Cordato, Dennis

BACKGROUND: Cardiac computed tomography (CT) acquired during the acute stroke imaging protocol is an emerging modality to detect cardiac thrombi. We determined its yield in patients with acute ischemic stroke. METHODS: We performed a 1-stage individual patient data meta-analysis of 4 prospective observational cohorts (AIS of HEARTS [Acute Ischemic Stroke of Heart-Related Embolic Sources Detected on Acute Cardiac CT Scans]), including patients with acute ischemic stroke who underwent ECG-gated or non–ECG-gated cardiac CT between May 2018 and June 2024. We excluded patients with transient ischemic attack or stroke mimics. The primary outcome was the proportion of patients with a thrombus on cardiac CT. Secondary outcomes were additional scan time, radiation dose, comparison with echocardiography, and 90-day outcomes. We performed logistic regression analyses to compare 90-day outcomes between patients with and without thrombus, adjusting for age, sex, history of atrial fibrillation, ischemic heart disease, chronic heart failure, stroke or transient ischemic attack, anticoagulant use, prestroke modified Rankin Scale score, National Institutes of Health Stroke Scale score, large vessel occlusions, and intravenous thrombolysis, as appropriate for each outcome. RESULTS: We included 3919 patients (median age, 74 [interquartile range (IQR), 63–82], 58% male, median National Institutes of Health Stroke Scale score 6 [IQR, 3–12]). Cardiac CT detected a thrombus in 243 (6.2%) patients. Among 1323 patients that underwent both cardiac CT and transthoracic echocardiography, cardiac CT had a higher yield than transthoracic echocardiography (odds ratio, 7.4 [95% CI, 4.0–15.1]; P <0.001). Median additional scan time was 6 minutes (IQR, 5–7) for ECG-gated and 13 seconds (IQR, 12–61) for non–ECG-gated cardiac CT. Median additional radiation dose was 2.9 mSv (IQR, 1.6–4.1). Patients with thrombi had higher 90-day mortality (33% versus 15%, adjusted odds ratio, 1.6 [95% CI, 1.1–2.3]) and worse modified Rankin Scale scores (median modified Rankin Scale score 3 versus 2, adjusted odds ratio, 1.6 [95% CI, 1.2–2.0]), but similar recurrent stroke rates (5% versus 4%, adjusted odds ratio, 1.4 [95% CI, 0.7–2.5]). CONCLUSIONS: Implementing cardiac CT into the acute stroke imaging protocol is feasible, detects thrombi in ≈6% of patients, and has a higher yield than transthoracic echocardiography. Cardiac thrombi were associated with higher mortality, but not higher stroke recurrence. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT07165093.

Background Large vessel occlusion (LVO) stroke is associated with a high risk of permanent disability. There are no reliable tools providing periprocedural information on clot characteristics, such as composition and length, that may impact first pass effect, which has been shown to improve functional outcomes. In the first study of a novel technology, we evaluated whether the Clotild Smart Guidewire System (Clotild), an impedance-based device, can provide in situ information on clot characteristics during a mechanical thrombectomy procedure. Methods This is the first-in-human, international, multicentric, single-arm trial involving LVO stroke patients. Of 45 enrolled subjects, 41 constituted the safety population; 39 was the per protocol population, of which 26 subjects with complete impedance data comprised the performance population. The latter was divided into development (11 subjects) and validation (15 subjects) populations for prediction model development and assessment. The safety endpoint assessed Clotild-related intracranial vessel perforation/dissection. Performance endpoints evaluated Clotild’s ability to perform classification of impedance measurements distinguishing substantial versus negligible local content in red blood cells (RBCs) and platelets, to detect the arterial wall and the distal end of the clot. Results The safety endpoint was met in all subjects. Performance analysis comparing the agreement between Clotild’s output and impedance experts’ readings showed an area under the receiver operating characteristic curve (AUC) of 0.97 (95% CI 0.93 to 0.99) for RBC, and 0.94 (95% CI 0.89 to 0.98) for platelet clot composition. Regarding detection, Clotild’s performance showed an AUC of 0.69 (95% CI 0.59 to 0.77) for the arterial wall, and 0.83 (95% CI 0.59 to 1.00) for the distal end of the clot. Conclusions Clotild was proven safe to acquire impedance data and to provide information on in situ clot characteristics in large vessel occlusions.

