Yield of diagnostic tests in evaluating syncopal episodes in older patients

Syncopal episodes are common among older adults; etiologies range from benign to life threatening. We determined the frequency, yield, and costs of tests obtained to evaluate older persons with syncope. We also calculated the cost per test yield and determined whether the San Francisco syncope rule (SFSR) improved test yield.

Review of 2106 consecutive patients 65 years or older admitted following a syncopal episode.

Electrocardiograms (in 99% of admissions), telemetry (in 95%), cardiac enzyme tests (in 95%), and head computed tomographic (CT) scans (in 63%) were the most frequently obtained tests. Results from cardiac enzymes tests, CT scans, echocardiography, carotid ultrasonography, and electroencephalography all affected diagnosis or management in less than 5% of cases and helped determine the etiology of syncope less than 2% of the time. Postural blood pressure (BP) recording, performed in only 38% of episodes, had the highest yield with respect to affecting diagnosis (18%-26%) or management (25%-30%) and determining etiology of the syncopal episode (15%-21%). The cost per test affecting diagnosis or management was highest for electroencephalography ($32 973), CT scans ($24 881), and cardiac enzymes test ($22 397) and lowest for postural BP recording ($17-$20). The yields and costs for cardiac tests were better among patients meeting, vs those not meeting, the SFSR. For example, the cost per cardiac enzymes test affecting diagnosis or management was $10 331 in those meeting, vs $111 518 in those not meeting, the SFSR.

Many unnecessary tests are obtained to evaluate syncope. Selecting tests based on history and examination and prioritizing less expensive and higher yield tests would ensure a more informed and cost-effective approach to evaluating older patients with syncope.