We compared medical care and mortality through 1-year of hospitalized acute myocardial infarction (AMI) patients in 2 large metropolitan areas in the United States and Sweden. All hospitalized AMI discharges (International Classification of Diseases, 9th revision [ICD9] codes 410) occurring among 30 to 74-year-old residents of the Minneapolis-St. Paul metropolitan area in 1990 and Goteborg, Sweden, in 1990 to 1991 were identified and their medical records examined. There were dramatic differences in medical care during the index hospitalization of AMI patients between Minneapolis-St. Paul and Goteborg. Use of thrombolytic therapy, coronary angioplasty, bypass surgery, calcium antagonists and lidocaine was more common in Minneapolis, St. Paul; β blockers were more frequently used in Goteborg, and aspirin use was similar. Despite these large differences, neither 28-day nor 1-year mortality of hospitalized AMI patients differed significantly. The marked differences found in the early treatment of AMI between Minneapolis-St. Paul and Goteborg, combined with the negligible differences observed in short- and long-term mortality, raise questions about the most effective and efficient allocation of medical resources.