We assessed patients' health-related quality of life after myocardial infarction and identified related variables. Clinical data were obtained retrospectively from medical records of consecutive patients admitted to a Midwestern university-affiliated medical center with diagnosis of myocardial infarction from July 1999-July 2000. Telephone interviews 7 months after discharge were made to administer the Short Form-12 (SF-12) and obtain patient, disease, drug, and intervention data. Complete information was obtained from 200 patients (mean age 63.4 +/- 13.1 yrs, 68% men). The mean Physical Component Summary (PCS)-12 score was 40.6 +/- 12.0, and the mean Mental Component Summary (MCS)-12 score was 52.1 +/- 10.0. Based on univariate analyses, low PCS-12 scores were associated with women; non-Q-wave infarctions; greater number of illnesses; history of myocardial infarction, chronic heart failure (CHF), transient ischemic attack (TIA), renal disease, peripheral vascular disease, or percutaneous coronary intervention (PCI); rehospitalization during the interim period; and unscheduled PCI since index myocardial infarction. Low MCS-12 scores were associated with age below 65 years, low overall self-reported drug therapy compliance, low self-reported compliance with angiotensin-converting enzyme inhibitor and lipid-lowering therapy, no history of coronary artery bypass graft, and no stress test since index myocardial infarction. A multivariate regression model for PCS-12 kept the following variables: greater number of illnesses, history of CHF or TIA, and rehospitalization since index myocardial infarction. The MCS-12 model contained age below 65 years, low overall compliance, and low compliance with lipid-lowering therapy. Further work is necessary to determine noncardiovascular predictors of quality of life and whether interventions for these patients will result in improved quality of life.