Comparative efficacy and safety of allapinine, ethacyzin and amiodarone: choice of optimal antiarrhythmic therapy for rhythm control in case of paroxysmal atrial fibrillation
AbstractTo compare the efficacy and safety of allapinine, ethacyzin and amiodarone in preventing paroxysms of atrial fibrillation and/or flutter resistant to class IA antiarrhythmic drugs a randomized open parallel study was conducted followed by crossover serial testing in nonresponders to the first drug to fined optimal therapy with single drug. Ninety patients with frequent attacks of atrial fibrillation objectified by 12-lead electrocardiogram were treated with allapinine 75–200 mg/day (n=33) or ethacyzin 150–200 mg/day (n=38) or amiodarone 200–400 mg/day (n=19) as first drugs. The primary end point of the study was inefficacy or intolerability of the treatment with selected drug. The secondary end point was the time interval to the first attack of arrhythmia. Efficacy was considered if attacks be less frequent, briefer, and less symptomatic. In case of effective and well tolerated treatment follow-up continued for a period of 3 months. On allapinine as first drug events of primary end point were significantly less frequent compared with ethacyzin (RR=0.09; 95 % CI 0.040.2; p<0.0001) and with amiodarone (RR=0.22; 95 % CI 0.090.5; p<0.016). When optimal drug therapy was compared with first drug therapy RR was 1.37 (95 % CI 2.910.7; p<0.002) and NNT=4.5. The high efficacy of allapinine in nonresponders to the first drugs was resulted in general to the ratio. In conclusion: allapinine is effective and safe antiarrhythmic drug in preventing paroxysms of atrial fibrillation, and pharmacological therapy failure may by conclude only as a result of serial drug testing but not as failure to «at least 1 class I or III antiarrhythmic medication».
Keywords:allapinine, ethacyzin, amiodarone, antiarrhythmic therapy, rhythm control, paroxysmal atrial fibrillation