Sudden unexpected death from cardiovascular disease in children. A cooperative international study

The results of an international cooperative study of sudden unexpected death from cardiovascular disease in children are reported. Sudden natural death was defined as death occurring instantaneously or within 24 hours of the onset of acute symptoms or signs in ambulatory, nonhospitalized children aged 1 to 21 years. Twenty institutions representing 10 countries contributed a total of 254 acceptable case reports. In 186 cases the child had had no cardiac surgery. Four heart conditions accounted for 53 percent of these “medical” deaths: congenital aortic stenosis (18 percent), Eisenmenger's syndrome (15 percent), cyanotic congenital heart disease with pulmonary stenosis or atresia (10 percent) and hypertrophic obstructive cardiomyopathy (9 percent). A total of 33 types of cardiovascular disease were reported. Sixty-eight chlldren died months or years after cardiac surgery. In 28 of these 68 patients death appeared to be causally related to the preceding surgery rather than to the underlying cardiovascular disease. All but 2 of the 28 probably died of an arrhythmia, usually without warning.The period between the onset of acute signs and symptoms (terminal episode) was less than an hour (usually instantaneous) in 73 percent of all 254 patients. In 95 percent of patients in the “medical” group heart disease was known or suspected, but a majority of these patients were asymptomatic. Warning syncope occurred in only 16 percent. A majority of the patients (58 percent) were inactive at the time of the terminal episode (Standing, sitting, lying or sleeping). Only 10 percent were engaged in active sports.This large study appears to establish better than previous data the relative frequency of sudden unexpected death among children with heart disease in Western Europe and Central and North America. Surgical and medical preventive measures, and the indications for engaging in sports, are discussed.