Case 3 is categorized to CAD-RADS 5 because of total occlusion.
Case 290
【Progress】
All cases received invasive angiography. Case 3 underwent coronary intervention using metallic stent.
【Discussion】
P score is based on amounts of plaques with calcification or non-calcification in number of segments which are numbered from #1 to #16; P1; plaques in 2 segments or less; P2 plaques in 3 or 4 segments; P3; plaques in 5 – 7 segments: P4 plaques in eight or greater segments. High risk plaques indicate positive remodeling (necrosis or lipid accumulation is greater 1.5 times greater than vascular wall thickness)(2, 3), low attenuation plaque (CT value of plaque less than 30), napkin-ring sign (relatively low attenuation from thickened wall itself protruded into lumen) (1, 4). High risk plaques imply non-calcified plaque rather than calcified plaque.
Clinical practice to make report for coronary artery disease includes; first step is to find and calculate plaques irrespective of calcified or non-calcified in each main three vessels and left main trunk and then, identify the number of segment where plaques exist, indicating to be able to make P score; second step is to find out which plaque causes the most stenosis and then, identify its most stenotic ratio, clarifying to be corresponded to minimum stenosis (1 - 24%), mild stenosis (25 – 49%), moderate stenosis (50 – 69%), severe stenosis (70 – 99%) or extensive stenosis (100%): third step is to check presence or absence of high risk plaque that indicates above and then, to check presence or absence of plaque in left main trunk. This process leads to make report according to CAD-RADS (coronary artery disease-reporting and data system) version 2 (1, 4).
It is imperative to identify coronary artery disorder of CADS-RADS 4a, 4b or 5 which is needed the further invasive catheter examination and management. Meanwhile, coronary artery disorder with CADS-RADS 3 is required to ischemic cardiac test such as SPECT scintigram or CT-FFR (1).
It might not be reasonable to calculate the number of plaques because calcified plaques sometimes extend in succession and the edge of non-calcified plaque is unclear. However, it is useful to grasp the whole situation of coronary artery disorder including to notify the presence of high-risk plaque. Then, it is easy and certain to calculate the number of segments with plaques.
In Case 1, severe stenosis of 70 – 99% was found in two vessels of left anterior descending (LAD) and left circumflex (LCX), indicating CADS-RADS 4a. In Case 2, severe stenosis of 70 – 99% is found in one vessel of LAD, indicating CADS-RADS 4a. In Case 3, total occlusion of right coronary artery, severe stenosis of 70 – 99% in two vessels of LAD and LCX were found, indicating CADS-RADS 5. In Case 4, moderate stenosis of left main trunk and severe stenosis of 70 – 99% in two vessels of right coronary artery and LAD, indicative of CADS-RADS 4b.
【Summary】
We presented 4 cases with coronary artery occlusive diseases; CAD-RADS 4a in two cases, CAD-RADS 4b in one case and CAD-RADS 5 in one case. All cases were scheduled to examine invasive catheter angiography for presence or absence of ischemia by measuring pressure gradient. It is borne in mind that P score is based on number of segments with plaques irrespective of calcified or non-calcified. It is imperative to make P score not only to notify the presence of plaque but to realize the high-risk plaque, indicating that remodeling (necrosis or lipid accumulation is greater 1.5 times greater than vascular wall thickness), low attenuation plaque (CT value of plaque less than 30), napkin-ring sign (relatively low attenuation from thickened wall itself protruded into lumen). Further, CAD-RADS 4a or greater indicates necessity of assessment of ischemia including invasive cardiac angiography and coronary intervention.
【References】
1.Cury, R. C., et al. CAD-RADS™ 2.0 - 2022 Coronary Artery Disease-Reporting and Data System: An Expert Consensus Document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Cardiology (ACC), the American College of Radiology (ACR), and the North America Society of Cardiovascular Imaging (NASCI). J Am Coll Radiol Available online 8 July 2022
2.Nelson Camacho N, et al. Infrarenal Abdominal Penetrating Aortic Ulcer, an Atypical Location of a Rare Disease. Rev Port Cir Cardiotorac Vasc. 2017;24(3-4):176.
3.Sato M et al. Abdominal aortic disease caused by penetrating atherosclerotic ulcers. Ann Vasc Dis. 2012;5(1):8-14
4.Cury, R. C., et al. (2016). “CAD-RADS: Coronary Artery Disease – Reporting and Data System.: An Expert Consensus Document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (NASCI). Endorsed by the American College of Cardiology.” J Am Coll Radiol 13(2 Pt A): 1458 – 1466.
2023.2.10