Abstract 11418: Ablation of Ventricular Tachycardias in Adults with Congenital Heart Disease: Acute and Long Term Results
INTRODUCTION Ventricular tachycardia (VT) is an important cause of late morbidity and mortality in the increasing population with surgically corrected congenital heart disease (CHD). Radiofrequency catheter ablation (RFCA) of VT may prevent VT recurrence. METHODS Thirty-one patients (49±13 years, 71% male) referred for RFCA of VT after repair of CHD (25 Tetralogy of Fallot (TOF), 2 Ventricular Septal Defect (VSD), 2 D-Transposition of the Great Arteries (D-TGA), 1 Atrioventricular Septal Defect (AVSD), 1 Congenital Pulmonary Stenosis (cPS); age of repair 13±10 years) in two centres were included. Ventricular function was evaluated by echocardiography and/or magnetic resonance imaging. Ablation targeted anatomical isthmuses for VT re-entry circuits identified by 3D substrate, pace- and/or entrainment mapping. Acute success was defined as non-inducibility of any VT, partial success as elimination of clinical VT, failure as inducibility of clinical VT. Patients (pts) were followed for 43±28 months. RESULTS Before RFCA, 7 (23%) pts had ≥moderate impairment of RV and/or LV function. Pts were inducible for 2.0±1.4 VTs, cycle length 297±74ms. Complete procedural success was achieved in 22 (71%) pts (18 TOF, 2 D-TGA, 1 VSD and 1 AVSD), partial success in 3 pts (2 TOF and 1 VSD) and in 2 pts (1 TOF and 1 cPS) VT induction was not repeated after RFCA (undetermined outcome). Ablation failed in 4 TOF pts (13%) because the targeted anatomical isthmus could not be transected (hypertrophic myocardium in 2, interposed pulmonary homograft in 2). Twenty-four pts (77%) were discharged with an ICD. During follow-up VT recurred in 4 pts (13%); partial success 1 (VSD), failure 1 (TOF), undetermined 2 pts. One pt (complete success, TOF) with progressive heart failure received one ICD shock for VF. Nineteen pts with complete procedure success and preserved RV and LV function (13/19 with ICDs) had no VT recurrence, however 6/13 ICD pts (46%) received inappropriate therapy. Two pts died during follow-up (heart failure 1, acute leukaemia 1). Conclusion RFCA of VT in adults with CHD is highly effective with a low recurrence rate during long term follow up. In patients with complete procedure success and preserved cardiac function disadvantages of ICD may outweigh benefits.
- © 2012 by American Heart Association, Inc.