Ventricular Tachycardia


Ventricular tachycardia (VT) is an arrhythmia caused by abnormal electrical signals in the lower chambers of the heart, resulting in a rapid heartbeat. The arrhythmia, which does not always have symptoms, may last for seconds or much longer. The condition most commonly affects people who have heart disorders, such as coronary artery disease and cardiomyopathy.


While automatic implantable defibrillators are effectively used to treat this arrhythmia, they do not prevent implantable cardioverter defibrillator (ICD) shocks. Catheter ablation has emerged as the only therapeutic strategy to treat ventricular tachycardia and ventricular fibrillation. We perform endocardial and epicardial radiofrequency ablation for ventricular arrhythmias using several different techniques and approaches, which include:



Areas between channels often have electrical activity that give rise to VT substrates (thunderbolts). Elimination of scar-related potentials is a relevant ablation goal and is the basis of different substrate-based ablation strategies.

Scar Dechanneling
Identification of a corridor of consecutive electromyograms (EGM) with delayed components (conducting channels) and subsequent ablation of the entrance regions.
(See above: A)

Late Potentials and Local Abnormal Ventricular Activities (LAVA)
Late Potentials (LPs): Ablation of any low voltage EGM (<1.5 mV) with a single component or multiple continuous delayed components recorded after the surface QRS.

Late Potentials and Local Abnormal Ventricular Activities (LAVA): Ablation of sharp high-frequency ventricular potentials occurring anytime from the ventricular EGM (before-VT; during/after normal sinus rhythm (NSR).
​​​​​​​(See above: B)

Learn More

Core Isolation 
Isolation of the area that incorporates VT circuit elements.
​​​​​​​(See above: C)

Ablation lesions aimed to cover the entire scar (homogenization of the scar), thereby targeting all abnormal electrograms.
​​​​​​​(See above: D)

Electroanatomic voltage map of the left ventricle


Top left, bottom left and right illustrate the bipolar map in septal anterior and inferior views of the scar in the left ventricle. Top right depicts the unipolar voltage map of the left ventricle suggesting large transmural component of the scar. Septal and anterior views of the left ventricle showing radiofrequency ablation (RFA) lesions to perform substrate modification of the left ventricle (LV) septal scar. Red dots: RF lesions, gray tags denote areas or unexcitable scar.