Left and Right Ventricular Hemodynamic Response After Transcatheter Mitral Valve Replacement

Background

Transcatheter mitral valve replacement (TMVR) represents a novel treatment option for patients with mitral regurgitation (MR), but little is known about the hemodynamic impact of MR elimination following TMVR. We sought to investigate the hemodynamic impact of TMVR on left ventricular (LV) and right ventricular (RV) function using noninvasive pressure-volume loops.

Methods

All consecutive patients undergoing TMVR with dedicated devices between May 2016 and August 2022 were enrolled. The end-diastolic and end-systolic pressure-volume relationships were estimated from 26 patients using single-beat echocardiographic measurements at baseline and after TMVR at discharge. RV function was assessed by RV-pulmonary artery (PA) coupling and RV fractional area change. One-year follow-up was available for 19 patients. The prognostic impact of calculated end-diastolic volume at an end-diastolic pressure of 20 mmHg (VPed20) reduction was assessed by Cox regression.

Results

A total of 26 patients (77.0 years [interquartile range 73.9-80.1], N = 17 [65.4%] male) with successful TMVR were included (secondary MR [N = 21, 80.8%]; median LV ejection fraction was 37.0% [interquartile range 30.7-50.7]). At discharge, a decrease in VPed20 (p < 0.001) indicating leftward shift of end-diastolic pressure-volume relationship, and an increase of the end-systolic elastance slope (p = 0.007) were observed after TMVR. No changes were observed for RV-PA coupling (p = 0.19) and RV fractional area change (p = 0.22). At 1-year follow-up, LV contractility (end-systolic elastance) and RV-PA coupling remained stable. Vped20 reduction at discharge was significantly associated with 1-year all-cause mortality or heart failure hospitalization (hazard ratio 0.16, 95% CI 0.04-0.71, p = 0.016).

Conclusions

Noninvasive assessment of pressure-volume loops demonstrated early LV reverse remodeling and improved LV contractility, while RV performance was preserved. These results indicate the potential prognostic impact of complete MR elimination after TMVR.