ELECTRODE DESIGN FOR CARDIAC TACHYARRHYTHMIA RF ABLATION

用于心律失常射频消融的电极设计

• 批准号: 2771514
• 负责人: JOHN G WEBSTER
• 金额: $ 24.13万
• 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 2000-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2771514
• 关键词: atrial fibrillation; biomedical equipment development; biosensor device; clinical biomedical equipment; computed axial tomography; electric field; electrodes; heart catheterization; heart electrical activity; human data; phantom model; radiowave radiation; swine; tachycardia; thermography; thorax

This study will optimize catheter design for the cure of atrial fibrillation and ventricular tachycardia by radiofrequency (RF) ablation. In the USA about 2 million people are affected by some form of atrial fibrillation. 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 with myocardial infarction. Studies confirm the superiority of catheter ablation in the cure of monomorphic ventricular tachycardias. To cure atrial fibrillation, the physician would have to create, by RF ablation, long, thin lesions along trajectories similar to those postulated by the MAZE or Corridor procedures. For the cure of ventricular tachycardia, wide and deep lesions created by RF ablation were found therapeutically successful. This study will develop complex finite element (FE) models and perform experimental tests to optimize the design of ablation catheters capable of producing long thin lesions for the cure of atrial fibrillation (AFIB). It will also develop complex numerical models and perform experimental tests to optimize the design of ablation catheters capable of creating wide and deep lesions for the cure of ventricular tachycardia (VT). This research will include creation of maps of electrical and thermal properties of the organs lying in the thorax, for the range of voltages, current densities and temperatures applicable to RF ablation. These data will be used to create realistic and complex FE models for electrical- thermal FE analyses. Acquisition of a collection of CT scans of swine thoraxes will be used for developing correct geometry for FE models for the swine studies. Improvement of CT scans of human thoraxes, such as subsets for: (a) normal men; (b) normal women; (c) obese men; (d) obese women; (e) children, will be used to develop geometrically correct FE models for the human studies. These models will be used to research optimal ablation catheter design for the therapy of AFIB and VT. Experimental tests will validate temperature and electric field distributions predicted by the swine FE models. Simulations will find the optimal catheter design for the cure of AFIB and VT. These tests will determine: (a) optimal electrode/catheter geometry; (b) optimal placement of inner temperature sensors for the purpose of efficient temperature- controlled RF ablation; (c) optimal power application and ablation procedure duration. These findings will clarify the electrical-thermal response of the catheter-tissue system during RF ablation. Experimental tests on swine will verify the models. Recommendations for optimal ablation catheter design for human use having applications for the therapy of AFIB and VT will be disseminated.

这项研究将优化导管设计以治愈房屋 射频（RF）消融的纤颤和心室心动过速。 在美国，大约200万人受某种形式的房屋影响 纤颤。每年约有200,000名患者接受治疗 心室心动过速。心房颤动，尽管本身不是致命的，但 是中风的经常原因，与高度有关 心血管死亡率。心室心动过速是 心脏猝死，特别影响心肌患者 梗塞。 研究证实了导管消融在治疗中的优势 单态性心脏心动过速。为了治愈房颤， 医师将不得不通过RF消融，沿着长而薄的病变创造 类似于迷宫或走廊假设的轨迹 程序。为了治愈心室心动过速，宽而深 发现由RF消融产生的病变在治疗上成功。 这项研究将开发复杂的有限元（FE）模型并执行 实验测试以优化能够消融导管的设计 产生长薄病变以治愈房颤 （AFIB）。它还将开发复杂的数值模型并执行 实验测试以优化能够消融导管的设计 为治愈心室心动过速的宽阔和深层病变 （VT）。 这项研究将包括创建电气和热图的地图 胸部中的器官的特性，用于电压范围 当前的密度和适用于RF消融的温度。这些数据 将用于创建现实且复杂的电气模型 热铁分析。获取一系列CT扫描的猪 胸部将用于为Fe模型开发正确的几何形状 猪研究。改进人类胸部的CT扫描，例如 子集：（a）普通男人； （b）正常妇女； （c）肥胖男人； （d）肥胖 女性; （e）儿童将用于发展几何正确的Fe 人类研究的模型。这些模型将用于研究 用于治疗AFIB和VT治疗的最佳消融导管设计。 实验测试将验证温度和电场 猪Fe模型预测的分布。模拟会发现 用于治疗AFIB和VT的最佳导管设计。这些测试将 确定：（a）最佳电极/导管几何形状； （b）最佳位置 内部温度传感器的目的是有效的温度 控制的RF消融； （c）最佳功率应用和消融 程序持续时间。这些发现将阐明电气热 RF消融过程中导管组织系统的响应。实验 猪的测试将验证模型。最佳建议 用于人类使用的消融导管设计具有应用 AFIB和VT的治疗将被传播。