Hosts Mitsuaki Sawano, MD, and Nobuhiro Ikemura, MD, welcome Yoshitaka Kimura, MD, PhD, of Leiden University Medical Center, to discuss proactive ablation strategies in patients with repaired Tetralogy of Fallot (rTOF). Dr. Kimura presents data from a long-term, single-center study evaluating electroanatomical mapping and preventive ablation of slow-conducting anatomical isthmuses (SCAI) in rTOF patients without prior ventricular tachycardia (VT). The findings show that identifying and successfully ablating SCAI significantly reduced VT incidence, with all VT events occurring in patients where ablation failed. Moreover, this approach reduced the proportion of patients qualifying for ICD implantation from 25–51% under current guidelines to just 11%. Dr. Kimura underscores a paradigm shift in congenital heart disease management—from treating VT reactively to preventing it proactively—highlighting the value of data-driven, tailored care strategies that avoid unnecessary device implantation and better target high-risk individuals.