Background. Endarterectomy (CEA) or stenting (CAS) of a stenotic carotid artery is currently undertaken to reduce stroke risk. In addition removal of the arterial narrowing has been hypothesized to improve cerebral hemodynamics and provide benefits in cognitive functions, by supposedly resolving a “hypoperfusion” condition. Methods. In this study we sought to test whether resolution of a carotid stenosis is followed by measurable changes in cognitive functions in 22 subjects with “asymptomatic” stenosis. Results. A main finding of the study was the statistically significant pre-post difference observed in the performance of phonological verbal fluency and Rey’s 15-word immediate recall. Remarkably, there was a significant interaction between phonological verbal fluency performance and side of the carotid intervention, as the improvement in the verbal performance, a typical “lateralized” skill, was associated with resolution of the left carotid stenosis. Conclusion. The results reflect a substantial equivalence of the overall performance at the before- and after- CEA or CAS tests. In two domains, however, the postintervention performance resulted improved. The findings support the hypothesis that recanalization of a stenotic carotid could improve brain functions by resolving hypothetical “hypoperfusion” states, associated with the narrowing of the vessels. 1. Introduction Asymptomatic patients with substantial (i.e., 60%–90%) carotid artery narrowing, but no recent neurological symptoms, are at increased long-term risk of ischemic stroke, especially in areas of the brain supplied by the artery. Endarterectomy (CEA) or stenting (CAS) of the carotid artery removes the arterial narrowing, but the procedure itself causes immediate risk of stroke or death. It is object of a long-lasting debate to establish whether the risk overcomes what seems to be a substantial reduction of nonperioperative stroke over a 10-year period following CEA [1]. Improvements in stroke prevention obtained by medical treatment alone and care, in the last few years, seem to support conservative approaches in asymptomatic subjects [2, 3]. The debate is still ongoing [4]. A side aspect, consistently dismissed in clinical settings, concerns the notion that CEA or CAS may improve brain functions by resolving a hypothetical “hypoperfusion” state, associated with narrowing of the vessels [5–7]. The hypothesis has been probably underestimated for long time, as supportive data were essentially of anecdotal nature. A number of case reports have shown improvement in cognitive impairment
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