Diastology and MitraClip® Outcomes: Multicenter Real-World Evidence Study

<i>Background and Objectives</i>: MitraClip^® (MC) placement has been extensively used as an intervention for mitral transcatheter edge-to-edge repair (mTEER) for functional mitral regurgitation (FMR). The aim of our study is to analyze the association between the pre-procedural echocardiographic parameters of diastolic function (DF) and one-year outcomes after MC placement. <i>Materials and Methods</i>: The study was designed in a retrospective longitudinal cross-sectional format. In total, 224 patients who underwent MC placement between January of 2021 and March of 2024 were included in the study. The Primary Efficacy Endpoint (PEE) was determined by an absence of heart failure hospitalizations requiring Intravenous Diuretics or cardiac-related death in the one-year follow-up period. Multivariate regression analysis was carried out to identify the pre-procedural echocardiographic parameters of DF that had a significant association with a failure to reach the PEE. A two-tailed <i>p</i>-value < 0.05 was used to determine statistical significance. <i>Results</i>: Of the 224 patients included in the study, 85 patients (37.94%) failed to reach the PEE or had worsening symptoms. The mean mitral valve (MV) deceleration time was 176.88 ms (164.14-189.62) in the symptom-worsening group compared to 201.53 ms (186.01-217.07) in the symptom-improvement group. The mean of the E/A ratio (MV peak E velocity/A velocity) was noted to be 2.35 (1.97-2.74) in the symptom-worsening group compared to 1.90 (1.68-2.13) in the symptom-improvement group. After multivariate regression analysis, the E/A ratio was found to have a significant association with a failure to reach PEE: Odds Ratio (OR): 1.61 (1.13-2.29), <i>p</i>-value: 0.008. The area under the curve (AUC) analysis for the E/A ratio was calculated at 0.603 (0.50-0.69) for the symptom-worsening group. <i>Conclusions</i>: Patients that failed to reach the PEE had a lower pre-procedural MV deceleration time of 176.88 ms (164.14-189.62); however, no association was observed between MV deceleration time and a failure to reach the PEE in the multivariate regression analysis. The pre-procedural E/A ratio had a significant association with symptom worsening after multivariate regression analysis: OR: 1.61 (1.13-2.29). The AUC for the E/A ratio in the symptom-worsening group was 0.603, making it a more moderate predictor than random guessing for the failure to reach the PEE.