[Effects of amiodarone versus sotalol in treatment of atrial fibrillation: a random controlled clinical study].

OBJECTIVE: To evaluate the effects and adverse reactions of amiodarone and sotalol in treatment of atrial fibrillation.

METHODS: One hundred and two patients with atrial fibrillation, 56 males and 46 females, aged 56 +/- 11, were randomized into 2 equal groups: amiodarone group, taking amiodarone 600 mg/d for 7 days, 400 mg/d for 7 days, 200 mg/d for 7 days, and then 200 mg/d as maintenance dosage if conversion to sinus rhythm occurred; and sotalol group, taking sotalol 40-80 mg/d for one week, 160 mg/d for 2 weeks and then 40-80 mg/d as maintenance dosage if conversion to sinus rhythm occurred. If the cardiac rhythm failed to be converted to sinus rhythm after three week the medication was stopped. All the patients were followed up for 12-24 months and therapeutic effects were evaluated by echocardiography, electrocardiogram and Holter monitor.

RESULTS: (1) Conversion to sinus rhythm occurred in 40 patients in the amiodarone group with an effective rate of 78.4%, and in 36 patients in the sotalol group with an effective rate of 70.6%. (2) Conversion to sinus rhythm occurred in the first week in 34 patients of the amiodarone group and in 10 patients of the sotalol group. (3) 67.5% of the patients with conversion to sinus rhythm in the amiodarone group and 41.7% of the patients with conversion to sinus rhythm in the sotalol group maintained sinus rhythm in the following 12 months; and 44.4% patients with conversion to sinus rhythm in the amiodarone group and 26.7% of the patients with conversion to sinus rhythm in the following 24 months. (4) 10 patients in the sotalol group taking a maintenance dosage of 80 mg/d showed atrial ventricular block and severe bradycardia during the follow-up of 6-2 months, then the medication was stopped, but there was no severe arrhythmia in amiodarone group. (5) It was difficult to maintain sinus rhythm when atrial fibrillation lasting longer than 12 months was a predictive factor of failure to maintain sinus rhythm.

CONCLUSION: There is no significant difference between amiodarone and sotalol in converting atrial fibrillation to sinus rhythm. However, amiodarone is more effective in maintenance of sinus rhythm than sotalol. The adverse reaction of amiodarone on heart is less severe than that of sotalol.