Relationships between inflammatory mediators and coronary plaque composition in patients with stable angina investigated by ultrasound radiofrequency data analysis

Inflammation has been recognized as a critical process in the progression of coronary atherosclerosis. Virtual Histology-intravascular ultrasound (VH-IVUS) has been reported to be a useful tool for tissue characterization of coronary atherosclerotic plaque. We investigated relationships between plaque composition and inflammation-related factors possibly contributing to atheromatous plaque formation and progression, since these are largely unknown. Using VH-IVUS, we measured plaque volume and composition at the culprit lesions in patients with stable angina undergoing elective percutaneous coronary intervention (n = 33, 39 de novo lesions), and then analyzed correlations between plaque components and serum levels of inflammatory factors in both aorta and culprit coronary artery obtained by aspiration using a distal protection device. Linear regression analysis revealed that both aortic and coronary LDL cholesterol levels correlated with %plaque burden along the culprit lesions (r = 0.535 and 0.539, respectively), but with none of the plaque components. Of %plaque components, fibro-fatty (FF) correlated positively with both aortic and coronary T cell/B cell ratios (r = 0.335 and 0.359, respectively) whereas necrotic core (NC) correlated negatively with both aortic and coronary T cell/B cell ratios (r = -0.373 and -0.483, respectively). These results suggest that LDL cholesterol may be a good marker for total coronary plaque volume whereas the lymphocyte subset of T cell/B cell ratios may be a good marker for plaque composition, especially FF and NC components volume.