LV SV using Admittance for Hemodynamically Unstable Arrhythmia Detection

使用导纳进行 LV SV 检测血流动力学不稳定心律失常

• 批准号: 9250203
• 负责人: MARC David FELDMAN
• 金额: $ 61.67万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9250203
• 关键词: Acute; Algorithms; Animals; Area; Arrhythmia; Back; Blood Pressure; Blood Volume; Canis familiaris; Cardiac; Cessation of life; Chronic; Cicatrix; Clinical; Data; Detection; Development; Devices; Electric Countershock; Electrocardiogram; Epicardium; Fibrosis; Fright; Goals; Grant; Health Personnel; Heart; Heart failure; Human; Hypotension; Implant; Implantable Defibrillators; Laboratories; Lateral; Lead; Letters; Life; Measurement; Medical; Medical Device; Modeling; Monitor; Morphology; Myocardial; Myocardium; Operative Surgical Procedures; Outpatients; Pacemakers; Patients; Physicians; Play; Prevention; Problem Solving; Publishing; Quality of life; Recording of previous events; Research; Shock; Signal Transduction; Sinus; Stroke Volume; Tachycardia; Technology; Testing; Texas; Time; United States National Institutes of Health; Universities; Veins; Ventricular; Ventricular Arrhythmia; Width; Work; base; cardiac resynchronization therapy; cost; emotional trauma; experience; falls; hemodynamics; human disease; implantable device; implantation; improved; interest; material transfer agreement; miniaturize; mortality; new technology; prevent; public health relevance; sudden cardiac death; voltage

 DESCRIPTION (provided by applicant): Implantable cardioverter defibrillators (ICDs) are medical devices proven to prevent sudden cardiac death due to ventricular arrhythmias. Their decisions are based solely upon the intra--‐cardiac ECG. This is incomplete information since up to 1/3 of patients experience an "inappropriate" shock within the first 1-3 years of receiving the implant. Receiving a shock is associated with increased mortality as well as emotional trauma. In contrast, physicians determine whether to shock or medically convert a patient out of a rapid rhythm by determining if the arrhythmia is hemodynamically unstable or stable. An unstable arrhythmia is identified by decreased forward stroke volume (SV) and resultant low blood pressure (BP). A stable arrhythmia is identified by a forward SV or resultant BP close to the patient's baseline. It would be ideal to have beat‐by-beat SV available to the generator to assist in the determination of hemodynamic stability. Our group has developed a new technology which can utilize pre-existing ICD and bi-ventricular pacing leads to input current between the RV septum and lateral LV vein, take the returning voltage signal, remove the myocardial component of this signal, and derive LV SV. Although we have validated the technology in acute large animal studies (see preliminary data), we have not validated the approach in chronic large animals which will require (a) demonstrating our technology is successful over months of time in a large animal heart failure model as lead fibrosis occurs, (b) developing an algorithm to incorporate beat-by-beat SV into current ECG detection algorithms, and (c) proving that the platform works in diseased human hearts. To achieve these goals, we propose the following specific aims: Aim 1 - Purchase and validate a miniaturized, low power implantable version of our admittance circuit. Aim 2 - Demonstrate that our admittance circuit developed for chronic implantation can successfully classify arrhythmias into those that can reduce SV, and those that do not in a chronic pacing induced canine model of heart failure. This will (a) determine the impact of lead fibrosis to the myocardium on the drift profile of the admittance signal, and (b) demonstrate that admittance SV will fall as echo SV and BP fall during the induction of VT, vfib, SVT and afib. Conversely, in hemodynamically stable arrhythmias defined by echo SV and BP, admittance SV will successfully mirror these same findings. The signals will be recorded for use in SA 3. Aim 3 - Develop algorithms that can utilize steady state SV information in conjunction with traditional ECG rate, rhythm, and morphology algorithms to increase the accuracy of generator decisions to either deliver therapy to hemodynamically unstable arrhythmias, or withhold therapy from a stable hemodynamic arrhythmia. These algorithms will be tested in an iterative fashion in conjunction with SA 2 by playing back the recorded ECG and admittance SV signals to an AICD on the laboratory bench. Aim 4 - Validate admittance SV measurement in patients undergoing battery changes with chronic scarred-in Cardiac Resynchronization Therapy-Defibrillation (CRT‐D) leads.

 描述（由申请人提供）：植入式心律转复除颤器（ICD）是经证明可预防室性心律失常导致的心源性猝死的医疗器械。他们的决定完全基于心内ECG。这是不完整的信息，因为多达1 - 3的患者在植入后的前1-3年内经历了“不适当”的电击。接受电击与死亡率增加以及情感创伤有关。相反，医生通过确定心律失常在血流动力学上是不稳定还是稳定来确定是否电击或医学上将患者从快速心律转换出来。不稳定性心律失常通过减少的前向每搏输出量（SV）和由此产生的低血压（BP）来识别。稳定性心律失常通过接近患者基线的前向SV或合成BP来识别。理想的情况是，消融仪可以使用逐搏SV，以帮助确定血流动力学稳定性。 我们的团队开发了一种新技术，该技术可以利用现有的ICD和双心室起搏电极导线在RV间隔和LV侧静脉之间输入电流，获取返回电压信号，去除该信号的心肌成分，并导出LV SV。虽然我们已经在急性大型动物研究中验证了该技术（见初步数据），我们尚未在慢性大型动物中验证该方法，这将需要（a）证明我们的技术在大型动物心力衰竭模型中随着导线纤维化的发生在数月内是成功的，（B）开发一种算法以将逐搏SV结合到当前ECG检测算法中，以及（c）证明该平台在患病的人类心脏中起作用。为实现这些目标，我们提出以下具体目标： 目的1 -购买和验证一个小型化，低功耗植入式版本的导纳电路。 目的2 -证明我们开发的用于慢性植入的导纳电路可以成功地将心律失常分类为可以减少SV的心律失常和在慢性起搏诱导的心力衰竭犬模型中不能减少SV的心律失常。这将（a）确定电极导线纤维化对心肌对导纳信号漂移曲线的影响，以及（B）证明在VT、vfib、SVT和afib诱导期间，导纳SV将随着回波SV和BP下降而下降。相反，在由回波SV和BP定义的血流动力学稳定的心律失常中，导纳SV将成功地反映这些相同的结果。将记录这些信号，以便在SA 3中使用。 目标3 -开发可利用稳态SV信息结合传统ECG速率、节律和形态算法的算法，以提高发生器决策的准确性，从而对血流动力学不稳定的心律失常进行治疗，或对稳定的血流动力学心律失常停止治疗。这些算法将通过将记录的ECG和导纳SV信号回放到实验室工作台上的AICD，以迭代方式结合SA 2进行测试。 目的：在使用慢性瘢痕心脏复苏治疗-除颤（CRT-D）电极导线进行电池更换的患者中测量4 -kHz导纳SV。