Utilization of Guideline-Directed Medical Therapies and Transcatheter-Edge-to-Edge Repair in Patients with Significant Secondary Mitral Regurgitation

Introduction: Patients with heart failure with reduced ejection fraction and significant secondary mitral regurgitation (MR) benefit from optimal guideline-directed medical therapies (GDMTs). In those who remain symptomatic despite optimal GDMT, transcatheter edge-to-edge repair (TEER) has been shown to reduce rates of heart failure hospitalization and all-cause mortality. The objective of this study was to evaluate the utilization of GDMT and TEER in patients with significant secondary MR and reduced left ventricular ejection fraction (LVEF) and determine gaps in care delivery. Methods: We conducted a retrospective analysis of all patients in a tertiary care center who had newly diagnosed moderate to severe or severe secondary MR and a LVEF of <50% on echocardiography. Use of medical therapy was evaluated at 3 months after the initial echocardiogram in surviving patients. Optimal GDMT was defined as treatment with 3 or more heart failure therapies. Both univariable and multivariable logistic regression analyses were conducted after excluding patients who experienced early mortality within 3 months. Results: 508 patients were identified from a retrospective chart query. 101 patients (20%) died (median time to death of 56 days) with 63 of these patients experiencing early mortality within 90 days. The remaining 445 patients (age 68 ± 15 years, 55% male, LVEF 29 ± 11%) were analyzed, including 324 with moderate to severe MR and 121 with severe MR. 237 patients (53%) were on optimal GDMT at 3 months after the initial echo. Older patients (OR 0.97, 95% CI 0.95–0.99), patients with coronary artery disease (OR 0.66, 95% CI 0.45–0.96, p = 0.03), cancer (OR 0.55, 95% CI 0.35–0.85, p = 0.01), and chronic kidney disease (CKD) (OR 0.60, 95% CI 0.41–0.87, p = 0.01) were less likely to be on optimal GDMT at 3 months. Age and CKD remained significant variables in the multi-variable analysis. Nine patients (1.8%) underwent TEER with a median time to TEER of 140 days. Conclusion: Patients with significant secondary MR and reduced LVEF have a high mortality. Implementation of optimal GDMT was imperfect, and TEER was rarely utilized. Older patients and those with CKD were less likely to be on optimal GDMT at 3 months. Further study is needed to understand gaps in GDMT implementation and the effective utilization of TEER.