Measurement of the Uniaxial Mechanical Properties of the Healthy and Atherosclerotic Human Coronary Arteries

Atherosclerosis is a common cardiovascular disease causes many deaths worldwide. In this study، we tried to measure the uniaxial mechanical properties of healthy and atherosclerotic human coronary arteries using a tensile test machine. These are including، maximum stress and strain as well as physiological and maximum elastic modulus. In this study stress and strain are defined as the ratio of predefined force per area of sample، and the variation of sample’s length per its initial length. In addition، elastic modulus is defined as the ratio of stress per strain in the linear part of obtained stress-strain diagram. Furthermore، the force-displacement diagram of human coronary artery is obtained to discern the alterations between the healthy and atherosclerotic arterial wall stiffness. In this study، 22 coronary arteries were excised from human cadavers during autopsy، including 14 healthy and 8 atherosclerotic arteries. The obtained arteries were carried out on a uniaxial tensile test machine and load was applied until breakage occured. Finally، the force-displacement of each artery was obtained and plotted separately The results show that the atherosclerotic arteries bear 44. 55% more stress and 34. 61% less strain compared to the healthy ones. The physiological and maximum elastic moduli of healthy arteries are 2. 53 and 2. 91 times higher than that of atherosclerotic arteries، respectively. It is believed that the formed plaque in a coronary artery during atherosclerosis brings about the obtained stiffness. This could have substantial asset in the elastic behavior of artery during blood supply and can affect its performance. These results could be utilized to understand the extension and rupture mechanism of coronary arteries and has implications for interventions and surgeries، including balloon-angioplasty، bypass، and stenting.