Abstract 2861: Comparison of Radiofrequency Ablation vs. Visually-Guided Laser Balloon Ablation in Achieving Chronic Pulmonary Vein Isolation in a Porcine Model
Background: During AF catheter ablation, achieving acute pulmonary vein isolation (PVI) is feasible in virtually all cases, but this does not always translate to chronic PVI. This study examined the feasiblitiy of achieving chronic PVI using either radiofrequency ablation (RFA) or ablation using a visually-guided laser balloon ablation catheter (BAC) in an in vivo porcine model.
Methods: In 14 normal pigs, the right superior PV was targeted for ablation: 4 RFA, 5 low-dose laser (5.5W), and 5 variable-dose laser (5.5–16.0W). Following transseptal puncture, a deflectable sheath was placed at the target vein. Baseline PV angiograms were performed to assess geometry and size. In animals undergoing RFA, circumferential ablation was performed using an externally irrigated catheter with 3D electroanatomical guidance. In animals undergoing laser ablation, the BAC was inflated at the PV ostium and an adjustable 30o arc of laser energy (980nm) was manipulated to create an encircling lesion set. PVI was ascertained using a circular mapping catheter. At 4 weeks, all animals were remapped to assess for persistent PVI and were subsequently sacrificed for gross examination.
Results: Acute PVI was achieved in 100% of PVs (4/4 RFA, 5/5 low-dose laser, 5/5 variable-dose laser). At 4 weeks, the PVs remained isolated in 3/4 (75%) PVs in the RFA arm, 3/5 (60%) in low-dose laser arm, and 5/5 (100%) in the variable-dose arm (Figure⇓). There were no significant PV stenoses. On gross examination at 4 weeks, there was no esophageal, phrenic nerve, or lung injury.
Conclusions: Acute PV isolation does not necessarily translate to chronic PV isolation; balloon ablation may improve the rate of chronic PV isolation.