benzofurans and Atrial-Fibrillation

Antiarrhythmic pharmaceutical development for the treatment of atrial fibrillation (AF) is moving in several directions. The efficacy of existing drugs, such as carvedilol, for rate control and, possibly, suppression of AF, is more appreciated. Efforts are being made to modify existing agents, such as amiodarone, in an attempt to ameliorate safety and adverse effect concerns. This has resulted in promising data from the deiodinated amiodarone analog, dronedarone, and further work with celivarone and ATI-2042. In an attempt to minimize ventricular proarrhythmia, atrial selective drugs, such as intravenous vernakalant, have demonstrated efficacy in terminating AF in addition to promising data in suppression recurrences when used orally. Several other atrial selective drugs are being developed by multiple manufacturers. Other novel therapeutic mechanisms, such as drugs that enhance GAP junction conduction, are being developed to achieve more effective drug therapy than is offered by existing compounds. Finally, nonantiarrhythmic drugs, such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, high-mobility group coenzyme A enzyme inhibitors and omega-3 fatty acids/fish oil, appear to have a role in suppressing AF in certain patient subtypes. Future studies will clarify the role of these drugs in treating AF.

Topics: Adenosine; Adenosine A1 Receptor Antagonists; Adrenergic beta-Antagonists; Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Biphenyl Compounds; Bridged Bicyclo Compounds, Heterocyclic; Carbazoles; Carvedilol; Cyclopropanes; Dronedarone; Fatty Acids, Omega-3; Furans; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Oligopeptides; Organic Chemicals; Peptidyl-Dipeptidase A; Potassium Channel Blockers; Propanolamines; Purinergic P1 Receptor Agonists

The value of programmed electrical stimulation (PES) and Holter monitoring in the assessment of amiodarone efficacy was reviewed. Many physicians have been disturbed by the persistent inducibility of arrhythmias in patients treated with amiodarone, who nevertheless do very well during the follow-up period. Noninducibility was associated with a favorable prognosis among 366 VT patients. Eighty-eight (24%) were noninducible on amiodarone, and 10% of these had recurrences, vs 39% in patients who remained inducible. Further, increased difficulty of induction with PES or induction of a slower or better tolerated VT may indicate a favorable outlook, and add to the value of PES. Few papers rigorously employed Holter monitoring in the assessment of amiodarone. In general, suppression of previously frequent arrhythmias implies excellent protection for patients with benign arrhythmias and moderate protection with malignant arrhythmias. By Holter assessment in 186 VT patients, arrhythmias were suppressed in 114 (61%), and 18% of these had recurrences vs 50% in patients whose arrhythmias were not suppressed. Studies attempting to correlate the results of PES and Holter monitoring in the same patients are lacking and may prove useful.

Topics: Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiac Pacing, Artificial; Clinical Trials as Topic; Electrocardiography; Electrophysiology; Female; Follow-Up Studies; Heart Conduction System; Humans; Male; Middle Aged; Monitoring, Physiologic; Pre-Excitation Syndromes; Prognosis; Tachycardia

Amiodarone, an investigational drug in the United States, has had considerable use in this country and worldwide in the treatment of cardiac arrhythmias. This article reviews the clinical pharmacology of this potentially useful antiarrhythmic agent.

Topics: Amiodarone; Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Autonomic Nervous System; Benzofurans; Bradycardia; Drug Interactions; Eye; Heart Conduction System; Heart Ventricles; Hemodynamics; Humans; Injections, Intravenous; Kinetics; Liver; Lung; Skin; Tachycardia; Thyroid Gland

Topics: Adolescent; Adrenergic beta-Antagonists; Adult; Aged; Ajmaline; Amiodarone; Anilides; Aprindine; Atrial Fibrillation; Benzofurans; Digitalis Glycosides; Disopyramide; Encainide; Female; Humans; Lidocaine; Male; Middle Aged; Procainamide; Quinidine; Tachycardia; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Female; Humans; Male; Middle Aged

Topics: Acute Disease; Administration, Oral; Amiodarone; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiovascular System; Dose-Response Relationship, Drug; Electrophysiology; Eye Manifestations; Heart Block; Humans; Injections, Intravenous; Muscle, Smooth, Vascular; Myocardial Infarction; Skin Manifestations; Tachycardia; Thyroid Gland; Wolff-Parkinson-White Syndrome

Celivarone, a new noniodinated benzofuran derivative pharmacologically related to dronedarone and amiodarone, has been shown to have antiarrhythmic properties at a molecular level. The purpose of the 2 trials presented here (MAIA and CORYFEE) was to assess celivarone efficacy in the maintenance of sinus rhythm postcardioversion and for the conversion of atrial fibrillation (AF)/atrial flutter (AFL).. In the MAIA trial, 673 patients with AF/AFL recently converted to sinus rhythm were randomly assigned to receive 50, 100, 200, or 300 mg once-daily dosing of celivarone; 200 mg daily of amiodarone preceded by a loading dose of 600 mg for 10 days; or placebo. At 3 months' follow up, no significant difference was observed in time to AF/AFL relapse among the various celivarone groups and placebo. However, fewer symptomatic AF/AFL recurrences were observed in the lower-dose celivarone groups (26.6% for celivarone 50 mg [P = 0.022] and 25.2% for celivarone 100 mg [P = 0.018] vs 40.5% for placebo at 90 days). Fewer adverse events were observed with the use of celivarone and placebo than amiodarone. In the CORYFEE study, 150 patients with AF/AFL were randomly assigned to once-daily celivarone dosing of 300 or 600 mg, or placebo, for a 2-day treatment period. There was no significant difference in the rate of spontaneous conversion to sinus rhythm between the treatment and control groups.. In these studies, celivarone does not appear to be efficacious in the maintenance of sinus rhythm in AF/AFL patients or for the conversion of AF/AFL patients. 

Topics: Aged; Anti-Arrhythmia Agents; Atrial Fibrillation; Atrial Flutter; Benzofurans; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Electrocardiography; Female; Heart Conduction System; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Predictive Value of Tests; Proportional Hazards Models; Recurrence; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome

ATI-2042 (budiodarone) is a chemical analogue of amiodarone with a half life of 7 h. It is electrophysiologically similar to amiodarone, but may not have metabolic and interaction side effects. The sophisticated electrocardiograph logs of advanced DDDRP pacemakers were used to monitor the efficacy of ATI-2042. The aim of this study was to determine the preliminary efficacy and safety of ATI-2042 in patients with paroxsymal atrial fibrillation (PAF) and pacemakers.. Six women with AF burden (AFB) between 1 and 50% underwent six sequential 2-week study periods. Patients received 200 mg bid of ATI-2042 during Period 2 (p2), 400 mg bid during p3, 600 mg bid during p4, 800 mg bid during p5, and no drug during baseline and washout (p1 and p6). Pacemaker data for the primary outcome measure AFB were downloaded during each period. Mean AFB decreased between baseline and all doses: AFB at baseline (SD) was 20.3 +/- 14.6% and mean AFB at 200 mg bid was 5.2 +/- 4.2%, at 400 mg bid 5.2 +/- 5.2%, at 600 mg bid 2.8 +/- 3.4%, and at 800 mg bid 1.5 +/- 0.5%. The mean reductions in AFB at all doses of ATI-2042 were statistically significant (P < 0.005). Atrial fibrillation burden increased in washout. Atrial fibrillation episodes tended to increase with ATI-2042, but this was offset by substantial decreases in episode duration. ATI-2042 was generally well tolerated.. ATI-2042 effectively reduced AFB over all doses studied by reducing mean episode duration. A large-scale study will be required to confirm this effect.

