Serial Change of Perivascular Fat Attenuation Index in a Case of Spontaneous Coronary Artery Dissection Involving the Proximal Left Coronary Artery

Figure 1.. (A) Three-dimensional volume-rendered reconstruction image of initial cardiac computed tomography (CCT) performed the day before hospital admission showing mild stenosis in the left main truncus (LMT), severe stenosis in the proximal left anterior descending coronary artery (LAD, yellow arrow) and mild stenosis in the proximal to mid-left circumflex coronary artery (LCX). (B) Initial coronary angiography (CAG) of the left coronary artery (LCA, right anterior oblique 40° caudal 25° projection) performed 1 day after initial CCT (hospital day 1) showing total occlusion in the mid-portion of the LCX (white arrows), mild stenosis in the LMT to proximal LCX, and mild to moderate stenosis in the proximal LAD. (C) Intravascular ultrasound (IVUS) throughout the LMT, LAD, and LCX in initial CAG showing a large intramural hematoma (IMH) compressing the true lumen along the LMT to proximal LAD and the entire LCX. In particular, the IMH severely compressed the true lumen in the mid-portion of the LCX. Arrowheads indicate the position of the cross-sectional IVUS images in the corresponding site of the LCA in B. (D) Three-dimensional volume-rendered reconstruction image of the second CCT scan…

Figure 2.. Changes in the cardiac computed tomography (CCT) findings of the left anterior descending coronary artery (LAD). (A-C) Curved multiplanar reconstruction (A), straightened multiplanar reconstruction (B, left), and cross-sectional (B, right) images of the LAD at the initial CCT performed the day before hospital admission showing mild stenosis in the left main trunk (LMT), followed by severe stenosis in the proximal LAD (yellow arrow) with a low-to-intermediate density structure (20-80 HU). Perivascular fat attenuation index (FAI) values of the LMT and LAD were -60.7 HU and -64.3 HU (C). (D-F) Curved multiplanar reconstruction (D), straightened multiplanar reconstruction (E, left), and cross-sectional (E, right) images of the LAD at the second CCT performed 8 days after the initial CCT (hospital day 8), showing mild stenosis in the LMT and mild to moderate stenosis in the proximal LAD (blue arrow). Perivascular FAI values of the LMT and LAD were -69.6 HU and -75.8 HU (F). (G-I) Curved multiplanar reconstruction (G), straightened multiplanar reconstruction (H, left), and cross-sectional (H, right) images of the LAD at the third CCT scan performed 1,164 days after the initial CCT scan…

Figure 3.. Changes in cardiac computed tomography (CCT) findings of the left circumflex coronary artery (LCX). (A-C) Curved multiplanar reconstruction (A), straightened multiplanar reconstruction (B, left), and cross-sectional (B, right) images of the LCX at initial CCT performed the day before hospital admission showing mild stenosis proximal to mid-LCX with a low-to-intermediate density structure (30 to 100 HU). The perivascular fat attenuation index (FAI) value of the LCX was -66.3 HU (C). (D-F) Curved multiplanar reconstruction (D), straightened multiplanar reconstruction (E, left), and cross-sectional (E, right) images of the LCX at the second CCT performed 8 days after the initial CCT (hospital day 8), showing mild stenosis in the proximal LCX and severe stenosis in the mid-portion of the LCX (red arrow). The perivascular FAI value of the LCX was -65.3 HU (F). (G-I) Curved multiplanar reconstruction (G), straightened multiplanar reconstruction (H, left), and cross-sectional (H, right) images of the LCX at the third CCT performed 1,164 days after the initial CCT (approximately 3 years after hospital discharge) showing no stenosis in the LCX. The perivascular FAI value of the LCX was…