The aim of the study is to compare the efficacy and safety of treating recurrent sustained Ventricular Tachycardia (sVT) after prior Catheter Ablation (CA) in patients with Implanted Cardioverter-Defibrillator (ICD) between re-do of conventional endocardial CA and Stereotactic Arrhythmia Radioablation (STAR).
Age ≥ 18 years at the time of enrollment.
Presence of structural heart disease (SHD) of either ischemic or non-ischemic etiology.
Implanted ICD or CRT-D device for primary or secondary prevention of sudden cardiac death (SCD).
History of at least one endocardial CA procedure targeting a substrate of monomorphic sVT.
Reversible cause of sVT recurrence, particularly acute coronary syndrome (ACS), acute myocarditis, or lead-related infective endocarditis (LDIE).
Myocardial infarction (MI) or cardiac surgery within the last 40 days.
Idiopathic sVT unrelated to SHD or sVT associated with genetically determined channelopathies.
Ongoing or persistently recurrent hemodynamically unstable sVT until clinical stabilization is achieved.