Excitation Recovery on the Surface Myocardium After Shorter but Not Nominal Time Radiofrequency Application Using an Open Irrigation Catheter
Excitation Recovery on the Surface Myocardium After Shorter but Not Nominal Time Radiofrequency Application Using an Open Irrigation Catheter
复制标题
使用开放式冲洗导管进行较短但非标称时间射频应用后心肌表面的兴奋恢复
DOI：
10.1161/circep.121.010392
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Saitoh O
中科院分区：
文献类型：
--
作者：
Chinushi M;Saitoh O
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When using an irrigation catheter, short applica-tion time ablation may create reversible injury on the well-cooled myocardial surface. 1 This study approved by our subcommittee was in compliance with the guidelines of the US National Institutes of Health for the Care and Use of Laboratory Animals. The data that support the findings are available from the corresponding author. Porcine hearts were obtained after being killed for food at a meat processing plant and transferred, with Cardioplegia injected into both coronary arteries on site. The right coronary artery was exposed and the right ventricular segment was perfused with warmed Tyrode’s solution to resume spontaneous beating. Each myocardium was placed on a tray in the experimental bath containing Tyrode’s solution, circulated by a pump and temperature controlled at 37 C. Two-needle electrodes were inserted vertically into the myocardium. Each needle carried 8 polyurethane-coated copper wire electrodes, 0.2 mm in diameter, 1 mm apart (first at distal and eighth at proximal), and the most proximal electrode was located just under the endocardial surface (Figure). To measure the local excitation thresholds, unipolar pacing (100 ppm and 0.1 ms width) was performed between each electrode of the needle and a ground electrode in the bath. For ablation, both needle electrodes were extracted from the myocardium, and an open irrigation catheter (Cool Flex, Abbott. Irvine, CA) was vertically positioned with a contact force of 10 g on the site where one of the needle electrodes had been inserted. Using a generator (1500T12, Abbott, Irvine, CA), radiofrequency ablation (40 W) was attempted on 10 myocardium in the40-second group and the other 10 in the 15-second group. The other site was not ablated and the 2-needle electrodes were reinserted after the ablation. Fifteensecond radiofrequency ablation was also attempted at 10 sites in another 5 myocardium using a nonirrigation catheter (Therapy 4 mm, Abbott, Irvine, CA).