Atrial fibrillation ablation in patients undergoing aortic valve replacement

Current guidelines suggest that the use of a mechanical prosthesis is favored when patients are already receiving long-term anticoagulation for conditions such as atrial fibrillation (AF). Surgical AF ablation can restore normal sinus rhythm (NSR) and obviate the need for anticoagulation. The study aim was to determine the impact of concomitant AF ablation in patients with AF undergoing aortic valve replacement (AVR) on the restoration of NSR and subsequent requirement for anticoagulation.

Between April 2004 and December 2009, a total of 124 patients (mean age 74 +/- 12 years) with pre-existing AF underwent AVR with or without coronary artery bypass grafting. The documented preoperative rhythm was long-standing persistent AF in 39 patients (32%), persistent AF in five (4%), and paroxysmal AF in 80 (65%). Eighty patients (65%) had concomitant surgical AF ablation. In the ablation group, bilateral pulmonary vein isolation was performed in 55 cases (69%), left atrial-maze in 15 (19%), and Cox-maze in 10 (13%). A left atrial appendage closure was performed in 70 patients (88%). Sinus rhythm, in addition to anti-arrhythmic and warfarin use, were assessed between three and 15 months after surgery. Postoperatively, 13 patients died and 18 were lost to follow up during the three- to 15-month window; consequently, 71 patients were available for analysis in the ablation group, and 22 in the non-ablation group.

In-hospital mortality was 4% (the Ambler score predicted a median (IQR) of 6 (4-9)%). Freedom from AF when not receiving anti-arrhythmic drugs (AADs) occurred in 58 patients (82%) in the ablation group, compared to eight (36%) in the non-ablation group (p < 0.001). Fifty patients (70%) were free from warfarin in the ablation group, compared to six (27%) in the non-ablation group (p < 0.001). No differences were identified in freedom from AF between the surgical AF lesion sets. AF ablation, younger age, and paroxysmal AF were independently associated with freedom from AF when not receiving AADs.

Surgical AF ablation is associated with an improved restoration of NSR in patients with AF requiring AVR. The need for anticoagulation is reduced in the majority of patients. A bioprosthetic valve may be an acceptable option for a patient with AF who requires AVR.