EFFECTIVENESS OF AMIODARONE AND ELECTRICAL CARDIOVERSION FOR CHRONIC RHEUMATIC ATRIAL-FIBRILLATION AFTER MITRAL-VALVE SURGERY

Thirty consecutive patients with chronic rheumatic atrial fibrillation (AF) greater-than-or-equal-to 3 months after successful mitral valve surgery and left atrial diameter, 60 mm were treated with oral amiodar one. Protocol included high loading dosages of amiodarone for 4 weeks, and if conversion to sinus rhythm (SR) was not achieved then electric al cardioversion was performed. Patients converted to SR were maintain ed on low-dose amiodarone for another 4 weeks when treatment was disco ntinued. Overall, 23 patients (77%) converted to SR after 4 weeks of t herapy: 12 (40%) taking amiodarone alone and 11 (37%) with the additio n of electrical cardioversion. The duration of AF > 48 months was an a dverse factor in the ability to restore SR. Sixteen patients (70%) rem ained in SR at a mean follow-up of 17 months. The duration of AF less- than-or-equal-to 48 months alone or in combination with left atrial di ameter greater-than-or-equal-to 45 mm were the best predictors for lon g-term maintenance of SR. Thus, short-term amiodarone with or without electrical cardioversion is effective and safe in the treatment of chr onic rheumatic AF after mitral valve surgery. The duration of AF and l eft atrial size can be used to identify patients with successful outco me.