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Atrial fibrillation: Risk of embolization

Authors
Warren J Manning, MD
Daniel E Singer, MD
Section Editors
Peter J Zimetbaum, MD
Scott E Kasner, MD
Deputy Editor
Gordon M Saperia, MD, FACC

INTRODUCTION

The most serious common complication of atrial fibrillation (AF) is arterial thromboembolism; the most clinically evident thromboembolic event is ischemic stroke. (See "Initial assessment and management of acute stroke" and "Pathophysiology of ischemic stroke".)

Peripheral embolization accounts for less than 10 percent of all such events and many of these are subclinical [1-3]. Knowledge of the risk of stroke (and peripheral embolization) is important for two reasons: to help the patient better understand their disease (AF) and its natural history; and, more importantly, to help determine which patients might benefit from attempts to prevent thromboembolism.

Antithrombotic therapy with oral anticoagulant has been shown to lower the risk of clinical thromboembolism in virtually all patients with AF, including all levels of risk and irrespective of type (paroxysmal, persistent, or permanent). (See "Overview of atrial fibrillation", section on 'General classification'.)

However, in the lowest-risk patients, the risk of anticoagulant-related major bleeding may equal or exceed the risk of clinical thromboembolism without anticoagulant therapy. Thus, for these lowest-risk patients, clinicians need guidance regarding when to recommend such therapy. Risk prediction models have been developed for this purpose, although each has significant limitations. We prefer the CHA2DS2-VASc model and will focus on it in this topic. (See 'Options for estimating risk in the individual patient' below.)

The individual predictors and the models used to predict embolic risk in patients with nonvalvular AF are discussed in this topic. The way in which the risk models are used in clinical decision making regarding antithrombotic therapy is discussed separately. (See "Atrial fibrillation: Anticoagulant therapy to prevent embolization", section on 'Clinical use of anticoagulants'.)

                    

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Literature review current through: Nov 2016. | This topic last updated: Tue Aug 30 00:00:00 GMT 2016.
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