Analysis of Hemodynamic Changes in Early Stage after Carotid Stenting by Transcranial Doppler-A Preliminary Study.

BACKGROUND

Cerebral hyperperfusion syndrome or hemodynamic instability, caused by the hemodynamic changes, often occur within 6 hr after carotid artery stenting (CAS) The postprocedure cerebral hemodynamic change in the early phase, <6 hr after CAS, is largely unknown. In this study, we evaluated the cerebral hemodynamic changes in patients after CAS using transcranial Doppler (TCD).

METHODS

From January 2013 to July 2014, medical records of 61 patients who underwent CAS were reviewed retrospectively. Among them, 44 patients had TCD examination before CAS, 1-2 and 3-4 hr after CAS. In the TCD examination, middle cerebral artery (MCA) peak systolic velocity (PSV) and pulsatility index (PI) on the ipsilateral and contralateral sides were measured. Blood pressure, MCA PSV, and PI data were collected and analyzed from the 44 patients who had valid TCD examinations.

RESULTS

Blood pressure was 148.4 ± 14.5 mm Hg before CAS: 124.5 ± 13.8 mm Hg 1-2 hr after CAS, and 121.6 ± 12.6 mm Hg 3-4 hr after CAS. On the ipsilateral side, the MCA PSV increased from 85.7 ± 22.8 cm/s before CAS to 101.1 ± 27.1 cm/s (19.9%, P < 0.001) 1-2 hr after CAS, and 99.7 ± 27.0 cm/s (18.2%, P < 0.001) 3-4 hr after CAS. There was no significant difference in MCA PSV between 1-2 and 3-4 hr after CAS (P = 0.200). The PI increased from 0.871 ± 0.167 before CAS to 0.941 ± 0.205 (P = 0.022) 1-2 hr after CAS, and 0.954 ± 0.218 (P = 0.010) 3-4 hr after CAS. On the contralateral side, there was no statistically significant PSV increase in the MCA following CAS.

CONCLUSIONS

CAS may induce a significant increase in PSV and PI in the ipsilateral MCA within 4 hr. The MCA PSV increased significantly higher than that on the contralateral side. The PSV had no significant change between 1-2 and 3-4 hr after CAS.