NATURAL-HISTORY OF HYPERTROPHIC OBSTRUCTI VE CARDIOMYOPATHY IN CHILDHOOD - RESULTS OF A SERIES OF 40 CASES

This retrospective study analysed the outcome of children with hypertr ophic obstructive cardiomyopathy. Between 1969 and 1992, 40 patients a ll under 20 years of age (mean = 10.9 +/- 6.2 years) were followed up for this condition. There was a positive family history of hypertrophi c cardiomyopathy and/or sudden death in 21 cases (53 %); 21 (53 %) wer e symptomatic: > NYHA Stage II dyspnoea (n = 13); chest pain (n = 8); syncope (n = 7) or palpitations (n = 4). Thirty-two patients were trea ted by betablockers, 1 by verapamil, 2 by amiodarone (associated with propranolol in 1 case); 7 patients underwent surgery and 6 others, asy mptomatic, had no specific treatment. The mean follow-up period was 10 .2 +/- 6.2 years with no drop-out: 13 patients died (1 non-cardiac dea th, 2 of unknown causes and 10 of cardiac causes, including 8 sudden d eaths) giving an annual global mortality of 3.2 %; the actuarial 5 and 10 year survival rates were 90 and 85% respectively. The 27 survivors were compared with the 13 patients who died: of the 11 clinical and p araclinical criteria examined, only a previous history of syncope corr elated with global mortality (p = 0.004) and sudden death (p = 0.0008) .