The purpose of our study was to evaluate the efficacy of antiarrhythmic drugs amiodarone, propafenone and etacizine in patients with paroxysmal and persistent atrial fibrillation (AF) depending on the type of paroxysms. We examined 167 patients, average age 53.8±0.9 years, among them 113 patients with paroxysmal (n=81) and persistent (n=32) AF without significant structural heart disease. 23.9 % of patients had single ventricular premature beats and didn’t have other arrhythmias. The control group included 16 patients with hypertension without AF, 18 patients with chronic ischemic heart disease without AF and 20 patients – rather healthy men without any cardiac pathology and AF). The most effective drugs to maintain sinus rhythm in adrenergic AF were propafenone and amiodarone, in vagal AF – etacizine and amiodarone.