Left Atrial Size Reduction Improves the Sinus Rhythm Conversion Rate after Radiofrequency Ablation for Continuous Atrial Fibrillation in Patients Undergoing Concomitant Cardiac Surgery

Abstract
Background: Radiofrequency (RF) ablation can effectively restore sinus rhythm in the majority of patients with continuous atrial fibrillation (AF). However, no previous randomized studies have discussed the association of left atrial size reduction and the improvement of sinus rhythm conversion rate after radiofrequency ablation for continuous AF. Methods: This prospective randomized study included 46 patients with continuous AF and cardiac disease. Twenty patients underwent cardiac surgery and radiofrequency ablation (group I). The other 26 patients underwent cardiac surgery and RF ablation combined with left atrial size reduction (group II). The patients were followed for one year postoperatively. Rhythm, neurological complications, and left atrial size were evaluated. Results: At the one-year follow-up sinus rhythm was restored in 61.1 % of patients in group I and 77.3 % of patients in group II. LA diameter, evaluated by echocardiography, was reduced from 60 ± 15 mm to 55 ± 8 mm in group I and from 69 ± 19 mm to 51 ± 8 mm in group II. One case of stroke was observed postoperatively in each group. In group I one patient suffered a transient ischemic attack. Two patients in each group received transvenous permanent pacemaker implantation. Conclusion: Left atrial size reduction improves sinus rhythm conversion rate after RF ablation for continuous atrial fibrillation in patients undergoing concomitant cardiac surgery.