[Predictive factors of maintenance of sinus rhythm after direct current (DC) cardioversion of atrial fibrillation/atrial flutter].

INTRODUCTION: Our aim was to determine the immediate and long-term outcome of direct current (DC) electrical cardioversion in patients with atrial fibrillation or flutter, and to determine factors predicting clinical outcome.

MATERIALS AND METHODS: A retrospective one-year follow-up study of 220 patients with atrial fibrillation or flutter undergoing electrical cardioversion between September 1998 and April 2001 was done.

RESULTS: Electrical cardioversion was successful in 82% of the patients. Multivariate analysis revealed that female gender was associated with successful cardioversion (p=0.008). Only 29% remained in sinus rhythm after the one-year follow-up. Maintenance of sinus rhythm was associated with anti-arrhythmic drug treatment (p=0.042). Relapse of atrial fibrillation was associated with reduced left ventricular ejection fraction (p=0.002). Complications occurred in 7.7% of the electrical cardioversions; of these, 1.2% were thromboembolic events.

DISCUSSION: Less than one third of the patients remained in sinus rhythm after the one-year follow-up despite the use of anti-arrhythmic drugs. Electrical cardioversion is not without risk. Thorough consideration of choice of treatment in patients with atrial fibrillation or flutter is therefore important. According to Danish and international guidelines, electrical cardioversion should be considered primarily when symptoms of AF are unacceptable despite optimal frequency regulation or in patients with AF detected for the first time.