VIRTUAL TOOLS FOR CARDIAC VENTRICULAR REMODELING SURGERY

描述（由申请人提供）：心力衰竭在美国已达到流行病的比例，每年造成近50万人死亡。现在大多数心力衰竭病例是梗死诱导的心室重构的结果。由于缺乏一种行之有效的治疗方法，导致用于缓解心力衰竭患者的医疗和手术选择不断扩大。不幸的是，缺乏室壁运动或增厚（运动不能）可能会产生误导。另一方面，通过基于有限元（FE）方法的计算力学的力量，可以有信心地预测全局LV功能的任何变化（每搏输出量与舒张末期压）和局部力学（舒张末期和收缩末期肌纤维应力分布）当几何或负载条件或心肌材料特性时（舒张期僵硬度和收缩期收缩力）的变化，从而接近生物工程和演绎医学的目标。广泛的长期目标：开发一个易于使用的心肌材料特性软件工具（MMPST），通过FE模型模拟由于医疗和/或手术治疗引起的全局LV功能和局部力学变化的能力，使心血管疾病研究快速发展。具体目标：1。(A)开发并（B）验证MMPST，使心血管疾病研究人员能够轻松测量局部3-D心肌材料特性。确认将涉及Monte Carlo模拟和可变形硅胶体模（通过单一材料参数进行充分描述）。2.使用此MMPST：A.测量正常绵羊和患有运动不能或运动障碍性心肌梗死（MI）的绵羊体内局部3-D心肌材料特性。多巴酚丁胺将被给予羊与运动不能MI，以测试我们的假设，这些MI必须包含收缩肌细胞。B。在目标#2A中研究的心脏停搏和分离后，用我们的Vivitro伺服泵系统充盈LV，测量离体局部3-D心肌材料特性。此外，将对切除的运动不能和运动障碍MI进行双轴力学测试，以进一步验证我们的MMPST。

DESCRIPTION (provided by applicant): Heart failure has reached epidemic proportions in the United States and is responsible for nearly 500,000 deaths each year. The majority of heart failure cases is now the result of infarction-induced ventricular remodeling. The lack of a well-established effective treatment has lead to a continually expanding list of medical and surgical options for the palliation of heart failure patients. Unfortunately, the absence of ventricular wall motion or thickening (akinesis) can be misleading. On the other hand, through the power of computational mechanics based on the finite element (FE) method, it is possible to predict with confidence any changes in global LV function (stroke volume versus end-diastolic pressure) and regional mechanics (end-diastolic and end-systolic myofiber stress distributions) when geometric or loading conditions or myocardial material properties (diastolic stiffness and systolic contractility) are changed, thus approaching the objectives of bioengineering and deductive medicine. Broad, Long-Term Objective: Develop an easy-to-use Myocardial Material Property Software Tool (MMPST) that will enable rapid progress in cardiovascular disease research through the ability of FE models to simulate changes in global LV function and regional mechanics due to medical and/or surgical treatment. Specific Aims: 1. (A) Develop and (B) validate an MMPST that will enable cardiovascular disease researchers to easily measure regional 3-D myocardial material properties. Validation will involve both Monte Carlo simulations and a deformable silicon gel phantom that is well-described by a single material parameter. 2. Use this MMPST to: A. Measure in-vivo regional 3-D myocardial material properties in normal sheep and sheep with an akinetic or dyskinetic myocardial infarct (Ml). Dobutamine will be given to sheep with an akinetic Ml to test our hypothesis that these MIs must contain contracting myocytes. B. Measure ex-vivo regional 3-D myocardial material properties after arresting and isolating the hearts studied in Aim #2A and inflating the LV with our Vivitro servo-pump system. Additionally, biaxial mechanical testing will be performed on excised akinetic and dyskinetic MIs to further validate our MMPST.