Abstract 12887: Radiofrequency Catheter Ablation to Ventricular Tachycardia with Tetoralogy of Fallot [[Unable to Display Character: ―]]Usefulness of Ablation to Narrow Channel of Macroreentrant Circuit Around Ventricular Septal Patch[[Unable to Display Character: ―]]
[Background] Cather ablation (CA) of ventricular tachycardia (VT) after repair of tetralogy of Fallot (TOF) can be difficult because of complex anatomy and/or hypertrophied myocardium. In such patietns, to identify critical reentry critical reentry circuit isthmuses is very important for efficacy of CA.
[Methods] Thirteen consecutive TOF patients (5 females, 8 males) with stable monomorphic sustained VT were investigated. The mean age was 25 ± 7 years. The mapping procedure to determine the adequate site for ablation included pace mapping during sinus rhythm, endocardial activation mapping and entrainment mapping during VT. The isthmus of the reentrant circuit was verified by rapid pacing at the site where the tachycardia could be entrained without alteration of the QRS configuration.
[Results] Twenty sustained monomorphic VTs were induced in all patients using programmed stimulation. The mean cycle length of tachycardia was 346±77 msec. The isthmuses were located as follows: between the RV scar and the pulmonary valve (PV) (type 1) in 5 patients, between the RV scar and tricuspid valve (TV) in 2 patients (type 2), between the PV and septal patch in 3 patients (type 3), and between septal patch and the TV in 3 patients (type 4). In patients with type 1 and 2, who had transannular patch in all patients, linear ablation, especially long lesion in type 2, was required. On the other hand, in patients with type 3 and 4, CA in small area between septal patch and PV or TV was enough to suppress the VT. Although 71% in patients with type 1 and 2 had recurrence of VT and/or required anti-arrhythmic drugs, only 33% in patients with type 3 and 4 required anti-arrhythmic drugs.
[Conclusion] The isthmus associated with septal patch might not be uncommon in TOF according to our results, and there might be higher efficacy of CA and good outcome in these isthmuses compared with other ones.
- © 2012 by American Heart Association, Inc.