Houson Hailey, Hedrick Andria, Awasthi Vibhudutta
Research Imaging Facility Department of Pharmaceutical Sciences College of Pharmacy University of Oklahoma Health Science Center Oklahoma City OK USA.
Hexakit, Inc. Edmond OK USA.
Animal Model Exp Med. 2020 Oct 10;3(4):295-303. doi: 10.1002/ame2.12136. eCollection 2020 Dec.
Drug-induced cardiomyopathy is a significant medical problem. Clinical diagnosis of myocardial injury is based on initial electrocardiogram, levels of circulating biomarkers, and perfusion imaging with single photon emission computed tomography (SPECT). Positron emission tomography (PET) is an alternative imaging modality that provides better resolution and sensitivity than SPECT, improves diagnostic accuracy, and allows therapeutic monitoring. The objective of this study was to assess the detection of drug-induced cardiomyopathy by PET using 2-deoxy-2-[F]fluoro-D-glucose (FDG) and compare it with the conventional SPECT technique with [Tc]-Sestamibi (MIBI).
Cardiomyopathy was induced in Sprague Dawley rats using high-dose isoproterenol. Nuclear [F]FDG/PET and [Tc]MIBI/SPECT were performed before and after isoproterenol administration. [F]FDG (0.1 mCi, 200-400 µL) and [Tc]MIBI (2 mCi, 200-600 µL) were administered via the tail vein and imaging was performed 1 hour postinjection. Isoproterenol-induced injury was confirmed by the plasma level of cardiac troponin and triphenyltetrazolium chloride (TTC) staining.
Isoproterenol administration resulted in an increase in circulating cardiac troponin I and showed histologic damage in the myocardium. Visually, preisoproterenol and postisoproterenol images showed alterations in cardiac accumulation of [F]FDG, but not of [Tc]MIBI. Image analysis revealed that myocardial uptake of [F]FDG reduced by 60% after isoproterenol treatment, whereas that of [Tc]MIBI decreased by 45%.
We conclude that [F]FDG is a more sensitive radiotracer than [Tc]MIBI for imaging of drug-induced cardiomyopathy. We theorize that isoproterenol-induced cardiomyopathy impacts cellular metabolism more than perfusion, which results in more substantial changes in [F]FDG uptake than in [Tc]MIBI accumulation in cardiac tissue.
药物性心肌病是一个重大的医学问题。心肌损伤的临床诊断基于初始心电图、循环生物标志物水平以及单光子发射计算机断层扫描（SPECT）灌注成像。正电子发射断层扫描（PET）是一种替代成像方式，它比SPECT具有更高的分辨率和灵敏度，可提高诊断准确性，并能进行治疗监测。本研究的目的是评估使用2-脱氧-2-[F]氟-D-葡萄糖（FDG）的PET对药物性心肌病的检测，并将其与使用[Tc]-司他米比（MIBI）的传统SPECT技术进行比较。
使用高剂量异丙肾上腺素在Sprague Dawley大鼠中诱导心肌病。在给予异丙肾上腺素之前和之后进行核素[F]FDG/PET和[Tc]MIBI/SPECT检查。通过尾静脉注射[F]FDG（0.1 mCi，200 - 400 μL）和[Tc]MIBI（2 mCi，200 - 600 μL），并在注射后1小时进行成像。通过心肌肌钙蛋白的血浆水平和氯化三苯基四氮唑（TTC）染色确认异丙肾上腺素诱导的损伤。
给予异丙肾上腺素导致循环心肌肌钙蛋白I增加，并显示心肌组织学损伤。在视觉上，给予异丙肾上腺素之前和之后的图像显示[F]FDG在心脏的蓄积有变化，但[Tc]MIBI没有。图像分析显示，异丙肾上腺素治疗后心肌对[F]FDG的摄取减少了60%，而[Tc]MIBI减少了45%。
我们得出结论，对于药物性心肌病的成像，[F]FDG是比[Tc]MIBI更敏感的放射性示踪剂。我们推测，异丙肾上腺素诱导的心肌病对细胞代谢的影响大于灌注，这导致心脏组织中[F]FDG摄取的变化比[Tc]MIBI蓄积的变化更大。
