# Cardiac CT in Large Vessel Occlusion Stroke for the Evaluation of Non-Thrombotic and Non-Atrial-Fibrillation-Related Embolic Causes

## TL;DR

This study shows that specific cardiac CT findings can help identify non-thrombotic and non-AF-related causes of stroke in patients with large vessel occlusion.

## Contribution

The study identifies novel cardiac CT imaging markers associated with cardioembolic stroke in patients without atrial fibrillation or intracardiac thrombi.

## Key findings

- Left ventricular dilation, interatrial shunts, and valve implants are strongly linked to cardioembolic stroke.
- Advanced aortic arch atheroma and post-ischaemic myocardial scars also increase cardioembolic risk.
- A combined model of these findings achieved an 83% accuracy in predicting cardioembolic stroke.

## Abstract

Background: The purpose of this study is the evaluation of imaging findings of acute-phase cardiac CT (cCT) in stroke patients with large vessel occlusion (LVO) to identify potential cardioembolic sources (CES) in patients without intracardiac thrombi and atrial fibrillation (AF). Material and Methods: This retrospective study included 315 patients with LVO who underwent cCT imaging in the acute stroke setting. The images were analysed for 15 imaging findings following the established minor and major cardioembolic risk factors. The final stroke aetiology was determined using the TOAST classification through interdisciplinary consensus following a thorough clinical evaluation. Multivariate regression analysis was performed to identify imaging findings associated with CES. Results: A cardioembolic aetiology was identified on cardiac CT in 211 cases (70%). After adjustment for AF and intracardiac thrombi, the multivariate regression analysis revealed significant associations with left ventricular dilation (adjusted odds-ratio (AOR) 32.4; 95% CI 3.0–349; p = 0.004), visible interatrial right-to-left shunt (AOR 30.8; 95% CI 2.7–341.3; p = 0.006), valve implants (AOR 24.5; 95% CI 2.2–270.9; p = 0.009), aortic arch atheroma grade > II (AOR 6.9; 95% CI 1.5–32.8; p = 0.015) and post-ischaemic myocardial scars (AOR 6.3, 95% CI 1.2–34.1; p = 0.032) as independent risk factors for a cardioembolic aetiology. The combined model achieved an area under the ROC curve of 0.83. Conclusions: In patients with LVO without AF and intracardiac thrombi as a cause, the presence of left ventricular dilatation, interatrial right-to-left shunts, valve implants, post-ischaemic myocardial scarring and advanced aortic arch atheroma (grade > 2) in particular is significantly associated with a cardioembolic cause of stroke and should be add-on evaluated in acute-phase cCT. Further investigations are warranted to confirm these associations.