Topics: Aged; Aged, 80 and over; Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Combined Modality Therapy; Dose-Response Relationship, Drug; Electrocardiography; Female; Humans; Middle Aged; Pacemaker, Artificial; Prospective Studies; Treatment Outcome

The value of programmed electrical stimulation (PES) and Holter monitoring in the assessment of amiodarone efficacy was reviewed. Many physicians have been disturbed by the persistent inducibility of arrhythmias in patients treated with amiodarone, who nevertheless do very well during the follow-up period. Noninducibility was associated with a favorable prognosis among 366 VT patients. Eighty-eight (24%) were noninducible on amiodarone, and 10% of these had recurrences, vs 39% in patients who remained inducible. Further, increased difficulty of induction with PES or induction of a slower or better tolerated VT may indicate a favorable outlook, and add to the value of PES. Few papers rigorously employed Holter monitoring in the assessment of amiodarone. In general, suppression of previously frequent arrhythmias implies excellent protection for patients with benign arrhythmias and moderate protection with malignant arrhythmias. By Holter assessment in 186 VT patients, arrhythmias were suppressed in 114 (61%), and 18% of these had recurrences vs 50% in patients whose arrhythmias were not suppressed. Studies attempting to correlate the results of PES and Holter monitoring in the same patients are lacking and may prove useful.

Topics: Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiac Pacing, Artificial; Clinical Trials as Topic; Electrocardiography; Electrophysiology; Female; Follow-Up Studies; Heart Conduction System; Humans; Male; Middle Aged; Monitoring, Physiologic; Pre-Excitation Syndromes; Prognosis; Tachycardia

Topics: Adrenergic beta-Antagonists; Aged; Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Cardiac Complexes, Premature; Clinical Trials as Topic; Female; Humans; Male; Middle Aged; Tachycardia, Paroxysmal; Time Factors

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Digoxin; Humans; Myocardial Infarction

Topics: Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Disopyramide; Female; Humans; Male; Random Allocation

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Clinical Trials as Topic; Coronary Disease; Female; Gastrointestinal Diseases; Heart Atria; Heart Conduction System; Humans; Male; Middle Aged; Mitral Valve Insufficiency; Quinidine; Random Allocation; Risk; Triiodothyronine

Forty patients with organic cardiopathies and permanent atrial fibrillation were divided at random into two similar groups in relation to their diagnoses and ages. Twenty patients were treated with digoxine alone, and the other 20 with digoxine plus amiodarone hydrochloride. Comparison of results from each group showed statistical significant differences (p less than 0.0005) regarding total digoxine dosage and length of treatment. Mechanism of action of this synergia is discussed, and the association of digitalis and amiodarone is recommended to reduce digitalization time in patients with paroxysmal auricular tachycardia.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digitalis Glycosides; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Time Factors

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Drug Evaluation; Electric Countershock; Female; Heart Conduction System; Humans; Male; Quinidine

Topics: Adult; Aged; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Clinical Trials as Topic; Evaluation Studies as Topic; Female; Humans; Male; Middle Aged; Tachycardia

The combination of antiarrhythmic agents, amiodarone or dronedarone, with the anticoagulant rivaroxaban is used clinically in the management of atrial fibrillation for rhythm control and secondary stroke prevention respectively. Renal drug-drug interactions (DDIs) between amiodarone or dronedarone and rivaroxaban were previously ascribed to inhibition of rivaroxaban secretion by P-glycoprotein at the apical membrane of renal proximal tubular epithelial cells. Benzbromarone, a known inhibitor of organic anion transporter 3 (OAT3), shares a benzofuran scaffold with amiodarone and dronedarone. However, inhibitory activity of amiodarone and dronedarone against OAT3 remains arcane. Here, we conducted in vitro transporter inhibition assays in OAT3-transfected HEK293 cells which revealed amiodarone, dronedarone and their respective major pharmacologically-active metabolites N-desethylamiodarone and N-desbutyldronedarone possess inhibitory activity against OAT3, with corrected K

Topics: Amiodarone; Anti-Arrhythmia Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Atrial Fibrillation; Benzofurans; Cell Line; Dronedarone; Drug Interactions; HEK293 Cells; Humans; Organic Anion Transporters, Sodium-Independent; Rivaroxaban

Topics: Aged; Atrial Fibrillation; Benzofurans; Catheter Ablation; Cryosurgery; Female; Gastroparesis; Humans; Postoperative Complications; Serotonin 5-HT4 Receptor Agonists; Severity of Illness Index; Tomography, X-Ray Computed

Topics: Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Combined Modality Therapy; Dose-Response Relationship, Drug; Dronedarone; Humans; Pacemaker, Artificial; Phenethylamines; Sulfonamides

SSR149744C (2-butyl-3-{4-[3-(dibutylamino)propyl]benzoyl}-1-benzofuran-5-carboxylate isopropyl fumarate) is a new noniodinated benzofuran derivative structurally related to amiodarone and dronedarone that is currently undergoing clinical trials as an antiarrhythmic agent. As SSR149744C exhibits electrophysiological and hemodynamic properties of class I, II, III, and IV antiarrhythmic agents, the aim of this study was to evaluate its acute intravenous (IV) or oral (PO) antiarrhythmic activities in in vitro and in vivo animal models of atrial and ventricular arrhythmias. In vagally induced atrial fibrillation (AF) in anesthetized dogs, SSR149744C (3 and 10 mg/kg IV) terminated AF in all 7 dogs and prevented reinduction in 4 out of 7 dogs; effective refractory periods of right atrium were dose-dependently and frequency-independently lengthened. In low-K+ medium-induced AF models, SSR149744C (0.1 to 1 microM) prevented AF in isolated guinea pig hearts in a concentration-dependent manner. At the ventricular level, SSR149744C (0.1 to 10 mg/kg IV and 3 to 90 mg/kg PO) prevented reperfusion-induced arrhythmias in anesthetized rats with a dose-effect relationship, and, at doses of 30 to 90 mg/kg PO, it reduced early (0-24 hours) mortality following permanent left coronary artery ligature in conscious rats. The present results show that SSR149744C is an effective antiarrhythmic agent in atrial fibrillation and in ventricular arrhythmias. Like amiodarone and dronedarone, its efficiency in these animal models of arrhythmias is likely be related to its multifactorial mechanism of action.

