Improvement of neurocognitive function after protected carotid artery stenting

Abstract

To investigate the effect of protected carotid artery stenting on neurocognitive function with particular consideration of the angiographic filling of the ipsilateral anterior cerebral artery (ACA). An improved inflow to the supply area of the anterior cerebral artery after revascularisation of severe carotid artery stenosis may beneficially affect frontal lobe cognitive functions. We prospectively included 71 consecutive patients who underwent carotid artery stenting (CAS) due to high grade carotid artery stenosis. Intracranial angiograms and filling status of the ACA pre- and post-stenting were analyzed and a battery of 5 selected neuropsychological tests for frontal lobe function were applied prior to and 6 months after CAS. Patients with improvement in at least two tests were defined as having improved neurocognitive function. Compared to baseline, we found a significant improvement of the Trail-Making Test A (median 6% improved change-score; P = 0.01), the test of supermarket items showed a trend towards significant improvement (median 3.7% improved change-score; P = 0.09). In 32 patients (45%) an improvement of at least 2 neurocognitive tests was observed. Neuropsychological improvement was found more frequently in patients with a contrasted ipsilateral ACA after CAS (88%, 95% CI 77 to 99) compared to patients without angiographic filling of the ipsilateral ACA post CAS (13%, 95% CI 1 to 25), respectively (P < 0.01). Carotid artery stenting improves neurocognitive function in a considerable proportion of patients. A contrasted ipsilateral anterior cerebral artery after CAS is associated with improved neurocognitive function, presumably due to amelioration of frontal lobe perfusion.