THROMBUS INITIATION WITH SUBSEQUENT GROWTH MEASURED FOR PHYSIOLOGICAL SHEAR AND HIGH PATHOLOGICAL SHEAR

摘要

Arterial thrombosis is often found near an atheroma in atherosclerotic disease, which can lead to acute myocardial infarction, i.e. a heart attack. Thrombus typically grows in regions of exposed subendothelium, which can exist when the plaque cap of the atheroma ruptures or erodes. The subendothelium creates an adherent surface to platelets and other thrombus constituents. Furthermore, an atheroma alters the normal physiological hemodynamics, which has been reported to correspond to local thrombus growth, despite equally adherent surfaces in undisturbed flow regions [1,2]. However, there has been some disagreement about which hemodynamics, specifically shear, may play the most influential role of localizing thrombus. Low shear and high shear have both resulted in thrombus growth [1,2]. Shear in the region of an atheroma can get over 100,000 s~(-1) [3]. Here, we evaluate thrombus growth over a stenosis that replicates the shape of an idealized atheroma. We perfuse whole blood through the stenosis at low flow rates and also at relatively high flow rates. The purpose is to compare low and high shear effects in a single experiment. Thrombus growth is monitored and recorded. An edge-detection technique is then used to evaluate the thrombus boundary, which is then used quantify the local hemodynamics through computational fluid dynamics (CFD).