Background: Cardiac CT acquired during the acute stroke imaging protocol is an emerging diagnostic modality to detect cardiac thrombi. We aimed to determine its diagnostic yield in a large, international, multicenter study. Methods: We performed an individual patient data meta-analysis by pooling prospective and retrospective observational data of patients with acute ischemic stroke (AIS) who underwent cardiac CT (ECG-gated or non-ECG-gated) as part of the acute imaging protocol between May 2018 and June 2024. We excluded patients with a TIA or stroke mimic. The primary outcome was the proportion of patients with a cardiac thrombus detected on cardiac CT. Secondary outcomes were additional scan time and radiation dose, comparison of yield with echocardiography, and 90-day mortality and recurrent ischemic stroke rates. Results: We included 3940 patients from 4 hospitals (median age 74 [IQR 63-82], 58.0% male, median NIHSS 6 [IQR 3-12], median time onset to hospital arrival 100 minutes [IQR 62-185]). Atrial fibrillation at baseline was present in 23.1% patients, and 29.6% had a large vessel occlusion. Cardiac CT was non-diagnostic in 17 (0.4%) patients. In total, cardiac CT detected 254 cardiac thrombi in 243/3923 (6.2%) patients. Thrombi were located in the left atrial appendage (n=193), left atrium (n=19), and left ventricle (n=42). Of 95/243 (39.1%) patients with a cardiac thrombus that underwent echocardiography (median interval cardiac CT-echocardiography: 2 days), transthoracic echocardiography detected a thrombus in 18/92 (19.6%) patients and transesophageal echocardiography in 2/5 (40.0%) patients. The diagnostic yield in patients that underwent both modalities was higher for cardiac CT (OR 7.5 [CI 4.0-15.3], p<0.001). Median additional scan time was 6 minutes (IQR 5-7) for ECG-gated and 17 seconds (IQR 15-63) for non-ECG-gated cardiac CT. Median additional radiation dose was 5.4mSv (IQR 3.0-7.6). Patients with a cardiac thrombus on cardiac CT had higher 90-day mortality than those without a thrombus (33.3% vs 14.6%, p<0.001). We found no difference in 90-day recurrent stroke rate (5.4% vs 4.4%, p=0.50). Conclusion: Routine cardiac CT performed during the acute stroke imaging protocol detects a cardiac thrombus in 1 out of 16 patients with AIS, with a 7-times higher yield than routine echocardiography. Mortality rate was doubled in patients with a cardiac thrombus, but 90-day stroke recurrence risk did not differ.

Background: The rate of intracardiac thrombus detection in the hyperacute phase of stroke varies from 5% to 12% between studies. Our aim was to compare the thrombus detection rate between ECG-gated and non-ECG-gated cardiac CT protocols in acute stroke patients, using data from a large, international, multicentre registry. Methods: We conducted an individual patient data meta-analysis by pooling prospective and retrospective observational data from stroke patients assessed at four comprehensive stroke centres who underwent either ECG-gated or non-ECG-gated cardiac CT (extended CT angiography or two-phase non-ECG-gated cardiac CT) as part of the acute stroke imaging protocol between May 2018 and June 2024. The primary outcome was the proportion of patients with a cardiac thrombus in gated vs non gated techniques. Results: Of 3,940 patients, 1,474 (37.4%) underwent ECG-gated and 2,466 (62.6%) non-ECG-gated cardiac CT. Patients in the ECG-gated group were younger (median age 72 [IQR 62–81] vs. 74 [IQR 64–82] years, p = 0.000) and had a lower NIHSS at baseline (median 5 [IQR 2–12] vs. 6 [IQR 3–13], p < 0.00). There was a higher rate of thrombus detection with ECG-gated CT compared to non-gated CT (7.5% vs. 5.5%, p = 0.011. The association remained significant after adjusting for age, sex, baseline NIHSS score, and baseline atrial fibrillation (adjusted OR 1.87, 95% CI 1.42–2.47, p = 0.000). ECG-gated CT was associated with lower radiation dose (3.6 vs. 6.3 mSv, p = 0.000) but longer acquisition time (5.8 vs. 0.28 min, p = 0.000). Conclusion: ECG-gated cardiac CT has a higher detection rate for intracardiac thrombus detection compared to non-ECG-gated CT in patients with acute ischemic stroke.

Background Rapid stroke type identification is essential for time‐sensitive interventions, yet timely neuroimaging remains limited, especially in pre‐hospital and resource‐constrained settings. The EMVision emu™ Brain Scanner is a portable neurodiagnostic device using non‐ionizing electromagnetic signals to distinguish stroke subtypes. In an Australian prevalidation study enrolling 277 suspected stroke patients, it demonstrated diagnostic accuracy with sensitivity and specificity of 92% and 85% for hemorrhagic and 95% and 80% for ischemic strokes, respectively. Case studies and image reconstructions provided (figures 1 and 2). This follow‐up study aims to validate the diagnostic performance of emu™ for detecting intracranial hemorrhage in an international cohort, targeting ≥80% sensitivity and specificity. Methods A prospective, multi‐center, international, paired diagnostic accuracy study, with 4 US sites and 2 Australian sites. It will enroll 300 patients presenting within 12 hours of stroke onset. Patients will be stratified into two arms: intracranial hemorrhage, and ischemic stroke, TIA, or stroke mimic. Participants will undergo standard imaging, followed by non‐invasive scan by the emu™ device. Ground‐truth diagnoses will be adjudicated by a blinded expert panel. The primary endpoints are the sensitivity and specificity of the emu™ device for detecting hemorrhage, calculated against the reference standard. Statistical inference will rely on whether the lower bound of the 95% confidence interval for sensitivity and specificity exceeds 80%. Results First Australian and US enrollments occurred on June 11, 2025, and July 3, 2025, respectively. Latest progress in the study will be presented at the time of conference. Conclusion This is the first international validation study of a portable electromagnetic brain scanner for intracranial hemorrhage detection; a novel, non‐ionizing, diagnostic tool that can revolutionize acute stroke triage, enabling earlier treatment decisions, improved workflows, and equitable access to neuroimaging. image image