Dataset Information

Cerebrovascular reactivity predicts stroke in high-grade carotid artery disease.

ABSTRACT:

Objective

To assess the usefulness of transcranial Doppler CO2 reactivity (CO2R) for prediction of ipsilateral ischemic stroke in carotid artery stenosis and occlusion with a meta-analysis of prospective studies based on individual patient data.

Methods

We searched Medline, Biosis Previews, Science Citation Index, The Cochrane Library, and EMBASE for studies in which patients with severe carotid artery stenosis or occlusion underwent Doppler CO2R testing (inhalation of CO2 or breath-holding) and were prospectively followed for ipsilateral ischemic stroke. Individual data from 754 patients from 9 studies were included. We used percentage cerebral blood flow velocity increase (pCi) during hypercapnia as the primary CO2R measure, and defined impaired reactivity as pCi <20% increase.

Results

In a multiple regression model, impaired CO2R was independently associated with an increased risk of ipsilateral ischemic stroke (hazard ratio [HR] 3.69; confidence interval [CI] 2.01, 6.77; p < 0.0001). Risk prediction was similar for recently symptomatic vs asymptomatic patients. Using continuous values of pCi, a significant association between decreasing pCi and increasing risk of ipsilateral stroke was found: HR of 1.64 (95% CI 1.33, 2.02; p < 0.0001) per 10% decrease in pCi. For patients with asymptomatic internal carotid artery stenosis only (n = 330), a comparable stroke risk prediction was found: increasing HR 1.95 (95% CI 1.26, 3.04; p = 0.003) per 10% decrease in pCi.

Conclusions

This analysis supports the usefulness of CO2R in risk prediction for patients with severe carotid artery stenosis or occlusion, both in recently symptomatic and asymptomatic patients. Further studies should evaluate whether treatment strategies in asymptomatic patients based on CO2R could improve patient outcomes.

SUBMITTER: Reinhard M

PROVIDER: S-EPMC4206163 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Publications

Cerebrovascular reactivity predicts stroke in high-grade carotid artery disease.

Reinhard Matthias M Schwarzer Guido G Briel Matthias M Altamura Claudia C Palazzo Paola P King Alice A Bornstein Natan M NM Petersen Nils N Motschall Edith E Hetzel Andreas A Marshall Randolph S RS Klijn Catharina J M CJ Silvestrini Mauro M Markus Hugh S HS Vernieri Fabrizio F

Neurology 20140912 16

<h4>Objective</h4>To assess the usefulness of transcranial Doppler CO2 reactivity (CO2R) for prediction of ipsilateral ischemic stroke in carotid artery stenosis and occlusion with a meta-analysis of prospective studies based on individual patient data.<h4>Methods</h4>We searched Medline, Biosis Previews, Science Citation Index, The Cochrane Library, and EMBASE for studies in which patients with severe carotid artery stenosis or occlusion underwent Doppler CO2R testing (inhalation of CO2 or brea ...[more]

PMID: 25217057

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Dataset Information

Cerebrovascular reactivity predicts stroke in high-grade carotid artery disease.

Objective

Methods

Results

Conclusions

Publications

Cerebrovascular reactivity predicts stroke in high-grade carotid artery disease.

Similar Datasets

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