Transcatheter edge-to-edge repair for chronic functional mitral regurgitation in patients with very severe left ventricular dysfunction.

Background: There is scarce data on transcatheter edge-to-edge repair (TEER) for chronic functional mitral regurgitation (FMR) in the setting of very severe left ventricular dysfunction (LVD), defined by a left ventricular ejection fraction (LVEF) of <20%.

Methods: We retrospectively explored periprocedural characteristics and one-year clinical and echocardiographic outcomes of consecutive patients with chronic FMR and very severe LVD who underwent an isolated, first-time TEER. The composite of all-cause mortality or heart failure hospitalizations constituted the primary outcome.

Results: Ninety-six patients (median age 69 [IQR, 55-76] years, 64 (66.7%) males, median LVEF 15 [IQR, 12-17] %) were included. In 47 (49.0%), TEER was performed urgently or in the setting of hemodynamic instability. Almost all procedures (98.0%) were technically successful, leading to ≤moderate MR in 94.7% and 90.7% of cases by 1-month and 1-year, respectively. New York Heart Association class ≤II was maintained in 60.0% of patients. One-year survival and freedom from the primary outcome were 74.0% and 50.0%, respectively. Functional and echocardiographic improvement compared to baseline was independent of procedural urgency, hemodynamic stability, and downstream left ventricular assist device implantation / heart transplantation (n = 12). Mortality was not predicted by COAPT exclusion criteria, nor was the primary outcome discriminated by published risk models.

Conclusion: TEER for chronic FMR is feasible, safe, and efficacious in selected patients with very severe LVD. Preprocedural risk stratification in this population may be optimized.