Topics: Administration, Oral; Animals; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Death, Sudden, Cardiac; Dogs; Electric Stimulation; Female; Guinea Pigs; In Vitro Techniques; Injections, Intravenous; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Potassium; Rats; Rats, Sprague-Dawley; Vagus Nerve; Ventricular Dysfunction

Vagus-induced atrial fibrillation is of particular clinical interest. The muscarinic potassium current I(K(ACh)) mediates the induction of vagus-induced atrial fibrillation. Selective inhibition of I(K(ACh)) seems to be an option to treat atrial fibrillation. The application of amiodarone, presently one of the most important antiarrhythmic agents in the parmacological treatment of atrial fibrillation, is limited by its adverse effects. KB130015, a new amiodarone derivative, and ibutilide are new class III antiarrhythmic agents.. In guinea-pig atrial myocytes the muscarinic potassium current (I(K(ACh))) was activated by acetylcholine and adenosine. The effect of KB130015 on I(K(ACh)) was measured using the whole-cell voltage-clamp method.. KB130015 and ibutilide in a concentration of 50 microM effectively inhibited the muscarinic potassium current. The effect was concentrationdependent and reversible. The half-maximum effective concentration was 0.8 microM (KB130015) and 2.8 microM (ibutilide). The inhibition of I(K(ACh)) was independent of the mode of its activation. The adenosine-induced ion current was as well inhibited by both drugs as the acetylcholine-induced ion current. Via GTP-gamma-S irreversibly activated I(K(ACh)) was also inhibited by KB130015 and ibutilide, whereas intracellular application showed no effect on I(K(ACh)).. KB130015 and ibutilide are potent inhibitors of IK(ACh). Their effect is most likely mediated by direct interaction with the extracellular part of the ion channel. Acute effects of KB130015 on ventricular myocardium are not known so far. Ibutilide on the other hand is known to inhibit I(kr). KB130015 is a promising antiarrhythmic agent for the pharmacotherapy of vagus-induced atrial fibrillation.

Topics: Animals; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Cells, Cultured; Guinea Pigs; Heart Atria; Potassium Channels; Receptors, Muscarinic; Sulfonamides

Repetitive supraventricular tachycardia is an uncommon arrhythmia which usually occurs in patients free of structural heart disease. It is characterized by incessant short salvos of supraventricular tachycardia separated by only one or two normal sinus beats. Therapy with conventional antiarrhythmic drugs is usually ineffective. This report describes three patients with repetitive supraventricular tachycardia in whom evidence for associated sinus node dysfunction was observed. Amiodarone therapy, with ventricular pacing in two patients, has provided effective control of this arrhythmia in all three patients.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Dose-Response Relationship, Drug; Electrocardiography; Heart Atria; Humans; Male; Middle Aged; Tachycardia, Paroxysmal

Amiodarone was used in the treatment of 21 patients with supraventricular or ventricular arrhythmias which were refractory to conventional antiarrhythmic drugs, individually or in combination. Six of seven patients with supraventricular arrhythmias and 12 of 14 with ventricular tachycardia were controlled with amiodarone. Although side effects were common, only one patient was removed from treatment due to pulmonary fibrosis. We conclude that amiodarone is an effective antiarrhythmic drug for refractory ventricular and supraventricular arrhythmias.

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Cardiac Complexes, Premature; Cardiomyopathy, Dilated; Coronary Disease; Coronary Vasospasm; Dose-Response Relationship, Drug; Heart Aneurysm; Heart Atria; Heart Ventricles; Humans; Recurrence; Tachycardia

Topics: Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Humans

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Female; Heart; Humans; Male; Middle Aged; Quinidine

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digoxin; Female; Humans; Male

Five cases of amiodarone-induced syncope due to torsades de pointes or ventricular fibrillation are described. Amiodarone was used for recurrent supraventricular tachycardia in four cases and frequent ventricular extra systoles complicating congenital QT prolongation in the remaining case. Each was associated with a marked prolongation in the QTc interval following amiodarone. Three cases had had a previous history of life-threatening ventricular arrhythmias secondary to anti-arrhythmic drugs. Hypokalemia may have been a contributory factor in two. The clinical features, predisposing factors, and treatment are discussed.

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Drug Therapy, Combination; Electrocardiography; Female; Heart Arrest; Heart Failure; Humans; Long QT Syndrome; Tachycardia

Atrial fibrillation (AF) is a difficult arrhythmia to manage with antiarrhythmic agents. Amiodarone is highly effective in restoring and maintaining normal sinus rhythm in patients with AF. However, the mechanism and predictors of efficacy for amiodarone in treating AF have not been adequately addressed. Various measures of success or failure of amiodarone therapy were examined in 68 patients who had paroxysmal or chronic, established AF refractory to conventional antiarrhythmic agents. The patients were 25 to 75 years old (mean 59) and mean follow-up was 21 months (range 3 to 56). Maintenance amiodarone dosages were 200 to 400 mg/day. Overall, amiodarone therapy was effective long term in 54 of the 68 patients (79%). Left atrial diameter, age, gender and origin of AF were not helpful in predicting success or failure of amiodarone therapy. The presence of chronic AF for longer than 1 year was an adverse factor in maintaining normal sinus rhythm (p = 0.007), although the success rate even in this group was relatively high (57%). Thirty-five percent of the patients had adverse effects, which precluded long-term therapy with amiodarone in 10%.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Chronic Disease; Drug Evaluation; Female; Follow-Up Studies; Humans; Male; Middle Aged

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digoxin; Drug Resistance; Female; Heart Rate; Humans; Male; Middle Aged

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Female; Heart; Humans; Male; Middle Aged; Refractory Period, Electrophysiological; Tachycardia; Wolff-Parkinson-White Syndrome

In 65 patients a single oral dose of amiodarone (30 mg/kg) produced an antiarrhythmic effect on supraventricular or ventricular arrhythmias within 3 to 8 hours and lasted for 17 to 19 hours. On the second day a 15-mg/kg dose reproduced this effect within 3 to 9 hours. Plasma concentration of amiodarone increased to a maximum (2.2 +/- 1.7 mg/liter) mean +/- standard deviation) at 6 +/- 3.5 hours and plasma levels of N-desethylamiodarone (NDA) rose to 0.2 +/- 0.08 mg/liter at 12 +/- 6.4 hours. Sixty-one other patients were given a single 30-mg/kg dose 7 hours to 4 days before open heart surgery. Biopsies of the right atrial and left ventricular walls were taken during surgery. Myocardial concentration of amiodarone was maximal in the atrium after 7 hours (13 +/- 8 mg/kg) and in the ventricle after 24 hours (17 +/- 11 mg/kg). NDA myocardial concentration increased progressively until 24 hours and then remained stable over 4 days (1.5 mg/kg). The amiodarone myocardial to plasma concentration ratio was similar in the atrium and in the ventricle and averaged 22 and 10 for amiodarone and NDA, respectively. A significant relation existed between amiodarone concentration and the effect on ventricular premature complexes (r = 0.74, p less than 0.001) and between amiodarone plasma concentration and the effect on the atrioventricular conduction (r = 0.58, p less than 0.001). The plasma concentration of amiodarone corresponding to a 60% decrease in arrhythmias averaged 1.5 to 2 mg/liter.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Administration, Oral; Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrioventricular Node; Benzofurans; Dose-Response Relationship, Drug; Electrocardiography; Female; Heart Atria; Humans; Male; Middle Aged; Myocardium; Tachycardia; Time Factors

