; the hazard ratios (placebo:treatment) were 1.19, 1.03, and 1.14 for bidisomide 200, 400, and 600 mg BID, respectively. Among paroxysmal supraventricular tachycardia patients, there was a similar lack of a significant treatment effect; the hazard ratios were 1.30, 1.93, and 1.59 for bidisomide 200, 400, and 600 mg BID, respectively. In the primary safety analysis of mortality, 3 of 493 patients taking placebo died, compared with 9 of 488 patients taking one of the two higher doses of bidisomide (P>.10).. Bidisomide in the doses tested did not have a clinically important antiarrhythmic effect. The AFIB study provided a novel clinical trial design to test antiarrhythmic drugs for both safety and efficacy.

Topics: Aged; Anti-Arrhythmia Agents; Atrial Fibrillation; Double-Blind Method; Electrocardiography; Humans; Middle Aged; Piperidines; Tachycardia, Supraventricular

To establish the clinical efficacy of a single oral dose of pirmenol, we evaluated electrophysiologic and hemodynamic effects simultaneously after drug administration, performing electrophysiologic testing in 20 patients with ECG-documented paroxysmal supraventricular tachycardia (PSVT) before and after a single oral 200-mg dose of pirmenol. Hemodynamic measurements were made with a Swan-Ganz catheter in the first 10 consecutive patients. In a different series of patients, we administered a single 200-mg oral dose of pirmenol to evaluate its acute termination effect in 7 patients with PSVT and 9 with paroxysmal atrial fibrillation. Pirmenol prolonged the refractory period of the retrograde conduction system in patients with or without an accessory pathway, and supraventricular tachycardia was no longer inducible at 60 min in 11 patients [8 of 11 with atrioventricular (AV) reentrant tachycardia and 3 of 5 with AV nodal reentrant tachycardia]. Pirmenol increased the heart rate (p < 0.01) and total systemic resistance (p < 0.05), and reduced the stroke volume index (p < 0.01), all significantly. The plasma concentration of pirmenol at 1 h after administration was 0.75 +/- 0.48 microgram/ml. A single oral dose of pirmenol during tachyarrhythmia successfully restored sinus rhythm in 4 of 7 (57%) patients with PSVT and 4 of 9 (44%) patients with paroxysmal atrial fibrillation. A single oral dose of pirmenol was well tolerated as episodic treatment in patients with supraventricular tachyarrhythmias.

Topics: Administration, Oral; Adult; Anti-Arrhythmia Agents; Atrial Fibrillation; Female; Hemodynamics; Humans; Male; Middle Aged; Piperidines; Tachycardia, Atrioventricular Nodal Reentry; Tachycardia, Supraventricular

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: Adult; Anesthesia, Intravenous; Anesthesia, Obstetrical; Anesthetics, Intravenous; Cardiomyopathies; Female; Humans; Infant, Newborn; Male; Piperidines; Pregnancy; Remifentanil; Tachycardia, Paroxysmal; Tachycardia, Supraventricular

Topics: Aged; Anesthetics, Intravenous; Cardiopulmonary Resuscitation; Electric Countershock; Electrocardiography; Humans; Male; Oxygen Inhalation Therapy; Piperidines; Remifentanil; Tachycardia, Supraventricular

Ebstein's anomaly is a rare congenital cardiac defect associated with both displacement and incompetence of the tricuspid valve. The condition is commonly complicated by supraventricular tachycardias. We describe the management of a patient with this condition undergoing caesarean section. Propofol and remifentanil total intravenous anaesthesia resulted in haemodynamic stability and delivery of a healthy baby who breathed spontaneously after two minutes.

Topics: Adult; Anesthesia, Intravenous; Anesthesia, Obstetrical; Anesthetics, Intravenous; Blood Pressure; Cesarean Section; Ebstein Anomaly; Electrocardiography; Female; Heart Rate; Humans; Intubation, Intratracheal; Monitoring, Physiologic; Piperidines; Pregnancy; Propofol; Rare Diseases; Remifentanil; Tachycardia, Supraventricular

The electrophysiologic effects of intravenous (i.v.) E-4031, a new class III antiarrhythmic drug, were evaluated in 15 patients with supraventricular tachyarrhythmias [11 men, 4 women; mean age 41 +/- 19 (SD) years]. Eleven patients had accessory atrioventricular (AV) pathways, and 4 patients with no accessory pathway had paroxysmal atrial fibrillation. Electrophysiologic studies were performed before and after E-4031 administration (loading infusion 9 micrograms/kg for 5 min + maintenance infusion 0.15 microgram/kg/min). QT and QTc intervals were significantly prolonged by E-4031 from 0.40 +/- 0.03 (mean +/- SD) to 0.46 +/- 0.03 s (p < 0.0001) and from 0.43 +/- 0.03 to 0.49 +/- 0.04 s (p < 0.0001), respectively. No effect was observed on RR interval, PR interval, QRS duration, or AH and HV intervals. The effective refractory periods (ERPs) of the right atrium and ventricle were significantly prolonged from 219 +/- 27 to 236 +/- 26 ms (p < 0.001) and from 230 +/- 12 to 249 +/- 11 ms (p < 0.001), respectively. The ERP of the AV node did not change significantly after E-4031 administration. In patients with ventricular preexcitation, E-4031 significantly prolonged the ERP of the antegrade accessory pathway conduction from 340 +/- 101 to 362 +/- 106 ms (p < 0.001), but not retrograde accessory pathway conduction. AV reentrant tachycardia was induced in 3 of 11 patients with an accessory pathway, and repetitive atrial firing was induced in 3 of 4 patients with paroxysmal atrial fibrillation. E-4031 could prevent repetitive atrial firing in only 1 patient and could not prevent induction of AV reentrant tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Anti-Arrhythmia Agents; Blood Pressure; Electrocardiography; Electrophysiology; Female; Heart Conduction System; Heart Rate; Humans; Injections, Intravenous; Male; Middle Aged; Piperidines; Pyridines; Refractory Period, Electrophysiological; Tachycardia, Supraventricular

