Electrical storm: A clinical and electrophysiological overview

Figure 1 Kaplan-Meier survival analysis after catheter ablation of electrical storm. Class A indicates catheter ablation success, defined as suppression of each ventricular tachycardia (VT) morphology; Class B indicates partial success, defined as suppression of each clinical VT; Class C indicates failure, defined as persistence of one or more clinical VT (reprinted from Carbucicchio et al[20]).

Figure 2 Modern approach of mapping and ablation for the treatment of electrical storm: High-density electroanatomical mapping of the left ventricle using CARTOSOUND contact-force technology (Biosense Webster, Diamond Bar, CA, United States). A: Two distinct peri-valvular scars, in the mitro-aortic continuity and below the mitral annulus, in the setting of idiopathic cardiomyopathy are visualized. Scars are characterized by dense scar (abnormal bipolar electrograms < 0.20 mV), surrounded by a border zone (0.20-1.20 mV) in which late potentials, are tagged (dark and light blue dots); B: Radiofrequency ablation lines are dragged for dechanneling and isolation of all proarhythmic sites; C: Intracardiac echocardiography imaging is aiming at substrate characterization and correct positioning of the catheter during mapping and ablation.