Integrated imaging evaluation of chronic myocardial ischemia in Chinese mini-swine model

Objective To assess multi-detector CT(MDCT),MR and single photon emission computed tomography(SPECT) in detection of chronic myocardial ischemia in Chinese mini-swine models.Methods Six male pigs received MDCT scan firstly.Then Ameroid narrow ring was placed in the left descending branch and MDCT,MR were performed at the same day.On the 2nd,27th day,SPECT was given.Coronary angiography(CAG) was given on the 28th day,and then MDCT and MRI.The animals were killed after allexaminations.The pathological examination was given at last.Results Two pigs died during the rearing and another 4 had results.Pathology showed 3 had subendocardium infarction and 1 had no infarction.CAG showed infarction in 3 pigs with stenosis more than 50%.Areas of reduced perfusion in arterial phase MSCT,first-pass MRI and SPECT were consistent to findings of TTC staining.MDCT detected that ESV on the 28th day was higher than that of preoperative and postoperative day(P 0.05),the other indexes had no difference.MRI displayed that EDV on the 28th day was higher than that of postoperative day(P 0.001),the other indexes had no differences.SV and EDV measured with MDCT were higher than those with MRI(all P 0.05).ESV and EF measured with MDCT and MRI had no statistical difference(all P 0.05).CT value of left ventricular anterior wall on preoperative,postoperative day and the 28th day were statistically different(F= 10.274,P= 0.011).Conclusion Arterial phase of MDCT,first-pass perfusion of MRI and SPECT all show reducing perfusion in left ventricular anterior wall corresponded to myocardial infarction with TTC staining.CT value of myocardial ischemia decreases after myocardial ischemia.