Idiopathic recurrent parasystolic ventricular tachycardia in a child

An asymptomatic 3 1/2-year-old boy demonstrated parasystolic ventricular tachycardia with AV dissociation, early sinus capture beats, marked variability in coupling intervals between conducted and ectopic beats, fusion beats, and interectopic intervals which were multiples of the ectopic cycle length. The arrhythmia initially responded to quinidine, reappeared over an 11-month observation period, and finally was suppressed at a high quinidine dose. An invasive and noninvasive work-up failed to demonstrate organic heart disease.