New brain lesions after carotid revascularization are not associated with cognitive performance

Purpose: Carotid angioplasty and stenting (CAS) is increasingly being used as a treatment alternative to endarterectomy (CEA) for patients with significant carotid stenosis. However, diffusion-weighted imaging (DWI) has indicated that CAS is associated with a significantly higher burden of microemboli. This study evaluated the potential effect on intellectual functions of new DWI lesions after CEA or CAS. Methods: This prospective study analyzed the neuropsychologic outcomes after revascularization in 24 CAS and 31 CEA patients with severe carotid stenosis compared with a control group of 27 healthy individuals. All patients underwent clinical examinations, magnetic resonance imaging scans, and a neuropsychologic test battery that assessed six major cognitive domains performed immediately before CEA or CAS, <= 72 hours after, and at 3 months. Results: New DWI lesions were detected among 15 of 21 (71%) of the CAS patients immediately after treatment but in only 1 of the 28 CEA patients (4%; P < .01). As a group, patients with new DWI lesions showed a decline in their performance in the cognitive domains, attention, and visuoconstructive functions within 72 hours of carotid revascularization. Individually, however, in none of the cognitive domains did the decreases reach a clinically relevant threshold of z < -1.5. Moreover, the cognitive performance was not significantly different between patients with and without new DWI lesions 3 months after treatment. The cognitive performance was similar between CEA and CAS patients at all points. Conclusions: The findings support the assumption that new brain lesions, as detected with DWI after CAS or CEA, do not affect cognitive performance in a manner that is long-lasting or clinically relevant. Despite the higher embolic load detected by DWI, CAS is not associated with a greater cognitive decline than CEA. (J Vasc Surg 2011;53:61-70.)