BACKGROUND: The objective of this study was to compare the prognosis of nonselected patients who had an acute myocardial infarction (AMI) during 2 time periods in the thrombolytic era and to describe coronary heart disease (CHD) mortality rates in the community of Göteborg during 1990 to 1995. METHODS: Patients aged <75 years who were hospitalized in the community of Göteborg for AMI during 1990 to 1991 (period 1) and 1995 to 1996 (period 2) were compared in terms of history, treatment for AMI, and outcome. Information on CHD mortality rates in the community of Göteborg was gathered from the National Registry of Deaths. RESULTS: The numbers of patients in the 2 cohorts were 926 and 861, respectively. The incidence rate for AMI per 100,000 inhabitants and year was 200 for period 1 and 183 during period 2. During period 2, there was an increased use of percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, angiotensin-converting enzyme inhibitors, heparin, and intravenous nitroglycerin. On the other hand, there was a decreased use of thrombolytic agents, diuretic agents, digitalis, long-acting nitrates, calcium-channel blockers, and lidocaine. The hospital case-fatality rates were 9.4% during period 1 and 6.0% during period 2 (P =.01). The adjusted risk ratio for period 2 versus period 1 was 0.65, with 95% confidence limits of 0.45 to 0.94. The mortality rate over a period of 3 years was 26.5% during period 1 and 17.8% during period 2 (P <.0001). The adjusted risk ratio for period 2 versus period 1 was 0.67, with 95% confidence limits of 0.54 to 0.82. Among inhabitants aged 30 to 74 years in the community of Göteborg, the CHD mortality rate decreased in 1995 as compared with 1990 (age-adjusted odds ratio 0.79, 95% confidence limits 0.68 to 0.92). CONCLUSIONS: For consecutive patients aged <75 years who were hospitalized for AMI in the community of Göteborg, we found that in the thrombolytic era, major changes in medical and nonmedical treatment still took place associated with a continuing decrease in mortality rates during 3 years of follow-up. A similar reduction of CHD mortality rates was seen in the same age group within the community of Göteborg.