Abstract 19035: Distribution of Macrophages and Vasa Vasorums in Atherosclerotic Plaques in the Left Anterior Descending Coronary Arteries Investigated with Optical Coherence Tomography Color-Coded mapping
Background: It has been reported that the number of cholesterol clefts in the necrotic core, vasa vasorums, and macrophages are significantly greater in ruptured plaques than eroded plaques, or stenotic stable lesions. However, distributional features of each of these factors have not been elucidated well enough.
Methods: Fifty-eight atherosclerotic lesions in 12 left anterior descending coronary arteries of 12 patients with stable angina were visualized by optical coherence tomography (M2 OCT, Light Lab). Plaque components were analyzed by 10 degree intervals in every 0.225mm slice of OCT pictures and classified into fibrosis, lipid, calcification or thrombus. The thickness of fibrosis, fibrous cap and calcification were measured. The results are reflected in the color-coded maps. Also the distribution of plaque rupture, cholesterol clefts, vasa vasorums and clusters of macrophages were investigated by 10 degree intervals in the OCT pictures, and then the results were transferred to the color-coded maps.
Results: The spread of thin fibrous caps (<65 micrometers) were negatively correlated with the distance from the septal branch (proximal side: p=0.047, r=−0.30, distal side: p<0.001, r=−0.64). Ninety-two percent of the macrophages were seen between 1mm distal and proximal from the lipid pools (2044 ROIs/2230 ROIs). A greater number of macrophages were seen around the ruptured plaques (The average numbers of the macrophages around the ruptured plaques and the non-ruptured plaques were 108.7 ROIs and 21.7 ROIs respectively.). Vasa vasorums ran beside the large lipid cores (100%: 104 ROIs/104 ROIs).
Conclusions: This is the first clinical demonstration of the special distribution of each factor of plaque vulnerability by color-coded maps. The color-coded map of OCT is a promising method for the evaluation of tissue characterization of coronary plaques and provides us with a new insight into the spread of atherosclerotic lesions in coronary arteries.
- © 2010 by American Heart Association, Inc.