SURGERY FOR ACUTE MYOCARDIAL INFARCTION

急性心肌梗死的手术

• 批准号: 2218122
• 负责人: L HENRY EDMUNDS
• 金额: $ 34.14万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2218122
• 关键词: acute disease /disorder; combination therapy; coronary occlusion /thrombosis; echocardiography; glutaraldehyde; heart aneurysm; heart disorder chemotherapy; heart surgery; heart ventricle; hemodynamics; injection /infusion; magnetic resonance imaging; mitral valve insufficiency; myocardial infarct sizing; myocardial infarction; nonhuman therapy evaluation; oral administration; oxygen consumption; peptidyl dipeptidase A; plastics; resin; sheep

This proposal seeks to develop new surgical procedures based upon knowledge of changes in left ventricular (LV) mechanics, material properties and geometric shape for acute myocardial infarctions (AMI) of different, specific ventricular locations. The project tests a central hypothesis: that surgical interventions can favorably alter ventricular remodeling or the effects of remodeling after AMI. The project focuses on ischemic mitral regurgitation (MR), antero-apical LV aneurysm and large antero-apical AMI. The proposed work will utilize our well-developed sheep models of antero- apical myocardial infarctions of 22 and 30% of the LV mass; 22% infarctions that produce ischemic MR involving either the anterior or posterior papillary muscle; acute, severe MR after 30% infarctions; and posterior infarctions that do not produce aneurysm or MR. The LV will be imaged using four techniques; sonomicrometry array localization (SAL), quantitative echocardiography, serial ventriculography and cine magnetic resonance imaging. Material properties of infarcted, border zone and remote myocardium will be assessed using our biaxial stress-extension apparatus. Changes in the interrelationships of mitral valve subunits (i.e., annulus, papillary muscle, adjacent ventricular wall) after coronary artery occlusion produces ischemic MR; the components of the valve itself do not change (e.g., leaflets, chordae). We will use SAL to track these changes and devise reparative operations to reverse the changes and restore mitral valvular competence. We will use multiple imaging techniques, biaxial stress-extension studies, and different infarction models to describe the remodeling process after LV infarctions of specific size and location. Our goal is to quantitate regional strains, calculate regional stresses, and to observe how these are redistributed during remodeling. We will assess LV mechanics and correlate these with hemodynamic measurements after plication or patching antero-apical LV aneurysms. We will evaluate both an inert, felt patch and a patch of viable, nonstimulated skeletal muscle. We will attempt to modify the material properties of antero-apical LV infarcts to reduce ventricular deformation and to improve ventricular performance by modifying the material properties of the infarct by reperfusion, an angiotensin converting enzyme inhibitor, and by direct injection of a stiffening material. The heart is a pump. These studies are designed to develop surgical interventions to improve early and long-term ventricular performance after AMI.

该建议旨在根据 了解左心室（LV）力学的变化，材料 急性心肌梗塞（AMI）的特性和几何形状 不同的特定心室位置。 该项目测试一个中央 假设：手术干预措施可以有利地改变心室 重塑或AMI后重塑的影响。 该项目的重点 缺血性二尖瓣反流（MR），前圆锥形动脉瘤和大型 前APICAL AMI。 拟议的工作将利用我们发达的绵羊模型 LV质量的22％和30％的基质心肌梗死； 22％ 产生缺血MR的梗塞涉及前或 后乳头肌； 30％梗塞后，急性，严重的MR；和 不产生动脉瘤或MR的后梗塞。 LV将是 使用四种技术成像； Sonomictry阵列定位（SAL）， 定量超声心动图，串行心室和电影磁 共振成像。 梗塞，边界区和 远程心肌将使用我们的双轴压力扩张进行评估 设备。 二尖瓣亚基相互关系的变化（即环， 乳头状肌肉，邻近的心室壁）冠状动脉后 闭塞会产生缺血的MR；气门本身的组件不 更改（例如，传单，弦乐）。 我们将使用SAL跟踪这些更改 并设计赔偿操作以扭转变化并恢复二尖瓣 瓣膜能力。 我们将使用多种成像技术，双轴应力扩张研究， 和不同的梗塞模型来描述重塑过程 特定尺寸和位置的LV梗死。 我们的目标是定量 区域菌株，计算区域应力，并观察这些 在重塑期间重新分布。 我们将评估LV力学并将其与血液动力学相关 折叠或修补前液体LV动脉瘤后的测量。 我们 将评估一个惰性，感觉贴片和一块可行的斑点 未刺激的骨骼肌。 我们将尝试修改前Apical LV的材料特性 梗塞以减少心室变形并改善心室 通过修改梗塞的材料特性的性能 再灌注，血管紧张素转化酶抑制剂，并通过直接 注入僵硬的材料。 心脏是泵。 这些研究旨在发展手术 干预措施以改善早期和长期心室性能 ami。