Long-Term Outcomes of Surgical Ablation for Atrial Fibrillation: Impact of Ablation Lesion Sets.

Background: The lesion sets for surgical ablation of atrial fibrillation (AF) that provide optimal outcomes have remained controversial. Objectives: We evaluated the effects of left-atrial (LA) ablation of AF compared with bi-atrial (BA) ablation on the clinical and rhythm outcomes, and examined the predictors for AF recurrence and permanent pacing in consideration of ablation lesion sets. Methods: Between 2001 and 2018, 1,965 patients underwent surgical ablation during cardiac surgery at our institution. Among these, 796 and 1,169 patients underwent LA and BA ablation, respectively. The clinical outcomes were evaluated after propensity score adjustment, with death accounting for a competing event. The probability of AF recurrence was estimated with the generalized estimating equations model. Results: The patients with BA ablation had morbidities greater than those with LA ablation. The probability of AF recurrence at 1 and 5 years was 13.9% and 37.1% in patients with LA ablation, and 11.2% and 30.1% in those with BA ablation (hazard ratio [HR]: 1.24; 95% confidence interval [CI]: 0.96-1.61; P = 0.100). After adjustment, LA ablation was associated with a decreased risk of early death (<30 days) (odds ratio [OR]: 0.56; 95% CI: 0.31-0.96; P = 0.041) and new-onset dialysis (OR 0.47; 95% CI: 0.27-0.78; P = 0.003). However, the risk of overall mortality (HR: 1.03; 95% CI: 0.75-1.41; P = 0.878) and permanent pacing (HR: 0.68; 95% CI: 0.43-1.06; P = 0.091) was comparable between the 2 groups. Conclusions: The risk of AF recurrence and adverse events was comparable between the 2 ablation lesion sets. BA ablation was not related to an increased risk of permanent pacing.