Comparative Study of the Efficacy and Safety of Sotalol and Amiodarone for the Treatment of Symptomatic Chronic Ventricular Arrhythmias

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Abstract

Background and objectives Sotalolis a non-selective beta-adrenoceptor antagonist that prolongs the action potential duration and lengthens the refractory period in both the atria and the ventricles. The aim of this study is to determine the efficacy and safety of sotalol compared with amiodarone. Methods Eleven consecutive patients with chronic ventricular premature contractions were analyzed prospectively. Results Sotalol (160 mg or 320 mg, divided into two doses per day) significantly reduced ventricular premature contractions (77%) within 3 days of dosing. The percent suppression of total ventricular premature contractions per hour with amiodarone was 95.8%. Individual efficacy was achieved in 9 patients (81.8%) with sotalol and in all patients with amiodarone. The major electrocardiographic effects of sotalol were a decrease in heart rate (20.2%) and a prolongation of the. QT interval(15.8%), but neither a deterioration of cardiac function nor proarrhythmia were seen. Sotalol was better tolerated with low doses (160 mg) as compared with high doses (320 mg). Adverse effects (elevation of liver enzymes, gastroenterological disturbances, bradycardia and QT prolongation) were noticed with amiodarone, although the total dose of 22.2 g was mostly well tolerated.   Conclusions Despite the lower antiarrhythmic efficacy observed in comparison with amiodarone, sotalol appears to be safe for the treatment of symptomatic ventricular ectopic activity due to its low side effect profile and fast on set of antiarrhythmic action.