The purpose of the study was to determine the conditions under which hyperinsulinemia (HI) is manifested in patients with coronary heart disease (CHD). Such factors as clinical manifestations of CHD, coronary atherosclerosis severity, and myocardial dysfunction severity, were taken into account. The subjects were 201 men aged 47.3 +/- 1.5 years, suffering from CHD. The condition of coronary and intracardial hemodynamics, as well as insulin and glucose blood levels were compared, and correlations between these parameters and the stage, severity, and type of coronary insufficiency (CI) were studied. Two clinical groups were formed. Group I consisted of 74 CHD patients with no myocardial infarction (MI) background; group II consisted of 127 patients with postinfarction myocardial dysfunction (PIMD). Subgroups of patients with acute coronary syndrome (ACS), including subjects with newly developed stenocardia (NDS) and subjects with progressive stenocardia (PS), were formed. In all cases of ACS the basal insulin levels were increased: by 197.4% in patients with NDS, by 167% in patients with PS and no MI background, and by 114,3% in PIMD subgroup (p < 0.05). Some of the ACS patients developed a short-term moderate hyperglycemia (up to 7 mmol/l), that was coped with after 1 to 3 days of antischemic therapy and protective therapeutic regimen. The extent of HI correlated with the severity of coronary atherosclerosis as well as the degree of intracardial and coronary hemodynamic disturbances, and myocardial dysfunction. The results show that HI in CHD patients manifests itself under the condition of CI progression and may be used as a diagnostic marker of residual myocardial ischemia; the degree of HI at different stages of the disease is determined by the severity of CI and myocardial insufficiency, as well as, probably, by the organism's compensatory capacity.