Abstract：
BACKGROUND: Pulsed field ablation (PFA) is a novel, myocardial-selective, non-thermal ablation modality used to target cardiac arrhythmias. Although prompt EGM signal disappearance is observed immediately after PFA application in the pulmonary veins, whether this finding results in adequate transmural lesions is unknown.
OBJECTIVE: If application repetition and catheter-tissue contact impact on lesion formation during PFA.
METHODS: A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact-force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 hours in the vegetal model and over 6 hours in the porcine model.
RESULTS: Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 mm and 4.4 ± 1.3 mm, respectively (p =0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0±0.9 mm with no contact Vs. 5.4±1.4 mm with 30 g of force; p=.0001).
CONCLUSIONS: PFA delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA ablation are more related to PFA biophysics than mere EGM attenuation.
OBJECTIVE: If application repetition and catheter-tissue contact impact on lesion formation during PFA.
METHODS: A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact-force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 hours in the vegetal model and over 6 hours in the porcine model.
RESULTS: Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 mm and 4.4 ± 1.3 mm, respectively (p =0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0±0.9 mm with no contact Vs. 5.4±1.4 mm with 30 g of force; p=.0001).
CONCLUSIONS: PFA delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA ablation are more related to PFA biophysics than mere EGM attenuation.
摘要：
背景：脉冲场消融（PFA）是一种新颖的，心肌选择性，非热消融模式用于目标心律失常。尽管在肺静脉应用PFA后立即观察到EGM信号迅速消失，这一发现是否导致足够的透壁性病变尚不清楚.
目的：如果重复应用和导管-组织接触对PFA期间的病变形成有影响。
方法：使用环形PFA导管以各种水平的接触力反复施加能量。使用台式植物马铃薯模型和跳动的心室心肌模型来评估重复应用的影响，接触力,和导管在连续性和病变深度上重新定位。在植物模型中,病变发展超过18小时,在猪模型中超过6小时。
结果：发现病变的形成依赖于重复应用和接触。在猪的脑室,单个和多个堆叠的应用导致3.5±0.7mm和4.4±1.3mm的病变深度，分别(p=0.002)。此外，导管与组织的接触越大,在植物模型中，病变越连续，越深（1.0±0.9mm，无接触Vs。5.4±1.4mm，力30g；p=.0001）。
结论：通过圆形导管递送的PFA显示，重复和导管接触均独立导致较深的病变形成。这些发现表明，有效PFA消融的终点与PFA生物物理学有关，而不仅仅是EGM衰减。
目的：如果重复应用和导管-组织接触对PFA期间的病变形成有影响。
方法：使用环形PFA导管以各种水平的接触力反复施加能量。使用台式植物马铃薯模型和跳动的心室心肌模型来评估重复应用的影响，接触力,和导管在连续性和病变深度上重新定位。在植物模型中,病变发展超过18小时,在猪模型中超过6小时。
结果：发现病变的形成依赖于重复应用和接触。在猪的脑室,单个和多个堆叠的应用导致3.5±0.7mm和4.4±1.3mm的病变深度，分别(p=0.002)。此外，导管与组织的接触越大,在植物模型中，病变越连续，越深（1.0±0.9mm，无接触Vs。5.4±1.4mm，力30g；p=.0001）。
结论：通过圆形导管递送的PFA显示，重复和导管接触均独立导致较深的病变形成。这些发现表明，有效PFA消融的终点与PFA生物物理学有关，而不仅仅是EGM衰减。
