Effect of high- intensity exercise on biomechanical parameters of healthy human subjects common carotid artery using a new ultrasound image processing software- based automatic method

Abstract

Background and Aims : Mechanical changes include thickening of arterial wall, alteration of arterial elasticity, contraction of smooth muscle, increase in sensitivity to pharmacological stimulation and increase in arterial viscoelasticity, i.e., arteriosclerosis. There is therefore interest in the application of non-invasive clinical tools to assess arterial biomechanical parameters. In this study, we aimed to investigate the effect of high- intensity exercise on biomechanical parameters of healthy human subjects’arteries.Methods: In this study we used a new computerized analysis method for measurement of instantaneous changes in far and near arterial walls in sequential ultrasound images. In this method, two algorithms, i.e., maximum gradient and dynamic programming, were composed and implemented. Approximately 70 sequential ultrasound images spanning three cardiac cycles were analyzed from each examination to detect instantaneous changes in the far and near walls and lumen maximum, minimum, and mean diameters.Results: from new ultrasound image processing software- based automatic method showed a significant reduction in the mean value for shear elastic modulus and a significant increase in the mean value for radial strain, compliance and distensibility index in the treatment (high intensity exercise) group compared with the other groups (P<0.05).Conclusions: Nitric Oxide (NO) is considered the most important endothelial-derived vasodilation factor. It is concluded that the administration of high- intensity exercise, can cause to enhance the endothelial NO synthase, resulting in an increase in the arterial diameter and an improvement in the arterial biomechanical parameters. Furthermore, we concluded that our new computerized automatic method is reliable to accurate and repeated evaluation of arterial biomechanical parameters. Background and Aims : Mechanical changes include thickening of arterial wall, alteration of arterial elasticity, contraction of smooth muscle, increase in sensitivity to pharmacological stimulation and increase in arterial viscoelasticity, i.e., arteriosclerosis. There is therefore interest in the application of non-invasive clinical tools to assess arterial biomechanical parameters. In this study, we aimed to investigate the effect of high- intensity exercise on biomechanical parameters of healthy human subjects’arteries. Methods: In this study we used a new computerized analysis method for measurement of instantaneous changes in far and near arterial walls in sequential ultrasound images. In this method, two algorithms, i.e., maximum gradient and dynamic programming, were composed and implemented. Approximately 70 sequential ultrasound images spanning three cardiac cycles were analyzed from each examination to detect instantaneous changes in the far and near walls and lumen maximum, minimum, and mean diameters. Results: from new ultrasound image processing software- based automatic method showed a significant reduction in the mean value for shear elastic modulus and a significant increase in the mean value for radial strain, compliance and distensibility index in the treatment (high intensity exercise) group compared with the other groups (P<0.05). Conclusions: Nitric Oxide (NO) is considered the most important endothelial-derived vasodilation factor. It is concluded that the administration of high- intensity exercise, can cause to enhance the endothelial NO synthase, resulting in an increase in the arterial diameter and an improvement in the arterial biomechanical parameters. Furthermore, we concluded that our new computerized automatic method is reliable to accurate and repeated evaluation of arterial biomechanical parameters.