The effect of hemodynamic factor on the level of tangential stress of the artery wall in the zone of carotid bifurcation

Backgraund. The most common source of the development of acute and chronic forms of cerebrovascular accident is atherosclerosis of the bifurcation zone of the common carotid artery and of the mouth of the internal carotid artery. Namely, the processes occurring in this zone can cause a significant number of the heart attacks of the cerebral hemispheres. The aim of the study was to improve the treatment results of patients with atherosclerotic lesions of carotid vessels by increasing the accuracy of predicting the risk of embologenic rupture of carotid artery plaque. Materials and methods. 12 patients with atherosclerosis of the brachiocephalic arteries with a maximum 60% stenosis degree were included into the study. All patients were examined with Doppler ultrasound and spiral computed tomography-angiography of the carotid arteries. The data of investigations were used to calculate the values of tangential and equivalent stresses, as well as the cyclic deformation of the vascular wall using the universal software system of finite element analysis ANSYS (ANSYS Inc., USA). Results. During mathematical analysis the critical values of shear stress, equivalent stress, and cyclic deformations revealed, the excess of which, with a systolic blood pressure of 160 mm Hg and below, will be accompanied by acute cerebrovascular accident. These values were tangential stress indices equal to or higher than 1.5 kPa, equivalent stress equal to or greater than 0.068032 mPA and cyclic strain equal to or greater than 0.00070864 conv. Conclusion. The completed draft guide is expecting to produce gives hope for creating a convenient and reliable method for predicting the risk of embologenic rupture of atherosclerotic plaque of the carotid artery, which will allow surgical or endovascular intervention within the given timeframe to prevent the occurrence of acute cerebrovascular accident.