Background: The role of radiofrequency catheter ablation (RFCA) of supraventricular tachycardia (SVT) in infants and toddlers is still unclear.
Methods and results: From 1993 to 2006, 27 (17 males, 10 females) of 210 patients underwent RFCA at an age less than 6 years. Indications included drug-refractory SVT or tachycardia-induced cardiomyopathy. The medical records were reviewed and the patients were interviewed regarding their current status. The 27 patients underwent RFCA at a median age of 4.4 years (8 months to 5.9 years) and a median body weight of 15 kg (6.6-30 kg). The SVT was mainly atrioventricular reentry tachycardia (15/27) and multiple mechanisms in 3. One-third of them had associated congenital heart disease, and 5 underwent RFCA using only 2-3 catheters. Immediate success rate was 92.6%, with low early (3.7%) and late recurrence (7.4%) after 5.4 +/-3.7 years follow-up. Tachycardia-induced cardiomyopathy was noted in 4 and resolved in all after RFCA. Procedure-related complications included complete atrioventricular block in 1 and Bezold-Jarisch reflex in another. No other risk factors for outcomes were noted, even with low body weight.
Conclusions: The outcome of RFCA for medically refractory SVT, even associated with tachycardia-induced cardiomyopathy, in infants and toddlers is favorable.