INFLUENCE OF PRIOR ACE-INHIBITOR THERAPY ON MORBIDITY AND MORTALITY FOLLOWING ACUTE MYOCARDIAL-INFARCTION

BACKGROUND: Angiotensin-converting enzyme inhibitor (ACE-I) therapy re duces complications of acute myocardial infarction OW) even when the t herapy is started very early after an acute event. This study sought t o determine whether administration of ACE-I therapy prior to acute MI is related to subsequent patient morbidity and mortality. METHODS: Cha rt review of 318 consecutive patients admitted between September 1995 and December 1996 with a diagnosis of acute MI. Outcome data were comp ared between patient groups receiving ACE-I therapy prior to infarctio n and those who were not. RESULTS: Sixty-four patients (20%) were rece iving prior ACE-I therapy. They experienced smaller MIs, as determined by peak creatine kinase elevation (1066 +/- 134 vs. 1510 +/- 95 lU; p < 0.05), and fewer Q-wave infarctions (p < 0.05) than did patients wh o were not receiving prior treatment. The severity of coronary artery disease, defined by an angiographic score, was similar for the two gro ups. Mortality rates, including patients resuscitated from ventricular fibrillation, were similar within the first 72 hours of admission (3% vs. 2%; p = NS), but patients receiving prior ACE-I therapy showed a greater long-term in-hospital mortality rate (14% vs. 5%; p < 0.05) re lated to more heart failure deaths. Multivariate logistic regression a nalysis identified age, treatment with digoxin prior to acute MI, and left ventricular ejection fraction after infarction, but not ACE-I the rapy taken prior to infarction, as significant independent predictors of mortality and combined morbidity and mortality. CONCLUSIONS: In a g roup of patients experiencing an acute MI, those receiving prior ACE-I therapy were more likely to sustain fewer transmural MIs and smaller infarcts. Chronic ACE-I therapy may have cardioprotective effects duri ng acute myocardial ischemia.