Schelbert H R
Department of Radiological Sciences, UCLA School of Medicine 90024.
Int J Card Imaging. 1987;2(4):199-208. doi: 10.1007/BF01784776.
Positron emission tomography and tracers of blood flow and of metabolism offer a most unique capability: The noninvasive study of regional myocardial metabolism and its derangements as a result of regional or global myocardial disease. Research with PET not only has confirmed the existence of metabolic fluxes and reactions as established previously through highly invasive or even destructive investigational techniques but has provided new insights into pathophysiologic processes, especially in ischemic and post-ischemic myocardium. From these investigations in both animal experiments and in humans, observations have emerged which indicate a place for PET in clinical cardiology. PET is likely to contribute to detection of disease, to characterizing its extent and severity as well as to decide upon the most appropriate therapeutic strategy and assessing its results. It is recognized that many of these observations with clinical implications await confirmation through larger clinical trials, follow-up studies as well as independent confirmation. Besides exploring ischemic heart disease, PET is equally suitable for examining substrate fluxes and interactions in other disorders as for example in intrinsic myocardial disease like primary and secondary cardiomyopathies. While derangements of metabolism in these disorders may be an expression of the consequences of the disease process or its underlying mechanisms itself, findings on PET will allow formulation of new hypotheses on disease mechanisms that conversely can then be tested. In addition to F-18 2-deoxyglucose and C-11 palmitate, the number of tracers for substrate metabolism is likely to increase. An example is C-11 acetate currently intensely investigated as a tool for measuring overall myocardial oxidative metabolism. Others as for example C-11 labeled short chain fatty acids are on the horizon. The study of cardiac receptors is similarly possible. Thus, a set of tools will soon be available for dissection of entire metabolic pathways and for determination of rate limiting steps in health and disease and to more clearly define specific defects in biochemical reaction steps that critically contribute to or even ae the specific cause of disease.
对局部心肌代谢及其因局部或整体心肌疾病而发生的紊乱进行无创研究。正电子发射断层扫描研究不仅证实了先前通过高度侵入性甚至破坏性研究技术所确立的代谢通量和反应的存在，还为病理生理过程提供了新的见解，尤其是在缺血和缺血后心肌方面。从动物实验和人体的这些研究中，已经出现了一些观察结果，表明正电子发射断层扫描在临床心脏病学中具有一席之地。正电子发射断层扫描可能有助于疾病的检测、确定其范围和严重程度，以及决定最合适的治疗策略并评估其结果。人们认识到，许多这些具有临床意义的观察结果有待通过更大规模的临床试验、随访研究以及独立验证来证实。除了探索缺血性心脏病外，正电子发射断层扫描同样适用于检查其他疾病中的底物通量和相互作用，例如原发性和继发性心肌病等原发性心肌疾病。虽然这些疾病中的代谢紊乱可能是疾病过程后果或其潜在机制本身的一种表现，但正电子发射断层扫描的结果将有助于形成关于疾病机制的新假设，然后可以反过来对这些假设进行检验。除了F-18 2-脱氧葡萄糖和C-11棕榈酸酯外，用于底物代谢的示踪剂数量可能会增加。一个例子是目前正在深入研究的C-11乙酸盐，它作为测量整体心肌氧化代谢的工具。其他的，例如C-11标记的短链脂肪酸也即将出现。对心脏受体的研究同样可行。因此，一套工具很快将可用于剖析整个代谢途径，确定健康和疾病状态下的限速步骤，并更清楚地界定对疾病有重要贡献甚至是疾病特定病因的生化反应步骤中的特定缺陷。
