Low-energy internal cardioversion of atrial fibrillation after failed external cardioversion: Texas Heart Institute experience and review of the literature.

In patients with atrial fibrillation, low-energy internal cardioversion may be used to restore sinus rhythm after external cardioversion fails. We used this method in 8 consecutive patients with a mean age of 69.5+/-8.3 (SD) years, 7 (87.5%) of whom were successfully treated with a mean 9.1 J (range, 4 to 14 J). No patient had ventricular arrhythmias at the time of cardioversion, or local groin complications afterward. One patient had recurrent atrial fibrillation the morning after cardioversion, and another patient had an embolus to the renal artery 20 days posttreatment. After 1 month, 5 patients were still in sinus rhythm, and 1 patient was lost to follow-up. This study confirms the efficacy of internal cardioversion in this setting and stresses the importance of a standard anticoagulation protocol before and after cardioversion.