Clinical impacts of concomitant left atrial appendage occlusion during mitral valve surgery in patients with mitral regurgitation

Abstract

Surgical occlusion of the left atrial appendage (LAA) during cardiac surgery in patients with atrial fibrillation (AF) is known to reduce thromboembolism. However, data on the clinical significance of LAA occlusion (LAAO) in patients with mitral regurgitation (MR) are lacking. A total of 237 AF patients with chronic severe MR who underwent mitral valve (MV) surgery were retrospectively analyzed. Patients were divided into two groups according to concomitant LAAO or LAA preservation. The primary outcome was a composite of all-cause death and thromboembolic events (ischemic stroke or systemic embolism). The LAA was surgically occluded in 98 (41%) patients and preserved in 139 (59%) patients. During the follow-up period (median, 37 months), 29 primary outcomes occurred. In the Kaplan-Meyer analysis, the LAA preservation group showed a greater cumulative incidence of the primary outcome (P = 0.002) and thromboembolic events (P = 0.003) than the LAAO group. In the univariate Cox regression analysis, coronary artery disease, CHA₂DS₂-VASc score, a cauliflower-shaped LAA, Maze, and no LAAO were significantly associated with the primary outcome. In the multivariate Cox regression analysis, concomitant LAAO was significantly linked to the primary outcome (hazard ratio [HR]: 0.30, 95% confidence interval [CI]: 0.10-0.91, P = 0.033) and thromboembolic events (HR: 0.19, 95% CI: 0.04-0.87, P = 0.032). These benefits from LAAO were consistent, even after propensity score-matched analysis. For patients undergoing surgery for chronic MR who also have AF, concomitant surgical LAAO is associated with favorable clinical outcome.

Keywords: Atrial fibrillation; Left atrial appendage; Mitral regurgitation; Occlusion; Outcomes.

Fig. 1

Flow diagram. Flow diagram for study population selection.

Fig. 2

Kaplan–Meier curves for the primary and thromboembolic outcome. Kaplan–Meier curves for the primary outcome (A) and thromboembolic outcome (B) stratified by left atrial appendage occlusion vs. preservation into two groups in original cohort. Kaplan–Meier curves for the comparison of the primary outcomes and thromboembolic outcome after propensity score matching (C and D).

Fig. 3

Subgroup analysis. Risk of primary outcomes associated with left atrial appendage occlusion or preservation in the subgroups. CAD, coronary artery disease; EF, ejection fraction; MV, mitral valve; LAA, left atrial appendage; AF, atrial fibrillation.