Thermal side effects during pulsed field ablation: an analysis using computer modelling

Area of Science:

• Cardiology
• Oncology
• Biomedical Engineering

Background:

• Pulsed field ablation (PFA) is considered non-thermal, but thermal effects have been observed in clinical applications.
• The specific parameters influencing thermal energy generation during PFA remain incompletely understood.

Purpose of the Study:

• To numerically assess the thermal effects of PFA on myocardial and esophageal tissues.
• To investigate the influence of varying peak voltage conditions on thermal energy development during PFA.

Main Methods:

• A 3D computer model of the left atrium was utilized to quantify thermal effects.
• PFA was simulated using a bipolar configuration with specific electrical boundary conditions.
• A monophasic waveform (100 μs pulse width, 1 s gap) was applied for 50 pulses at 1, 1.5, and 2 kV.

Main Results:

• Minimal esophageal temperature rise was observed at 1 kV (214.5 J).
• Temperatures reached 46.3°C and >62°C at 1.5 kV (570.3 J) and 2 kV (1.23 kJ) after a single pulse train, respectively.
• Repeated PFA applications may lead to significant temperature increases, especially with good tissue contact.

Conclusions:

• Thermal effects in PFA are dependent on total energy deposited, with peak voltage being a key determinant.
• Current PFA systems may induce collateral thermal injury with repeated use.
• Careful monitoring and adjustment of PFA parameters are crucial in clinical practice.