Right ventricular outflow tract tachycardia in children

Objective

To assess the clinical spectrum of right ventricular outflow tract tachycardia and its management in children.

Study design

Five centers identified patients for retrospective review. Patients (age <18 years) demonstrating ventricular tachycardia with an inferior axis and left bundle branch block were included. Patients with structural heart disease, myocarditis, cardiomyopathy, or long QT syndrome were excluded. Demographics, clinical presentation, investigations, and treatment were analyzed. Holter data were used to quantify ectopy.

Results

Patients (n = 48) were referred for evaluation of incidental findings (39/48), near syncope or syncope (7/48), or other (2/48). Investigations included magnetic resonance imaging (51%), endomyocardial biopsy (25%), and angiography (23%). Medical treatment was initiated in 26 of the 48 patients. The most common indications for treatment were frequent ectopy and symptoms. Medical treatment (P <.007) and observation alone (P <.02) were both associated with a reduction in ectopy. Symptoms persisted in 3 of 13 patients who were treated medically and in all untreated patients. At follow-up, there were no deaths and no difference in ectopy (P <.46) between patients who were treated medically and patients who were observed. Ablation was attempted in 6 of the 48 patients (successful in 4/6).

Conclusion

The clinical spectrum and management of right ventricular outflow tract tachycardia in children are diverse. Both medical therapy and observation alone were associated with a reduction in ectopy.

Abbreviations: ARVC, Arrhythmogenic right ventricular cardiomyopathy, CPEWG, Canadian Pediatric Electrophysiology Working Group, ECG, Electrocardiogram, EP, Electrophysiology, MRI, Magnetic resonance imaging, RV, Right ventricular, RVOT, Right ventricular outflow tract, RVOT VT, Right ventricular outflow tract tachycardia, VT, Ventricular tachycardia