Do We Need to Open the Left Atrium for Surgical AF Ablation in Paroxysmal AF Concomitant to CABG or AVR?

Objectives: In patients with paroxysmal AF undergoing CABG or AVR, many surgeons are reluctant to open the left atrium to perform a complete left-sided Cox-Maze lesion set. Isolated PVI is often preferred in those patients. We here analyzed rhythm course and outcome of patients with PVI compared with those receiving an extended left atrial lesion set.

Methods: Between 01/2003 and 06/2015, 620 patients, underwent concomitant surgical AF ablation in our institution. 206 patients with paroxysmal AF were treated with surgical ablation concomitant to AVR or CABG. 63 patients received a complete Cox Maze left atrial lesion set, while 143 patients were treated with an isolated pulmonary vein isolation. There were no statistically significant differences regarding baseline patient characteristics. Primary endpoint of the study was freedom from AF at 12 months follow-up.

Results: No major ablation-related complications occurred in any of the groups. In PVI group, 3 patients (2.1%) experienced intraoperative stroke, while 1 (1.2%) of patients had a stroke in extended LA ablation group. In patients receiving extended LA lesion set, mean cross clamp time was 18 ± 6.3 minutes longer, compared with PVI group. In-hospital mortality was 3.1% in PVI group, and 2.1% in extended LA group (p = 0.34). Freedom from AF at 12 months follow-up was 77% in extended LA ablation group versus 73% in PVI group, showing no statistically significant difference (p = 0.25). A higher rate of symptomatic left atrial flutter was observed in PVI group, compared with extended LA group (n = 3; 4.7% vs 0% p = 0.32).

Conclusion: Surgical AF ablation concomitant to CABG or AVR in patients with paroxysmal AF is safe and effective. There was no statistically significant difference between PVI and extended LA lesion set regarding freedom from AF rate after 12 months. Patients in extended LA group had a longer cross-clamp time, but fewer rate of postoperative left-atrial flutter. Thus, PVI may be sufficient in this patient population.