Abbreviated combined anatomical/electrophysiological approach for catheterablation of atrioventricular nodal reentrant tachycardia in children

Atrioventricular nodal reentrant tachycardia was proven during electrophysi ologic study in 41 children, aged from 3.7 to 16 years, who were referred f or catheter ablation of symptomatic supraventricular tachycardia. Using an abbreviated combined anatomical and electrogram-guided approach for selecti ve ablation of the slow pathway, a steerable ablation catheter was placed a t the inferior region of the vestibule of the tricuspid valve close to the orifice of the coronary sinus, with the intention of recording a multicompo nent local atrial electrogramm during sinus rhythm. If application of radio frequency current of 500 kHz at 70 degreesC at this site did not result in a slowly accelerated junctional rhythm, at a rate of less than 120 beats pe r minute, the catheter was stepwise advanced up to a position midway toward s the apex of the triangle of Koch for additional applications of energy. A blation was achieved in 35 of the patients. In 6 patients, the slow pathway was modulated such that the tachycardia could no longer be induced. The nu mber of applications of energy ranged from 1 to 19, with a median of 6 appl ications. The mean period of fluoroscopy was reduced to 15.6 (4.3 to 39.8) minutes, while the overall duration of the catheterization procedures range d from 88 to 280 (mean 173.2) minutes. In none of the patients did we obser ve permanent high grade atrioventricular block. During follow-up over a mea n of 4.1 years, two patients had recurrence of tachycardia, corresponding t o a 95% rate of success in the midterm. We conclude that selective radiofre quency ablation of the slow pathway using the abbreviated anatomical and el ectrophysiological approach is a safe and curative therapeutic approach in children with atrioventricular nodal reentrant tachycardia. Periods require d for fluoroscopy can be significantly reduced, and mid-term results are ex cellent.