SOTALOL VERSUS QUINIDINE VERAPAMIL FOR CO NVERSION 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, weakne ss, syncope), and to hemodynamic impairment especially in the clinical setting of left ventricular dysfunction. Thus, in many cases resatura tion of sinus rhythm is indicated because of the negative effects of r educed cardiac output. Quinidine has been the first line drug for many years and has been proven to be highly effective especially when comb ined with Verapamil. But there is growing concern about using quinidin e and other class I-antiarrhythmic agents because of some hints in cli nical trials for increased longterm mortality on these drugs. This stu dy was undertaken to test the efficacy of Sotalol, a beta-blocker with additional strong class-ill antiarrhythmic action, compared to a fixe d combination of Quinidine and Verapamil for conversion of chronic atr ial fibrillation and maintenance of sinus rhythm after medical or elec trical cardioversion. To avoid early proarrhythmic effects, potassium values in the range of ''high''-normal values (> 4,3 mval/L) were trie d to be obtained. 82 patients were randomly assigned to receive either Sotalol or Quinidine/Verapamil. There was no difference between the g roups as far as the underlying heart disease, duration of atrial fibri llation (mean 219 days) and other clinical features including echocard iographic parameters were concerned. The dose of the drug was weight-r elated individually adjusted, and the drug was continued thereafter. I f sinus rhythm could not be established at that time, electric cardiov ersion was performed and the drug was continued in lower dosage therea fter. 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 ele ctrically. After 6 and 12 months, 75.7% and 67.3% of the Quinidine/Ver apamil-treated patients still remained in sinus rhythm in opposition t o 63.4 and 49.9% of the Sotalol group. This is statistically not signi ficant. 5 patients in the Quinidine/ Verapamil group discontinued trea tment because of non-cardiac side effects. Totally 3 patients in the S otalol group were withdrawals because of symptomatic bradycardia and d yspnoea. Proarrhythmia was noted not in a single case for both drugs.