Survival and readmission among patients with advanced cardiomyopathy undergoing transcatheter edge-to-edge mitral valve repair: Are we applying COAPT findings too broadly?

Objective: Transcathether edge-to-edge mitral valve repair (TEER) has been shown to be an effective treatment for secondary mitral regurgitation (MR). However, the outcomes of TEER in patients with severe cardiomyopathy is less clear. The objective of this study is to determine the outcomes of such patients who underwent TEER at our institution.

Methods: A retrospective review of patients with severe cardiomyopathy, defined as ejection fraction ≤30% or the requirement of inotropic support preoperatively, undergoing TEER for secondary MR at our institution from 11/2016 to 11/2020 was performed. Univariate analysis associating preoperative characteristics with our primary endpoint of 1-year death or orthotopic heart transplant (OHT) was performed. Kaplan-Meier analysis was conducted for the composite outcome of death or OHT, as well as for heart failure-related readmission. Finally, an assessment of changes in MR severity from the preoperative, to immediate postoperative period, to 30-day postoperative period was conducted.

Results: There were 48 patients identified. Median age was 74.5 years (IQR 65.5-79.5), median ejection fraction was 21.5% (IQR 16.0-27.5), and 81.4% of patients had severe or torrential mitral regurgitation preoperatively. The composite endpoint of 1-year mortality or OHT occurred in 15 of 48 patients (31.3%, 14 deaths and 1 OHT). One-year heart failure readmission rate was 47.9%. Mortality or OHT at 2 years occurred in 45.8%.

Conclusion: Patients at extremes of heart failure who underwent TEER had poor outcomes when assessed at 1-year. Our study may suggest that the results of cardiovascular outcomes assessment of the mitraclip percutaneous therapy for heart failure patients with secondary mitral regurgitation may not be applicable to patients with severe cardiomyopathy.