Low-energy cardioversion versus medical treatment for the termination of atrial fibrillation after CABG

Abstract

Background Atrial fibrillation (AF) is the most frequent complication after cardiac surgery and can cause considerable morbidity. Low-energy cardioversion (LEC) using biatrial epicardial wires implanted during surgery has been shown to be effective and safe in conscious patients, but has not been directly compared with medical treatment so far. We therefore prospectively studied the efficacy of LEC in men 60 years of age and older. Methods Sixteen patients (mean ± SD, 66.4 ± 5.4 years) were randomized to LEC and 32 patients (66.3 ± 5.0 years) to standarized medical treatment in the event of postoperative AF. Age, comorbidity, and surgical variables did not differ significantly between the groups. Results After cardiac surgery, AF occurred in 6 patients (38%) assigned to LEC and in 11 patients assigned to medical treatment (34%; p = NS). Low-energy cardioversion restored sinus rhythm in all but 1 patient, and 1 patient in the LEC group had early recurrence of AF. All other patients in the LEC group had prompt and stable restoration of sinus rhythm. Medical treatment was associated with the restoration of sinus rhythm in all patients. Although the total time in AF was decreased significantly by LEC (median 5 minutes versus 22 hours; p = 0.037), the length of postoperative hospitalization was not (5.1 ± 1.4 days for the LEC group compared with 5.3 ± 1.6 days for controls). Conclusions Low-energy cardioversion significantly decreased the amount of time cardiac surgery patients spent in AF after the operation. Larger studies are needed to determine whether this new treatment modality has the ability to decrease morbidity associated with postoperative AF and is cost-effective.