利用小动物SPECT/CT和^(99m)锝-葡糖二酸评估急性缺血坏死心肌动物

In vivo imaging of ^(99m)Tc-Glucarate-labeled acute necrotic myocardium using microSPECT /CT

目的利用99m锝-葡糖二酸(99mTc-Glucarate)和小动物SPECT/CT评估大鼠急性心肌缺血再灌注损伤后缺血坏死心肌的位置和范围。方法建立大鼠急性缺血再灌注损伤模型,手术1 d后尾静脉注射99mTcGlucarate,注射30 min后利用小动物SPECT/CT融合技术分析99m锝-葡糖二酸标记的心肌组织的位置和范围,并与氯化三苯基四氮唑(triphenyltetrazolium chloride,TTC)染色法标记的缺血坏死心肌比较。结果小动物SPECT/CT结果显示手术组心肌坏死部位的99m锝-葡糖二酸的放射性摄取率(心肝比值1.90±0.33)明显高于正常组大鼠(P<0.05),利用小动物SPECT/CT融合技术定位的缺血坏死心肌范围和TTC染色法的测量结果呈线性相关(R2=0.964)。结论通过99m锝-葡糖二酸可以特异性地标记急性缺血坏死心肌,利用小动物SPECT/CT融合技术可以无创性地分析急性缺血坏死心肌的位置和范围。

Objective To evaluate the anatomic localization and size of acute necrotic myocardium in the ischemic-reperfused rat hearts using 99m TC-Glucarate and microSPECT/CT.Methods The ischemic-reperfused （ IR） rat heart models were established by ligating left anterior descending coronary artery for 60 min.99mTC-Glucarate was intravenously injected into the rats 24 hours after IR operations .Images were acquired 30 min after administration of 99m TC-Glucarate using microSPECT/CT. Anatomic localization and size of acute necrotic myocardium were analyzed with microSPECT/CT imaging , and these results were compared to those determined by triphenyltetrazolium chloride （ TTC ） staining.Results The microSPECT/CT images showed hot spot accumulations of 99mTC-Glucarate in IR hearts （the heart-to-liver ratio was 1.90 ±0.33）, not in controls （P 〈0.05）.The anatomic localization of 99mTC-Glucarate-labeled necrotic myocardium were in correspondence with TTC staining results .The hot spot size was related significantly to necrotic myocardial size determined by TTC staining （ R2 =0.964 ） .Conclusions The localization and size of acute necrotic myocardium can be assessed by non-invasive microSPECT/CT imaging with99m Tc-Glucarate.