Systematic review and meta-analysis of left atrial appendage closure’s impact on early- and long-term mortality and stroke.

Objective Left atrial appendage closure (LAAC) concomitant to heart surgery in patients with underlying atrial fibrillation (AF) has gained attention because of long-term reduction of thromboembolic complications. As of mortality benefits in the setting of non-AF, data from both observational studies and randomized controlled trials (RCTs) are conflicting. Methods On-line databases were screened for studies comparing LAAC vs no-LAAC concomitant to other heart surgery. Endpoints assessed were all-cause mortality and stroke at early and longest available follow-up. Subgroup analyses stratified on pre-op AF were performed. Risk ratios (RR) with 95% Confidence Intervals (CIs) served as primary statistics. Results Electronic search yielded 25 studies (N=660,158 patients). There was no difference between LAAC and no-LAAC in terms of early mortality. In the overall population analysis, LAAC reduced long-term mortality (RR 0.86, 95%CIs 0.74-1.00, P=0.05, I2=88%), reduced early stroke risk by 19% (RR 0.81, 95%CIs 0.72-0.93, P=0.002, I2=57%) and late stroke risk by 13% (RR 0.87, 95%CIs 0.84-0.90, P<0.001, I2=58%). Subgroup analysis showed lower mortality (RR 0.85, 95%CIs 0.72-1.01, P=0.06, I2=91%), short- and long-term stroke risk reduction only in patients with pre-op AF (RR 0.81, 95%CIs 0.71-0.93, P=0.003, I2=71% and RR 0.87, 95%CIs 0.84-0.91, P<0.001, I2=70%, respectively). No benefit of LAAC in patients without AF was found. Conclusions Concomitant LAAC was associated with reduced stroke rates at early- and long-term and possibly reduced all-cause mortality at long-term but the benefits were limited to patients with preoperative AF. There is not enough evidence to support routine concomitant LAAC in non-AF setting.