The pharmacologic treatment of atrial fibrillation

Abstract

The pharmacologic treatment of atrial fibrillation (AF) is aimed at controlling the ventricular response, restoring sinus rhythm, and preventing or delaying relapses. In the control of ventricular response, digitalis maintains a primary role when the arrhythmia is accompanied by heart failure. In ischemic, hypertensive, and degenerative (whose number is increasing at present) cardiopathies without evident ventricular dilatation, treatments with calcium antagonists (such as verapamil, gallopamil, or diltiazem) or beta-blocking agents must be preferred. In order to control the ventricular response in patients with chronic AF during physical activity, the association of digitalis with beta-blocking agents or calcium antagonists seems to provide satisfactory results. The drugs of the IC class, especially flecainide, represent a certain therapeutical progress in the restoration of sinus rhythm in the treatment of paroxysmal atrial fibrillation affecting subjects without evident alterations of ventricular function, particularly in subjects with Wolff-Parkinson-White syndrome, with forms of vagal origin, or with atrial fibrillation alone. A therapeutic combination of digitalis and quinidine may produce resolution of the arrhythmia in the presence of altered ventricular function or when AF is of an uncertain onset. In patients with hypertensive, ischemic, and/or degenerative cardiopathy without evident ventricular or advanced heart failure, the verapamil-quinidine association may also be effective and even quicker. The combination of drugs of the I and III class for restoration of the sinus rhythm in particularly resistant forms of AF without evident structural heart alterations is promising but must be verified in a greater number of patients. In the prevention of relapses amiodarone appears to have the widest spectrum of advantages from an electrophysiologic point of view; however, because of its many side effects, amiodarone represents a late therapeutical choice. The promising results obtained with flecainide are disputed by the results of the CAST, which limit the possibilities of using this drug to a low number of cases (W.P.W. syndrome, AF of vagal origin, atrial fibrillation alone). In the past, quinidine and disopyramide have been the drugs most widely used in the prophylaxis of AF. These drugs have a similar efficacy, and both of them provided some positive results. However, because of untoward side effects (especially for quinidine) during chronic treatment, the use of these drugs has been questioned. Perhaps in the majority of patients, the less dangerous therapeutic choice after the termination of the fibrillation is a combination of drugs slowly down AV node activity (digitalis or calcium antagonists and beta blockers) with class IA antiarrhythmics.

Intravenous propafenone in paroxysmal atrial fibrillation: A randomized, placebo‐controlled, double‐blind, multicenter clinical trial

“…lo-I 1 Nevertheless, arising concern about the r i s h n e f i t ratio of this "secondary prevention" of AF with drugs of class IC is shared by many experts in this field because ofthe potential proarrhythmic effect shown in patients with postmyocardial infarction as well as in those with atrial fibrillation.'2. l 3 Our data show that propafenone is an effective therapeutic option in the acute treatment of patients with paroxysmal AF of recent onset, provided that the drug is given in patients without signs of left ventricular failure. The percentage of patients who return in sinus rhythm is almost twofold higher for those treated with the active drug.…”

Antiadrenergic Therapy in the Control of Atrial Fibrillation

“…Class II (β-blockers) and intravenous (dihydropyridine calcium-channel blockers) agents are generally far less effective as they restore sinus rhythm in fewer than 20% of patients. Digoxin has been used with only limited success (26,29).…”

Atrial Fibrillation and Flutter: Maintaining Stability of Sinus Rhythm Versus Ventricular Rate Control

“…myocardial infarction (1). cerebrovasculiir accident (2). and suicide (I)-In the other 5 deaths in ihe quinidine group, although the mode of death was unclear, important concurrent medical illnesses including carcinoma (2).…”