OBJECTIVES: To describe the differences in characteristics and outcome between two consecutive series of patients admitted to hospital with chest pain in a 20-year perspective. Particular emphasis is placed on changes in outcome in relation to the initial electrocardiogram (ECG). SUBJECTS: In the two periods, 1986-1987 and 2008, all patients with chest pain admitted to the study hospitals in Gothenburg, Sweden, were included. RESULTS: Five thousand and sixteen patients were registered in a period of 21 months in 1986-1987 and 2287 patients were registered during 3 months in 2008. In a comparison of the two time periods, the age of chest pain patients was not significantly different (mean age 60.1 ± 17.8 years in 1986-1987 and 59.8 ± 19.1 years in 2008, p=0.50). There was a lower prevalence of previous angina pectoris, congestive heart failure and current smoking in the second period, whereas a history of acute myocardial infarction, hypertension and diabetes mellitus had become more prevalent. The use of cardio-protective drugs increased and ECG changes indicating acute myocardial ischemia on admission to hospital decreased. Length of hospitalisation was reduced from a median of 5 days to 3 days (p<0.0001). A significant decrease in 30-day and 1-year mortality was found (3.8% in 1986-1987 vs 2.0% in 2008 and 9.9% vs 6.3% respectively, p<0.0001 for both comparisons). CONCLUSIONS: During a period of 20 years, the characteristics and outcome of patients admitted to hospital with chest pain changed. The most important changes were a lower prevalence of ECG signs indicating acute myocardial ischemia on admission, shorter hospitalisation time and a lower 30-day and 1-year mortality.