Cognitive Outcome After Carotid Surgery

The purpose of this study is to understand how carotid endarterectomy (CEA) or percutaneous carotid angioplasty and stenting (CAS) affect memory and thinking resulting in improving or worsening of thinking or memory. There have been many studies on this subject, some finding that certain patients gain improvement in their brain function and others might get worse. The goal of this study is to discover which patients are more likely to have improved cognitive functioning. Carotid endarterectomy (CEA) and percutaneous carotid angioplasty and stenting (CAS) are not investigational and are an accepted treatment for your condition. In addition, subjects that choose not to undergo surgery will also be included in this study.

Study Overview

• Status: Completed
• Conditions: Carotid Stenosis

Detailed Description

At the present time, large multi-center clinical trials support the use of carotid revascularization for symptomatic carotid stenosis and for asymptomatic carotid stenosis (greater than 60%) to prevent stroke. Guidelines supporting the use of carotid endarterectomy for asymptomatic stenosis are based largely on the Asymptomatic Carotid Atherosclerosis Study (ACAS) which reported a 47% relative risk reduction for ipsilateral stroke or death in patients randomized to surgery compared to best medical management over 5 years. These data were further substantiated by the recent publication of the Medical Research Council Asymptomatic Carotid Surgery (ACST) trial results (1); however, both trials estimated that at least 40 operative procedures were required to prevent a single disabling stroke or death in one patient after 5 years (2). These data underscore the importance of understanding the cognitive risks of carotid revascularization and developing strategies to limit factors that contribute to this risk especially in asymptomatic patients.

The purpose of this study is to better understand the effect of carotid revascularization (using either carotid endarterectomy (CEA) or percutaneous carotid angioplasty and stenting (CAS)) on cognitive outcome by prospectively collecting cerebral blood flow data and cognitive testing data prior to and after carotid revascularization procedures.

• Study Type: Observational
• Enrollment (Anticipated): 56

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Burlington, Massachusetts, United States, 01805
      • Lahey Clinic, Inc.
  • New York
    • Buffalo, New York, United States, 14203
      • University of Buffalo Neurosurgery (UBNS)
    • Stony Brook, New York, United States, 11794-8122
      • StonyBrook

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients with unilateral, asymptomatic, significant carotid artery stenosis who are ≥18 years of age who do not present with past or current significant cerebrovascular and neuropsychological disease.

Description

Inclusion Criteria:

• Patients with asymptomatic (defined as no symptoms in past 6 months) carotid stenosis
• Patients with hemodynamically significant carotid artery stenosis (according to CREST criteria: ≥ 60% by angiography, OR ≥ 70% by ultrasound, OR ≥ 80% by CTA or MRA)

Exclusion Criteria:

• Patients with prior large vessel infarct
• Patients with intracranial stenosis
• Patients with major depression
• Patients with Alzheimer disease (clinically defined or Wechsler IQ <80)
• Patients who have had previous ipsilateral carotid surgery
• Patients with baseline dementia defined as: Mini-Mental Status Examination score < 21 OR Mini-Mental score ≥21 AND Baseline HVLT scores more than 3 standard deviations below normal or FAS scores more than 2 standard deviations below normal OR other clinical symptoms that were not as evident on direct cognitive assessment (e.g. sundowning, getting lost while driving).

Note: A control group would be comprised of about 15 patients who meet eligibility criteria as above, but elect to have their condition followed rather than undergo revascularization.

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort
Carotid Endarterectomy (CEA); Surgical Revascularization- Carotid Endarterectomy (CEA)
Carotid Angioplasty and Stenting (CAS); Surgical Revascularization- Carotid Angioplasty and Stenting (CAS)
Control Group- Medical Management

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Measurement of change in cerebral blood flow from pre-op/baseline to 1 month post-operatively.	Quantitative flow MRA studies will be performed pre-operative and postoperative for those undergoing carotid revascularization surgery. Those not undergoing surgery will have this test upon study enrollment and approximately 1 month from study enrollment date.	preoperative/baseline and 1 month postoperative/from baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mini Mental Status Exam	A standardized cognitive measure	Pre-operative/baseline
Trail Making- Part A	Standardized cognitive measure that assesses verbal fluency	Preoperative/baseline, 1 month postoperative/post baseline, 6 months postoperative/post baseline, and 1 year postoperative/post baseline
Trail Making- Part B	Standardized cognitive measure that assesses executive functioning	Preoperative/baseline, 1 month postoperative/post baseline, 6 months postoperative/post baseline, and 1 year postoperative/post baseline
Hopkins Verbal Learning Test (HVLT)	Standardized measure to assess new learning and memory	Preoperative/baseline, 1 month postoperative/post baseline, 6 months postoperative/post baseline, and 1 year postoperative/post baseline
D-KEFS Verbal Fluency Test (FAS)	Standardized measure to assess letter fluency	Preoperative/baseline, 1 month postoperative/post baseline, 6 months postoperative/post baseline, and 1 year postoperative/post baseline

Collaborators and Investigators

• Sponsor: Lahey Clinic
• Investigators: Principal Investigator: Zoher Ghogawala, MD, Lahey Clinic, Inc.

Publications and helpful links

General Publications

• Halliday A, Mansfield A, Marro J, Peto C, Peto R, Potter J, Thomas D; MRC Asymptomatic Carotid Surgery Trial (ACST) Collaborative Group. Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial. Lancet. 2004 May 8;363(9420):1491-502. doi: 10.1016/S0140-6736(04)16146-1. Erratum In: Lancet. 2004 Jul 31;364(9432):416.
• Rothwell PM, Goldstein LB. Carotid endarterectomy for asymptomatic carotid stenosis: asymptomatic carotid surgery trial. Stroke. 2004 Oct;35(10):2425-7. doi: 10.1161/01.STR.0000141706.50170.a7. Epub 2004 Aug 26. No abstract available.

Study record dates

Study Major Dates

• Study Start: April 1, 2014
• Primary Completion (Actual): November 1, 2019
• Study Completion (Actual): November 1, 2019

Study Registration Dates

• First Submitted: April 15, 2014
• First Submitted That Met QC Criteria: April 16, 2014
• First Posted (Estimate): April 21, 2014

Study Record Updates

• Last Update Posted (Actual): November 26, 2019
• Last Update Submitted That Met QC Criteria: November 22, 2019
• Last Verified: March 1, 2018

More Information

Terms related to this study

• Keywords: surgery; stenosis; unilateral; cognitive; carotid
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Arterial Occlusive Diseases; Carotid Artery Diseases; Carotid Stenosis
• Other Study ID Numbers: 2013-009