Spatial distribution of wall shear stress in the common carotid artery of type 2 diabetes mellitus patients

Abstract

Objective To investigate the wall shear stress(WSS) in the common carotid artery of type 2 diabetes mellitus(DM) patients,and analyzed the spatial distribution of WSS by using quantitative visualization of blood flow shear stress analysis software.Methods Eighteen male type 2 DM subjects were enrolled as DM group and 18 age-matched healthy subjects were selected as control group.None of the participants was hypertensive,hyperlipidemic or a cigarette smoker.Intimal-medial thickness (IMT),number and size of plaques in the common carotid artery were evaluated by high-resolution echo-Doppler.Color Doppler flow images of common carotid arteries in the two groups were extracted from DICOM files.WSS in the common carotid arteries was calculated by shear stress visualization quantitative analysis software,and the corresponding spatial distribution maps of WSS were designed.Results WSS of the common carotid arteries in the control group were ranged from 4 to 14 dyne/cm2.WSS of the common carotid arteries in the DM group were ranged from 2 to 8 dyne/cm2.Compared to mean WSS value [(6.96 ± 1.17)dyne/cm2] of common carotid arteries in the control group,mean WSS value [(3.14 ± 0.79)dyne/cm2] of common carotid arteries in the DM group was significantly lower (t =9.380,P =0.000).Six diabetic participants had a plaque in one carotid artery and no lesions in the contralateral carotid.Among these subjects,mean WSS was significantly lower in the side with lesion (t =7.324,P =0.000).Therefore,IMT of common carotid arteries in participants was significantly inversely related to WSS (r =-0.76,P ＜0.01).Conclusions The common carotid arteries of DM patients are more prone to atherosclerosis which is associated with reduction of WSS.The hemodynamic profile might represent an additional factor contributing to the increased prevalence and severity of carotid atherosclerosis in diabetic patients compared with general population. Key words: Ultrasonography; Diabetes mellitus,type 2; Carotid artery,common; Wall shear stress