CLINICAL AND ECHOCARDIOGRAPHIC PARAMETERS ASSOCIATED WITH OUTCOMES IN PATIENTS WITH MODERATE FUNCTIONAL MITRAL REGURGITATION

Background: Significant functional mitral regurgitation (FMR) is associated with worse prognosis. However, data for moderate FMR alone is lacking. We explored clinical and echocardiographic parameters associated with worse outcome in these patients.
Methods: Patients with moderate FMR (n=1061, mean age 69 ±11years, 59% male) were retrospectively included and classified as atrial FMR (AFMR, n=352), if mitral annulus dilatation and normal left ventricle ejection fraction (LVEF) and dimensions, or as ventricular FMR (vFMR, n=709) in case of impaired LVEF and/or LV remodeling. vFMR was subdivided based on LVEF ≥40% (n=329) and <40% (n=380).The primary endpoint was all-cause mortality and the secondary endpoint was all-cause mortality and heart failure.
Results: Overall, 19% had NYHA class III-IV and 52% had atrial fibrillation. During a median follow-up of 82 (IQR 55-115) months, 397 (37%) died and 539 (51%) patients had heart failure or death. A significant difference for both endpoints was seen across the 3 groups (p<0.001, Fig). In multivariable analysis, as compared to aFMR, vFMR LVEF≥40% (HR: 1.528; CI 1.108-2.106, p=0.010) and vFMR LVEF <40% (HR: 1.960; CI 1.434-2.679, p<0.001) were independently associated with both outcomes together (as detrimental) with NYHA class III-IV, age, male sex, diabetes, COPD, left atrial volume index and lower right ventricle pulmonary artery coupling index.
Conclusion: In moderate MR, symptoms and etiology of FMR have a significant association with outcome.