Pharmacological treatment of young children with permanent junctional reciprocating tachycardia.

Our objective was to assess the efficacy of pharmacological treatment in reducing the incidence of permanent junctional reciprocating tachycardia in young children, or to bring the mean heart rate over 24 h to a normal level. We included 21 children with a median age of 0.05 year seen with permanent junctional reciprocating tachycardia over the period 1990 through 2001. Of these children, two had abnormal left ventricular function. Follow-up visits were made at least every 6 months. We registered the presence of the tachycardia over 24 h, the mean heart rate over 24 h, and cardiac function. Treatment was started with propafenone alone, or in combination with digoxin as the first choice. Treatment was effective in 14 cases (67%), with either complete disappearance of the tachycardia after discontinuation of medication, or continuation in sinus rhythm with medication; partially effective in 4 cases (20%) when the mean heart rate over 24 h on the last Holter recording was less than 1 standard deviation above the normal for age; but was not effective in the remaining 3 cases (14%). In 3 patients treated with propafenone, or 13 given propafenone and digoxin, treatment was effective in 12 (75%), partially effective in 2 (13%), and ineffective in the other 2 (13%). All 21 children had a normal left ventricular function at the end of follow-up. The median duration of follow-up was 2.4 years. Permanent junctional reciprocating tachycardia had disappeared spontaneously in one-third of the children, 5 being less than 1 year old. Adverse effects, seen in 5 cases, were mild or asymptomatic. No signs of proarrhythmia were registered. Pharmacological treatment, either with propafenone alone, or in combination with digoxin, is safe and effective in young children with permanent junctional reciprocating tachycardia. The mean heart rate is normalized, and cardiac function is restored and preserved. Radiofrequency ablation may be delayed to a safer age, with the arrhythmia disappearing spontaneously in one-third.