Cerebral hemodynamic changes after carotid angioplasty and stenting.

BACKGROUND AND PURPOSE

Carotid angioplasty stent placement (CAS) is an accepted alternative to endarterectomy. However, little is known about its effect on cerebral hemodynamics. We prospectively studied the early and delayed hemodynamic changes after CAS.

MATERIALS AND METHODS

Sixty patients underwent CAS for >or=70% internal carotid artery stenosis. Transcranial Doppler (TCD) was done before, 6 hours, and 30 days after CAS. Cerebrovascular reserve to apnea (CVR) was measured.

RESULTS

On the ipsilateral side, basal middle cerebral artery (MCA) middle flow velocity (MFV) and pulsatility index (PI) increased from 49.7 cm/s and 0.85, respectively, to 62.5 cm/s and 1.09 immediately after CAS (P < .05); anterior cerebral artery (ACA) MFV and PI increased from 50.7 cm/s and 0.90, to 58.9 cm/s and 1.08 (P < .05); and posterior cerebral artery (PCA) MFV decreased from 47.5 to 36.5 cm/s, with no change in PI (P < .05). On the contralateral side, nonsignificant changes were seen on MCA, immediately after CAS; ACA and PCA MFV decreased from 63.7 and 45.3 cm/s to 50.3 and 38.6 cm/s, respectively (P < .05); ACA and PCA PI increased from 0.96 and 1.00, respectively, to 1.04 and 1.04 (P < .05). At 30 days, ipsilateral MCA MFV and PI were 52.8 cm/s and 1.12, respectively (P < .05), and contralateral values were 49.6 cm/s (P < .05) and 1.02 (nonsignificant), respectively. Basal ipsilateral and contralateral CVR improved from 26.0% to 37.0% (P < .05), and from 30.1% to 33.5% (nonsignificant), respectively, at 30 days.

CONCLUSIONS

CAS produces an early significant increase of MFV and PI in the ipsilateral anterior circulation. This effect is maintained, though minor, 30 days later. In addition, CAS results in an improvement of CVR at 30 days.