Outcome of Patients Sustaining Acute Ischemic Mitral Regurgitation during Myocardial Infarction

Abstract

▪ Objective: To describe outcomes of patients sustaining an acute myocardial infarction complicated by mitral regurgitation managed with contemporary reperfusion therapies.

▪ Design: Inception cohort case study. Long-term follow-up was obtained in 99% of all patients.

▪ Setting: University referral center.

▪ Patients: A series of 1480 consecutive patients presenting between April 1986 and March 1989 who had emergency cardiac catheterization within 6 hours of infarction. Fifty patients were found to have moderately severe or severe mitral regurgitation.

▪ Outcome Measures: Mortality; follow-up cardiac catheterization in patients with regurgitation.

▪ Results: Acute ischemic moderately severe to severe (3 + or 4 +) mitral regurgitation was associated with a mortality of 24% at 30 days (95% Cl, 12% to 36%), 42% at 6 months (Cl, 28% to 56%), and 52% at 1 year (Cl, 38% to 66%); multivariable analysis identified 3 + or 4 + mitral regurgitation as a possible independent predictor of mortality (P = 0.06). Patients with mitral regurgitation tended to be female, older, and to have cerebrovascular disease, diabetes, and preexisting symptomatic coronary artery disease. A physical examination did not identify 50% of patients with moderately severe to severe regurgitation. Acute reperfusion with thrombolysis or angioplasty did not reliably reverse valvular incompetence. In this observational study, the greatest in-hospital and 1-year mortalities were seen in patients reperfused with emergency balloon angioplasty, whereas patients managed medically or with coronary bypass surgery had lower mortalities.

▪ Conclusions: Moderately severe to severe (3 + or 4 +) mitral regurgitation complicating acute myocardial infarction portends a grave prognosis. Acute reperfusion does not reduce mortality to levels experienced by patients with lesser degrees of mitral regurgitation nor does it reliably restore valvular competence.