Perioperative Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement with Concomitant Mitral Regurgitation: A Meta-Analysis

Transcatheter aortic valve replacement (TAVR) is widely performed in high-risk patients with severe aortic stenosis. However, the effects of baseline concomitant mitral regurgitation (MR) on perioperative outcomes remain unclear. This study evaluated the impact of concomitant MR severity on short-term TAVR outcomes. A systematic search of 6 electronic databases was conducted. Studies that stratified patients based on MR severity (MR ≥2 vs. <2 or MR ≥3 vs. <3) and reported perioperative outcomes, including short-term mortality, in-hospital mortality, acute kidney injury (AKI), pacemaker implantation, bleeding, vascular complications, and MR improvement (up to 1 week and 1 month) were eligible. Data from 26 studies (32,453 patients) demonstrated that patients with baseline moderate-to-severe MR (MR ≥2) had a 49% (95% confidence interval (CI), 1.32-1.70) increased risk of short-term mortality, a 41% (95% CI, 1.22-1.63) higher risk of in-hospital mortality, and a 38% (95% CI, 1.17-1.62) higher risk of AKI than those with none-to-mild MR (MR<2). Patients with an MR ≥3 had an even greater 72% (95% CI, 1.37-2.16) increase in short-term mortality. No significant differences were observed in pacemaker implantation, bleeding, or vascular complications between groups. Additionally, after TAVR, MR improved in 36% of patients by at least 1 grade within 1 week, increasing to 44% by 1 month. In TAVR patients, MR ≥2 was associated with significantly higher early mortality and AKI risk, underscoring the need for a comprehensive perioperative risk assessment. Future studies should examine the differential impact of functional and degenerative MR.