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digoxin; Drug Resistance; Female; Heart Rate; Humans; Male; Middle Aged

This study was performed to ascertain whether intravenous amiodarone would revert supraventricular tachycardias to sinus rhythm, and if so, whether this effect depended upon the underlying mechanism of the arrhythmia. Fourteen patients were studied. Seven had Wolff-Parkinson-White (WPW) syndrome, 1 had dual atrioventricular nodal pathways and 1 an ectopic atrial tachycardia. Five patients had atrial fibrillation without accessory pathways. An atrial electrode was inserted to initiate tachycardias and record the electrogram. If tachycardias were stable for more than 5 min, amiodarone (5 mg/kg) diluted with dextrose saline was infused intravenously over 5 min. Two electrocardiographic leads and the right atrial electrogram were monitored. In 7 patients with atrial fibrillation (2 with accessory pathways), 6 did not revert to sinus rhythm, 1 reverted only after 1 hr. In 5 cases without accessory pathways the ventricular rate fell 5-10 min after commencing amiodarone. Four of the 5 patients with WPW syndrome and re-entrant tachycardias returned to sinus rhythm within 6 min of commencing the infusion (atrioventricular and ventriculoatrial times increased by 0-38% and 0-14% respectively). (Tachycardias terminated in the anterograde limb.) Three patients underwent intermittent right atrial stimulation for 1 hr. No tachycardias could be initiated for 30 min post amiodarone. The ectopic atrial tachycardia and that due to dual atrioventricular nodal pathways terminated within 7 and 2 min, respectively, of commencing intravenous amiodarone. Thus the use of intravenous amiodarone would be appropriate in the acute management of sustained supraventricular tachycardias.

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Atrioventricular Node; Benzofurans; Cardiac Pacing, Artificial; Electrocardiography; Female; Heart Ventricles; Humans; Injections, Intravenous; Male; Middle Aged; Tachycardia; Wolff-Parkinson-White Syndrome

A patient with sinuatrial disease and implanted pacemaker was treated with amiodarone (maximum dose 1000 mg, maintenance dose 800 mg daily) for 10 months, for control of supraventricular tachyarrhythmias. He developed pneumonitis, pleural and pericardial effusions, and a predominantly proximal motor neuropathy. Immediate but gradual improvement followed withdrawal of amiodarone and treatment with prednisolone. Review of this and previously reported cases indicates the need for early diagnosis of amiodarone pneumonitis, immediate withdrawal of amiodarone, and prompt but continued steroid therapy to ensure full recovery.

Topics: Adult; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Combined Modality Therapy; Exercise Test; Humans; Male; Motor Neurons; Neural Conduction; Neuromuscular Diseases; Pacemaker, Artificial; Pericardial Effusion; Pleural Effusion; Pneumonia, Aspiration; Pneumonia, Lipid; Tachycardia

We report two patients who developed symptomatic life-threatening ventricular tachyarrhythmias with changing QRS axes (resembling torsades de pointes), during treatment of their supraventricular tachycardias with oral amiodarone. Like other effects of amiodarone on the body, the arrhythmias became evident several days after initiating therapy, at which time electrocardiographic QT prolongation was present. The arrhythmias subsided after amiodarone treatment was withdrawn. No other drugs or electrolyte disturbances could be incriminated as a cause.

Topics: Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Digoxin; Electrocardiography; Female; Humans; Tachycardia

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Female; Fetal Blood; Humans; Pregnancy; Pregnancy Trimester, Second; Wolff-Parkinson-White Syndrome

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Humans; Male; Stevens-Johnson Syndrome

The Authors evaluated the effectiveness and the tolerance of intravenous Amiodarone in 50 cases of recent onset paroxysmal supraventricular tachyarrhythmias. Fifty consecutive patients, aged 17 to 84 (mean 52 years), presenting with paroxysmal supraventricular tachycardia (PSVT, 33 cases) or atrial flutter (11 cases) or atrial fibrillation (6 cases), were given 300 mg of Amiodarone intravenously within 2 min, followed in 4 patients by 150 mg after 15 min. All patients were monitored for 1 hour; ECG and blood pressure were recorded at fixed times. Within 15 min sinus rhythm was restored in 88% of PSVT, in 27% of atrial flutter and in 17% of atrial fibrillation cases; the other cases of atrial flutter and fibrillation always showed a 48-81% reduction of the average heart rate within 15 min. We have evidenced neither significant modifications of blood pressure and ECG parameters (P-Q, QRS and Q-T duration) nor particular side effects, except for 2 cases in which brief hot flushes were reported. The Authors believe Amiodarone to be an effective and well tolerated drug for the above mentioned arrhythmias, particularly promptly acting in PSVT cases, in whom sinus rhythm was restored within 15 min in 88% and within 1 hour in 100% of the cases.

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Female; Humans; Injections, Intravenous; Male; Middle Aged; Tachycardia, Paroxysmal

We tested the efficacy of intravenous amiodarone (5 mg/kg) in slowing ventricular response and/or restoring sinus rhythm in 26 patients with paroxysmal or new atrial fibrillation with fast ventricular response. There were 16 men and 10 women with ages ranging from 35 to 84 years, mean 63 years. Intravenous amiodarone initially slowed the ventricular response in all patients from 143 +/- 27 to 96 +/- 10 beats/min (P less than 0.001). Twelve patients (46%) reverted to sinus rhythm within the first 30 min (range 5 to 30 min, mean 14 +/- 9 min). One patient reverted to atrial flutter after 10 min and 40 min later to sinus rhythm. Six patients (23%) converted to sinus rhythm after 2 to 8 hr and in these 6 cases, the initial slowing in ventricular response obtained with amiodarone persisted until conversion. Seven patients (27%) did not convert to sinus rhythm following amiodarone administration and they required further medical therapy to slow the ventricular response and/or to convert to sinus rhythm. No serious side effects from drug administration were noted. Intravenous amiodarone appears as a highly effective medication in the conversion or control of new onset atrial fibrillation with fast ventricular response.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Atrioventricular Node; Benzofurans; Electrocardiography; Female; Heart Rate; Heart Ventricles; Humans; Infusions, Parenteral; Male; Middle Aged; Recurrence

