DSA Versus Noninvasive Imaging in Revascularization Referral for Recently Symptomatic Carotid Stenosis

Current revascularization guidelines for symptomatic carotid artery stenosis were established based on randomized studies where stenosis was assessed with digital subtraction angiography. Pursuing revascularization in clinical practice is typically based on noninvasive imaging. We aimed to assess whether discrepancies exist between these 2 diagnostic methods when patients with recently symptomatic carotid stenosis referred for carotid revascularization based on noninvasive imaging, subsequently underwent DSA.

A retrospective study of patients presenting at 3 centers in the United States and Türkiye who routinely performed digitally subtracted angiography prior to revascularization between 2019 and 2024 was performed. Consecutive patients with acute ischemic events and concern for symptomatic ipsilateral carotid artery stenosis with moderate to severe stenosis on noninvasive imaging referred for digitally subtracted angiography were selected for inclusion. Digitally subtracted angiography was performed for intended carotid artery stenting in most cases as the first-line treatment method; patients referred for carotid endarterectomy who underwent preprocedure digitally subtracted angiography were also included. Exclusion criteria included prior carotid endarterectomy or carotid artery stenting or the presence of intraluminal thrombus precluding immediate revascularization. The primary outcome was the rate of disagreement between noninvasive imaging and digitally subtracted angiography.

A total of 463 patients (65% males) were included, with a median age of 69 years. Disagreement regarding qualifying lesion severity for revascularization between noninvasive imaging and digitally subtracted angiography was found in 22.7% of patients. There was a significant difference in the proportion of immediate revascularization between the 2 cohorts (P<0.001). A total of 66/105 (63%) of those in the disagreement cohort were determined to have an etiology of stroke alternative to large artery atherosclerosis, requiring further diagnostic evaluation.

This study demonstrates that almost 1 in 4 patients referred for carotid revascularization based on noninvasive imaging are found to have insufficient stenosis on digitally subtracted angiography to support the decision to proceed with revascularization according to established stenosis severity thresholds.