Clinical Aspects and Ablation of Ventricular Arrhythmias in Tetralogy of Fallot.

Life expectancy of patients with rToF has considerably improved due to refined surgical interventions. Monomorphic fast VTs are frequently encountered in adult patients with rToF. The dominant substrate of VT is anatomical isthmuses bordered by surgical incisions, patch material and valve annuli. Substrate based ablation strategies aim to transect all slow conducting anatomical isthmuses (SCAI) as identified by electroanatomical mapping. Procedural success is defined as non-inducibility of VT and confirmed conduction block over the SCAI resulting in long-term VT free survival in most patients. The identification of SCAIs in rToF may have important implications for risk stratification and preventive treatment.