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

Abstract

Cerebral hyperperfusion syndrome or hemodynamic instability, caused by the hemodynamic changes, often occur within 6hr after carotid artery stenting (CAS) The postprocedure cerebral hemodynamic change in the early phase, <6hr after CAS, is largely unknown. In this study, we evaluated the cerebral hemodynamic changes in patients after CAS using transcranial Doppler (TCD). 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 3-4hr 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. Blood pressure was 148.4±14.5mm Hg before CAS: 124.5±13.8mm Hg 1-2hr after CAS, and 121.6±12.6mm Hg 3-4hr after CAS. On the ipsilateral side, the MCA PSV increased from 85.7±22.8cm/s before CAS to 101.1±27.1cm/s (19.9%, P<0.001) 1-2hr after CAS, and 99.7±27.0cm/s (18.2%, P<0.001) 3-4hr after CAS. There was no significant difference in MCA PSV between 1-2 and 3-4hr after CAS (P=0.200). The PI increased from 0.871±0.167 before CAS to 0.941±0.205 (P=0.022) 1-2hr after CAS, and 0.954±0.218 (P=0.010) 3-4hr after CAS. On the contralateral side, there was no statistically significant PSV increase in the MCA following CAS. CAS may induce a significant increase in PSV and PI in the ipsilateral MCA within 4hr. The MCA PSV increased significantly higher than that on the contralateral side. The PSV had no significant change between 1-2 and 3-4hr after CAS.