Natural history of Wolff-Parkinson-White syndrome discovered in infancy

Abstract

The prognosis of 20 infants with a diagnosis of Wolff-Parkinson-White syndrome under 1 year of age is presented. Children were followed up from 1 to 19 years (mean 9 years). Seven patients had associated congenital heart disease. Analysis of the associated arrhythmias revealed episodes of supraventricular tachycardia in 18 (90 percent). During paroxysmal supraventricular tachycardia the QRS complex was normal in seven and wide in nine children. Categorizing patients into groups according to the width of the QRS complex and the presence or absence of a delta wave during tachycardia helps in understanding and planning therapy. Eighteen patients had a stable or improved course with growth but two patients with tetralogy of Fallot died postoperatively with resistant supraventricular tachycardia. The high prevalence rate of supraventricular tachycardia during infancy which later decreases or disappears could be explained by the different electrophysiologic responses between normal and accessory pathways during the fast heart rate characteristic of this young age. Invasive electrophysiologic studies are indicated in children older than 1 year of age who remain symptomatic and in all children being conconsidered for cardiac surgery regardless of the effectiveness of the preoperatlve therapy.