In order to develop an evaluation method for the endothelial function from blood flow information, a mathematical model and simulation technique that can simultaneously analyze hemodynamics and vessel wall dynamics were proposed. Experimental observations reveal that the proposed method adequately reproduced blood flow data. There was also confirmation that the method enables access of the internal state of the blood vessels, which is difficult to measure directly.

Endothelial dysfunction is known to be the early stage of arteriosclerosis. The flow‐mediated dilation (FMD) test is the most commonly used method to diagnose the endothelial function. The test measures the maximum vasodilation (FMD response) on the brachial artery induced by the increases in blood flow after cuff deflation on the forearm. The vessel diameter must be captured clearly with the ultrasonic probe during the test. The vasodilation is induced in response to changes in the mechanical property of the vessel wall due to the blood flow stimulation. The changes are supposed to affect the pulsatile flow, but the influence of continuous behavior of vascular property on hemodynamics has not been clarified. In this study, in order to clarify the influence of the FMD response on hemodynamics, we propose a mathematical model that can simulate hemodynamics and vasomotor responses. As a result, it was shown that vessel wall dynamics affected the pulsatile flow. This result suggests that the endothelial function can be evaluated from blood flow.

Endothelial dysfunction is known to be the early stage of arteriosclerosis. The flowmediated dilation (FMD) test is the most commonly used method to diagnose the endothelial function. The test measures the maximum vasodilation (FMD response) on the brachial artery induced by the increases in blood flow after cuff deflation on the forearm. The vessel diameter must be captured clearly with the ultrasonic probe during the test. The vasodilation is induced in response to changes in the mechanical property of the vessel wall due to the blood flow stimulation. The changes are supposed to affect the pulsatile flow, but the influence of continuous behavior of vascular property on hemodynamics has not been clarified. In this study, in order to clarify the influence of the FMD response on hemodynamics, we propose a mathematical model that can simulate hemodynamics and vasomotor responses. As a result, it was shown that vessel wall dynamics affected the pulsatile flow. This result suggests that the endothelial function can be evaluated from blood flow. K E Y W O R D S arteriosclerosis, hemodynamics, mathematical model Electron Comm Jpn. 2018;101:19-26.