In Coronary Care Unit and Intensive Care Unit, Zagreb University Hospital Centre, 403 patients were hospitalized for acute myocardial infarction (AMI) in the year 2005. Majority (288) patients presented with ST-segment elevation myocardial infarction (STEMI) and 115 patients with acute myocardial infarction without ST-segment elevation (NSTEMI). In-hospital mortality of STEMI patients was 13.9% vs. 9.6% of NSTEMI group of patients. In STEMI group 202 patients underwent urgent percutaneous coronary intervention (PCI), and 86 patients in STEMI group received conservative therapy. In-hospital mortality of patients treated with primary PCI was 5.9% vs. 29.1% in the group treated conservatively. The main reason for conservative therapy was late presentation to the hospital (> 12 hours from the beginning of symptoms). Only 11 high-risk patients in NSTEMI group underwent primary PCI and 99 NSTEMI patients received conservative therapy (in-hospital mortality 10.1%). We performed totally 218 urgent PCI interventions in both groups with low in-hospital mortality of 6.1% in comparison with high mortality in conservatively treated groups of patients. The mortality in PCI group was strongly connected with unsuccessful intervention and late reperfusion. Total ischemic time (6 hours and 5 minutes), and time from hospital presentation to reperfusion -"door to balloon time" (1 hour and 25 minutes) are longer that in similar patients series, and need to be improved. Transportation time (1 hour and 40 minutes) is acceptable. In conclusion, high percentage (70.1%) of STEMI and NSTEMI patients underwent primary PCI in our institution with low perioperative mortality. This group of patients had superior in-hospital mortality when compared with conservatively treated group of patients. There is still unacceptably high percentage of patients with AMI, who came into the hospital too late for any reperfusion therapy.