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Substrate Mapping in Ventricular Arrhythmias.

Roderick Tung¹

¹Department of Medicine, Section of Cardiology, The University of Chicago Medicine, Center for Arrhythmia Care, Pritzker School of Medicine, 5841 South Maryland Avenue, MC 6080, Chicago, IL 60637, USA.

Cardiac Electrophysiology Clinics

|November 11, 2019

Summary

This summary is machine-generated.

Targeting the arrhythmogenic substrate during sinus rhythm is crucial for ventricular tachycardia ablation. Isochronal late activation mapping identifies critical reentry zones within scar tissue, improving ablation specificity.

Keywords:

Bipolar Electroanatomic mapping Electrograms Isochronal Ventricular tachycardia Voltage mapping

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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

Area of Science:

Cardiology
Electrophysiology
Medical Imaging

Background:

Ventricular tachycardia (VT) often presents with hemodynamic instability, necessitating effective ablation strategies.
Current substrate-based ablation relies on electroanatomic mapping, primarily bipolar voltage mapping, to identify scar regions.
Bipolar voltage mapping has limitations in precisely localizing the most arrhythmogenic areas within the scar substrate.

Purpose of the Study:

To explore the utility of specific electrogram characteristics for improving the specificity of VT substrate localization.
To investigate isochronal late activation mapping as a method to identify critical reentry zones during sinus rhythm.

Main Methods:

Utilizing bipolar voltage mapping to delineate scar regions.
Analyzing specific electrogram characteristics within the scar.
Employing isochronal late activation mapping during sinus rhythm to assess substrate propagation.
Annotating local electrogram offset for functional analysis.

Main Results:

Deceleration zones during sinus rhythm are identified as potential arrhythmogenic nidi.
Isochronal late activation mapping provides a functional analysis of substrate propagation.
Local electrogram offset annotation aids in pinpointing critical areas within the substrate.

Conclusions:

Specific electrogram characteristics, particularly deceleration zones identified by isochronal late activation mapping, enhance the specificity of VT substrate localization.
This functional mapping approach during sinus rhythm is essential for guiding precise therapeutic ablation within arrhythmogenic scar regions.