Tamaki N, Kawamoto M
Department of Nuclear Medicine, Kyoto University Faculty of Medicine, Japan.
J Nucl Cardiol. 1994 Mar-Apr;1(2 Pt 2):S72-8. doi: 10.1007/BF02940072.
Free fatty acid is a major substrate fuel for normal myocardium. Cardiovascular disease is frequently associated with impairment of fatty acid oxidation. Therefore assessment of fatty acid metabolism may be an important tool for the early detection of myocardial abnormalities and may provide insight into pathologic heart conditions. Although carbon 11-labeled palmitate is a well-established tracer for probing myocardial fatty acid metabolism, a variety of iodinated fatty acid compounds have been introduced for assessing fatty acid metabolism, including straight-chain and branched-chain fatty acid compounds. Straight-chain fatty acid has advantages for measuring fatty acid oxidation on the basis of tracer clearance from the myocardium. Branched-chain fatty acid can be trapped in the myocardium without further washout and uptake in the myocardium may reflect fatty acid retention and some aspect of fatty acid metabolism. A long tracer retention period makes feasible the acquisition of single-photon emission computed tomographic images. This review examines the characteristics of both types of tracers and our recent clinical experience with beta-methyliodophenyl pentadecanoic acid, which has potential for detecting and characterizing both ischemic heart disease and cardiomyopathy.
游离脂肪酸是正常心肌的主要底物燃料。心血管疾病常与脂肪酸氧化受损相关。因此，评估脂肪酸代谢可能是早期检测心肌异常的重要工具，且可能为了解病理性心脏状况提供线索。尽管碳-11标记的棕榈酸是用于探究心肌脂肪酸代谢的成熟示踪剂，但已引入多种碘化脂肪酸化合物来评估脂肪酸代谢，包括直链和支链脂肪酸化合物。直链脂肪酸在基于示踪剂从心肌清除的情况来测量脂肪酸氧化方面具有优势。支链脂肪酸可滞留在心肌中而不会进一步洗脱，心肌摄取情况可能反映脂肪酸滞留及脂肪酸代谢的某些方面。较长的示踪剂滞留期使得获取单光子发射计算机断层扫描图像成为可能。本综述探讨了这两种示踪剂的特性以及我们近期使用β-甲基碘化苯基十五烷酸的临床经验，该示踪剂在检测和表征缺血性心脏病及心肌病方面具有潜力。
