One hundred and forty-two consecutive patients with unexplained chest pain and normal coronary arteries were followed up for a mean period of 49.3 +/- 13.1 months. No cardiac deaths and one myocardial infarction occurred. Half of the patients were pain-free at follow-up. A definite relationship between persistence of pain and duration of pain history and a positive response to nitroglycerin before coronary arteriography were found. Patients with persistent pain were more frequently hospitalized for noncardiac diseases, underwent more surgical interventions and took more often noncardiac medication. Rehospitalizations for acute chest pain were infrequent. Two thirds of the patients resumed their normal activities. Younger age, disappearance of pain, type of occupation, and a shorter duration of the pain history favored return to work. Nonactive patients presented more intercurrent noncardiac, medical and surgical pathology. The findings in patients with a previous myocardial infarction were similar to those of the group with only chest pain.