Brugada-Like Syndrome in Infancy Presenting with Rapid Ventricular Tachycardia and Intraventricular Conduction Delay
Background—Brugada syndrome (BrS) is a potentially serious channelopathy, which usually presents in adulthood and has only rarely been described in infancy. In the absence of metabolic or structural cardiac disease, rapid ventricular tachycardia (>200 bpm) (VT) and primary cardiac conduction disease are uncommon in infancy. We hypothesized that infants having rapid ventricular tachycardia and conduction abnormalities and not having structural or metabolic etiologieswere likely to have mutations in depolarizing current channels.
Methods and Results—A retrospective review of all clinical materials from a single institution over a nine year period from all infants less than two years old and having a discharge diagnosis of “ventricular tachycardia” or “ventricular fibrillation” was performed. Amongst 32 infants fulfilling inclusion criteria, 12 had a structurally normal heart, and nine of them had either prolonged QRS duration or Brugada pattern while in sinus rhythm. Of those five infants not having a definitive etiology, electrophysiological testing (EP) had been performed in four and genetic testing had been performed in all five of those infants. During EP, a prolonged HV interval was present in 2/4, inducible VT in 1/4, and a type 1 Brugada pattern was induced by intravenous procainamide in 3/4. Genetic testing revealed disease-causing mutations in depolarizing sodium (SCN5A) and/or calcium (CaCNB2b) channels in all five infants.
Conclusions—Infants having rapid ventricular tachycardia and conduction abnormalities in the absence of structural or metabolic abnormalities are likely to have disease-causing mutations in cardiac depolarizing channels.
- Received July 6, 2011.
- Accepted October 3, 2011.
- Copyright © 2011, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited