Out-of-hospital ventricular fibrillation in patients under the age of 40 years and the long-term prognosis.

Among patients with ventricular fibrillation outside hospital seen by our mobile coronary care unit between 1967 and 1988, 28 were aged less than 40 years (range 12-39, mean 28). Coronary artery disease was present in 11 (39 per cent) and was the most common single cause, although none of these patients was aged less than 28 years. Of 15 patients with cardiac disease, only four (27 per cent) had previously sought medical advice. Nineteen patients (68 per cent) collapsed without preceding symptoms. Survival to reach hospital was significantly associated with bystander cardiopulmonary resuscitation and early defibrillation. Eleven patients (39 per cent) survived to hospital discharge, of whom seven remain alive after 2 1/2 to 21 1/2 years, five without symptoms. Thus, as demonstrated for older patients, coronary artery disease is an important cause of sudden death in this age group, and bystander cardiopulmonary resuscitation and early defibrillation are important for survival. Most of these patients collapse without warning and are not already known to have cardiac disease.