Theoretical investigation of mass transport to arterial walls in various blood flow regions— II. oxygen transport and its relationship to lipoprotein accumulation

Abstract A theoretical investigation is presented to determine oxygen transport from blood to arterial walls in various blood flow regions and the relationship between oxygen transport and lipoprotein accumulation. The analysis was based on the conservation principles of fluid dynamics and diffusing oxygen molecules for laminar, boundary layer flow at a speed averaged over the cardiac cycle. Increased oxygen transport was predicted in accelerated flow regions, but significantly reduced oxygen transport was indicated in decelerated flow regions and at separation locations on the back side of atheromas, constrictions, and at arterial branches. These trends are opposite to those found for lipoprotein transport and suggest the critical nature of oxygen deprivation and larger lipoprotein accumulation on the back side of atheromas, at constrictions, and at arterial branches. This may manifest itself in more lipid accumulation and atheroma evolution characteristic of atherosclerosis that have been observed under hypoxic conditions. To test this hypothesis between metabolic and filtration concepts requires experimental measurements in vivo in various blood flow regions in arteries to support or substantiate the contention that alterations in oxygen transport and lipoprotein accumulation at selected sites are factors in the pathogenesis and progression of atheromas leading to further vessel narrowing.