Topics: Adult; Aged; Anti-Arrhythmia Agents; Electrocardiography; Female; Humans; Male; Middle Aged; Piperidines; Pyridines; Tachycardia, Supraventricular

The electrophysiologic effects of the intravenous administration of a new antiarrhythmic drug, lorcainide, were evaluated by programmed electrical stimulation of the heart in 20 patients with and without Wolff-Parkinson-White (WPW) syndromes. Lorcainide shortened the sinus cycle length from 721.0 +/- 125.9 to 649.5 +/- 100.1 ms (P less than 0.001), but did not influence sinus node function and AV node conduction and refractoriness, slightly increased atrial effective period (ERP) (P less than 0.02) and did not change ventricular ERP (P less than 0.2), obviously lengthened atrial conduction time, H, H-V interval and the width of V wave. Lorcainide caused complete antegrade block of the accessory pathway (AP) in six of 9 WPW patients and resulted in exclusive conduction over the AV nodal. His conduction in two patients with atrial flutter. It also prolonged the retrograde conduction time and refractoriness of AP, and prevented initiation of orthodromic atrioventricular tachycardia (O-AVRT) in six of 12 patients by blocking of the retrograde conduction of the AP, increased the cycle length of tachycardia from 321.7 +/- 43.6 to 361.7 +/- 54.9 ms (P less than 0.005) by marked prolongation of retrograde AP conduction time in 6 patients in whom O-AVRT could still be induced. It is concluded that intravenous lorcainide does not affect sinus node and AV node function, slightly influences atrial and ventricular refractoriness, obviously suppresses atrial, His bundle and intraventricular conduction, and is an effective antiarrhythmic drug for patients with WPW by blocking both the antegrade and retrograde conduction of the AP.

Topics: Adolescent; Adult; Anti-Arrhythmia Agents; Benzeneacetamides; Child; Electrophysiology; Female; Heart Conduction System; Humans; Male; Middle Aged; Piperidines; Tachycardia, Supraventricular; Wolff-Parkinson-White Syndrome

Lorcainide was used in 17 children and adolescents aged 14 days to 18 years (mean 6.8 years) with the preexcitation syndrome (W-P-W type). Lorcainide was able to control attacks of supraventricular tachycardia in eight of 11 patients with the W-P-W syndrome and tachyarrhythmias. Long-term maintenance therapy prevented new attacks of tachyarrhythmia for an average period of nine (5-15) months in all seven patients who tolerated lorcainide administration. Normalization of the W-P-W pattern was reached in nine of 11 children with the W-P-W syndrome who had tachyarrhythmias and in three of six asymptomatic children with the ECG pattern of W-P-W. Single effective doses ranged from 12.5 mg orally in the neonates to 100 mg in the adolescents. The effect of lorcainide on the ECG usually appeared 2 h after the oral administration of the drug. Dizziness in three with insomnia and vomiting in one patient complicated the treatment. No drug-associated abnormalities in blood cell counts and biochemical values were identified.

Topics: Adolescent; Anti-Arrhythmia Agents; Benzeneacetamides; Cardiac Complexes, Premature; Child; Child, Preschool; Electrocardiography; Female; Heart Conduction System; Humans; Infant; Infant, Newborn; Male; Piperidines; Tachycardia, Supraventricular; Wolff-Parkinson-White Syndrome

The effects of pirmenol in terminating paroxysmal supraventricular tachycardia were studied in 25 patients. Pirmenol was administered as 1 or 2 injections of 50 mg to 17 patients during a spontaneous attack, or as a 50-mg bolus followed by steady infusion of 2.5 mg/min in 8 patients during a tachycardia that was induced electrophysiologically. Termination was successful in 11 of 17 patients who had a spontaneous attack and in 3 of 8 patients who had induced tachycardia. Pirmenol was effective in 3 of 5 patients with atrioventricular nodal reentrant mechanism, but in none of 3 patients with a reentrant tachycardia with a retrogradely conducting atrioventricular bypass tract. Conversion to sinus rhythm was achieved in 14 of 25 patients (56%). No hemodynamic adverse effects occurred. Pirmenol increased the atrial effective refractory period, but had little effect on conduction in the atrioventricular node and His-Purkinje system. Reentry was abolished through a block in the retrograde part of the dual atrioventricular nodal pathway, which is typical of class I antiarrhythmic agents.

Topics: Adolescent; Adult; Aged; Anti-Arrhythmia Agents; Heart Conduction System; Humans; Middle Aged; Piperidines; Tachycardia, Supraventricular