Ischemic Mitral Regurgitation and Non-ST-Segment Elevation Acute Myocardial Infarction: Long-Term Prognosis

Abstract

Ischemic mitral regurgitation (MR) is a common complication of acute myocardial infarction and has a negative impact on prognosis. However, few studies have been carried out on MR after non-ST-segment elevation acute myocardial infarction (NSTEMI). Our objective was to investigate the incidence, clinical predictors and long-term prognostic implications of MR in patients with NSTEMI. The prospective study included 237 consecutive patients who were discharged in functional class I or II after a first NSTEMI. Each underwent echocardiography during the first week of admission, and patients were followed up clinically for a median of 1011 days. The incidence of readmission for heart failure, unstable angina, reinfarction, death or all combined (i.e. the combined event or major adverse cardiac event [MACE]) was recorded. The patients' mean age was 66+/-13 years and 74% were male. The incidence of MR was 40% (grade I in 71 patients, grade II in 15, grade III in 6, and grade IV in 3). Age, diabetes mellitus, multivessel disease and MR (HR=2.17; 95% confidence interval 1.30-3.64; P=.003) were all independently associated with a poor long-term prognosis, in terms of MACEs. Even the milder grades of MR were associated with more events. In our milieu, MR frequently occurs after NSTEMI. Its presence together with other unfavorable factors implies a poor long-term prognosis. This is also true for milder grades of MR. Consequently, MR should be fully assessed and followed-up after NSTEMI in all patients.