Ventricular Tachycardia Ablation Guided by Functional Substrate Mapping: Practices and Outcomes.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Catheter ablation is crucial for treating ventricular tachycardia (VT) in structural cardiomyopathy.
• Conventional mapping (activation, entrainment) faces limitations due to non-inducible VT or hemodynamic instability.
• Voltage mapping shows low specificity (30%) for identifying VT isthmuses.

Purpose of the Study:

• To review and summarize functional mapping strategies for identifying ventricular arrhythmic substrate.
• To address limitations of conventional and voltage mapping in structural heart disease patients.

Main Methods:

• Functional mapping analyzes electrogram characteristics, propagation patterns, and responses to pacing.
• Utilizes extra-stimulus testing and alternative pacing wavefronts to define ablation targets.
• Focuses on identifying the critical isthmus for VT ablation.

Main Results:

• Functional mapping offers a more comprehensive approach than conventional methods.
• It aims to improve the specificity and efficacy of catheter ablation for VT.
• This review consolidates various functional mapping techniques for substrate identification.

Conclusions:

• Functional mapping strategies are essential for effective VT ablation in structural heart disease.
• These methods enhance the identification of critical VT substrate, improving treatment outcomes.
• Further research and standardization of functional mapping techniques are warranted.