Schaefer S
Veterans Administration Medical Center, San Francisco, California 94143.
Am J Cardiol. 1990 Oct 26;66(14):45F-50F. doi: 10.1016/0002-9149(90)90642-e.
Nuclear magnetic resonance (NMR) spectroscopy can nondestructively evaluate changes in metabolites with different disease states, as well as with therapeutic interventions. Animal studies have provided the basis for understanding changes in high-energy phosphates with myocardial ischemia. Studies of graded ischemia due to partial coronary stenosis have shown the sensitivity of the ratio of phosphocreatinine to inorganic phosphate to small reductions in myocardial blood flow and its relation to myocardial function. The application of NMR spectroscopy to humans requires precise localization techniques to avoid acquiring contaminating information from structures around the heart, such as the chest wall and diaphragm. With these localization techniques, metabolic evidence of ischemia has been demonstrated in patients with myocardial infarction and patients with known coronary disease, although the sensitivity of this technique for the diagnosis of inducible ischemia is unknown. At rest, patients with dilated and hypertrophic cardiomyopathies often have an elevated phosphodiester resonance, possibly signifying abnormal breakdown of membrane phospholipids. Increasing oxygen demand in these patients does not usually alter high-energy phosphates, suggesting that oxidative energy metabolism is preserved under these conditions. NMR spectroscopy is a powerful tool to increase understanding of metabolic changes in a variety of pathologic conditions.
核磁共振（NMR）光谱法能够无损评估不同疾病状态以及治疗干预下代谢物的变化。动物研究为理解心肌缺血时高能磷酸盐的变化提供了依据。对部分冠状动脉狭窄导致的分级缺血的研究表明，磷酸肌酸与无机磷酸盐的比值对心肌血流量的小幅减少很敏感，且与心肌功能有关。将NMR光谱法应用于人体需要精确的定位技术，以避免获取来自心脏周围结构（如胸壁和横膈膜）的污染信息。借助这些定位技术，已在心肌梗死患者和已知冠心病患者中证实了缺血的代谢证据，尽管该技术对诱导性缺血诊断的敏感性尚不清楚。在静息状态下，扩张型和肥厚型心肌病患者的磷酸二酯共振通常会升高，这可能表明膜磷脂的分解异常。这些患者增加的需氧量通常不会改变高能磷酸盐，这表明在这些情况下氧化能量代谢得以保留。NMR光谱法是增进对各种病理状况下代谢变化理解的有力工具。