The efficacy of amiodarone was assessed in 38 patients with atrial fibrillation resistant to quinidine and an effort made to identify factors correlated with amiodarone response. The study group included 29 patients with and 9 without organic heart disease and either persistent (n = 11) or paroxysmal (n = 27) atrial fibrillation. All patients were treated with amiodarone and followed up in a research clinic. Efficacy was classified as excellent (no recurrent symptomatic atrial fibrillation) in 15 (55%) of 27 patients with paroxysmal and 5 (45%) of 11 patients with persistent atrial fibrillation. Efficacy was poor (no effect on atrial fibrillation) in 5 (19%) of 27 patients with paroxysmal and 6 (55%) of 11 patients with persistent atrial fibrillation. Efficacy was good (amelioration but not total suppression) in 7 (26%) of 27 patients with paroxysmal atrial fibrillation. Efficacy was related to echocardiographic left atrial dimension, left ventricular ejection fraction and, in patients with persistent atrial fibrillation, the duration of the arrhythmia. During the follow-up period of 15 months (range 1 to 36), overall efficacy (considering response and toxicity) was 67% in the 27 patients with paroxysmal and 45% in the 11 patients with persistent atrial fibrillation. It is concluded that amiodarone offers an additional therapeutic alternative in quinidine-resistant atrial fibrillation and that certain clinical factors are correlated with amiodarone response.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Drug Resistance; Female; Humans; Male; Middle Aged; Quinidine

Topics: Adult; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Electric Countershock; Female; Follow-Up Studies; Humans; Male; Middle Aged; Premedication

Sudden death in Wolff-Parkinson-White syndrome (WPW) is related to a very fast ventricular response to spontaneous atrial fibrillation (AF) conducted via accessory pathway (AP). The effect of oral amiodarone was studied in 12 patients with WPW syndrome and life-threatening rapid ventricular response via an AP during spontaneous AF. The effective refractory period of the AP in the anterograde direction was 280 ms or less during control study in all patients. After amiodarone therapy, the effective refractory period remained 280 ms or less in 7 of the 12 patients. During incremental atrial pacing, the longest atrial pacing cycle length that produced block over an AP ranged from 200 to 310 ms (mean 261 +/- 42) during the control period and 240 to 980 ms (mean 377 +/- 198) after amiodarone therapy. During AF the shortest ventricular response via the AP could be measured in 10 of 12 of the patients both before and after amiodarone treatment and ranged from 200 to 290 ms (234 +/- 30) and 250 to 500 (mean 302 +/- 75), respectively (p less than 0.01). The average RR interval during AF before and after the drug ranged from 200 to 390 ms (mean 280 +/- 55) and 280 to 650 ms (mean 396 +/- 116), respectively (p less than 0.01). Thus, the safety of amiodarone in the WPW syndrome should be established by electrophysiologic studies and induction of AF, because amiodarone is not protective in all patients with WPW.

Topics: Adolescent; Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Cardiac Pacing, Artificial; Electrocardiography; Female; Heart Conduction System; Humans; Male; Middle Aged; Prospective Studies; Tachycardia; Wolff-Parkinson-White Syndrome

Amiodarone, a widely used iodine-containing antiarrhythmic drug, has been shown to divert the peripheral metabolism of T4 towards rT3 than T3. In this prospective study we correlated the concentration of the peripheral thyroid hormones in serum with that of amiodarone. Fifteen euthyroid volunteers were studied, 5 men and 10 women, with a mean age of 64.2 yr, who suffered from various cardiac arrhythmias (atrial fibrillation or multiple ventricular extrasystoles). Serum amiodarone, T4, T3, rT3 and TSH were determined before and 3, 7, and 14 days after the administration of 400-600 mg amiodarone/day. There was a small increase in serum T4 and a suggestive decrease in serum T3. The increase in serum rT3 was significant, with p less than 0.05 for 3 days, p less than 0.01 for 7 days and p less than 0.005 for 14 days. There was a significant correlation between the level of serum amiodarone and the rise in serum rT3 (r = 0.385, p less than 0.05). The rise in rT3 is the main thyroid abnormality after amiodarone administration and may be used as a rough index of the serum concentration of this drug.

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Female; Humans; Male; Middle Aged; Thyrotropin; Thyroxine; Triiodothyronine; Triiodothyronine, Reverse; Ventricular Fibrillation

In a 61-year-old man receiving chronic low-dosage amiodarone an interstitial pneumopathy was observed. In the absence of other causes, we suspected an adverse reaction to amiodarone, not least because of the similarity with histologic findings of cases previously reported. Drug withdrawal and cortisone administration led to resolution of the disease.

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Biopsy; Humans; Lung; Male; Middle Aged; Pulmonary Fibrosis; Time Factors

Twenty-seven patients with atrial fibrillation without any concomitant conduction abnormality have been treated with oral amiodarone in a daily maintenance dose of 200 mg. The drug has been used for three purposes: 1) to block atrioventricular conduction, thereby decreasing the ventricular rate during atrial fibrillation (9 patients), 2) as prophylaxis against paroxysmal atrial fibrillation (8 patients), 3) as prophylaxis against recurrence of atrial fibrillation after DC conversion to sinus rhythm (13 patients). All patients were considered refractory to other antiarrhythmic drugs in these respects. In the second group, 4 of the 8 patients reported complete cessation of attacks and the others a marked reduction of the attack rate. In the third group, 10 of the 13 patients have maintained sinus rhythm for a longer period on treatment with amiodarone than with other drugs, resulting more than a triple prolongation of the time in sinus rhythm. In 3 patients the drug has been discontinued because of side-effects. In conclusion, amiodarone affords protection from episodes of paroxysmal atrial fibrillation, as well as from recurrence of atrial fibrillation after DC conversion to sinus rhythm. If the drug is ineffective in either of these respects, it may still be useful as a means of moderating the ventricular response in atrial fibrillation.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrioventricular Node; Benzofurans; Electric Countershock; Female; Heart Rate; Humans; Male; Middle Aged

Fifty-three patients with hypertrophic cardiomyopathy who had serious arrhythmias (45 patients), refractory chest pain (5 patients) or a high risk of sudden death (3 patients) received amiodarone for 6 to 96 months (median 18) after completion of a loading and an initial maintenance period. The dose of amiodarone was altered by 50 to 200 mg/day at 3- to 6-month intervals, guided by electrocardiographic monitoring, plasma drug level measurements and side-effect questionnaires. Ventricular tachycardia was suppressed in 24 patients (92%) with doses of 100 to 400 mg/day (median 300); none died suddenly during a mean follow-up of 27 months. Although symptomatic episodes of frequent or prolonged supraventricular tachycardia or paroxysmal atrial fibrillation/flutter were abolished in 8 of 9 patients on 100 to 600 mg/day (median 300), in 1 patient incessant atrial flutter developed that was relatively refractory to direct-current cardioversion. In 11 patients with atrial fibrillation, sinus rhythm was restored in 7 (after direct-current cardioversion in 3) with doses of 100 to 600 mg/day (median 300) and has been maintained in 5 with associated improvement in symptoms. Despite discontinuation of beta-blocker therapy, chest pain was unchanged in 17 patients, was impaired in 11 and was worse in only 2. Amiodarone was discontinued in 3 patients; in 1 because of hair loss, in 1 because of neurologic symptoms and in 1 because of facial discoloration; in the latter 2 patients, amiodarone was restarted after 1 and 14 months, and was tolerated and effective at the lower dosage.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiomyopathy, Hypertrophic; Echocardiography; Electrocardiography; Heart Rate; Humans; Middle Aged; Pain; Thorax

Forty patients with atrial fibrillation (AF), 23 patients with ventricular extrasystoles (VES), and 11 patients with various arrhythmias (VA) were treated with amiodarone (0.2-0.6 g/day). Suppression of arrhythmia was 67.5% in AF, 78.2% in VES, and 81.8% in others with VA. Median age of converted patients was higher than that of nonconverted. The duration of AF before treatment was inversely related to drug efficacy. Average time needed for conversion was 6-8 days of treatment. Plasma amiodarone concentration at the day of conversion did not differ from that of nonconverted patients. Amiodarone concentration levels off after the 8th day of treatment, whereas that of the metabolite increases with time of treatment. Biologic half-life of plasma amiodarone after discontinuation of treatment varied, but was higher than 4 days. The percent of decline of the metabolite concentration was lower than that of the parent drug.

