Radiofrequency catheter ablation in children and adolescents with preexcitation syndrome.

BACKGROUND: Atrioventricular reentrant tachycardia (AVRT) is the most common tachycardia, accounting for 70% of regular narrow-QRS arrhythmias in children. Because of the potential disadvantages of a life-long drug therapy and relatively favourable results from radiofrequency catheter ablation (RFCA) therapy in adults, the indications for ablation therapy in children with preexcitation syndrome (PS) need to be considered. AIM: To assess efficacy and safety of RFCA in children and adolescents with PS. METHODS: The study population consisted of 302 consecutive, symptomatic, drug-refractory patients with PS undergoing RFCA. Two age groups were selected: 52 patients younger than 19 years (24 females, age 15.38+/-2.53 years); and 250 adults (115 females, age 38.67+/-13.1 years). In all study patients electrophysiological study and radiofrequency catheter ablation were performed. Comparative analysis between groups was performed with respect to procedure duration, fluoroscopy exposure time, location of accessory pathways (AP), success rate, recurrences and complications. RESULTS: No significant differences between the groups were noted with respect to procedure duration and exposure time. Success and recurrence rates did not differ between the two-age groups. The mean procedure time for children was 124.12+/-43.48 min (range 45-285) and for adults - 126.3+/-61.49 min (range 25-330) (NS). The mean fluoroscopy time for children was 27.95+/-16.86 min (range 4-75) and for adults - 31.27+/-25.51 min (range 1-131) (NS). The initial RF ablation procedure was successful in 48 (92.31%) children and in 233 (93.2%) adults (NS). Recurrence rate was 12.5% (6 patients) in children vs. 8.58% (20 patients) in adults (NS). In one child (1.92%) and in two adult patients (0.8%) serious complication occurred (NS). Electrophysiological study revealed significantly more frequent presence of the right free wall and right antero-septal AP in children than in adults (21.15 vs. 7.6%, and 17.31 vs. 5.2%, respectively, p <0.01). In adults more frequent left antero-lateral AP was detected: 32.4 vs. 7.69%, p <0.01. CONCLUSIONS: Radiofrequency catheter ablation is a safe and efficient procedure in paediatric patients with preexcitation syndrome. Effectiveness, safety, recurrence rate and RFCA procedural aspects, including total procedure time and fluoroscopy time, are comparable in paediatric patients with PS and in adults.

A comparison of the clinical course of preexcitation syndrome in children and adolescents and in adults.

BACKGROUND: Atrioventricular reentrant tachycardia (AVRT) in patients with preexcitation syndrome (PS) is the main cause of paroxysmal regular arrhythmias in children and adolescents. While the previously published data most commonly concern clinical consequences of PS in adults, few researchers have evaluated the problem in children and adolescents. The aim of the study was to compare the clinical course of PS between the population of children and adolescents below 19 years of age and the population of adult patients. METHOD: The study population consisted of 302 consecutive PS patients managed between January 2001 and June 2005 with radiofrequency catheter ablation (RFCA). The study population was divided into two groups: Group 1 consisting of 52 patients aged 15.38 years on average (7-18 +/- +/- 2.53) and Group 2 consisting of 250 adult patients aged 38.67 years on average (19-72 +/- 13.1). RESULTS: Patients from Groups 1 and 2 experienced their first episode of AVRT at the mean age of 13.3 years and 29.1 years, respectively (p < 0.05). The mean annual numbers of AVRT episodes in Groups 1 and 2 were 12.97 (range, 2-96; median, 8) and 8.86 (range, 2-25; median, 6), respectively (p = non-significant). Two patients from Group 1 (3.85%) and 42 patients from Group 2 (16.8%) experienced episodes of atrial fibrillation (AF) (p < 0.05). Location of the accessory pathways (AP): In Group 1, the right free wall and anteroseptal AP locations were significantly more common [11 (21.15%) and 9 (17.31%) patients, respectively, vs.q 19 (7.6%) and 13 (5.2%) patients in Group 2; p < 0.01]. In Group 2, the left anterolateral AP location was more common [81 (32.4%) vs. 4 (7.69%) in Group 1; p < 0.01]. CONCLUSIONS: In children and adolescents with PS, a significantly lower incidence of AF was found. In Group 1, RFCA was performed significantly more frequently due to the development of AVRT caused by right free wall and right anteroseptal AP, while in the group of adults, the left anterolateral AP location was found more commonly. (Cardiol J 2007; 14: 384-390).