Short- and long-term hemodynamic and clinical effects of carotid artery stenting

Abstract

Background and purpose: Stenosis of the carotid artery may cause reduced hemodynamic and neural function that may be ameliorated with CAS. The goal of this study was to evaluate short- and long-term hemodynamic and clinical effects after CAS.

Materials and methods: Hemodynamic parameters were acquired by PCT within 1 week before CAS and at 1 week and 1 year (10-13 months) after CAS. In ACA territory, MCA territory, PCA territory, basal ganglia, anterior and posterior CWS and IWS, the rCBF, rCBV, and rMTT were determined in 20 patients with unilateral carotid artery stenosis who underwent CAS. MR and noncontrast CT were performed within 1 week before CAS. Noncontrast CT and carotid arteriography were performed immediately after CAS. Carotid arteriography was performed 1 year after CAS. MRS was performed in 3 measurements. The variance analysis was performed to determine whether there were significant differences among the 3 measurements.

Results: No significant differences were found among rCBV in any territory (P > .05). In the non-PCA territories, rMTT decreased and rCBF increased at 1 week after CAS (P < .01), but there was no significant difference between 1-week and 1-year effects (P > .05). For MR spectroscopy, no significant differences were found between 1 week after CAS and pretreatment (P > .05); the 1-year scores improved significantly (P < .01).

Conclusions: The long-term hemodynamic and clinical results after treatment validated that CAS is a durable procedure. The 1-week hemodynamic effects can predict long-term effects.

Fig 1.

The ROIs of the 2 slabs in bilateral hemispheres. ROI maps show the level of the basal ganglia (A), including ACA territory (1–2), MCA territory (3–6), PCA territory (7–8), basal ganglia (9–10), anterior CWS (11–12), and posterior CWS (13–14); and also show the level of the body lateral cerebral ventricle (B), including ACA territory (15–16), MCA territory (17–22), PCA territory (23–24), anterior CWS (25–26), posterior CWS (27–28), and IWS (29–34).

Fig 2.

95% stenosis (A) of right carotid artery in a patient aged 71 years and basically normal (B) after CAS.

Fig 3.

On the level of the basal ganglia (left) and the body lateral cerebral ventricle (right), CBF is decreased before CAS in the right hemisphere (A, B); CBF in the affected hemisphere is improved significantly at 1 week after CAS (C, D); at 1 year after CAS, CBF is similar to that shown at 1 week after CAS (E, F).

Fig 4.

On the level of the basal ganglia (left) and the body lateral cerebral ventricle (right), MTT is increased before CAS in the right hemisphere compared with the left hemisphere (A, B). This hemispheric difference disappeared at 1 week after CAS (C, D); compared with 1 week after CAS, no hemodynamic changes were found at 1 year after CAS (E, F).

Fig 5.

On the level of the basal ganglia (left) and the body lateral cerebral ventricle (right), CBV is decreased before CAS in the right hemisphere (A, B); this hemispheric difference has not disappeared at 1 week after CAS (C, D) or at 1 year after CAS (E, F).