Cerebrovascular Reserve and Stroke Risk in Patients With Carotid Stenosis or Occlusion: A Systematic Review and Meta-Analysis

Background and Purpose— Impairments in cerebrovascular reserve (CVR) have been variably associated with increased risk of ischemic events and may stratify stroke risk in patients with high-grade internal carotid artery stenosis or occlusion. The purpose of this study is to perform a systematic review and meta-analysis to summarize the association of CVR impairment and stroke risk. Methods— We performed a literature search evaluating the association of impairments in CVR with future stroke or transient ischemic attack in patients with high-grade internal carotid artery stenosis or occlusion. We included studies with a minimum of 1-year patient follow-up with baseline CVR measures performed by any modality and primary outcome measures of stroke and/or transient ischemic attack. A meta-analysis with assessment of study heterogeneity and publication bias was performed. Results were presented in a forest plot and summarized using a random-effects model. Results— Thirteen studies met the inclusion criteria, representing a total of 1061 independent CVR tests in 991 unique patients with a mean follow-up of 32.7 months. We found a significant positive relationship between impairment of CVR and development of stroke with a pooled random effects OR of 3.86 (95% CI, 1.99–7.48). Subset analysis showed that this association between CVR impairment and future risk of stroke/transient ischemic attack remained significant regardless of ischemic outcome measure, symptomatic or asymptomatic disease, stenosis or occlusion, or CVR testing method. Conclusions— CVR impairment is strongly associated with increased risk of ischemic events in carotid stenosis or occlusion and may be useful for stroke risk stratification.

[1]  Makoto Isozaki,et al.  Clinical implication and prognosis of normal baseline cerebral blood flow with impaired vascular reserve in patients with major cerebral artery occlusive disease , 2010, Annals of nuclear medicine.

[2]  K. Furie,et al.  Update to the AHA/ASA recommendations for the prevention of stroke in patients with stroke and transient ischemic attack. , 2008, Stroke.

[3]  B. Widder,et al.  Course of Carotid Artery Occlusions With Impaired Cerebrovascular Reactivity , 1992, Stroke.

[4]  C Caltagirone,et al.  Impaired cerebral vasoreactivity and risk of stroke in patients with asymptomatic carotid artery stenosis. , 2000, JAMA.

[5]  T. Yoshimoto,et al.  Use of Cerebrovascular Reactivity in Patients with Symptomatic Major Cerebral Artery Occlusion to Predict 5-Year Outcome: Comparison of Xenon-133 and Iodine-123-IMP Single-Photon Emission Computed Tomography , 2002, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[6]  N. Laird,et al.  Meta-analysis in clinical trials. , 1986, Controlled clinical trials.

[7]  N. Bornstein,et al.  Does Impaired Cerebrovascular Reactivity Predict Stroke Risk in Asymptomatic Carotid Stenosis?: A Prospective Substudy of the Asymptomatic Carotid Emboli Study , 2011, Stroke.

[8]  P M Rossini,et al.  Outcome of carotid artery occlusion is predicted by cerebrovascular reactivity. , 1999, Stroke.

[9]  H. Markus,et al.  Severely impaired cerebrovascular reactivity predicts stroke and TIA risk in patients with carotid artery stenosis and occlusion. , 2001, Brain : a journal of neurology.

[10]  R. Peto,et al.  Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial , 2004, The Lancet.

[11]  C. Tulleken,et al.  Symptomatic carotid artery occlusion. A reappraisal of hemodynamic factors. , 1997, Stroke.

[12]  A. Lachaux,et al.  Asymptomatic patients. , 1988, Hepatology.

[13]  N. Bornstein,et al.  Is impaired cerebral vasomotor reactivity a predictive factor of stroke in asymptomatic patients? , 1996, Stroke.

[14]  William J Powers,et al.  Extracranial-intracranial bypass surgery for stroke prevention in hemodynamic cerebral ischemia: the Carotid Occlusion Surgery Study randomized trial. , 2011, JAMA.

[15]  H Yonas,et al.  Compromised cerebral blood flow reactivity is a predictor of stroke in patients with symptomatic carotid artery occlusive disease. , 1995, Journal of vascular surgery.

[16]  Kiyohiro Houkin,et al.  Long-Term Prognosis of Medically Treated Patients With Internal Carotid or Middle Cerebral Artery Occlusion: Can Acetazolamide Test Predict It? , 2001, Stroke.

[17]  C. Weiller,et al.  Cerebral dysautoregulation and the risk of ischemic events in occlusive carotid artery disease , 2008, Journal of Neurology.

[18]  N. Bornstein,et al.  Long‐term follow‐up of patients with asymptomatic occlusion of the internal carotid artery with good and impaired cerebral vasomotor reactivity , 2010, European journal of neurology.

[19]  D. Sackett,et al.  Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. , 1991, The New England journal of medicine.

[20]  J. Ioannidis,et al.  The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration , 2009, Annals of Internal Medicine [serial online].

[21]  Robert D. Brown,et al.  Population-Based Study of Symptomatic Internal Carotid Artery Occlusion: Incidence and Long-Term Follow-Up , 2004, Stroke.

[22]  R. Holloway,et al.  Carotid endarterectomy--an evidence-based review: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. , 2005, Neurology.

[23]  T. Momose,et al.  Reduced vascular reserve measured by stressed single photon emission computed tomography carries a high risk for stroke in patients with carotid stenosis. , 2006, International angiology : a journal of the International Union of Angiology.