Mitral insufficiency and morbidity and mortality in left ventricular dysfunction

Background: Mitral insufficiency is known to occur in a substantial proportion of patients with heart failure. Its relationship with morbidity and mortality is poorly described. Methods: The mortality and hospitalization for heart failure were retrospectively examined in patients who underwent baseline echocardiography in the Studies Of Left Ventricular Dysfunction (SOLVD) treatment and prevention trials. The presence and grade of mitral insufficiency was assessed, and patients with and without mitral insufficiency were compared. Results: Patients with left ventricular dysfunction and mitral insufficiency had greater than twofold increased risk of death or admission for heart failure over two years (RR 2.38, 95% CI 1.43 to 3.97). This excess risk persisted after adjustment for the severity of heart failure, etiology and differences in treatment (RR 1.82, 95% CI 1.04 to 3.17; P=0.04). The presence of moderate mitral insufficiency versus no insufficiency was associated with even greater independent risk (RR 2.20, 95% CI 1.01 to 4.80; P=0.05). Results were consistent with binary and ordinal analysis of mitral insufficiency. Conclusion: The presence of mitral insufficiency in patients with left ventricular dysfunction is independently associated with adverse outcomes, including death and hospitalization for heart failure. This has potentially important clinical implications for the assessment and management of patients with heart failure.