Evaluation of functional mitral regurgitation profile in a real-world cohort of heart failure patients and the referral rate of these patients

Abstract

Abstract Introduction Patients with heart failure and reduced ejection fraction (HFrEF) frequently have significant functional mitral regurgitation (FMR), which carries important prognostic impact. Randomized clinical trials on transcatheter mitral-valve repair have shown conflicting results, and their representativeness in real-world populations are unclear. Purpose This real-world study sought to identify the proportion of patients who would be eligible for mitral valve intervention and describe the current referral patterns at an academic center. Methods We conducted a single center cross-sectional study enrolling consecutive patients with HFrEF and FMR under guideline directed medical therapy from January 2010 to December 2018. Moderate FMR was defined as the presence of an effective regurgitant orifice area (EROA) of ≥20mm2 or a regurgitant volume (Regvol) of ≥30mL/beat, according to American Society of Echocardiography guidelines. Demographic, clinical, echocardiographic and treatment data were assessed. Main MITRA-FR and COAPT Trial eligibility criteria (NYHA class, left ventricular ejection fraction (LVEF), left ventricle end-systolic diameter, pulmonary artery systolic pressure, and right ventricle dysfunction) were applied according to trial protocols. Patterns of referral for mitral valve intervention were assessed by pre-procedural transesophageal echocardiography for mitral regurgitation evaluation. Results A total of 175 patients with at least moderate FMR were included in the analysis (mean age 70±12 years, 80% male, mean LVEF 32% ±9). After applying the main eligibility criteria for each study, 73.7% (n=129) of patients would have been enrolled in MITRA-FR trial, whereas only 27.4% (n=48) patients would have met criteria for COAPT trial (Figure 1). Patients with MITRA-FR profile had a mean EROA 25±8 mm2; mean Regvol 36±9 mL/beat; mean LVEDV 205±72 mL; EROA/LVEDV ratio 0.13±0.04. “COAPT-like” patients had a mean EROA 33±10 mm2; mean Regvol 48±13 mL/beat; mean LVEDV 203±65 mL; mean EROA/LVEDV ratio 0.17±0.05. Only 13.1% (n=23) were referred for transesophageal echocardiography in order to establish the criteria of feasibility for mitral intervention. A total of 16 patients (9.1%) were submitted to mitral valve intervention during follow-up. Conclusion In a real-world population of HFrEF patients with significant FMR, more than one fourth of patients had a “COAPT-like” profile and could have benefited from percutaneous mitral valve intervention. The referral rate for evaluation for a potential intervention was low, which precludes patients from benefiting from this type of treatment. Funding Acknowledgement Type of funding sources: None.