ABSTRACT NUMBER: ESOC2026A1288 DETECTION OF CARDIAC SOURCES OF EMBOLI USING CARDIAC CT ANGIOGRAPHY IN HYPERACUTE STROKE IMAGING: A SINGLE-CENTRE RETROSPECTIVE COHORT STUDY OF REAL-WORLD EXPERIENCE

Abstract Background and aims Cardiac CT angiography (cCTA) is an emerging alternative imaging modality to examine cardiac structures during hyperacute stroke. Our centre is the first in Canada to incorporate cCTA (non-ECG-gated study) into routine clinical care. We aimed to measure its detection rate of cardiac sources of emboli, and its effects on management in this real-world population. Methods In this single-centre retrospective cohort study, modified Code Stroke imaging was implemented with a 64-slice CT scanner, where the longitudinal axis of CTA was extended to the diaphragm. cCTA findings were reported within 48h by cardiothoracic radiologists. Primary outcome of sources of cardiac embolism and secondary outcome of etiological reclassification and impact on patient management were assessed. Results During a 12-month period (2023-2024), there were 730 Code Stroke activations. Of 253 patients with ischemic stroke (50.6% female; average age 72.8 years), 28 (11.0%) had cCTA findings suggestive of cardiac emboli. Of these, one was a false positive on confirmatory testing. The remainder included: 10/27 patients with breakthrough stroke, 7/27 with new AF, 5/27 with left atrial appendage thrombus without AF, 2/27 with ventricular thrombus,1/27 with takotsubo cardiomyopathy and 1/27 with infective endocarditis. cCTA changed etiological reclassification in 11/253 (4.3%) and clinical management in 23/253 (9.1%) of patients. Conclusions Non-ECG gated cCTA is a reliable screening test for the detection of cardiac sources of emboli in hyperacute stroke patients. Known/new AF is the most common predictor of positive test. cCTA incorporation leads to etiological reclassification in 4% and changes clinical management in 9% of patients. Conflict of interest Abdullah Al-Subhi, Jack Lott, Domonique DaBreo, Gurmohan Rob Dhillon, Shirin Jalini,: all have nothing to disclose