TIA work-up in ED

A transient ischemic attack portends significant risk of a stroke. Consequently, the diagnostic evaluation in the emergency department is focused on identifying high-risk causes so that preventive strategies can be implemented. The evaluation consists of a facilitated evaluation of the patient’s metabolic, cardiac, and neurovascular systems. At a minimum, the following tests are recommended: fingerstick glucose level, electrolyte levels, CBC count, urinalysis, and coagulation studies; noncontrast computed tomography (CT) of the head; electrocardiography; and continuous telemetry monitoring. Vascular imaging studies, such as carotid ultrasonography, CT angiography, or magnetic resonance angiography, should be performed on an urgent basis and prioritized according to the patient’s risk stratification for disease. Consideration should be given for echocardiography if no large vessel abnormality is identified.

KEY CONCEPTS

• The risk of stroke is greatest immediately after a transient ischemic attack; thus, a rapid evaluation to determine the cause of the event and potentially preventable risk factors is imperative.
• At a minimum, the ED evaluation of a transient ischemic attack should include noncontrast CT of the head, fingerstick glucose level, serum chemistry studies, CBC count, a coagulation profile, urinalysis, electrocardiography, and a pregnancy test when appropriate.
• The subsequent evaluation of a patient who has had a transient ischemic attack should focus on identifying highrisk causes and thus involve cardiac monitoring; vascular imaging such as carotid ultrasonography, computed tomographic angiography, or magnetic resonance angiography; and echocardiography if the previous evaluation result is negative or if there is a potential high-risk cardiac source.
• Carotid duplex ultrasonography is excellent for identifying internal carotid artery stenosis as a cause of a transient ischemic attack; however, it visualizes only a short segment of the carotid artery and is relatively insensitive for dissection.
• If cervicocephalic arterial dissection is suspected, MRI with axial fat-saturated T1 images or computed tomographic angiography should be ordered.

Ann Emerg Med. 2008;52:S17-S26.