Background: The aim of this study was to assess the prognosis and the clinical course of incessant idiopathic ventricular tachycardia (VT) with left bundle branch morphology, in a group of 14 children consecutively evaluated in our institutions between 1983 and 1994.
Methods: Mean age of these patients was 8 +/- 2 years, and they were followed for 56 +/- 32 months. In all the children, VT was present for more than 80% of the day, in non sustained runs. The mean rate of VT was of 142 +/- 30 beats/min. Four children were symptomatic. The evaluation of these children was obtained by treadmill stress test (12/14), cardiac catheterization (13/14), electrophysiologic study (10/14), nuclear magnetic resonance (7/14), and serial echocardiographic and Holter examinations.
Results: Right ventricular dysplasia was suspected in 2 cases on the basis of nuclear magnetic resonance and angiographic data. In both these cases VT was not suppressed by exercise. Medical treatment was started in 9/14 patients (69%), it was completely effective in 4 (44%) and partially effective in 2 further cases (22%). Thirteen out of fourteen patients had a regular follow-up. No patient died. All patients remained asymptomatic and in 6 (46%) VT disappeared. In 4 of these last 6 patients therapy has been previously effective. Two children, one with right ventricle dysplasia, continue antiarrhythmic treatment.
Conclusions: Incessant VT is well tolerated in pediatric age. The frequency of spontaneous remissions is relatively high (46% of cases). In few patients this arrhythmia is associated with evident cardiac abnormalities. In our opinion, medical treatment is necessary in symptomatic patients and in those with heart abnormalities.