Nonthermal Irreversible Electroporation to the Esophagus: Evaluation of Acute and Long‐Term Pathological Effects in a Rabbit Model

Background Esophageal ulceration and fistula are severe complications of pulmonary vein isolation using thermal ablation. Nonthermal irreversible electroporation (NTIRE) is a promising new technology for pulmonary vein isolation in patients with atrial fibrillation. NTIRE ablation technology has been used to treat atrial fibrillation; however, the effects of NTIRE on esophageal tissue have not been clearly described. Methods and Results A typical NTIRE electrical protocol was directly applied to esophagi in 84 New Zealand rabbits. Finite element modeling and histological analysis with 120 slices were used to analyze electric field intensity distribution and subsequent tissue changes. A parameter combination of 2000 V/cm multiplied by 90 pulses output is determined to be an effective ablation parameters combination. Within 16 weeks after ablation, no obvious lumen stenosis, epithelial erythema, erosion, ulcer, or fistula was observed in the esophageal tissue. NTIRE effectively results in esophageal cell ablation to death, and subsequently, signs of recovery gradually appear: creeping replacement and regeneration of epithelial basal cells, repair and regeneration of muscle cells, structural remodeling of the muscle layer, and finally the restoration of clear anatomical structures in all layers. Conclusions Monophasic, bipolar NTIRE delivered using plate electrodes in a novel esophageal injury model demonstrates no histopathologic changes to the esophagus at 16 weeks. Data of this study suggest that electroporation ablation is a safe modality for pulsed electroporation ablation near the esophagus.

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Pulmonary vein isolation by irreversible electroporation: an efficacy and safety study in 20 patients with atrial fibrillation

EP Europace ◽

10.1093/europace/euab116.095 ◽

2021 ◽

Vol 23 (Supplement_3) ◽

Author(s):

P Loh ◽

MHA Groen ◽

K Taha ◽

FHM Wittkampf ◽

PA Doevendans ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Conscious Sedation ◽

Brain Mri ◽

Irreversible Electroporation ◽

Cerebral Lesions ◽

Private Company ◽

Funding Sources ◽

Before And After

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Abbott Background Irreversible electroporation (IRE) is a promising new non-thermal ablation technology for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). First in human studies demonstrated the feasibility and safety of IRE PVI. Objective Further investigate the safety of IRE PVI. Methods Twenty patients with symptomatic AF underwent IRE PVI under conscious sedation. Oral anticoagulation was uninterrupted and heparin was administered to maintain activated clotting time at 300-350 seconds. Non-arcing, non-barotraumatic 6 ms, 200 J IRE applications were delivered via a custom non-steerable 8 F, 14-polar circular IRE ablation catheter with a variable hoop diameter (16-27 mm). Voltage mapping of the left atrium and the PVs was performed before and after ablation with a conventional circular mapping catheter. For both catheters a single transseptal access (8 F introducer, Agilis NxTTM) was used. Adenosine testing was performed after a 30-minute waiting period. On day 1 after ablation, patients underwent esophagoscopy and brain MRI (DWI/FLAIR). If abnormalities were detected, examinations were repeated in due time. Results In 20 patients, all 80 PVs could be successfully isolated with a mean of 11,8 ± 1,4 IRE applications per patient. Average time from first to last IRE application was 22 ± 5 minutes, total procedure duration was 107 ± 13 minutes and total fluoroscopy time was 23 ± 5 minutes. One PV reconnection occurred during adenosine testing, re-isolation was achieved with 2 additional IRE pulses. No periprocedural complications were observed. Brain MRI on day 1 after ablation showed punctate asymptomatic lesions in 3/20 patients (15%). At follow-up MRI the lesion disappeared in 1 patient while in the other 2 patients 1 lesion persisted. Esophagoscopy on day 1 showed an asymptomatic esophageal lesion in 1/20 patients (5%), at repeat esophagoscopy on day 22 the lesion had resolved completely. Conclusion Acute electrical PV isolation could be achieved safely and rapidly by IRE ablation under conscious sedation in 20 patients with symptomatic AF. Acute silent cerebral lesions were detected in 3/20 patients (15%) and may be due to ablation or to changes of therapeutic and diagnostic catheters over a single transseptal access.

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Characteristics of Esophageal Injury in Ablation of Atrial Fibrillation Using a High-Power Short-Duration Setting

Circulation Arrhythmia and Electrophysiology ◽

10.1161/circep.120.008602 ◽

2020 ◽

Vol 13 (10) ◽

Cited By ~ 1

Author(s):

Takashi Kaneshiro ◽

Masashi Kamioka ◽

Naoko Hijioka ◽

Shinya Yamada ◽

Tetsuro Yokokawa ◽

...

Keyword(s):

Atrial Fibrillation ◽

Left Atrium ◽

Pulmonary Vein ◽

Short Duration ◽

Pulmonary Vein Isolation ◽

High Power ◽

Thermal Injury ◽

Low Voltage ◽

Conventional Group ◽

Esophageal Injury

Background: The mechanism of esophageal thermal injury (ETI; esophageal mucosal injury and periesophageal nerve injury leading to gastric hypomotility) remains unknown when using a high-power short-duration (HP-SD) setting. This study sought to evaluate the characteristics of esophageal injuries in atrial fibrillation ablation using a HP-SD setting. Methods: After exclusion of 5 patients with their esophagus at the right portion of left atrium and 21 patients with additional ablations such as box isolation and low voltage area ablation in left atrium posterior wall, 271 consecutive patients (62±10 years, 56 women) who underwent pulmonary vein isolation by radiofrequency catheter ablation were analyzed. In the 101 patients, a HP-SD setting at 45 to 50 W with an Ablation Index module was used (HP-SD group). In the remaining 170 patients before introduction of the HP-SD setting, a conventional power setting of 20 to 30 W with contact force monitoring was used (conventional group). We performed esophagogastroduodenoscopy after pulmonary vein isolation in all patients and investigated the incidence and characteristics of ETI. Results: Although the incidence of ETI was significantly higher in the HP-SD group compared with the conventional group (37% versus 22%, P =0.011), the prevalence of esophageal lesions did not differ between the groups (7% versus 8%). Multivariate logistic regression analysis revealed that the use of the HP-SD setting (odds ratio, 6.09, P <0.001), and the parameters that suggest anatomic proximity surrounding the esophagus, were independent predictors of ETI. However, the majority of ETI in the HP-SD group was gastric hypomotility, and the thermal injury was limited to the shallow layer of the periesophageal wall using the HP-SD setting. Conclusions: Although the use of the HP-SD setting was a strong predictor of ETI, it could avoid deeper thermal injuries that reach the esophageal mucosal layer.

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