Correlation between hemodynamics, blood pressure variability and severity of carotid artery stenosis in patients with transient ischemic attack

Objective To investigate the relationship between hemodynamics, blood pressure variability and severity of carotid artery stenosis in patients with transient ischemic attack(TIA). Methods Totally 180 patients with TIA were divided into control group(n=80), mild stenosis group(n=36), moderate stenosis group(n=34)and severe stenosis group(n=30)according to the severity of carotid stenosis. The relationship between hemodynamics, blood pressure variability and severity of carotid stenosis was analyzed. Results The systolic peak velocity(PSV), diastolic peak velocity(EDV)and mean velocity(MV)in mild and moderate stenosis groups were significantly lower than those in the control group, and the pulsation index(PI)and resistance index(RI)were significantly - higher than those in the control group(P<0.05). The levels of PSV, EDV and MV in severe stenosis group were significantly lower than those in mild and moderate stenosis groups, and the levels of PI and RI were significantly higher than those in mild and moderate stenosis groups(P<0.05). The 24-hour systolic blood pressure standard deviation(24 h SSD), 24-hour diastolic blood pressure standard deviation(24 h DSD), daytime systolic blood pressure standard deviation(dSSD), daytime diastolic blood pressure standard deviation(dDSD), nighttime systolic blood pressure standard deviation(nSSD)in mild and moderate stenosis groups were significantly higher than those in the control group(P<0.05). The above indexes in moderate and severe stenosis groups were significantly higher than those in mild stenosis groups(P<0.05), and those in severe stenosis group were significantly higher than moderate stenosis group(P<0.05). There was no significant difference in nighttime diastolic blood pressure standard deviation(nDSD)among the four groups(P>0.05). The proportion of patients with dipper rhythm in mild and moderate stenosis groups was significantly lower than that in the control group, and the proportion of patients with non-dipper rhythm was significantly higher than that in the control group(P<0.05). The proportion of patients with dipper rhythm in severe stenosis group was significantly lower than that in mild and moderate stenosis groups, and proportion of patients with non-dipper rhythm group was significantly higher than that in mild and moderate stenosis groups(P<0.05). There were no significant differences in proportions of patients with over-dipper and anti-dipper rhythm among the four groups(P>0.05). The intima-media thickness(IMT)value, total incidence of plaque and total score of plaque in the mild and moderate stenosis groups were significantly higher than those in the control group(P<0.05). The IMT value, total incidence of plaque and total score of plaque in the severe stenosis group were significantly higher than those in the mild and moderate stenosis groups(P<0.05). The average cerebral blood flow in the mild and moderate stenosis groups was significantly lower than that in the control group, and the total detection rates of intracranial stenosis, vertebrobasilar artery stenosis, subclavian steal syndrome and extracranial transcranial occlusion were significantly higher than those in the control group(P<0.05). The average cerebral blood flow in the severe stenosis group was significantly lower than that in the mild and moderate stenosis groups, and the total detection rate was significantly higher than that in the mild and moderate stenosis groups(P<0.05). Pearson correlation analysis showed that the degree of carotid stenosis was significantly correlated with PSV, EDV, MV, 24 h SSD, 24 h DSD, dSSD, dDSD and nSSD(P<0.05), and was negatively correlated with PI and RI(P<0.05). Conclusion Hemodynamics, blood pressure variability, plaque changes and mean cerebral blood flow are related to the severity of carotid stenosis, which is of great significance for the diagnosis of TIA.