Abstract Body (Do not enter title and authors here): Introduction:
Concomitant mitral stenosis (MS) is prevalent in ~10-15% of patients undergoing transcatheter aortic valve replacement (TAVR). There has been conflicting literature on the effect of multivalvular heart disease on TAVR outcomes. TAVR can induce geometric changes in the mitral apparatus, such as annular narrowing and anterior mitral leaflet restriction, which may aggravate MS or unmask previously subclinical disease. Our study aims to investigate the impact of coexisting MS on patients who undergo TAVR.

Methods:
Using the National Inpatient Sample (NIS) from 2020 to 2022, we retrospectively identified patients who had undergone TAVR as a primary procedure. We excluded those with concomitant valvular procedures, prior PPM, urgent procedures, and prior surgical valve repair. Co-existing non-rheumatic MS was identified, and two cohorts were created. Baseline characteristics were compared using t-tests. A multivariable logistic regression model with a 2-sided significance level of 0.05 was used. All baseline characteristics were included in the multivariate adjustment.

Results:
A total of 253,409 weighted hospitalizations for TAVR were identified. 1.05% (2,668) had non-rheumatic MS. The baseline characteristics are given in image-1. Patients with TAVR and concomitant MS were more likely to be female (64.8% vs 42.1%), have underlying HF (80.7% vs 70.6%), and have ESRD (7.3% vs 3.6%). On multivariate analysis, the concomitant MS were more likely to have acute respiratory failure (aOR 1.76, p < 0.001), heart block (aOR 1.81, p < 0.001), and PPM implantation (aOR 1.4, p = 0.005). This cohort was less likely to have a post-procedure systolic/diastolic heart failure exacerbation (aOR 0.58, 95% CI 0.42 to 0.82, p = 0.001). There were no differences in in-hospital mortality. Device embolization was not reported due to the low event rate. The results of the multivariate regression are shown in image-2.

Conclusion:
TAVR is associated with adverse clinical outcomes in patients with MS. However, there is no difference in in-hospital mortality. While the MS + TAVR cohort may have some hemodynamic improvement, as evident by a lower incidence of acute HF, there is an increased risk of PPM placement due to the TAVR valve frame and severe annular calcification affecting the conduction bundles. These findings underscore the importance of preprocedural assessment and risk stratification for patients with combined aortic and mitral valve disease.