[Epicardial VT ablation : In whom, when, how and why?]

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Imaging

Background:

• Ventricular tachycardia (VT) is a major cause of sudden cardiac death.
• Implanted cardiac defibrillators (ICDs) reduce mortality but recurrent therapies, like shocks, increase mortality and cause psychological distress.
• European guidelines recommend early catheter ablation for recurrent VT.

Purpose of the Study:

• To review the role of catheter ablation strategies for ventricular tachycardia.
• To highlight the importance of identifying epicardial scar substrates for VT.
• To emphasize the benefits of combined epicardial and endocardial ablation approaches.

Main Methods:

• Review of multicenter studies and current European guidelines.
• Analysis of ablation strategies based on underlying myocardial disease and scar location.
• Utilizing cardiac imaging (cardio-CT/MRI with late enhancement) for scar characterization and ablation planning.

Main Results:

• Epicardial scars are common substrates for VT in conditions like right ventricular dysplasia, Chagas disease, and certain cardiomyopathies.
• Isolated endocardial ablation may lead to higher VT recurrence if epicardial scar is present.
• Epicardial catheter ablation, when performed in specialized centers, significantly reduces VT recurrence compared to endocardial ablation alone, with lower complication rates.

Conclusions:

• Catheter ablation is a key therapy for managing recurrent ventricular tachycardia.
• Identifying epicardial substrates through cardiac imaging is vital for selecting the optimal ablation strategy.
• Combined epicardial and endocardial approaches, particularly for scar-related VT, improve patient outcomes and reduce recurrence.