The use of diagnostic tests in patients with acute ischemic stroke

Stroke is a leading cause of long-term disability in the United States. Inpatient hospital costs account for the majority of acute care costs of stroke with half the cost providing for room and board and 19% of total costs allocated to diagnostic testing. This study addresses the yield of common diagnostic tests in stroke and how frequently the results potentially impact early stroke management.

We conducted a retrospective chart review of patients with acute ischemic stroke over 3 years from a single-center community-based teaching hospital. Results of carotid Doppler (CD), transcranial Doppler, extracranial magnetic resonance (MR) angiography (EMRA), intracranial MR angiography, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), and 24-hour Holter monitoring were reviewed.

Extracranial carotid artery imaging with CD and EMRA showed symptomatic ipsilateral stenosis in 7.9% and 13% of patients with stroke. TTE alone showed intracardiac thrombus in 1.5% of patients whereas TEE had a yield of 3.8%. Patent foramen ovale was seen in 16% of TEE and none were detected on TTE. The 24-hour Holter monitoring revealed newly detected atrial fibrillation in 9.4% of patients with stroke.

Standard diagnostic studies in acute stroke aimed at secondary stroke prevention are unlikely to yield results that warrant prolongation of hospitalization. Carotid endarterectomy is the only intervention with reasonable evidence suggesting benefit in the early period after stroke. Pursuing extracranial carotid artery imaging during initial hospitalization seems justifiable, especially given the high yield of CD and EMRA in the detection of treatable carotid artery stenosis.