The authors compare distribution of genotype frequencies and alleles of I/D of ACE gene polymorphism in patients with various forms of ischemic heart disease (IHD): with acute myocardial infarction (MI), stable effort angina (functional class II-III); in patients with postinfarction cardiosclerosis (PICS). A relationship was found between I/D polymorphism and acute MI. Frequency of DD genotype in MI patients was 0.57, in controls--0.21, p < 0.0001, RR = 4.9. The DD genotype may serve a marker of hereditary predisposition to MI. Genotype DD frequency in the group with acute MI was higher than that with PICS. In acute MI frequency of allele D was 0.76, in PICS--0.51, p < 0.0005. It is suggested that low frequency of genotype DD in the PICS group results from higher lethality of patients with DD genotype in the nearest rehabilitation period. Patients with repeated MI have a significantly higher frequency of genotype DD and complications after MI. Thus, there is a relationship between insertion-deletion polymorphism of ACE gene and myocardial infarction. Deletion DD genotype raises the risk to develop MI and probability of life-threatening complications and repeated MI.