[Transcatheter radiofrequency ablation in supraventricular tachycardia in children: immediate results and mid-term follow-up].
OBJECTIVE
The purpose of this study was to evaluate the efficacy and safety of radiofrequency ablation of supraventricular tachycardias due to a reentry circuit in a group of closely followed-up pediatric patients.


METHODS
Forty-six pediatric patients (mean age 12.6 years, range 3-18) underwent a total of 48 radiofrequency ablation procedures for reciprocating supraventricular tachycardia. Thirty-nine had an orthodromic reentry tachycardia, 6 an atrioventricular node reentry tachycardia and 1 a permanent junctional reciprocating tachycardia.


METHODS
To ablate the overt accessory pathways, the Kent potential (K) was identified and then the shortest A-K, and delta wave-K intervals were measured. The shortest V-A interval was identified for those concealed. For the left-sided accessory pathways, we used the retrograde transaortic approach in 10 procedures and the transseptal approach in 18. Atrioventricular node reentry tachycardia was ablated at the site where the slow-pathway electrogram was recorded. Follow-up clinical data, electrocardiogram, 24-hours Holter monitoring and transesophageal atrial stimulation were obtained and evaluated.


RESULTS
Early: We performed a total of 48 procedures. Among 41 procedures performed in the 39 patients with accessory pathway, 38 were successful (92,6%). Mean fluoroscopy time was 31 +/- 18 min. For left sided accessory pathways, mean fluoroscopy time of procedures with retrograde approach was 45 +/- 10 min and with transseptal 23 +/- 12 min (p < 0.01). Ablation of slow-pathway in patients with intranodal reentry tachycardia was successful in 3/6 cases (50%). The patient with permanent junctional reciprocating tachycardia was successfully ablated. Late: All patients are alive and none was lost during the follow-up after a mean time of 12.9 months (range 5-33). Success at last follow-up was 100% in patients with an accessory pathway and 33% in patients with atrioventricular node reentry. In patient with permanent junctional reciprocating tachycardia, the arrhythmia appeared again one month after the procedure, thus a second successful attempt was performed.


RESULTS
Major complications (6,5%) including a right femoral vein thrombosis (one patient), an hematoma without pulse loss (one patient) and a non-sustained monomorphic ventricular tachycardia (one patient).


CONCLUSIONS
Our data show high efficacy of radiofrequency ablation in pediatric patients with accessory pathways. The risks are low at follow-up evaluation, but might be helpful a longer-term follow-up in order to evaluate the risk of a long fluoroscopy time and the arrhythmogenic effect of the scar.
Montenero
A S
AS
Istituto di Cardiologia, Università Cattolica del Sacro Cuore, Roma.
Drago
F
F
Crea
F
F
Varano
C
C
Guarneri
S
S
Cipriani
A
A
Pelargonio
G
G
Agostino
D A
DA
Bellocci
F
F
Ragonese
P
P
Zecchi
P
P
D000293:Adolescent; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D002648:Child; D002675:Child, Preschool; D003627:Data Interpretation, Statistical; D004562:Electrocardiography; D004594:Electrophysiology; D005069:Evaluation Studies as Topic; D005500:Follow-Up Studies; D006801:Humans; D012008:Recurrence; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D013613:Tachycardia, Ectopic Junctional / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D013617:Tachycardia, Supraventricular / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors
Ablazione transcatetere con radiofrequenza delle tachicardie sopraventricolari in età pediatrica: risultati immediati e di un follow-up a medio termine.