Validation of the COAPT risk score in Polish patients undergoing transcatheter edge-to-edge repair of severe, functional mitral regurgitation: a multicenter, observational study.

Background: The COAPT risk score, developed based on the COAPT trial, is a tool to predict the risk of death or hospitalization for heart failure (HFH) within two years after transcatheter edge-to-edge repair (TEER) of mitral regurgitation using a MitraClip device. We aimed to validate the Score in a Polish population.

Methods: Patients with severe mitral regurgitation who underwent TEER with MitraClip at three cardiology centers in Poland between November 2015 and February 2023 were included. Patients were divided into two groups based on the COAPT trail criteria: COAPT eligible and COAPT non-eligible. Clinical data were collected from medical records and the COAPT risk score was calculated for each patient. Outcomes were collected during the two-year follow-up period. The primary endpoint was a composite of all-cause mortality and HFH at two-year follow-up and evaluated in the overall cohort and separately for COAPT-eligible and -non-eligible patients.

Results: A total of 225 patients were included in the study: 134 COAPT eligible (60%) and 91 COAPT non-eligible (40%). Higher COAPT risk score was associated with increased risk of primary endpoint in the overall population and in COAPT-eligible patients. The score demonstrated moderate discrimination (area under curve [AUC] = 0.581) and poor calibration (Hosmer-Lemeshow [HL] p = 0.085) in the overall population, whereas it showed moderate discrimination (AUC = 0.600) and good calibration (HL p = 0.308) in COAPT-eligible patients.

Conclusions: In Polish patients fulfilling COAPT criteria, the COAPT risk score has moderate predictive value for post-procedural outcomes. In COAPT non-eligible patients, novel tools are required to predict outcomes.