Prognostic significance of echocardiographically defined mitral regurgitation early after acute myocardial infarction

Background: There are limited data regarding the clinical correlates and prognostic significance of echocardiographically defined mitral regurgitation (MR) early after acute myocardial infarction (MI). The current study addressed these issues. Methods: Seven hundred thirty-seven patients with acute MI who underwent transthoracic echocardiography with assessment of MR during their index admission were identified. Patients were followed up a median of 19 months later. The study end point was all-cause mortality. Results: The prevalence of MR increased with age. It was more common in women, in patients with non-ST-elevation MI, and in those with a history of diabetes, hypertension, prior MI, or previous revascularization. Patients with MR had worse left ventricular (LV) systolic function, more LV dilatation, and more clinical evidence of LV failure. Patients with moderate or severe MR had worse survival than those with no or mild MR (hazard ratio 2.3, 95% CI 1.6-3.2, P < .0001). Even mild MR predicted a higher mortality when compared with no MR (hazard ratio 1.7, 95% CI 1.2-2.4, P = .004). Mild or moderate MR was not independently predictive of outcome, although, in multivariable analyses, a trend toward worse survival was maintained in patients with severe MR. Conclusions: Mitral regurgitation, identified by echocardiography, early after acute MI predicts poorer survival after acute MI. However, if mild or moderate, it is not an independent prognostic indicator.