Lesion Depth Optimization in High-Power Radiofrequency Ablation: Evaluating Single High-Power and Combined Very...

Area of Science:

• Electrophysiology
• Cardiac Ablation
• Radiofrequency Ablation

Background:

• Very high-power short-duration (vHPSD) radiofrequency (RF) ablation may create insufficient lesion depth in thick myocardial tissue.
• Thicker myocardial regions require strategies to ensure adequate lesion creation for effective ablation.

Purpose of the Study:

• To evaluate effective ablation strategies after initial vHPSD application.
• To determine the optimal approach for achieving sufficient lesion depth in thick myocardial regions using ex vivo and in vivo models.

Main Methods:

• Comparison of lesion metrics under different RF power settings (35W vs. 50W) with consistent ablation index (AI).
• Evaluation of double vHPSD ablations versus sequential vHPSD and AI-guided ablation.
• Assessment of double applications (DA) versus single application (SA) strategies using vHPSD and AI-guided ablation at varying AI targets and power.

Main Results:

• Lesion depth was similar between groups with the same AI but different RF powers.
• vHPSD followed by AI-guided ablation (AI 450) resulted in significantly deeper lesions compared to double vHPSD (4.4-4.5 mm vs. 3.4 mm).
• Single high-power application (SA) with AI 550 yielded deeper lesions than vHPSD + AI 450 (5.0 mm vs. 4.5 mm).

Conclusions:

• AI-guided RF applications post-vHPSD enhance lesion depth more effectively than repeated vHPSD applications.
• A single high-power application targeting a higher AI achieves the greatest lesion depth.
• This strategy is potentially beneficial for thick atrial myocardial regions, improving lesion durability and procedural success.