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Electrocardiography; Female; Half-Life; Humans; Kinetics; Male; Middle Aged; Time Factors

Topics: Age Factors; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Cardiac Complexes, Premature; Hemodynamics; Humans; Middle Aged

Our use of amiodarone in 200 patients during an 8-year period confirms our previous experience which indicated that the drug was close to being the ideal antiarrhythmic agent in children's arrhythmias. Its absence of cardiac toxicity, its powerful antiarrhythmic properties, its depressive effect on the AV nodal conduction, combined with its beta-inhibitory effect makes it effective and harmless in practically all forms of atrial, junctional and ventricular arrhythmias, whatever the reentrant or automatic mechanism of the arrhythmia. The metabolism is much faster in children than in adults, making the drug active in a few hours, with a lesser prolonged duration of action. Though there is practically no limitation for its use on a short- or mean-term basis, the long-term use must be limited to truly refractory arrhythmias, a situation which is rarely encountered. In such cases, combining amiodarone with conventional therapy allows a decrease in the maintenance dosage and a lower incidence of extracardiac side effects.

Topics: Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Bundle-Branch Block; Child; Electrocardiography; Heart Conduction System; Heart Defects, Congenital; Heart Valve Diseases; Heart Ventricles; Humans; Infant; Tachycardia

Amiodarone was administered to 121 patients (82 males, 39 females; average age 59 years) with refractory atrial tachyarrhythmias. All patients had experienced recurrent atrial fibrillation, atrial flutter, or reentrant supraventricular tachycardia previously refractory to digitalis drugs, beta-adrenergic blocking agents, and an array of membrance-active preparations. Seventy-four of 121 patients (61.2%) had no evidence of organic heart disease, whereas 17 patients experienced arrhythmia as a result of coronary heart disease, nine had preexcitation syndromes, 16 had primary valvular heart disease, and five patients, had congenital heart disease. Atrial fibrillation alone or in combination with atrial flutter was the primary dysrhythmia in 95 of 121 patients (78.5%), whereas in 26 patients (21.5%) supraventricular tachycardia was the primary refractory dysrhythmia. Fifty-one patients (42%) had experienced tachyarrhythmias for more than 10 years prior to the use of amiodarone. During an average follow-up of 27.3 months, complete suppression of atrial arrhythmias occurred in 98 of 121 patients (81%), and partial suppression occurred in seven (5.8%). In 16 patients (13.2%) the drug was deemed ineffective, and in eight patients (6.6%) amiodarone was discontinued because of intolerable side effects. The average blood serum concentration among successfully treated patients was 1.9 micrograms/ml, whereas the average concentration for those with side effects was 2.3 micrograms/ml. Thus, amiodarone is an extremely effective (greater than 85%) agent for refractory atrial tachyarrhythmias. Once daily administration, generally tolerable side effects, and excellent patient tolerance render this agent an attractive option for the management of these dysrhythmias.

Topics: Adolescent; Adult; Aged; Amiodarone; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Drug Evaluation; Drug Resistance; Female; Humans; Male; Middle Aged

In Wolff-Parkinson-White (WPW) syndrome, the two most commonly occurring arrhythmias are circus movement tachycardia (CMT) and atrial fibrillation (AF). In 70% of patients with clinically documented CMT in whom the arrhythmia could be initiated by programmed electrical stimulation of the heart, the same CMT could still be initiated after long-term oral amiodarone administration. Spontaneous clinical recurrence of the arrhythmia was, however, observed in only 10% of patients. This finding suggests that the beneficial effect of amiodarone on CMT is primarily based on the prevention of the CMT-initiating premature beat. This may also apply to atrioventricular nodal reentrant tachycardia, in which amiodarone is also extremely effective in preventing relapses. The role of amiodarone in other forms of reentrant, or ectopic, supraventricular tachycardias is less well defined. During AF in WPW syndrome, the ventricular rate is related to the duration of the anterograde refractory period of the accessory pathway. Amiodarone prolongs this value, resulting in the reduction of ventricular rate during AF. Unfortunately, in the presence of a short anterograde refractory period of the accessory pathway, amiodarone results in only a small amount of lengthening of this value. In these patients the beneficial effect of amiodarone may primarily be related to the prevention of episodes of AF. We also found that the effect of oral amiodarone on the duration of the anterograde refractory period of the accessory pathway can (1) be abolished by sympathetic stimulation with isoproterenol and (2) be predicted from the effect of ajmaline or procainamide given intravenously. These observations clearly have practical clinical implications.

Topics: Ajmaline; Amiodarone; Atrial Fibrillation; Benzofurans; Electrophysiology; Heart; Humans; Isoproterenol; Procainamide; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Arrhythmias may be controlled in most patients with recurrent supraventricular tachycardia or atrial fibrillation with small to moderate maintenance doses of amiodarone (100 to 400 mg/day). Moderate doses (400 mg/day) are also highly effective in suppressing "warning" ventricular arrhythmias in patients with chronic ischemic heart disease, particularly if the goal of treatment is to eliminate ventricular couplets, runs of ventricular tachycardia (VT), and the "R on T" phenomenon. Treatment and prevention of sustained recurrent VT and the malignant arrhythmias of chagasic myocarditis require, however, doses of about 800 mg/day, which may be higher than those needed for ischemic heart disease complicated by VT and ventricular fibrillation. Clinical studies suggest an elimination half-life for amiodarone of about 30 days (range 15 to 100 days). Thus there is a pretherapeutic latency period that varies according to the type of arrhythmia and the doses employed. The maximal effects (as well as the most significant adverse effects) are not attained before 90 to 150 days of treatment, and the antiarrhythmic protection may persist for varying intervals, up to 150 days or more, after the drug has been discontinued. Side effects are not negligible but are generally dose dependent. Despite these side effects, many patients have been treated by us with amiodarone for as long as 5 to 8 years--and for up to 10 years in some cases. Amiodarone appears to be one of the most promising drugs for the possible prevention of ventricular fibrillation and sudden death.

