Abstract 2544: Visually Guided Pulmonary Vein Isolation Using a Compliant Endoscopic Laser Balloon
Introduction: We tested the efficacy and safety of an endoscopic laser balloon ablation system (ELBAS) for achieving persistent pulmonary vein isolation (PVI) in a swine model.
Methods: PVI was performed in 8 swine using ELBAS and in 2 swine using a 4-mm RF ablator (Cntrl). The right superior (RS) PV was targeted for isolation and confirmed with a 15mm circular mapping catheter. For ELBAS, a compliant balloon was positioned at the RSPV antrum and inflated with deuterium oxide allowing endoscopic visualization of the PV. Light energy was delivered (5.5–16W/cm for 20 –30 secs) in overlapping 30° arcs around the PV. Cntrl ablation was performed with a 4-mm tip RF ablator (50 watts, 60°C, 50 secs) guided by 3D-mapping. Animals were survived for 1 month, restudied, and then sacrificed.
Results: All targeted PVs were successfully isolated acutely in 8 ELBAS and 2 CTRL swine. For ELBAS, 15±3 minutes of ablation/PV were required for complete PVI; overlapping lesions could be visualized during energy delivery as blanching of the endocardial surface (Figure⇓). For CTRL, 23±1 minutes of RF ablation were required for acute PVI. There was no acute change in PV flow after ablation (ELBAS pre vs, post 0.55 vs 0.58 m/s; CTRL 0.57 vs. 0.71 m/s). After 29±9 days, chronic PVI was present in 6/8 (75%) ELBAS PVs and 0/2 CTRL PVs. At sacrifice, ELBAS lesions consisted of smooth white circumferential lesions at the PV antrum. No PV stenosis or esophageal lesions were noted.
Conclusions: Antral PV isolation can be safely achieved with the compliant endoscopic laser balloon. Visual guidance appears to minimize gaps and chronic PV reconnection.