VERY LOW ENERGY CARDIOVERSION FOR ATRIAL FIBRILLATION

极低能量心脏复律治疗心房颤动

• 批准号: 6402796
• 负责人: PATRICK D WOLF
• 金额: $ 26.95万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6402796
• 关键词: atrial fibrillation; biomedical device power system; biomedical equipment development; electronic pacemaker; epicardial mapping; heart electrical activity; implantable defibrillators; medical implant science; sheep

Internal atrial defibrillation is a successful therapy for the treatment of atrial fibrillation(AF). Current internal atrial defibrillators(IAD) use conventional defibrillation technology to deliver high energy shocks with a high likelihood of success. The applied shock strength of 3-10 Joules is above a patient's pain threshold and this limits the broad application of IAD therapy. A technology is proposed that utilizes multiple very low energy (less than .5J) shocks(VLES) with a low probability of first shock success but a high cumulative probability of conversion. A telemetry system will be implanted in an ovine model of AF. The combined animal model and telemetry system will be used as a test bed for VLES atrial cardioversion. The telemetry unit transmits 4 electrograms a distance of 10 meters and delivers continuous and programmed pacing by remote control. This system will be enhanced by adding pressure monitoring and VLES circuitry. It will be used 1) to characterize electrical remodeling and to track changes in infra-atrial pressure induced by the rapid pacing protocol and 2) to measure the energy that corresponds to a 5 percent level of success, and 3) to test three strategies for increasing the VLES probability of success. The three strategies are: 1) pre-VLES overdrive pacing 2) pre-VLES non-linear dynamics based pacing, and 3) use of class III antiarrhythmic drugs with VLES. Epicardial mapping will be used to identify the mechanism of VLES defibrillation and to characterize the effects of the 3 enhancement strategies. The work proposed in this grant will advance the science of remote testing in unanesthetized animals, will characterize the development of electrical modeling and myocardial pathology produced by rapid pacing in sheep, and will test a total of four strategies for very low energy atrial defibrillation. These advances will increase our understanding of the progression of AF and allow a successful therapy for this debilitating disease to be more broadly applied.

内部除颤是一种成功治疗心房颤动（AF）的疗法。 当前的内部心房除颤器（IAD）使用常规除颤技术，以很高的成功可能提供高能量冲击。 3-10焦耳的应用休克强度超过患者的疼痛阈值，这限制了IAD治疗的广泛应用。提出了一项技术，该技术利用了多个非常低的能量（小于.5J）冲击（VLE），其首次冲击成功率很低，但转化率的累积可能性很高。 遥测系统将植入AF的卵巢模型中。 组合的动物模型和遥测系统将用作VLES心房心脏的测试床。 遥测单元传输4个电图10米的距离，并通过遥控器进行连续和编程的起搏。 通过添加压力监控和VLE电路，将增强该系统。 它将用于1）来表征电气重塑并跟踪快速起搏协议引起的炎症的上压力的变化； 2）测量与成功水平5％的能量，以及3）测试三种策略，以增加成功的概率。 这三种策略是：1）预击不是速度的起搏2）基于非线性动力学的pre-vles pre-vles pre-drive state，3）使用III类抗心律失常药物与vles。 心外膜映射将用于确定VLE的除颤机制，并表征3种增强策略的影响。这项赠款中提出的工作将推进未经麻醉的动物中远程测试的科学，这将表征通过快速起搏在绵羊中产生的电模型和心肌病理学的发展，并将测试四种非常低能量的能量性心房除颤的策略。 这些进步将提高我们对AF进展的理解，并为这种使人衰弱的疾病的成功疗法提供更广泛的应用。