Correlates and prognostic implications of LVEF reduction after transcatheter edge-to-edge repair for primary mitral regurgitation.

Abstract

To explore the characteristics and outcomes of patients undergoing transcatheter edge-to-edge repair (TEER) for primary mitral regurgitation (MR) according to the presence of left ventricular ejection fraction (LVEF) reduction post-procedure. We retrospectively analysed 317 individuals [median age 83 (interquartile range, 75-88) years, 197 (62.1%) males] treated with an isolated, first-time TEER that was concluded by a successful clip deployment. Stratified by LVEF change at 1-month compared with baseline, the cohort was evaluated for residual MR and heart failure (HF) indices up to 1-year, as well as all-cause mortality and HF hospitalizations at 2-years. Overall, 212 (66.9%) patients displayed LVEF reduction, which was mainly driven by lowered total stroke volume and diffuse hypocontractility. While post-procedural MR, transmitral mean pressure gradient, and functional status were comparable in the two study groups, patients with LVEF reduction exhibited a greater decline in filling pressures intra-procedurally; left ventricular mass index, pulmonary arterial systolic pressure, and serum natriuretic peptide level at 1-month; and walking limitation at 1-year. Also, by 2 years, they were less likely to die (13.3% vs. 5.7%, P = 0.019), be readmitted for HF (17.1% vs. 9.0%, P = 0.033), and experience either of the two (23.8% vs. 12.7%, P = 0.012). Lastly, LVEF reduction was the only 1-month echocardiographic parameter to independently confer an attenuated risk for the composite of deaths or HF hospitalizations (HR 0.28, 95% CI 0.10-0.78, P = 0.016). LVEF reduction at 1-month post-TEER for primary MR is associated with better clinical outcomes, possibly reflecting a more pronounced unloading effect of the procedure.