Acute Myocardial Infarction without Warning: Clinical Characteristics and Significance of Preinf arction Angina

Abstract

We investigated the clinical characteristics of acute myocardial infarction (AMI) not preceded by angina in 256 patients with first AMIs. Complications, including sustained ventricular tachycardia or ventricular fibrillation, pump failure and cardiac rupture, were more frequent in patients with AMI not preceded by angina (group 1, n = 92) than those preceded by angina (group 2, n = 164). The in-hospital mortality rate was higher in group 1 than in group 2. Poor preexisting collateral channels or lack of ischemic preconditioning may be responsible for the poorer outcome in group 1 patients.