Exogenous radiolabeled annexin A5 is taken up by atherosclerotic tissue. We measured endogenous plasma annexin A5 and circulating oxidized low-density lipoprotein (oxLDL), a biochemical marker of atherosclerosis, in men with either severe angiographically determined coronary stenosis (n = 90) or no or only minor stenosis (n = 96). Men without history of cardiac disease or treatment and free of plaques in the carotid artery (by ultrasonography) were taken as controls (it = 87). Opposite to oxLDL, annexin A5 decreased at increasing severity of stenosis. OxLDL was lowest and annexin A5 was highest in controls. Percentage differences between groups were higher for annexin A5 than for oxLDL, and highest for oxLDL/annexin A5 ratio. The oxLDL/annexin A5 ratio is a better marker of the severity of coronary stenosis than oxLDL alone, may reflect the presence and extent of the atherosclerotic cardiovascular disease, and might prove useful for preclinical screening purposes. (c) 2007 Elsevier Inc. All rights reserved.