Mini-electrodes help identifying hidden slow conduction during ventricular tachycardia substrate ablation.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Dilated non-ischemic cardiomyopathy can lead to sustained monomorphic ventricular tachycardia (SMVT).
• VT substrate ablation is challenging when the earliest activation site is near the conduction system.
• Previous ablation attempts may fail due to limitations in identifying critical slow conduction areas.

Observation:

• A 69-year-old male with a history of SMVT underwent an initial unsuccessful VT ablation.
• A second ablation attempt utilized a novel catheter with mini-electrodes (ME) and extrastimuli.
• This approach aimed to uncover hidden slow conduction (HSC) sites crucial for VT substrate.

Findings:

• ME-obtained electrograms accurately localized HSC sites within the VT substrate.
• The successful identification of HSC sites enabled precise ablation during sinus rhythm.
• Post-ablation, no further episodes of SMVT were induced, indicating a successful outcome.

Implications:

• Mini-electrode technology offers a promising method for precise VT substrate mapping.
• This technique facilitates safe and effective ablation of VT in complex cases.
• Improved identification of slow conduction can enhance outcomes for patients with cardiomyopathy and VT.