Low shear stress and flow reversal characterize areas of predilection for atherosclerotic lesions within the vasculature. In this study, we applied a complex flow pattern to endothelial cells that was characterized by particle velocity determination using laser. Endothelial cells exposed to low shear stress and flow reversal demonstrated higher levels of monocyte binding compared with endothelial cells exposed to steady one-directional flow. These finds suggest a mechanism by which areas of low shear stress and flow reversal are predisposed to the development of atherosclerotic lesions. In addition endothelial cells exposed to low shear stress and flow reversal were able to respond to inflammatory stimuli such as TNF- or lipopolysaccharide with substantial further increases in monocyte binding.