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The lesion formation properties of a motorized rotational delivery (RAPID) mode, third-generation laser balloon (LB3) ablation compared to point-by-point laser ablation in patients with atrial fibrillation remain unclear.The purpose of this study was to assess lesion characteristics and thermodynamics in LB3 ablation with a RAPID modeChicken muscles were cauterized using LB3 in RAPID mode with 13 W and 15 W and 50% overlapped point-by-point fashion with 7 W/30 seconds, 8.5 W/20 seconds, 10 W/20 seconds, and 12 W/20 seconds. Lesion depth, width, and continuity were compared. Lesion continuity was classified by the visible gap degree categorized from 1 (perfect) to 3 (poor). Thermodynamics and maximum tissue temperatures were assessed under infrared thermographic monitoring. Fifteen and 5 lesions were evaluated per ablation protocol for measurement of lesion size and continuity and for thermographic assessment, respectively.Lesion depth and width were smaller in RAPID mode laser ablation than point-by-point laser ablation (RAPID mode LB3 ablation could provide fast, gapless, and acceptable lesion formation with thermal stacking and moderate tissue temperature rise.

An 83-year-old male with complete atrioventricular block underwent dual-chamber pacemaker implantation. Venography showed normal anatomy of the left axillary vein. Following sedation with intravenous propofol, local anesthesia, and skin incision, we punctured the left axillary vein on the first limb. However, the guidewire could not be advanced despite blood backflow after the initial puncture. On venography, left axillary vein on the first limb totally disappeared with dilated collaterals. We diagnosed axillary vein spasm and injected 1000 μg of intravenous nitroglycerin. After 15 min, repeated venography showed slight contrast flow in the axillary vein. We alternatively punctured the axillary vein on the second limb. However, the axillary vein was spasmodically occluded again. We considered the possibility that puncture of the right axillary vein could also result in venous spasm. Since the left cephalic vein was identified after waiting time, we partially cut down the left cephalic vein and inserted guidewires into the vein. The ventricular and atrial leads were successfully implanted through sheaths in the right ventricular septum and right atrial appendage, respectively. LEARNING OBJECTIVE: Pacemaker implantation complicated with puncture-related axillary vein spasm is challenging. Severe venous spasms refractory to waiting time or nitroglycerin sometimes require conversion of access site. However, the bail-out technique from ipsilateral access remains unclear. Cut-down technique of the ipsilateral cephalic vein is one alternative to manage severe axillary vein spasm refractory to nitroglycerin and waiting time.

Introduction: Cardiac sympathetic activity is involved in the initiation and maintenance of atrial fibrillation. A novel technique that evaluates the atrial accumulation of 123I-MIBG may be able to assess the atrial sympathetic innervation. The purpose of this study was to visually evaluate the modification of sympathetic innervation caused by multiple catheter ablations. Methods: The total study cohort comprised 32 patients with atrial fibrillation. 21 patients underwent only one ablation using a balloon catheter (cryoballoon in 10 patients; hot balloon in 11 patients) (group 1), while 11 patients underwent multiple radiofrequency catheter ablation procedures (three procedures in 6 patients; four procedures in 5 patients) (group 2). In all patients, the left atrial sympathetic activity was evaluated using MIBG images obtained using a novel solid-state whole-body scanner (VERITON). For local quantitative evaluation, the site with the strongest discrete MIBG accumulation was automatically recognized by the computer and compared in pre- and post-procedural images. Results: In all patients, the total left atrial MIBG accumulation value after ablation (6.64х10 4 ±1.65х10 4 PROPCNTS) was significantly lower than that before ablation (7.74х10 4 ±2.25х10 4 PROPCNTS, p=0.0289). At the site with the strongest discrete MIBG accumulation, the MIBG accumulation after ablation was decreased in 19 patients, unchanged in 9, increased in 3, and shifted in 1. The total left atrial MIBG accumulation value before ablation was significantly lower in group 2 (5.74х10 4 ±1.40х10 4 PROPCNTS) than group 1 (6.67х10 4 ±1.57х10 4 PROPCNTS, p=0.0485). Conclusions: The MIBG accumulation in the left atrium decreased after catheter ablation. Furthermore, preoperative evaluation revealed a significant decrease in MIBG accumulation after multiple ablation procedures. This suggests that multiple catheter ablation of the left atrium modifies the sympathetic innervation.