We have carried out a prospective study to evaluate the time from the onset of symptoms until the admission to coronary care unit in 180 patients with acute myocardial infarction. We have evaluated the causes resulting in a delay and their consequences on the prognosis. The data were obtained with a clinical questionnaire from the patients and/or his family and from a review of the clinical records. The mean time since the onset of symptoms until the admission to the coronary care unit was 5.4 hours, being significantly shorter in the patients who did not call for prehospital attention. The major delay was attributable to the patient (delay in asking for medical attention); therefore, it is mandatory to implement measures of health education. Prehospital attention did not provide any diagnostic or therapeutic improvement in 30% of patients. Thus, we suggest that community care education on coronary artery disease should be improved.