This study compared rates of performance of cardiac procedures in relation to gender, race, and geographic location in patients hospitalized for myocardial infarction. The Atherosclerosis Risk in Communities (ARIC) study provides population data and standardized data collection methods. Hospital records of eligible people aged 35 to 74 years were abstracted in communities of 4 states in the United States: North Carolina, Mississippi, Maryland, and Minnesota. Between January 1987 and December 1991, 5,462 "definite" hospitalized patients with myocardial infarctions were identified. Women treated in nonteaching hospitals were less likely than men to have coronary angiography (odds ratio [OR] 0.7, 95% confidence interval [CI] 0.5 to 1.0), coronary artery bypass graft surgery (CABG) (OR 0.6, 95% CI 0.4 to 0.8), and thrombolytic therapy (OR 0.8, 95% CI 0.6 to 1.0), after controlling for age, race, severity of myocardial infarction, co-morbidity, and geographic area. Findings were similar in teaching hospitals. Blacks in the biracial communities were significantly less likely than whites to have coronary angiography, percutaneous transluminal coronary angioplasty, coronary artery bypass graft surgery, and thrombolytic therapy. After controlling for age, race, severity of myocardial infarction and co-morbidity, no consistent geographic differences were observed, except for Forsyth whites having the highest and Washington County the lowest odds for coronary angiography. Appropriate outcome measures would serve to evaluate the effect, if any, of the differences described on the ARIC population.