OBJECTIVE: To increase our understanding of patients' reactions and behavior at onset of symptoms of myocardial infarction. PROCEDURE: During a 5-month period a questionnaire focusing on symptoms, thoughts, and environmental factors at onset of symptoms was administered to all patients admitted to the coronary care unit at Sahlgrenska Hospital in Göteborg, Sweden, because of suspected acute myocardial infarction. RESULTS: A myocardial infarction developed in 48% of the 226 patients answering the questionnaire. In 81% of the patients, chest pain was the main symptom bringing them to the hospital. Forty-three percent characterized their symptoms as an oppression or uncomfortable feeling. Eighty-five percent suspected that the pain emanated from the heart, and yet 51% hesitated to go to the hospital, mainly because they expected the pain to disappear. Efforts to relieve pain were made by 63%, (mostly with nitroglycerin), which was taken more often by patients who did not subsequently develop a myocardial infarction than by those who did. Only 50% of the patients used an ambulance for transportation to hospital. There was a significant relation between subjective assessment of severity of symptoms and 1-year mortality (p < 0.05) and rehospitalization rate (p < 0.01), respectively. CONCLUSION: The majority of patients seem to interpret the symptoms of a myocardial infarction correctly and also have a correct perception of the severity of symptoms. For only a few is the natural next step to immediately call for an ambulance to get to the hospital.