The computed tomography myocardial perfusing (CTP) is able to detect myocardial ischemia (1,2), increasing diagnostic value of CT angiography in coronary artery disease (3,4). But whether CTP has the ability to give the quantitative assessment of ischemic severity remains uncertain. Therefore, we sought to evaluate the accuracy of CTP for the quantitative assessment of myocardial microvascular function in acute myocardial infarction (AMI), compared with the parameters at CMR perfusion.

11 AMI (post-MI 1 day) Bama mini-pigs underwent single-phase CTP and first-pass CMR perfusion for perfusing parameters (Figure 1). The ROI-based measurements were conducted in infarcted and non-infarcted myocardium for CT and MR parameters (Figure 2,3); and these parameters were then compared by t-test to evaluate myocardial ischemia severity. The agreement between CT and MR parameters was tested using linear regression.

Compared with non-infarcted myocardium, the CT-based MBF and MRI-based max signal intensity (MaxSI) in infarcted myocardium was lower (MBFinfarct= 49.16 ± 12.85 versus BMFnon-infarct= 80.99 ± 8.39, P < 0.001; MaxSIinfarct = 7.93 ± 1.68 versus MaxSInon-infarct = 14.40 ± 4.95, P= 0.04); while the MRI-based time to maximum signal intensity (TTM) in infarcted myocardium is longer (TTMinfarct = 44.92 ± 10.32 versus TTMnon-infarct = 27. 40 ± 11.44, P =0.004). The MBF was positively correlated with MaxSI (r = 0.467, P = 0.012) and...

Acting as a new measurement for myocardial characterization, CTP gives a quantitative assessment of myocardial microvascular function in AMI.

1. Tanabe Y, Kido T, Uetani T, et al. Differentiation of myocardial ischemia and infarction assessed by dynamic computed tomography perfusion imaging and comparison with cardiac magnetic resonance and single-photon emission computed tomography. Eur Radiol. 2016;26(11):3790-3801. 2. Goto Y, Kitagawa K, Uno M, et al. Diagnostic Accuracy of Endocardial-to-Epicardial Myocardial Blood Flow Ratio for the Detection of Significant Coronary Artery Disease With Dynamic Myocardial Perfusion Dual-Source Computed Tomography. Circ J. 2017;81(10):1477-1483. 3. Sørgaard MH, Linde JJ, Kühl JT, et al. Value of Myocardial Perfusion Assessment...