Diagnostic yield and utility of neurovascular ultrasonography in the evaluation of patients with syncope

Abstract

Objective: To determine the diagnostic utility of neurovascular ultrasonography (transcranial Doppler and carotid ultrasonography) in patients with syncope.

Patients and methods: We retrospectively identified consecutive patients who underwent neurovascular ultrasonography for the diagnosis of syncope or presyncope at an academic hospital in 1997 and 1998. From medical records we abstracted patient demographic and clinical information, results and consequences of testing, and follow-up data for 3 years.

Results: A total of 140 patients participated in the study. The median age of the study patients was 74 years (interquartile range, 66-80 years), and 49% were male. Severe extracranial or Intracranial cerebrovascular disease was found on neurovascular ultrasonography in 20 patients (14%; 95% confidence interval [CI], 9.5%-21%). Focal neurologic signs or symptoms or carotid bruits were found in 19 (95%) of 20 patients with positive test results compared with 46 (38%) of 120 patients without severe disease (P<.001). Ultrasonography identified cerebrovascular lesions that may have contributed to the syncopal process in only 2 (1.4%) of 140 patients (95% CI, 0.39%-5.1%), but the lesions were unlikely to have been the primary cause of syncope in either patient.

Conclusion: In this predominantly stroke-age population, neurovascular ultrasonography had a low yield for diagnosing vascular lesions that contributed to the pathophysiology of syncope. However, in patients with focal signs or symptoms or carotid bruits, it detected incidental lesions that typically require treatment or follow-up. In patients with syncope, neurovascular ultrasonography should be reserved for this subset. The data suggest enhancements to the American College of Physicians guideline for the use of neurovascular ultrasonography in patients with syncope.