Probability of supraventricular tachycardia recurrence in pediatric patients.

Supraventricular tachycardia (SVT) in pediatric patients is usually associated with a better prognosis than that in adults. However, late recurrence of SVT has been recently described. A total of 90 patients who had their initial SVT episode before 15 years of age were retrospectively studied (2-228 follow-up months; median, 215 months). Concomitantly congestive heart failure was present in 14 (16%) patients, and a cerebrovascular accident occurred in 1 patient. Intravenous verapamil was most frequently used to convert the initial SVT episodes without adverse effects, even in those younger than 1 year of age (9 patients). Older children could also be converted spontaneously or by vagal maneuvers. Patients with SVT recurrence were associated with an older age at initial SVT episodes (p < 0.001). By Kaplan-Meier actuarial analysis, the chance of remaining SVT-free during the follow-up was much lower in patients with initial SVT after 5 years of age than in patients with initial attacks before the age of 1 and between the age of 1 and 5 (p = 0.02 and 0.04, respectively). Even though, about 40% of the patients whose initial attacks occurred during infancy had recurrences 5 years later. Only those who had the initial attacks during the prenatal period remained free from SVT recurrences. Patients with initial SVT episodes during infancy have a longer period without SVT attacks and a lower chance of recurrences; nonetheless, a substantial number of them had recurrence at later childhood except those with initial SVT attacks during the prenatal period.(ABSTRACT TRUNCATED AT 250 WORDS)