Cryptogenic Stroke—The Appropriate Diagnostic Evaluation

Cerebrovascular Disease and Stroke (D Greer, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Cerebrovascular Disease and Stroke

Opinion statement

Ischemic strokes are a significant cause of morbidity and mortality in the United States. They may be due to large artery atherosclerosis, small vessel occlusion, cardioembolism, or other less common mechanisms such as toxins, hypercoagulable disorders, and vasospasm. Each mechanism carries its own risk of recurrence and prognosis. Strokes without an identifiable cause despite a complete work-up are described as cryptogenic. Cryptogenic stroke therefore is a diagnosis of exclusion, and one that should not be arrived at haphazardly. One must complete a thorough, and frequently challenging, stroke work-up prior to this diagnosis. Challenges in determining stroke etiology include the transient nature of precipitating events such as vasospasm or cardiac arrhythmias, variable durations of cardiac monitoring, and unclear significance of certain cardiac structural anomalies. Many consider cryptogenic stroke to be a heterogeneous combination of paroxysmal and occult conditions that create such diagnostic difficulties. The diagnosis of cryptogenic stroke itself carries with it specific outcomes and prognosis. This article will provide an overview of the definition and epidemiology, recommendations for diagnostic evaluation, and risks of recurrence of cryptogenic stroke.

Keywords

Cryptogenic stroke Cardioembolism Atrial fibrillation Large vessel Small vessel disease Hypercoagulable Patent foramen ovale Cardiac monitoring 

Notes

Compliance with Ethics Guidelines

Conflict of Interest

Dr. Hardik Amin declares that he has no conflicts of interest.

Dr. David M. Greer serves as a Section Editor for Current Treatment Options in Cardiovascular Medicine.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.

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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Yale New Haven Hospital, LCI BuildingNew HavenUSA

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