Abstract 14909: The Sweet Spot - Achieving Less Mitral Regurgitation at the Cost of Increasing Mitral Gradients Improves Short-term Outcomes in Percutaneous Mitral Valve Repair

Abstract

Background: In the last year, percutaneous mitral valve repair (PMVR) using the MitraClip system (Evalve Inc., Menlo Park, California) has established itself as a proven treatment option for patients with inoperable mitral regurgitation (MR). However, reduction of MR usually comes at the expense of forward flow and mean mitral gradients (MMG). Finding the ideal balance of reduction of MR grade and acceptable MMG carries significant clinical implications. The purpose of this study was to compare short-term outcomes in patients with less than moderate MR but elevated MMG to patients with at least moderate MR. Methods: This was a retrospective, observational study from 2014-2019 of 128 patients who underwent PMVR at our institution. Patients were separated into cohorts depending on their post-PMVR MR grade and MMG. Cohort 1 included patients with the best possible result post-PMVR, less than moderate MR and a MMG <5mmHg. Cohort 2 included patients less than moderate MR but a MMG >5mmHg post-PMVR. Cohort 3 included patients with at least moderate MR post-PMVR. Our primary outcome of interest was a composite of inpatient death and 30-day readmission. Results: Cohort 1 included 30 patients who had less than moderate MR and a MMG <5mmHg post-PMVR. This cohort had the primary composite endpoint in 10.0% of patients. Cohort 2 included 33 patients who had less than moderate MR but a MMG >5mmHg. Cohort 3 included 65 patients who had more than moderate MR post-PMVR. We found that our primary composite endpoint occurred more frequently in patients who had at least moderate residual MR (cohort 3) (9.1% vs. 27.7%, p=0.0438). Patients with less than moderate MR post-PMVR despite a MMG >5mmHg were 3.8 times less likely to have inpatient death or a 30-day readmission when compared to patients with at least moderate MR post-PMVR (CI 0.071, 0.963). Conclusions: Our study suggests that achieving a goal of less than moderate MR despite modest increases in MMG can result in better short-term outcomes (inpatient death + 30-day readmission) when compared to patients who are left with at least moderate MR post-PMVR.