Survival after surgical ablation for atrial fibrillation in mitral valve surgery: Analysis from the Polish National Registry of Cardiac Surgery Procedures (KROK)

Abstract

Objectives: Surgical ablation for atrial fibrillation (AF) performed at the time of other valvular- or nonvalvular cardiac procedure is a mainstay of therapy; yet the data regarding its influence on remote survival are sparse. We aimed to evaluate late survival in patients undergoing mitral valve (MV) surgery with concomitant surgical ablation for AF.

Methods: Procedure-related data from the Polish National Registry of Cardiac Surgery Procedures (Krajowy Rejestr Operacji Kardiochirurgicznych) were retrospectively collected. A total of 11,381 patients with baseline AF (46.6% men; mean age 65.6 ± 9.0 years) undergoing MV surgery between 2006 and 2017 in 37 reference centers across Poland and included in the registry were analyzed. Median follow-up was 5 years (mean, 4.6 years; interquartile range, 1.9-7.9 years). Cox proportional hazards models were used for computations. Propensity score matching for the comparison of MV + ablation versus MV alone was performed.

Results: Of included patients, 2449 (21.5%) underwent surgical ablation for AF. Patients in this group were significantly younger (63.8 ± 8.7 years vs 66.1 ± 9.0 years; P < .001) and were at lower baseline surgical risk (EuroSCORE, 2.86 vs 3.69; P < .001). During the 12-year study period, there was a significant survival benefit (hazard ratio, 0.71; 95% confidence interval, 0.63-0.79; P < .001) for MV + ablation compared with MV alone. After rigorous propensity matching (logit model, 1784 pairs) surgical ablation was associated with nearly 20% improved survival (hazard ratio, 0.82; 95% confidence interval, 0.70-0.96; P = .011). Benefit of surgical ablation was maintained in subgroup analyses, yet most benefit was appraised in low-risk patients such as those with EuroSCORE of 2 to 5 or age < 50 years.

Conclusions: Concomitant surgical ablation for AF in patients undergoing mitral valve procedures is safe, feasible, and significantly improves late survival.

Keywords: atrial fibrillation; long-term results; mitral valve; registry; surgical ablation.