Prime Research Of Cerebral Blood Flow Variation In Acute Cerebral Infarction Patients With TCD During Tilt Table Test

OBJECTIVE To explore the change of cerebral blc od flow in acute cerebral infarction patients during tilt table test and evaluate the variability of cerebral blood flow autoregulation.METHOD Cerebral blood flow in middle cerebral arteries and pulsatility index were measured with Transcranial Doppler sonography between twenty-two healthy people and twenty acute cerebral infarction patients at 0, 30and 60 head-up position. Heart rate and blood pressure were also obtained continuously from electricardiograph.RESULT 1 Heart rate quickened significantly in both control subjects and patients from 0 position to 30 and 60 position and there was no significance of difference about the extent of changing between two groups.2 There was not significantly affected by tilt in two groups. An upward trend was observed in blood pressure in the control subjects from 0 position to 60 position, whereas the patients show a downward trend.(3)The mean flow velocity in the ischemic hemisphere is higher than that of control group during tilt table test. A downward trend was observed in mean .flow velocity with increasing tilt angle in two groups(P<0.05). The changing extent of flow velocity was no significance of difference in 30 position. The decreasing extent of flow velocity in the ischemic hemisphere was greater than that of control groups in the first minute in 60 position, but there was 10 significant difference between the patients and the control subjects after four minute.(4)There was a decrease with pulsatility index(FI) in 30?position, but a incrementin 60 position in control subjects. There was a significant increment withpulsatility index in response to tilt in patients. The increasing extent of patients' PIwere greater than that of control subjects in the 60 position.(5)The flow-pressure show a negative correlation in the patients (P<0.05); however,there was no correlation in control groups. CONCLUSION Cerebral blood flow autoregulat on is impaired in acute cerebralinfarction patients. It is value for acute cerebral infarction patients to investigativethe variability of cerebral blood flow with tilt table test...