Sotalol Versus Quinidine Verapamil For Conversion Of Chronic Atrial-Fibrillation And Maintenance Of Sinus Rhythm - A Randomized Study

Atrial fibrillation is one of the most common arrhythmias, leading at least in a subset of patients to severe symptoms (palpitations, weakness, syncope), and to hemodynamic impairment especially in the clinical setting of left ventricular dysfunction. Thus, in many cases resaturation of sinus rhythm is indicated because of the negative effects of reduced cardiac output. Quinidine has been the first line drug for many years and has been proven to be highly effective especially when combined with Verapamil. But there is growing concern about using quinidine and other class I-antiarrhythmic agents because of some hints in clinical trials for increased longterm mortality on these drugs.This study was undertaken to test the efficacy of Sotalol, a beta-blocker with additional strong class-ill antiarrhythmic action, compared to a fixed combination of Quinidine and Verapamil for conversion of chronic atrial fibrillation and maintenance of sinus rhythm after medical or electrical cardioversion. To avoid early proarrhythmic effects, potassium values in the range of ''high''-normal values (> 4,3 mval/L) were tried to be obtained.82 patients were randomly assigned to receive either Sotalol or Quinidine/Verapamil. There was no difference between the groups as far as the underlying heart disease, duration of atrial fibrillation (mean 219 days) and other clinical features including echocardiographic parameters were concerned. The dose of the drug was weight-related individually adjusted, and the drug was continued thereafter. If sinus rhythm could not be established at that time, electric cardioversion was performed and the drug was continued in lower dosage thereafter.67% of the patients receiving Quinidine/Verapamil, but only 24% of those receiving Sotalol converted to sinus rhythm during the 10-day period. The difference is statistically significant (p < 0.001). All but 1 of the remaining patients could be converted to sinus rhythm electrically. After 6 and 12 months, 75.7% and 67.3% of the Quinidine/Verapamil-treated patients still remained in sinus rhythm in opposition to 63.4 and 49.9% of the Sotalol group. This is statistically not significant. 5 patients in the Quinidine/ Verapamil group discontinued treatment because of non-cardiac side effects. Totally 3 patients in the Sotalol group were withdrawals because of symptomatic bradycardia and dyspnoea. Proarrhythmia was noted not in a single case for both drugs.