Topics: Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Chagas Cardiomyopathy; Dose-Response Relationship, Drug; Drug Interactions; Half-Life; Heart Ventricles; Humans; Kinetics; Wolff-Parkinson-White Syndrome

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Electric Countershock; Heart; Humans; Middle Aged

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digoxin; Female; Humans; Injections, Intravenous; Male; Middle Aged; Myocardial Infarction

Twenty-six consecutive patients (14 males, 12 females--mean age 66.6) were admitted to an intensive care unit (ICU) because of a rapid ventricular response to atrial fibrillation (RAF). Fourteen of them had been unsuccessfully treated by drugs (other than amiodarone) and/or DC shock before admission. A loading dose of i.v. amiodarone was administered (repeated boluses of 3 mg/kg in 3 min, or 30 min-infusions of 5 to 7.5 mg/kg), followed by continuous infusion, in order to reach a maximal total dosage of 1500 mg in 24 h. This treatment was considered efficacious if a reversion to stable sinus rhythm (SSR) occurred within 24 h and was maintained for more than 48 h. This was achieved in 21 out of 26 patients (80.8%). The mean time between the administration of therapy and the occurrence of SSR was 171 min. The total dose of amiodarone delivered to effect SSR was 6.9 +/- 2.3 mg/kg. No adverse reactions were encountered during the bolus injection but we recommend that continuous infusion be carried out through a central venous catheter to avoid phlebitis. The administration of 7 mg/kg of intravenous amiodarone delivered in 30 min proved a safe and successful first choice of management in atrial fibrillation with a rapid ventricular response.

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Dose-Response Relationship, Drug; Electrocardiography; Female; Humans; Infusions, Parenteral; Intensive Care Units; Male; Middle Aged; Sinoatrial Node

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Humans; Infusions, Parenteral; Male; Middle Aged; Myocardial Infarction

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Humans; Myocardial Infarction; Time Factors

Topics: Amiodarone; Arrhythmia, Sinus; Atrial Fibrillation; Benzofurans; Humans; Male

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Humans; Injections, Intravenous; Myocardial Infarction

Amiodarone has proved to be a valuable drug in atrial fibrillation associated with the Wolff-Parkinson-White syndrome. When it was administered to a patient with this syndrome in atrial fibrillation, who had previously suffered an inferior myocardial infarction, the ventricular rate accelerated from 170 to 230 beats/minute.This unusual case emphasises the need for full electrophysiological assessment of patients with the Wolff-Parkinson-White syndrome for whom amiodarone treatment is being considered.

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Humans; Male; Tachycardia; Wolff-Parkinson-White Syndrome

A 44-year-old woman is described in whom amiodarone, disopyramide, and quinidine, administered alone separately, induced atypical ventricular tachycardia (AVT, torsade de pointes). Following a closed mitral valvotomy, she received quinidine, 1.2 g/day, without interruption for 17 years. Because of a recurrence of paroxysmal atrial fibrillation, the dose of the drug was increased to 1.4 g/day; 24 hours later AVT with syncope developed but responded promptly to atropine. Two years later, 24 hours following an increase in the dose of disopyramide from 300 to 600 mg/day, AVT with syncope occurred; isoproterenol abolished the arrhythmia instantly. Amiodarone was the third drug to induce AVT in this patient; she received 200 mg/day six days per week for six months. The dose was subsequently increased to 200 and 400 mg/day on alternate days, six days per week, and two months later AVT occurred. That time the only effective treatment was ventricular pacing.

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Disopyramide; Dose-Response Relationship, Drug; Electrocardiography; Female; Heart Ventricles; Humans; Prajmaline; Pyridines; Quinidine; Tachycardia

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Drug Therapy, Combination; Female; Humans; Male; Middle Aged; Quinidine; Time Factors

The authors observed 127 patients with different disorders of the cardiac rhythm treated with ethmozine, cordarone and rhythmodan. To assess the efficacy of the therapy circadian ECG was recorded on a magnetic tape with a portable cardiomonitor, exercise tests (bicycle ergometry, treadmill and walking under ECG control) were conducted. Good effect was seen after a course of treatment in patients with ventricular and atrial extrasystolae, paroxysms of supraventricular, ventricular tachycardia and auricular fibrillation. Cordarone was found effective in the Wolff-Parkinson - White syndrome and paroxysms of supraventricular tachycardia.

Topics: Adult; Aged; Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Cardiac Complexes, Premature; Coronary Disease; Disopyramide; Drug Evaluation; Electrocardiography; Exercise Test; Female; Humans; Male; Middle Aged; Moricizine; Morpholines; Phenothiazines; Pyridines; Tachycardia

Topics: Aged; Ambulatory Care; Amiodarone; Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Digoxin; Humans; Middle Aged

Amiodarone was used in 30 patients with tachyarrhythmias refractory to treatment with several antiarrhythmic agents. In 18 patients with supraventricular arrhythmias (recurrent atrial tachycardia in seven; atrial fibrillation, recurrent in four and persistent in five; Wolff-Parkinson-White syndrome in two), complete control was obtained in eight and marked improvement in eight patients. Conversion of persistent atrial fibrillation to sinus rhythm was documented in three patients. Congestive heart failure improved markedly in three patients who had persistent atrial fibrillation during amiodarone therapy. In 12 patients with tachycardia of ventricular origin effective control was obtained in nine. The incidence of side effects was low. Amiodarone is effective in maintaining sinus rhythm in many patients with both supraventricular and ventricular tachyarrhythmias when standard antiarrhythmic agents have failed.

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Female; Heart Atria; Heart Ventricles; Humans; Male; Middle Aged; Recurrence; Tachycardia; Wolff-Parkinson-White Syndrome

3 patients with atrial fibrillation, of varying origin, have been successfully converted to sinus rhythm by D.C. shock while on the antiarrhythmic drug amiodarone. D.C. shock did not cause rhythm disturbance. D.C. conversion may not be contraindicated in patients taking amiodarone.

Topics: Adult; Amiodarone; Atrial Fibrillation; Benzofurans; Electric Countershock; Female; Humans; Male; Middle Aged

The Authors tested the effectiveness of amiodarone hydrochloride i.v. in 50 cases of supraventricular hyperkinetic arrhythmias recently aroused. 50 patients, aged 41 to 85 years, with paroxysmal supraventricular tachycardia (PSVT, 21 cases), atrial flutter (7 cases) or fibrillation (22 cases) were treated with 4 mg/Kg of body weight of amiodarone i.v. over 2 min., followed by other 1500 mg/24 hours over 48 hours while amiodarone per os was started for antiarrhythmic prophylaxis; a 12 leads surface ECG and blood pressure were periodically recorded. The sinus rhythm was restored within 3 hours in every case of PSVT (100% of success), within 30 hours in 19 cases of atrial fibrillation (86% of success) and in 5 cases of atrial flutter (71% of success). A slowing down of ventricular frequency ranging from 15 to 40% occurred within 10 min. in case of failure of restoration of sinus rhythm; a slight and transient lengthening of P-R occurred in 1 case; no particular side effects nor noteworthy changes of blood pressure were observed. Amiodarone i.v. proved to be a very effective remedy, handy and well tolerated for the arrhythmias considered above.

