The effects of surgical and transcatheter aortic valve replacement for aortic stenosis on regression and progression of mitral regurgitation -a propensity score matched analysis

Abstract Introduction Significant mitral regurgitation (MR) is frequently encountered in patients with severe aortic stenosis (AS) undergoing Surgical Aortic Valve Replacement (SAVR) or Transcatheter Aortic Valve Replacement (TAVI). This study investigates the differences in MR outcomes between these two procedures. Methods A total of 3,642 patients with AS were followed at our center from 1997 to 2023, consisting of 1,809 who underwent SAVR and 1,833 who received TAVI. Propensity score matching was utilized based on age, gender, and pre-procedural echocardiographic characteristics. Changes in MR were evaluated through echocardiograms taken at baseline and during follow-up, with classification into two groups: grades 0-3 (0 = none to 3 = mild-moderate) and grades 4-6 (4 = moderate to 6 = severe). MR regression was defined as improvement from group 4-6 to group 0-3, and progression was indicated by the reverse crossover. Results Matched cohorts of 539 patients from each group were analyzed (mean age 76.91 years, SD 6.57; 49% female) with similar risk factor distributions. In the SAVR group, 27 patients (5.83%) progressed to grades 4-6, compared to 16 patients (3.58%) in the TAVI group (p=0.109). MR regression (from grades 4-6 at baseline to grades 0-3 at follow-up) occurred in 25 patients (43.86%) in the SAVR group and 33 patients (66%) in the TAVI group (p=0.0218). Conclusion Both SAVR and TAVI show minimal effects on MR progression. However, TAVI patients with moderate or greater MR at baseline demonstrate a significantly higher rate of MR regression compared to those undergoing SAVR.