Key Points
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The mechanisms of stroke in atrial fibrillation are not well understood; fibrotic atrial tissue might directly mediate thromboembolism in stroke, independent of the atrial rhythm
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Current stroke risk scores for atrial fibrillation are suboptimal predictors of stroke
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Novel clinical risk factors, serum biomarkers, and imaging findings of atrial pathology are associated with increased risk of embolic stroke
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Identification of novel markers might be useful in weighing the risks and benefits of anticoagulation in patients who are categorized at low or intermediate risk by standard risk scores
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A subset of patients at high risk of stroke might benefit from anticoagulation even in the absence of atrial fibrillation
Abstract
Atrial fibrillation (AF) is a complex phenomenon associated with electrical, mechanical, and structural abnormalities of the atria. Ischaemic stroke in AF is only partially understood, but the mechanisms are known to be related to the atrial substrate as well as the atrial rhythm. The temporal dissociation between timing of AF and occurrence of stroke has led to the hypothesis that fibrotic, prothrombotic atrial tissue is an important cause of thrombus formation in patients with AF, independent of the atrial rhythm. Current stroke risk scores are practical, but limited in their capacity to predict stroke risk accurately in individual patients. Stroke prediction might be improved by the addition of emerging risk factors, many of which are expressions of atrial fibrosis. The use of novel parameters, including clinical criteria, biomarkers, and imaging data, might improve stroke risk prediction and inform on optimal treatment for patients with AF and perhaps individuals only at risk of AF.
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The authors acknowledge Martin E. Goldman (The Mount Sinai Hospital, New York, USA) for inspiring the manuscript.
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B.W.C. researched data for the article and wrote the manuscript. All the authors discussed the content, and reviewed and edited the manuscript before submission.
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Calenda, B., Fuster, V., Halperin, J. et al. Stroke risk assessment in atrial fibrillation: risk factors and markers of atrial myopathy. Nat Rev Cardiol 13, 549–559 (2016). https://doi.org/10.1038/nrcardio.2016.106
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DOI: https://doi.org/10.1038/nrcardio.2016.106
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