Evaluate Rat Myocardial Ischemia Model by Micro-PET with Two Tracers

The myocardial ischemia model by LAD ligature was established and evaluate it with 3 methods. The traditional method is T wave changes in ECG. The classic method is TTC staining. The new method is ¹³NH₃•H₂O and ¹⁸F-FDG Micro-PET imaging. Using ECG, 9 of 12 rats were judged as successful models. Using Micro-PET, only 6 of 9 rats were judged as successful models, which was consistent with TTC staining results. Micro-PET imaging indicated that before the model was established, the ¹³NH₃•H₂O and ¹⁸F-FDG were well-distributed in the myocardial of rats, the standardized uptake value (SUV) of ¹³NH₃•H₂O and ¹⁸F-FDG of myocardial ischemia were 3.78±0.59（n=12）and 2.30±0.21(n=12). After the model was established, only 6 rats shows abnormal myocardial perfusion and metabolism, the SUV of ¹³NH₃•H₂O and ¹⁸F-FDG of myocardial ischemia model were 2.78±0.46（n=6） and 1.65±0.21（n=6）. The result showed taht the accuracy rate of Micro-PET method was 100%, while the traditional method is 66.67%. In conclusion, ¹³NH₃•H₂O and ¹⁸F-FDG Micro-PET image maybe more precise and objective than ECG.