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Female; Humans; Injections, Intravenous; Male; Middle Aged; Tachycardia, Paroxysmal

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Female; Humans; Male; Middle Aged

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Humans; Injections, Intravenous; Middle Aged

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Digitalis Glycosides; Echocardiography; Electric Countershock; Female; Follow-Up Studies; Humans; Male; Middle Aged; Quinidine; Verapamil

Topics: Adult; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiomyopathies; Female; Heart Valve Diseases; Humans; Male; Middle Aged; Mitral Valve; Quinidine

Oral amiodarone has been used to treat 21 patients with various supraventricular arrhythmias; 13 had Wolff-Parkinson-White syndrome, which was complicated by atrial fibrillation and re-entry atrioventricular tachycardia in four, and re-entry tachycardia alone in the other nine. The remaining eight patients had paroxysmal atrial fibrillation or flutter without pre-excitation. All were refractory to conventional treatment and had undergone intracardiac electrophysiological study. Fifteen have been controlled with amiodarone, this treatment proving most effective in atrial fibrillation or flutter with or without pre-excitation. Amiodarone was successful in only four of the nine patients with re-entry atrioventricular tachycardia. In two patients who responded well the drug had to be discontinued because of side effects.

Topics: Adult; Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Electrocardiography; Humans; Middle Aged; Wolff-Parkinson-White Syndrome

Oral amiodarone, an iodine-containing antiarrhythmic agent, was administered to 72 patients with recurrent paroxysmal tachycardias. Thirty-nine patients had tachycardias associated with the Wolff-Parkinson-White syndrome, 15 patients had paroxysmal atrial fibrillation unassociated with the Wolff-Parkinson-White syndrome, and 18 patients had ventricular tachycardia. In all patients, the frequency of symptomatic attacks had not been reduced by at least three other antiarrhythmic agents alone or in combination. The response to amiodarone treatment was graded according to the patients' subjective response (total suppression, partial suppression, and no effect). Overall, 57 per cent of patients had total abolition of attacks and another 22 per cent had a partial suppression of attacks. Side effects, the most common of which were photosensitivity and gastrointestinal upsets, occurred in 44 per cent and were sufficiently severe to warrant withdrawal of treatment in 15 per cent. These results confirm that amiodarone is of considerable value in the treatment of recurrent paroxysmal arrhythmias resistant to other drugs.

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Child; Drug Administration Schedule; Humans; Middle Aged; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Amiodarone; Angina Pectoris; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Humans; Tachycardia

Topics: Adolescent; Adult; Aged; Amiodarone; Atrial Fibrillation; Atrioventricular Node; Benzofurans; Cardiac Pacing, Artificial; Electric Stimulation Therapy; Electrocardiography; Female; Heart Conduction System; Heart Rate; Humans; Male; Middle Aged; Refractory Period, Electrophysiological; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Amiodarone; Atenolol; Atrial Fibrillation; Benzofurans; Electrocardiography; Heart Rate; Humans; Propanolamines

The employment of Cordaron (Amidaron) in 50 patients with different arrhythmias proved effective in 86% of the cases. Cordaron was most effective in the treatment and prevention of paroxysmal tachycardia, ventricular extrasystole, paroxysmal cardiac fibrillation. It decreases the pulse rate and moderately decreases the arterial pressure without imparing the patients' state. The drug has practically no toxic effect, is well tolerated, convenient for administration and dosage. Cardiovascular insufficiency is no contraindication for its prescription. Carefulness is needed in prescribing Cordaron to patients with atrioventricular conductivity disorders.

Topics: Aged; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiac Complexes, Premature; Drug Evaluation; Female; Hemodynamics; Humans; Male; Middle Aged; Myocardial Contraction; Tachycardia, Paroxysmal

Topics: Aged; Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Humans; Male; Wolff-Parkinson-White Syndrome

Topics: Amiodarone; Atrial Fibrillation; Benzofurans; Electrocardiography; Heart Rate; Humans; Injections, Intravenous

Topics: Adult; Aged; Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Digoxin; Female; Humans; Male; Middle Aged; Myocardial Infarction; Pulmonary Heart Disease; Rheumatic Heart Disease

Topics: Amiodarone; Atrial Fibrillation; Atrial Flutter; Benzofurans; Digitalis Glycosides; Humans

The effect of amiodarone in the Wolff-Parkinson-White syndrome was studied with programmed electrical stimulation of the heart in 15 patients. All 15 patients had circus movement tachycardias; 7 also had atrial fibrillation. Programmed electrical stimulation was performed before and after 14 days of oral administration of amiodarone. The effective refractory period of the accessory pathway lengthened in an atrioventricular direction in all patients and in a ventriculoatrial direction in eight patients. The effective refractory period of the atrium and ventricle lengthened in 14 and 12 patients, respectively. After administration of amiodarone, circus movement tachycardia could no longer be initiated in five patients. The zone of tachycardia narrowed in four patients, did not change in two and increased in seven. The effect of amiodarone on initiation of circus movement tachycardia could be related to differences in effect of the drug and in the mechanism of tachycardia in individual patients. In all patients in whom tachycardias could still be initiated after treatment with amiodarone the heart rate during tachycardia was slower than before treatment. This slowing was caused by a decrease in conduction velocity of the circulatory wave in different parts of the tachycardia circuit. The effect of amiodarone in prolonging the refractory period of the accessory pathway makes this drug especially useful in patients with the Wolff-Parkinson-White syndrome and atrial fibrillation.

Topics: Adolescent; Adult; Amiodarone; Atrial Fibrillation; Atrioventricular Node; Benzofurans; Electrocardiography; Female; Heart Atria; Heart Ventricles; Humans; Male; Middle Aged; Neural Conduction; Pacemaker, Artificial; Refractory Period, Electrophysiological; Tachycardia; Wolff-Parkinson-White Syndrome

Topics: Adolescent; Adult; Aged; Anti-Arrhythmia Agents; Atrial Fibrillation; Atrial Flutter; Benzofurans; Cornea; Female; Heart Conduction System; Humans; Male; Middle Aged; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Adrenergic beta-Antagonists; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Digitalis Glycosides; Electric Countershock; Lidocaine; Phenytoin; Potassium; Procainamide; Quinidine; Tachycardia; Verapamil

Topics: Anti-Arrhythmia Agents; Atrial Fibrillation; Benzofurans; Heart Ventricles; Humans; Tachycardia

Topics: Adult; Aged; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Female; Humans; Male; Middle Aged; Tachycardia

Topics: Angina Pectoris; Antihypertensive Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Cardiac Complexes, Premature; Humans; Tachycardia; Tachycardia, Paroxysmal

Topics: Acetylcholine; Animals; Arrhythmias, Cardiac; Atrial Fibrillation; Barium; Benzofurans; Cardiac Complexes, Premature; Chlorides; Dogs; Rabbits; Strophanthins; Tachycardia