RESPONSES TO REGIONAL MYOCARDIAL ISCHEMIA BY 31P NMR

31P NMR 对局部心肌缺血的反应

• 批准号: 3347353
• 负责人: HOWARD L KANTOR
• 金额: $ 16.36万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-12-01 至 1988-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3347353
• 关键词: cardiovascular disorder prevention; diagnosis quality /standard; electrodes; heart catheterization; heart circulation; heart disorder diagnosis; heart function; heart imaging /visualization /scanning; heart metabolism; heart revascularization; myocardial infarct sizing; myocardial infarction; myocardial ischemia /hypoxia; myocardium; particle; radiotracer; stable isotope diagnosis; thermal blood flow measurement

The proposed study will examine the metabolic response of the myocardium under the stress of ischemia. Metabolites will be measured by 31P NMR spectroscopy permitting measurement without the need for biopsy. This will enable repeated measurements over time in response to graded stimuli, and a careful observation of recovery. In vivo intact canine hearts will be examined via two NMR detection methods. The first will use the catheter-coil technique in which a coil is advanced through a peripheral blood vessel to the heart. Refinement of this technique represents one of the project aims, permitting spectra from localized myocardial regions to be collected without the need for major surgery and in times which are practical for the examination of the stressed myocardium. The second method involves the placement of epicardial surface coils at the time of thoracotomy. The combination of these two methods permits selective observation of signal from tissue at various depths from the subendocardium to the subepicardium. Spectra will be collected from myocardial regions subjected to graded ischemia using a balloon occluder placed on a proximal coronary segment, and the myocardium will be further stressed by rapid pacing. Adjacent areas will also be investigated and results correlated with tissue perfusion as measured by the microsphere technique. Additionally, function will be determined by radionuclide ventriculography to assess wall motion in the observed area. The overall objective of this proposal is to study cardiac ischemia and its transient and persistent effects on myocardial function. This information is intended to assist in the diagnosis and management of ischemia, and may enable others to develop new treatment regimens to either prevent or limit myocardial infarction.

拟议的研究将检查心肌的代谢反应 在缺血的压力下。 代谢物将通过31p NMR测量 光谱允许测量无需活检。 这会 随着时间的推移，启用重复测量，以响应分级刺激和A 仔细观察恢复。 体内完整的犬心将通过两个NMR检测检查 方法。 第一个将使用线圈的导管线圈技术 通过外周血血管前进到心脏。 改进 该技术代表了该项目的目标之一，允许光谱 局部的心肌区域，无需重大 手术和在检查的时间 压力心肌。 第二种方法涉及放置 胸切开术时心外膜表面线圈。 结合 这两种方法允许选择性观察来自组织的信号 从心内膜下到心肌下的各种深度。 光谱将从经过分级的心肌区域收集 使用放置在近端冠状动脉片段上的气球封闭器的缺血， 快速起搏将进一步强调心肌。 邻近的 还将研究区域，结果与组织相关 通过微球技术测量的灌注。 另外，功能 将通过放射性核素室里确定以评估壁运动 在观察到的区域。 该提议的总体目的是研究心脏缺血及其 瞬态和持续对心肌功能的影响。 此信息 旨在协助缺血的诊断和管理，可能 使其他人制定新的治疗方案以预防或限制 心肌梗塞。