For patients arriving at emergency departments with chest pain, the difference between unnecessary hospitalization and a missed heart attack often hinges on imaging precision. Coronary computed tomography angiography (CCTA) is reshaping that calculus — not just by detecting blockages, but by characterizing the biological danger of plaque itself, a distinction that could redefine how acute coronary syndrome (ACS) is triaged and managed.

This review, published in Current Problems in Cardiology, synthesizes trial evidence on CCTA's diagnostic and prognostic performance across the ACS spectrum. In low-risk chest pain presentations, randomized trial data confirm CCTA enables safe early discharge and meaningfully shortens hospital stays. That benefit diminishes, however, in intermediate- and high-risk patients, where CCTA demonstrated adequate diagnostic accuracy but failed to improve clinical outcomes, reduce resource use, or prove cost-effective relative to contemporary standard care. The review's more provocative contribution involves CCTA-derived high-risk plaque features — specifically positive remodeling, low-attenuation plaque, spotty calcifications, and the napkin-ring sign — each of which adds prognostic signal beyond conventional stenosis grading and established cardiovascular risk scores.

These plaque morphology markers matter because traditional angiography measures luminal narrowing, not plaque vulnerability. A 40% stenosis harboring low-attenuation lipid-rich necrotic core may carry greater rupture risk than a 70% calcified, stable lesion. This qualitative distinction has been recognized in intravascular imaging literature for over a decade, but CCTA's non-invasive delivery of comparable characterization represents a meaningful clinical advance — if it can be standardized reliably across scanner platforms and reading protocols. The review's honest acknowledgment that intermediate- and high-risk populations see limited outcome benefit is a necessary corrective to enthusiasm that sometimes outpaces evidence. CCTA's real-world value in ACS likely depends on precise patient stratification upfront, with the highest yield in chest pain units deploying structured low-risk pathways. The integration of emerging CT-based technologies — fractional flow reserve derived from CT, pericoronary fat attenuation, and AI-assisted plaque quantification — may eventually extend the modality's utility into higher-risk tiers, but robust outcome data for those tools remain early-stage.