Clinical Course of Optical Coherence Tomography-Detected Lipid-Rich Coronary Plaque After Optimal Medical Therapy

Abstract

Background:The aim of this study was to evaluate optical coherence tomography (OCT)-detected lipid-rich coronary plaques (LRCPs) with coronary computed tomography angiography (CCTA) 10 months after optimal medical therapy (OMT). Methods and Results:Baseline OCT detected 28 LRCPs in non-culprit lesions. High-risk plaque features (HRPFs), such as positive remodeling, very low attenuation plaques, napkin-ring sign, and spotty calcification, were observed in 67.9%, 67.9%, 21.4%, and 64.3% of LRCPs, respectively, at the 10-month follow-up CCTA. Lesions with ≥3 HRPFs were defined as high-risk LRCPs (n=12); the remaining were defined as low-risk LRCPs (n=16). The maximum lipid arc on baseline OCT was larger in high-than low-risk LRCPs (221±62° vs. 179±44°, respectively; P=0.04). Receiver operating characteristic curve analysis indicated that a maximum lipid arc >154° on baseline OCT was the optimal cut-off value to predict high-risk LRCPs 10 months after OMT. Patients with high-risk LRCPs had worse clinical outcomes, defined as a composite of cardiac death, target lesion-related myocardial infarction, and target lesion-related revascularization, during follow-up than those with low-risk LRCPs (33.3% vs. 0%; P=0.01). Conclusions:A high-risk LRCP at follow-up CCTA was correlated with a larger maximum lipid arc on baseline OCT. Further aggressive treatment for patients with large LRCPs may reduce vulnerable plaque features and prevent future cardiac events.

Prediction of optical coherence tomography-detected calcified nodules using coronary computed tomography angiography

“…CCTA-measured CACS is widely used for the quantitative evaluation of calcium burden [9] and prediction of coronary events [10,11], and is calculated based on regions with CT values ≥ 130 HU [9]. On the other hand, CPV is calculated by the total volume of regions with CT values > 500 HU, which was de ned as the threshold to detect calci ed plaques based on the results of previous studies with intravascular imaging [6][7][8].…”

“…Retrospective CCTA studies were performed for each vessel evaluated with OCT. Coronary plaques were de ned as structures with a minimum 1 mm² area within or adjacent to the arterial lumen, clearly distinguishable from the vessel lumen, and surrounded by pericardial tissue; tissue with signal intensity below − 30 Houns eld units (HU) was considered pericardial fat and excluded from the analysis. Based on the results of our previous study with OCT [7][8][9], each tissue was classi ed by its CT value (< -30, -30 to 50, 51 to 200, 201 to 500, and > 500 HU indicated pericardial fat, low-attenuation plaque, brous plaque, enhanced media, and calci ed plaque, respectively). Non-calci ed plaques were de ned as lowattenuation or brous plaques.…”

“…Coronary computed tomography angiography (CCTA) is a noninvasive tool for evaluating the coronary plaque morphology; coronary plaques can be classi ed on the basis of computed tomography (CT) values as low-attenuation, brous, and calci ed plaques, with quantitative assessment of plaque volumes [6][7][8]. CCTA-calculated coronary artery calcium score (CACS) is widely used to quantitatively evaluate the coronary artery calcium burden [9], where a higher CACS is related to poorer clinical outcomes as compared with lower CACS [10,11].…”

Prediction of optical coherence tomography-detected calcified nodules using coronary computed tomography angiography

“…In addition, we evaluated the lesion length (mm), minimal lumen diameter (mm), % diameter stenosis, minimal lumen area (mm 2 ), and % area stenosis. % diameter stenosis and % area stenosis are calculated as mean reference lumen diameter minus the minimal lumen diameter divided by the mean reference lumen diameter and mean reference lumen area minus the minimal lumen area divided by the mean reference lumen area in the cross-sectional images, respectively 9 . Mean reference diameter and mean reference area are defined as (proximal + distal reference diameters) divided by 2 and (proximal + distal reference areas) divided by 2, respectively.…”

“…Coronary computed tomography angiography (CCTA) is a non-invasive tool for evaluating the coronary plaque morphology; coronary plaques can be classified on the basis of computed tomography (CT) values as low-attenuation, fibrous, and calcified plaques, with quantitative assessment of plaque volumes 6 – 8 . CCTA-calculated coronary artery calcium score (CACS) is widely used to quantitatively evaluate the coronary artery calcium burden 9 , where a higher CACS is related to poorer clinical outcomes as compared with lower CACS 10 , 11 .…”