Ventricular tachycardia is clinically presented by ECHO, CAD, ARVC, ARVD, PMVT and VF. Non life threatening ventricular arrhythmias for monomorphic includes general considerations, outflow tract ventricular arrhythmia, electrophysiologic mechanism and their clinical features, idiopathic left ventricular tachycardia and mitral annulus, tricuspid annulus, papillary muscle, perivascular epicardial ectopy. Life threatening ventricular arrhythmias for polymorphic general considerations, long QT syndrome, Brugada syndrome, catecholaminergic PMVT, short QT Syndrome and idiopathic ventricular fibrillation. Patients require ICD therapy for secondary or primary prevention of SCD.