BACKGROUND: Increasing evidence suggests that erythrocytes may participate in atherogenesis. We sought to investigate the relationship between total cholesterol content in erythrocyte membranes (CEM) and coronary atheroma burden in patients with coronary artery disease (CAD).METHODS: We prospectively enrolled 28 participants: 11 patients with angiographically significant CAD and 17 controls. Intravascular ultrasound (IVUS) and 3-dimensional reconstruction of coronary arteries was performed in the patient subgroup.RESULTS: Cholesterol content of erythrocyte membranes was higher in patients compared to controls (P < .01). Cholesterol content of erythrocyte membranes correlated with total atheroma volume (r = .82, P < .01) and with percentage plaque area at the vessel site with minimal lumen area (r = .75, P < .05). On multivariate analysis, CEM was the only variable independently predicting total atheroma volume (P = .05).CONCLUSIONS: This pilot study is the first to demonstrate a significant relation between CEM and coronary atherosclerotic burden, suggesting a possible role of erythrocyte membrane-derived lipids in the expansion of atheromata. The results merit validation in larger studies.