TRDN and catecholaminergic polymorphic ventricular tachycardia: Recent studies identified causative mutations in TRDN gene (OMIM #603283), encoding TRIADIN protein, in a small number of pediatric cases with overlapping features of LQTS and CPVT [5,6,7,8,9], a condition termed “Triadin KnockOut Syndrome” (TKOS) [10].