Prediction of Death or HF Hospitalization in Patients With Severe FMR: The COAPT Risk Score

There are limited data on the predictors of death or heart failure hospitalization (HFH) in patients with heart failure (HF) with functional mitral regurgitation (FMR).

The aim of this study was to develop a predictive risk score using the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) trial database.

In COAPT, 614 symptomatic patients with HF and moderate to severe or severe FMR were randomized to MitraClip implantation plus guideline-directed medical therapy (GDMT) or GDMT alone. A risk score for the 2-year rate of death or HFH was generated from Cox proportional hazards models. The predictive value of the model was assessed using the area under the curve of receiver-operating characteristic plots. Kaplan-Meier curves were generated to estimate the proportion of patients experiencing death or HFH across quartiles of risk.

During 2-year follow-up, 201 patients (64.4%) in the GDMT-alone group and 133 patients (44.0%) in the MitraClip group experienced death or HFH (P < 0.001). A risk score containing 4 clinical variables (New York Heart Association functional class, chronic obstructive pulmonary disease, atrial fibrillation or flutter, and chronic kidney disease) and 4 echocardiographic variables (left ventricular ejection fraction, left ventricular end-systolic dimension, right ventricular systolic pressure, and tricuspid regurgitation) in addition to MitraClip treatment was generated. The area under the curve of the risk score model was 0.74, and excellent calibration was present. The relative benefit of MitraClip therapy in reducing the 2-year hazard of death or HFH was consistent across the range of baseline risk.

A simple risk score of clinical, echocardiographic, and treatment variables may provide useful prognostication in patients with HF and severe FMR.