Mitigating Iatrogenic Air Entrainment During Pulsed Field Ablation: A Comparative Study of a Novel Submerged-Entry...

Systemic air embolism remains a critical risk during left atrial procedures, particularly during the frequent exchanges required in pulsed field ablation (PFA). In this study we evaluated the air intrusion patterns using the VARIPULSE^TM PFA system with a relatively small sheath lumen, and assessed a custom-made "Adapter Sink" designed to eliminate air entry.

Using an ex vivo water-tank model, we monitored the insertion of the VARIPULSE^TM catheter through an 8.5Fr CARTO VIZIGO® Bi-Directional Guiding Sheath. Three protocols were compared: (1) standard insertion without suction, (2) insertion with active manual suction, and (3) insertion using the custom Adapter Sink (submerged entry). Air volume was quantified across 10 trials per group. Baseline insertion (no suction) consistently introduced visible small air bubbles, although manual suction by an assistant reduced the bubbles' volume and frequency significantly. In contrast, the Adapter Sink group had zero air intrusion by operator alone without assistance, providing a complete physical barrier against atmospheric air.

Even with smaller profile sheaths such as the 8.5Fr VIZIGO®, a continuous saline drip may be insufficient. The Adapter Sink effectively minimized air intrusion and optimized manpower by requiring only a single operator, unlike manual suction, which relies on an assistant. However, further in vivo or clinical studies are warranted to validate the feasibility of our setup under physiological conditions.