Prospective neurocognitive evaluation of patients undergoing carotid interventions.
OBJECTIVE
Distal cerebral embolization is a known complication of carotid interventions. We prospectively investigated whether subclinical microembolization seen on postoperative magnetic resonance imaging (MRI) leads to cognitive deficits in patients undergoing carotid revascularization procedures.


METHODS
Patients undergoing carotid interventions and eligible for MRI scanning were recruited. Among 247 patients who received preoperative and postoperative MRI evaluations, 51 also completed neuropsychologic testing before and at 1 month after their procedure. Cognitive evaluation included the Rey Auditory Verbal Learning Test (RAVLT) for memory evaluation and the Mini-Mental State Examination (MMSE) for general cognitive impairment screening.


RESULTS
The 51 patients (all men), comprising 16 with carotid artery stenting (CAS) and 35 with carotid endarterectomy (CEA), were a mean age of 71 years (range, 54-89 years). Among them, 27 patients (53%) were symptomatic preoperatively, including 11 who had prior stroke and 16 who had prior preoperative transient ischemic attack symptoms. Most patients had significant medical comorbidities, including hypertension (96%), diabetes (31.3%), coronary artery disease (47%), and chronic obstructive pulmonary disease (15.7%). Two patients (4%) had prior ipsilateral CEA and eight had contralateral carotid occlusion (15.7%). Memory decline evident on RAVLT was identified in eight CAS patients and 13 CEA patients. Eleven patients had evidence of procedure-related microemboli. Although there was no significant difference in baseline cognitive function or memory change between the CEA and CAS cohorts, the CAS cohort had a significantly higher incidence of microembolic lesions. Multivariate regression analysis showed that procedure-related microembolization was associated with memory decline (P = .016) as evident by change in RAVLT. A history of neurologic symptoms was significantly associated with poor baseline cognitive function (MMSE; P = .03) and overall cognitive deterioration (change in MMSE; P = .026), as determined by Wilcoxon rank sum test and linear regression analysis, respectively.


CONCLUSIONS
Although CEA and CAS are effective in stroke prevention, with minimal neurologic complication, neurocognitive effects remain uncertain. Procedure-associated microembolization and pre-existing neurologic symptoms are associated with poor baseline cognitive function and memory decline after the procedures. Further comprehensive cognitive evaluation to determine the benefit of carotid interventions is warranted.
Department of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, CA, USA. weizhou@stanford.edu
Wei
W
Zhou
Elizabeth
E
Hitchner
Kathleen
K
Gillis
Lixian
L
Sun
Rebecca
R
Floyd
Barton
B
Lane
Allyson
A
Rosen
D000368:Aged; D000369:Aged, 80 and over; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects; D016893:Carotid Stenosis / Q000175:diagnosis / Q000523:psychology* / Q000601:surgery*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology; D016894:Endarterectomy, Carotid / Q000009:adverse effects; D057510:Endovascular Procedures / Q000009:adverse effects; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D012307:Risk Factors