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Time to rethink management strategies in asymptomatic carotid artery disease

Nature Reviews Cardiology volume 9, pages 116–124 (2012)Cite this article

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Abstract

Despite level I evidence, no worldwide consensus of opinion exists on how best to manage patients with asymptomatic carotid artery disease. In this article, I present the evidence supporting intervention in these patients, highlighting a number of 'inconvenient truths' that challenge the current 'one size fits all' approach to treatment. I will demonstrate that, even if one could identify and treat every individual with a 60–99% asymptomatic stenosis, >95% of all strokes will still occur. Evidence shows that 94% of all carotid endarterectomy and carotid artery stenting procedures in asymptomatic patients in the US are ultimately unnecessary, costing health-care providers US$2 billion annually. Evidence also exists that the risk of stroke in patients treated medically is lower than when the asymptomatic trials were recruiting, challenging the appropriateness of basing contemporary guidelines upon historical data. A small cohort of 'high-risk for stroke' patients will undoubtedly benefit from intervention and our goal must be to identify and treat these individuals, rather than continuing with a policy of mass intervention that benefits very few patients in the long term.

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Figure 1: Annual rates of stroke in medically treated patients with asymptomatic carotid stenosis stratified for year of publication and baseline severity of stenosis.3,4,5,44,45,54,55,58,59,60,61,62,63,64,65,66,67,68,69,78
Figure 2: Prediction of annual risk of late stroke in patients with a | 50–79% or b | 80–99% asymptomatic carotid stenosis.

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  1. Division of Cardiovascular Sciences, Clinical Sciences Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE2 7LX, UK

    A. Ross Naylor

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Naylor, A. Time to rethink management strategies in asymptomatic carotid artery disease. Nat Rev Cardiol 9, 116–124 (2012). https://doi.org/10.1038/nrcardio.2011.151

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