title: Microembolization is associated with transient cognitive decline in patients undergoing carotid interventions.
abstract: OBJECTIVE
  Carotid interventions are important in helping to reduce the risk of stroke for patients with high-grade carotid artery stenosis; however, subclinical cerebral microemboli can occur during these procedures. Associations have been found between the incidence of microemboli and postoperative decline in memory. We therefore sought to determine whether this decline persisted long-term and to assess changes in other cognitive domains.
  
  
  METHODS
  Patients were prospectively recruited under an Institutional Review Board-approved protocol at a single academic center. Neuropsychological testing was administered preoperatively and at 1-month and 6-month intervals postoperatively. Cognitive domains that were evaluated included verbal memory, visual memory, psychomotor speed, dexterity, and executive function. Diffusion-weighted magnetic resonance imaging sequencing was performed preoperatively and ≤48 hours postoperatively to identify procedure-related microemboli. Univariate and multivariate regression models were used to identify relationships among microembolization, demographics, and cognition.
  
  
  RESULTS
  Included were 80 male patients with an average age of 69 years. Forty patients underwent carotid artery stenting and 40 underwent carotid endarterectomy. Comorbidities included diabetes in 45%, coronary artery disease in 50%, and prior neurologic symptoms in 41%. New postoperative microemboli were found in 45 patients (56%). Microembolization was significantly more common in the carotid artery stenting cohort (P < .005). Univariate analysis demonstrated that patients with procedurally related embolization showed decline 1 month postoperatively in verbal memory and Trail Making A measures. Multivariate analysis demonstrated that procedurally related embolization (odds ratio [OR], 2.8; P = .04) and preoperative symptomatic stenosis (OR, 3.2; P = .026) were independent predictors of decline for the Rey Auditory Verbal Learning Test Short Delay measure at 1 month. At 6 months, no significant relationship was found between emboli and decline on Rey Auditory Verbal Learning Test Short Delay, but age (OR, 1.1, P = .005) and chronic obstructive pulmonary disease (OR, 7.1, P = .018) were significantly associated with decline at 6 months after the intervention.
  
  
  CONCLUSIONS
  Microembolization that is associated with carotid artery intervention predicts short-term cognitive decline. However, some of these cognitive deficits persist at 6 months after the intervention, and further investigation is warranted to determine individual patient risk factors that may affect recovery.
authors.affiliation: Division of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hitchner
authors.affiliation: Division of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif.
authors.forename: Brittanie D
authors.initials: BD
authors.lastname: Baughman
authors.affiliation: Department of Neuroradiology, Harvard School of Medicine, Cambridge, Mass.
authors.forename: Salil
authors.initials: S
authors.lastname: Soman
authors.affiliation: Division of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif.
authors.forename: Becky
authors.initials: B
authors.lastname: Long
authors.affiliation: Division of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif.
authors.forename: Allyson
authors.initials: A
authors.lastname: Rosen
authors.affiliation: Division of Vascular Surgery, VA Palo Alto Health Care System, Palo Alto, Calif; Division of Vascular Surgery, Stanford University, Stanford, Calif. Electronic address: weizhou@stanford.edu.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
mesh_terms: D000046:Academic Medical Centers; D000368:Aged; D000369:Aged, 80 and over; D017130:Angioplasty / Q000009:adverse effects* / Q000295:instrumentation; D002140:California; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*; D003071:Cognition; D003072:Cognition Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000523:psychology; D038524:Diffusion Magnetic Resonance Imaging; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D056344:Executive Function; D006801:Humans; D020766:Intracranial Embolism / Q000000981:diagnostic imaging / Q000209:etiology* / Q000523:psychology; D016015:Logistic Models; D008297:Male; D008568:Memory; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011597:Psychomotor Performance; D020127:Recovery of Function; D012307:Risk Factors; D012720:Severity of Illness Index; D015607:Stents; D013997:Time Factors; D014145:Trail Making Test; D016896:Treatment Outcome; D014705:Verbal Behavior