Hemodynamic changes of common carotid artery in patients with moderate and severe ipsilateral internal carotid artery stenosis or occlusion

Objectives To observe the hemodynamic changes of the ipsilateral common carotid artery(CCA)in patients with moderate and severe internal carotid artery(ICA)stenosis or occlusion and to analyze the relationship between the hemodynamic changes of CCA and the degree of ICA stenosis.Methods A total of 200 patients with unilateral occlusion or 50%-99% stenosis in the extracranial segment of ICA,and normal or stenosis 50% of bilateral CCA were included in the study.The patients were divided into 50%-69%(n=50),70%-99% stenosis(n=68)and occlusion(n=82)groups according to the degree of stenosis of ICA on the affected sides.The internal diameter(ID),peak systolic velocity(PSV),end-diastolic velocity(EDV),mean velocity(MV),and resistance index(RI)of bilateral CCA were detected by color duplex sonography.The carotid blood flow volume(BFV),the peak velocity ratios of ICA and CCA on the affected sides(PSVICA/PSVCCA),and the ratios of all the CCA hemodynamic parameters on the affected and unaffected sides were calculated.Results ①The affected and unaffected sides in all groups and the ID of CCA on the affected sides were compare among all groups,there were no significant differences.②As compared with the unaffected sides,apart from increased PSVICA/PSVCCA(1.90±0.36 vs 0.88±0.23,P0.001)on the affected sides in the 50%-69% stenosis group,there were no statistical significances among other parameters.③As compared with the unaffected sides in the same group and the 50%-69% stenosis group,the PSVICA/PSVCCA and RI on the affected sides in the 70%-99% stenosis group and the occlusion group(no PSVICA/PSVCCA in the occlusion group)were increased(P0.001).The PSV,EDV,MV,and BFV were all decreased(P0.001).EDV and BFV were decreased more significantly in the 70%-99% group than those in the occlusion group,and there was statistical significance between the two groups.④As compared with the 50%-69% stenosis group,the ratios of PSV/PSV,EDV/EDV,MV/MV,and BFV/BFV in the 70%-99% stenosis group and the occlusion group were all increased(P0.05).EDV and BFV in the occlusion group were increased more significantly than those in the 70%-99% stenosis group(P0.01).⑤Logistic regression analysis showed that EDV and ICA 70%-99% stenosis(OR=0.31,95% CI,0.14-0.47,r=-0.66,P=0.001)and occlusion(OR=0.26,95% CI,0.06-0.56,r=-0.86,P=0.010)all had significant negative correlations.Conclusions When the unilateral ICA has 70%-99% stenosis or occlusion,all the ipsilateral CCA develop corresponding hemodynamics changes particularly the changes of EDV.When the stenosis is 50%-69%,only the ipsilateral PSVICA/PSVCCA elevated.