Correlation of 99 Tcm-MIBI gated myocardial perfusion SPECT imaging and two-dimensional speckle tracking imaging in swine model of myocardial infarction / 中华核医学与分子影像杂志

ABSTRACT

Objective To evaluate the value of speckle tracking imaging( STI) by investigating the correlation and consistency between two?dimensional STI and 99 Tcm?MIBI G?MPI in the assessment of myo?cardial injury and myocardial infarction ( MI) of swine model. Methods Eight healthy and same?age adult female Tibetan swine were used to establish animal models of MI induced by open?chest ligation of the first diagonal branch of the left anterior descending coronary artery. The swine underwent ultrasonic cardiogram and G?MPI before and at 6, 24, 48, 72 and 96 h after the operation. The myocardial perfusion was evalua?ted. Ultrasonic sectional graphs were collected to analyze ultrasonic short?axis horizontal peak values of sys?tolic radial strain ( SR) and systolic circumferential strain ( SC) and local myocardial rotation angle ( Rot) of different segments of the left ventricle with off?line STI. Left ventricular ( LV) EDV, LVESV, LVEF by G?MPI and ultrasonography were compared. Pearson correlation analysis and repeated measures analysis of variance were used. Results Six models were successfully constructed. Six hours after the coronary artery ligation, the G?MPI showed no significant or very few perfusion defects;24, 48, 72 and 96 h after the liga?tion, G?MPI showed sparseness and defects at the anterior septum, anterior and lateral wall of apical seg?ment of apical segment. The peak strain values of SR, SC and Rot at the anterior septal apical segment, the anterior and lateral wall of apical segment decreased at different time points after the ligation. Six hours after the coronary artery ligation, the STI was positive. For healthy swine, the LVEF measured with G?MPI and ultrasonic STI showed good correlation ((68±3)% vs (70±4)%, r=0.84, P<0.05). The LVEF values of G?MPI and ultrasonic STI at 6, 24, 48, 72, 96 h after the ligation were (79±1)%, (80±4)%, (58±2)%, (54±4)%, (57±4)%, and(76±2)%,(76±3)%,(57±3)%,(55±3)%,(68±6)% (r0.40-0?76, all P<0.05). LVEDV and LVESV measured by the two methods showed variation trends at different time points ( F=64.104, 30?069, 35.186, 54.903, all P<0.01) with good consistency after the ligation. Conclusions Ultrasonic STI could estimate the myocardial injury at an earlier stage and measure the severity of damaged myocardium quantitatively, and the resluts are in good agreement with myocardial perfusion and function by G?MPI.