This is a case series analysis undertaken to evaluate the importance of acute myocardial infarction (AMI) as a cause of admission at the Tikur Anbassa medical intensive care unit (MICU) and the trend of that importance over a decade (1988-1997). Clinical presentations and the frequencies of major coronary risk factors in the individual patient were also assessed for the later half of the decade (1993-1997). In the decade under study 2313 patients were admitted to MICU according to its register. Overall AMI was the third commonest cause of admission and accounted for 8.8% (N = 203) of all MICU cases. AMI annual admissions increased consistently over the years. Of the 122 AMI admissions during the second half of the decade, 92 charts were available for detailed analysis. 86% (79/92) fulfilled the stated criteria for the diagnosis. The mean age of these patients was 55.1 +/- 13.0 years. Males constituted 82% of all AMI cases. Eighty seven percent (69/79) of the cases were first admissions with the diagnosis of AMI. Ninety-four percent (74/79) of them were brought to the emergency room due to chest discomfort and 20% were in frank pulmonary oedema. Nineteen percent died in hospital. 81% and 34% of the patients had one or more and two or more major coronary risk factors excluding age and gender respectively. Raised total cholesterol and hypertension were commonest risk factors being reported in 69% and 47% of AMI patients respectively. In conclusion, this study has demonstrated that AMI is indeed on the rise at least at Tikur Anbassa Teaching Hospital, and possibly at other health institutions. The conventional coronary risk factors seem to operate in the Ethiopian series as well. The study highlights the need for coronary risk factors surveys at least in the susceptible population group to assess the gravity of the problem.