Lancet Neurol. 2025 Jun;24(6):489-499. doi: 10.1016/S1474-4422(25)00111-5.
ABSTRACT
BACKGROUND: Cardioembolic sources often remain undetected after standard diagnostic stroke workup, contributing to high rates of recurrence. We aimed to assess whether a head-to-neck CT angiography extended at least 6 cm below the carina (extended CT angiography) can increase the detection of cardioaortic thrombi compared with standard-of-care CT angiography (standard CT angiography) in patients with ischaemic stroke or transient ischaemic attack.
METHODS: This single-centre, prospective, randomised, open-label, blinded end-point trial was done at London Health Sciences Centre, Western University, Canada. Eligible patients were adults aged 18 years or older with ischaemic stroke or transient ischaemic attack assessed during acute code strokes. Exclusion criteria were known allergy or concerns about the safety of iodinated contrast agents (eg, severe renal failure) and no intravenous access. Participants were randomly assigned in a 1:1 ratio to receive standard CT angiography or extended CT angiography. Patients, neurologists adjudicating qualifying events, cardiothoracic radiologists, and cardiologists adjudicating study outcomes were masked to randomisation. Adjudicators were considered masked to randomisation as they did not know which patients were crossovers, which patients in the standard of care arm had partial imaging of the left atrial appendage due to normal variations in size and shape, and which patients in the extended CT angiography group also had partial imaging of the left atrial appendage instead of full imaging. The primary efficacy outcome was the detection of a cardioaortic thrombus (modified intention-to-treat population). The primary safety outcome was time to CT angiography completion (as-treated population). The trial was registered at ClinicalTrials.gov, NCT05522244, and is closed.
FINDINGS: Between July 17, 2023, and May 6, 2024, 963 patients were assessed for inclusion. 133 were excluded because they already had a CT angiography at their local hospital, intracranial haemorrhage was identified on the initial non-contrast CT, a diagnosis of stroke was considered highly unlikely by the treating stroke neurologist, or randomisation was not possible. 830 patients were enrolled and randomly assigned to extended CT angiography (n=415) or standard CT angiography (n=415). One patient withdrew consent and was excluded from the analyses. 364 participants who were later adjudicated as having experienced stroke mimics were excluded. 465 patients with ischaemic stroke or transient ischaemic attack were included in the modified intention-to-treat population (226 in the extended CT angiography group and 239 in the standard CT angiography group). 239 (51%) of 465 patients were female and 226 (49%) were male. Median age of the analysis group at enrolment was 78·0 years (IQR 69·0-84·0). The primary outcome (cardioaortic thrombus) was detected in 20 (8·8%) of 226 patients in the extended CT angiography group and four (1·7%) of 239 in the standard CT angiography group (odds ratio 5·70, 95% CI 1·92-16·96; p=0·002). There were no statistically significant differences in the median time from code stroke activation to CT angiography completion between the extended CT angiography group (21·0 min; IQR 15·8-27·0 min) and the standard CT angiography group (20·0 min, 17·0-26·0 min). The median difference between extended CT angiography and standard CT angiography groups was 1·0 min (-1·0 to 2·5), p=0·67).
INTERPRETATION: Performing extended CT angiography during acute code strokes is feasible and results in increased cardioaortic thrombi detection without causing delays in CT angiography completion. Future studies should assess whether extended CT angiography can reduce recurrent stroke risk by prompting early anticoagulation after thrombus detection.
FUNDING: Western University, and the Kathleen and Dr Henry Barnett Chair in Stroke Research.
PMID:40409313 | DOI:10.1016/S1474-4422(25)00111-5
