Noninvasive conduction mapping using Electromechanical Wave Imaging

描述（由申请人提供）：心源性猝死是由心脏功能突然丧失（心脏骤停）引起的。受害者可能患有心脏病，也可能没有。每年约有31万人死于冠心病（CHD），而没有住院或进入急诊室。这大约是冠心病死亡人数的一半。每天约850名美国人，即每两分钟约1名美国人。尽管死亡人数巨大，但目前临床上还没有一种成像方式可以直接和无创地绘制整个心脏的传导波或异常或疾病时的传导波。因此，在衰竭的心脏中进行无创图像传导的能力将显著改善这种疾病的诊断、治疗和管理。在这项研究中，我们的目标是开发和评估一种新的成像方式，即机电波成像（EWI），它可以在非常高的帧速率下同时绘制心脏的电和机械功能，无论是否存在疾病。因此，我们提议证明EWI技术可以可靠地绘制心脏内的传导波，因为它沿着间隔壁传播并进入左心室和右心室壁；在正常和病态的心脏中。为了评估该技术的性能，我们将使用一种新的机电模型，该模型将被扩展和修改以适应本研究的目标。因此，提出的研究的具体目的是：1)使用机电犬仿真模型优化EWI估计；2)在体评估导通正常、束支阻滞犬的EWI表现；3)利用犬类仿真模型验证在体机电波成像。因此，本研究的结果有望产生一种新的无创心脏传导测绘成像方法，与标准超声心动图相比，没有或很少增加成本，同时丰富心脏机电耦合的计算模型。这种R21应用的高影响在于，相同的成像模式可以很容易地集成到任何商业超声心动图系统中，以便立即转化为临床。此外，它还可以安全和无创地应用于任何诊断方法，如心电图和超声心动图，或监测治疗技术，如心脏再同步化治疗（CRT）和射频（RF）消融，用于检测和治疗广泛的心血管疾病，或条件，如心律失常和心力衰竭。高风险的部分与这样一个事实有关：将心脏的电子功能与机械功能结合起来可能是一项艰巨的任务，但考虑到团队的组建和初步结果的可用性，这是可行的挑战。

DESCRIPTION (provided by applicant): Sudden cardiac death results from an abrupt loss of heart function (cardiac arrest). The victim may or may not have diagnosed heart disease. About 310,000 people a year die of coronary heart disease (CHD) without being hospitalized or admitted to an emergency room. This is about half of all deaths from CHD . about 850 Americans each day, i.e., about 1 American every 2 minutes. Despite this enormous death toll, there is currently no imaging modality in the clinic that can directly and noninvasively map the conduction wave in the entire heart or its disruption in the presence of an abnormality or disease. The ability to non-invasively image conduction in the failing heart would thus significantly improve the diagnosis, treatment, and management of this condition. In this study, our objective is to develop and evaluate a novel imaging modality, Electromechanical Wave Imaging (EWI) that can simultaneously map, at very high frame rates, both the electrical and mechanical cardiac function, at both the presence and absence of disease. We propose thus to demonstrate that the EWI technique can reliably map the conduction wave in the heart as it propagates along the septal wall and into the left and right ventricular walls; in both normal and pathological hearts. To assess the performance of the technique, we will use a novel electromechanical model, which will be extended and modified to fit the objectives of this study. The specific aims of the proposed study are thus to: 1) optimize the EWI estimates using an electromechanical canine simulation model; 2) assess the performance of EWI in dogs with normal conduction and bundle branch block in vivo; and 3) validate the electromechanical wave imaged in vivo using the canine simulation model. As a result, the outcomes of this study are expected to yield a novel imaging methodology for noninvasive conduction mapping of the heart, at no or little additional cost to that of standard echocardiography, as well as simultaneously enrich the computation models of the electromechanical coupling of the heart. The high impact of this R21 application lies in the fact that the same imaging modality can easily be integrated into any commercial echocardiography system for immediate translation to the clinic. Furthermore, it can also be applied safely and noninvasively in conjunction with any diagnostic method, such as electrocardiography and echocardiography or, monitoring of therapeutic techniques, such as Cardiac Resynchronization Therapy (CRT) and radio-frequency (RF) ablation, for the detection and treatment of a wide range of cardiovascular diseases, or conditions, such as arrhythmias and heart failure. The high risk component is associated with the fact that tying the electrical with the mechanical function of the heart can be a formidable, but feasible given the team assembled and preliminary results available, challenge. PUBLIC HEALTH RELEVANCE STATEMENT: About 310,000 people a year die of coronary heart disease without being hospitalized or admitted to an emergency room. This is about 1 American every 2 minutes. Despite this enormous death toll, there is currently no imaging modality that can display the conduction wave in the entire heart in the clinic. Our objective is to develop and evaluate a novel imaging modality, Electromechanical Wave Imaging (EWI) that can noninvasively map the cardiac conduction, at both the presence and absence of disease.