sentence: The majority of the patients ( 627/730 , 85.9 % ) underwent implantable cardioverter defibrillator ( ICD ) implantation , and thus this patient population represented a high risk SADS or SCD population.The diagnoses of BrS , LQTS , SQTS and CPVT were according to the continuously updated guidelines from American Heart Association / American College of Cardiology ( AHA / ACC ) and European Society of Cardiology ( ESC ) .