Residual Moderate Mitral Regurgitation Linked to Worse Heart Failure Outcomes

Researchers analyzed 2,468 ambulatory patients with heart failure who had echocardiography at baseline and after 12 months of optimized guideline-directed medical therapy. Mean age was 66.2 years, 70.6% were male, and mean baseline left ventricular ejection fraction was 36.1%. The primary outcome was all-cause death or first heart failure hospitalization; secondary outcomes included all-cause mortality and recurrent hospitalizations.

At 12 months, 15.6% had moderate MR, 3.9% had severe MR, and 80.5% had no or mild MR. Over a median 6.9 years, 1,240 patients experienced the primary outcome. Compared with no or mild MR, moderate MR was associated with a higher risk of the composite outcome (adjusted hazard ratio 1.69, 95% CI 1.47–1.95) and all-cause mortality (HR 1.54, 95% CI 1.32–1.79). Recurrent hospitalization rates were also higher (incidence rate ratio 2.17, 95% CI 1.81–2.60). Heart failure hospitalization rates were 20.0 per 100 person-years with moderate MR versus 9.03 with no or mild MR.

These findings identify residual moderate MR after medical therapy as a marker of poorer prognosis in this population. The observational analysis establishes an association, not that treating MR improves outcomes; the supplied abstract does not report treatment comparisons.