ELECTRODE DESIGN FOR CARDIAC TACHYARRYTHMIA RF ABLATION

心脏快速心律失常射频消融的电极设计

• 批准号: 6389568
• 负责人: JOHN G WEBSTER
• 金额: $ 30.19万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6389568
• 关键词: atrial fibrillation; biomedical equipment development; biosensor device; clinical biomedical equipment; computed axial tomography; electrodes; endocardium; heart catheterization; heart electrical activity; heart surgery; phantom model; radiowave radiation; swine; tachycardia; thermography

DESCRIPTION (Adapted from Applicant's Abstract): The goal of this study is to optimize catheter design for the cure of atrial fibrillation and ventricular tachycardia by endocardial radiofrequency (RF) ablation. It is estimated that currently in the USA about 2 million people are affected by some form of atrial fibrillation. Also, each year about 200,000 patients are treated for ventricular tachycardia. Atrial fibrillation, although itself not fatal, is a frequent cause of stroke and is linked to a high degree of cardiovascular mortality. Ventricular tachycardia is the main cause of sudden cardiac death, affecting particularly patients suffering from myocardial infarction. To cure cardiac dysrhythmias, radiofrequency current flows through an electrode on a catheter in contact with the endocardium to ablate undesired arrhythmia substrates. This research will improve the electrodes and improve the procedure. In vitro tests on myocardium will yield physical parameters of electric conductivity, and thermal conduction, capacity, and heat convection variation throughout the endocardium. In vivo swine tests will improve accuracy of most parameters. The parameters will be used to improve a 3-dimensional finite element computer model that simulates the electric power deposited, the myocardial temperature rise and the volume and distribution of the 50 degree Celsius contour that defines the lesion boundary. Further in vitro and in vivo tests will confirm the accuracy of the model. The model will predict lesion volumes resulting from proposed new electrodes. These are (1) uniform current density electrodes that prevent hot spots, steam generation "popping" and coagulum formation; (2) noncontact electrodes that generate larger lesions; (3) needle electrodes that generate larger lesions; (4) long electrodes that generate linear lesions for curing atrial fibrillation; (5) balloon electrodes that permit large imprints; (6) cooled electrodes; and (7) other novel electrodes. The model will aid in the design of new electrodes. The model will also predict the lesion volume at each ablation site. These volume predictions will form guidelines for setting tip temperature to achieve desired lesion volume at each ablation site and thus enhance present ablation techniques.

描述（根据申请人的摘要改编）：这项研究的目的是 优化导管设计，以治愈心房颤动和心室 心内膜射频（RF）消融的心动过速。据估计 目前在美国，大约200万人受某种形式的房屋影响 纤颤。另外，每年约有200,000名患者接受治疗 心室心动过速。心房颤动，尽管本身并非致命，但 经常引起中风的原因，并与高度心血管有关 死亡。心室心动过速是心脏突然死亡的主要原因， 特别影响患有心肌梗塞的患者。 为了治愈心律不齐，射频电流流过电极 在与心内膜接触的导管上，以消除不想要的心律不齐 基材。这项研究将改善电极并改善 程序。对心肌的体外测试将产生物理参数 电导率以及热传导，容量和热对流 整个心内膜的变化。体内猪测试将提高准确性 大多数参数。这些参数将用于改善3维 有限元计算机模型模拟了沉积的电力， 心肌温度升高以及50度的体积和分布 定义病变边界的Celsius轮廓。进一步体外和体内 测试将确认模型的准确性。该模型将预测病变 提出的新电极产生的体积。这些是（1）均匀电流 防止热点的密度电极，蒸汽生成“弹出”和 凝血形成； （2）产生较大病变的非连接电极； （3） 产生较大病变的针电极； （4）长电极 产生线性病变，以固化房颤； （5）气球电极 那允许大量烙印； （6）冷却电极； （7）另一个小说 电极。该模型将有助于设计新电极。该模型将 还可以预测每个消融部位的病变体积。这些音量预测 将构成设定尖端温度以达到所需病变的指南 每个消融位点的体积，因此增强了融合技术。