The evolution of concomitant mitral regurgitation in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement: a prospective multi-center China-DVD2 cohort study.

Background: Severe aortic stenosis (AS) often coexists with mitral regurgitation (MR). This study evaluated the significant evolution of MR in patients undergoing transcatheter aortic valve replacement (TAVR) for AS.

Methods: This multi-center China Degenerative Valve Disease II Cohort (China-DVD2) Study enrolled patients undergoing TAVR for AS from January 2020 to October 2023. MR severity was assessed at baseline and 12 months post-TAVR. Composite endpoints included all-cause death, heart failure rehospitalization, myocardial infarction, and angina.

Results: Among 424 enrolled patients, 130 (31%) had significant MR at baseline. At 12 months, MR improved in 56 (70%) of 80 patients with follow-up, and greater improvement in left ventricular ejection fraction (LVEF)was associated with MR improvement [odds ratios (OR): 0.97, 95% 95% confidence interval (CI): 0.95-1.00, p = 0.04)]. Patients with MR improvement showed significant New York Heart Association (NYHA) functional class improvement at 12-month follow-up. No survival benefit disparity was observed between patients with and without significant baseline MR, but a trend toward lower composite endpoint rate (12.5% vs. 20.8%, log-rank p = 0.49) was observed in patients with MR improvement. Older age [hazard ratios (HR): 1.12, 95% CI: 1.01-1.24, p = 0.04)] and higher systolic pulmonary arterial pressure (SPAP) (HR: 1.05, 95% CI: 1.00-1.09, p = 0.04) were linked to worse outcomes.

Conclusions: Most patients with significant MR experienced improvement of NYHA class and MR post TAVR. Baseline significant MR was not linked to worse outcomes, but MR improvement showed a trend toward better prognosis. Older age and higher SPAP predicted worse outcomes.