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Related Experiment Video

Updated: Aug 20, 2025

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction

Published on: January 31, 2019

Intracardiac Electrogram Targets for Ventricular Tachycardia Ablation.

Sachin Nayyar¹

¹Townsville University Hospital, James Cook University, Townsville, Queensland, Australia.

Cardiac Electrophysiology Clinics

|November 17, 2022

Summary

This summary is machine-generated.

Identifying ventricular tachycardia (VT) targets in sinus rhythm is crucial for ablation. High-density electrograms and substrate mapping help pinpoint critical areas within myocardial scars.

Keywords:

Ablation Channel Electrogram Fibrosis Late potential Pacing Slow conduction Ventricular tachycardia

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Published on: December 11, 2017

Area of Science:

Cardiology
Electrophysiology
Medical Devices

Background:

Ventricular tachycardia (VT) often stems from reentry mechanisms in scarred myocardial tissue post-infarction.
Identifying VT ablation targets during sinus rhythm presents a significant clinical challenge, especially when VT morphology is unknown.

Purpose of the Study:

To discuss contemporary intracardiac electrogram targets for VT ablation.
To explain the fundamental physiology behind these electrogram targets.

Main Methods:

Utilizing high-density electrogram recordings for substrate evaluation.
Assessing electrogram voltage and activation delay.
Employing substrate perturbation techniques like alternate site pacing and extra-stimulus testing.

Main Results:

High-density mapping provides essential data for identifying ablation targets in sinus rhythm.
Specific electrogram characteristics correlate with arrhythmogenic substrate.
Substrate perturbation aids in uncovering critical areas for ablation.

Conclusions:

Intracardiac electrogram targets are vital for successful VT ablation in patients with myocardial scarring.
Understanding the underlying physiology of these targets optimizes ablation strategies.
Advanced mapping techniques are key to managing complex VT cases.