Epicardial infrared ablation to create a linear conduction block on a beating right atrium

Area of Science:

• Cardiovascular Ablation Technologies
• Cardiac Electrophysiology
• Minimally Invasive Cardiac Surgery

Background:

• Creating a secure linear conduction block on a beating heart from the epicardial side remains challenging.
• A novel infrared coagulator with a cuboid light-guiding quartz rod was developed to address this limitation.

Purpose of the Study:

• To electrophysiologically confirm the efficacy of a new infrared ablation probe in a clinical setting.
• To evaluate the ability of the probe to create a linear conduction block on a beating heart.

Main Methods:

• Infrared light was focused into a cuboid quartz rod with a rectangular exit-plane for linear photocoagulation (30 mm × 10 mm).
• Two pairs of electrodes were placed on the right atrium of a patient undergoing surgery, 10 mm from the ablation line.
• Conduction time between electrode pairs was measured during ablation to assess the delay ratio.

Main Results:

• The actual conduction time post-ablation was 1.38–1.43 times longer than the pre-ablation conduction time.
• The achieved conduction delay ratio closely matched the predicted ratio of 1.54.

Conclusions:

• Infrared ablation utilizing the new cuboid probe successfully created a linear conduction block on the beating right atrial free wall.
• This technology offers a promising solution for epicardial ablation in clinical practice.