Coronary CT angiography in acute coronary syndromes: a contemporary real-world experience

Background Coronary computed tomography angiography (CCTA) has emerged as a non-invasive imaging modality for evaluating suspected acute coronary syndromes (ACS). CCTA, owing to its high negative predictive value, allows reliable exclusion of coronary artery disease (CAD) and provides detailed anatomical information on plaque presence, burden, and morphology. Beyond excluding obstructive disease, CCTA offers insights not routinely obtained from Invasive Coronary Angiography (ICA), including improved assessment of total plaque burden and identification of high-risk plaque features. Several studies have demonstrated that CCTA can effectively reduce unnecessary ICAs while ensuring patient safety. However, its role in patients presenting with non-ST-elevation ACS (NSTE-ACS) without high-risk features remains undefined. The purpose of this study is to assess the diagnostic yield and clinical impact of a CCTA-first strategy in low- and intermediate-risk patients presenting with NSTE-ACS. Methods We analyzed 1,001 consecutive patients ≥18 years presenting to the emergency department with NSTE-ACS who did not meet high-risk criteria (hemodynamic instability, dynamic ST-T changes, ventricular arrhythmias, GRACE score >140, refractory angina, heart failure, or cardiorespiratory arrest). They underwent CCTA as the initial coronary imaging modality. Data collection was carried out between May 11, 2022 and February 20, 2026. Results 1001 patients were included, with a mean age of 57 years, of which 44% were women and 56% men. Among the admission diagnoses, 21% were NSTEMI and 79% were unstable angina according to the 4th universal definition of acute myocardial infarction (AMI). The median high-sensitivity cardiac troponin T value was 6 nanograms per litre (interquartile range, 4 to 13) for the first troponin sample, and 9 nanograms per litre (interquartile range, 6 to 22) for the second sample. CCTA was not performed in 7% due to a CAC score >400 AU. Among patients who underwent CCTA, 27% had no coronary plaques and 40% had non-obstructive coronary artery disease (<50% stenosis), while 25% had obstructive disease and 8% had nondiagnostic studies. High-risk plaque features were identified in 13%. Invasive coronary angiography was performed in 36% of patients, with coronary revascularization required in 23%. Conclusion In this large real-world cohort of low- and intermediate-risk NSTE-ACS, two-thirds of patients had no obstructive coronary disease on CCTA. A CCTA-first strategy may safely reduce invasive angiography while improving detection and characterization of non-obstructive coronary artery disease, supporting its integration into the diagnostic algorithm of selected ACS patients. Furthermore, the identification of nonobstructive CAD in 40% of our patients underscores a critical window to guide initiation or optimization of preventive medical therapy.Table 1CCTA findings