Mackey S, Thornton L, He D S, Marcus F I, Lampe L F
Department of Medicine, University of Arizona College of Medicine, Tucson, USA.
Pacing Clin Electrophysiol. 1996 Jul;19(7):1042-8. doi: 10.1111/j.1540-8159.1996.tb03411.x.
Delivery of radiofrequency (RF) energy from the distal tip of electrophysiology catheters produces lesions that may be too small to ablate arrhythmogenic sites during a single application of RF energy. To produce larger lesions, we delivered RF energy via a quadripolar catheter in which all four electrodes were connected in unipolar fashion. The catheter (Webster Labs) had a 4-mm tip, 2-mm ring electrodes, and 2-mm interelectrode distance. Lesion size was compared using RF energy delivered in a multipolar configuration with that delivered only to the distal tip using fresh bovine ventricular tissue. In vivo, RF lesions were made in dogs using the distal tip as well as all four poles of the same catheter inserted percutaneously. RF energy was delivered using a constant voltage at a frequency of 400 kHz. Preliminary experiments were conducted to determine the maximum power deliverable without coagulation using each electrode configuration. The use of simultaneous multipolar RF ablation produced significantly larger lesions both in vitro and in vivo. The length of the lesion was increased by a factor of approximately 2 in both the in vitro and in vivo experiments. There was a trend toward an increasing depth of the lesion by simultaneously applying RF energy to all four electrodes. Lesion width was significantly increased in the in vivo studies. We concluded that simultaneous multipolar delivery of RF energy produces larger lesions than can be obtained with delivery of RF energy to the distal tip alone. This technique may offer a means of increasing lesion size, leading to a decrease in the number of applications of RF energy necessary for ablation of arrhythmias.
从电生理导管的远端尖端输送射频（RF）能量所产生的损伤可能过小，以至于在单次施加RF能量时无法消融致心律失常部位。为了产生更大的损伤，我们通过四极导管输送RF能量，其中所有四个电极均以单极方式连接。该导管（韦伯斯特实验室）的尖端为4毫米，环形电极直径为2毫米，电极间距为2毫米。使用多极配置输送的RF能量与仅输送到远端尖端的RF能量，在新鲜牛心室组织上比较损伤大小。在体内，使用同一导管的远端尖端以及经皮插入的所有四个电极在犬身上制造RF损伤。以400 kHz的频率使用恒定电压输送RF能量。进行了初步实验以确定每种电极配置在不发生凝血的情况下可输送的最大功率。同时使用多极RF消融在体外和体内均产生了明显更大的损伤。在体外和体内实验中，损伤长度均增加了约2倍。通过同时向所有四个电极施加RF能量，损伤深度有增加的趋势。在体内研究中，损伤宽度显著增加。我们得出结论，与仅向远端尖端输送RF能量相比，同时多极输送RF能量会产生更大的损伤。该技术可能提供一种增加损伤大小的方法，从而减少消融心律失常所需的RF能量施加次数。
