Preclinical evaluation of semi-automated laser ablation for pulmonary vein isolation: A comparative study

IntroductionVisually-guided laser balloon ablation (VGLA) currently requires careful manual rotation of the laser to create overlapping lesions. A novel semi-automated VGLA may reduce ablation times and lesion gaps. We aimed to compare semi-automated (SA) VGLA to that of manual (MN) VGLA. MethodsAcute: Nine swine underwent right superior pulmonary vein isolation (PVI) using either SA (n = 3, 13-18 W), MN (n = 3, 8.5-12 W), or radiofrequency (RF, n = 3, 25-40 W) and were killed acutely. Chronic: 16 swine, underwent PVI using either SA (n = 8, 15 W) or MN (n = 8, 10 W), and were survived for 1 month before being killed. All hearts were then submitted for pathological evaluation. ResultsAcute: PVI was successful in all 9/9 swine with lesion counts significantly lower in the SA arm (5.3 +/- 5.9, 33.7 +/- 10.0, and 28.0 +/- 4.4 in SA, MN, and RF arms; p = .007 for SA and MN). At necropsy, circumferentiality and transmurality were 98% and 94% in SA, 98% and 80% in MN, and 100% and 100% in RF arms. A single steam pop was noted on sectioning in the SA arm swine and occurred in the high dose (18 W) strategy. Chronic: PVI was acutely successful in 16/16 swine with no difference in PVI durability rates (62.5% vs. 75.0%), lesion transmurality (95.8 +/- 17.4% vs.91.9 +/- 25.9%), and circumferentiality (95.8 +/- 6.6% vs. 94.8 +/- 6.3%) between SA and MN arms. Catheter use time and lesion counts were lower in the SA arm compared to the MN arm (11.5 +/- 12.7 vs. 21.8 +/- 3.8 min, p = .046 and 4.8 +/- 3.83 vs. 35.4 +/- 4.4, p < .001). ConclusionMotor-assisted semi-automated laser balloon ablation can improve upon procedural efficiency by reducing ablation time.