Body Size Modulates the Impact of the Dispersive Patch Position During Radiofrequency Cardiac Ablation

Area of Science:

• Cardiovascular Interventions
• Medical Device Technology
• Computational Modeling

Background:

• Cardiac radiofrequency (RF) ablation is a key treatment for arrhythmias.
• Dispersive patch (DP) placement relative to the ablation electrode may influence lesion size.
• The impact of patient body size on this effect is not well understood.

Purpose of the Study:

• To investigate how individual body size modulates the effect of dispersive patch positioning on cardiac RF ablation lesion size.
• To compare lesion sizes between concordant and discordant DP configurations across different body sizes.

Main Methods:

• Development of three computational models representing different body sizes (swine and human).
• Simulation of irrigated catheter ablation with a 30 W, 30 s pulse on the endocardial surface.
• Comparison of lesion sizes generated with anterior (concordant) and posterior (discordant) DP positions.

Main Results:

• Concordant DP positioning consistently resulted in significantly larger ablation lesions compared to discordant positioning.
• The magnitude of the difference in lesion size between concordant and discordant DP positions decreased with increasing body size.
• Observed differences ranged from 0.65 ± 0.08 mm in a 35 kg swine model to 0.51 ± 0.06 mm in a human model.

Conclusions:

• Patient body size has a modest influence on the effectiveness of DP positioning in RF ablation.
• The benefit of a concordant DP configuration on lesion size may be more significant in patients with smaller body volumes.
• These findings suggest personalized optimization of DP placement based on patient size may be beneficial.