Objectives To evaluate a new 3D MRI protocol for the reliable detection of aortic high-risk plaques compared to transesophageal echocardiography (TEE) and to test the reliability of additional MRI in stroke of undetermined etiology.
Methods 74 acute stroke patients were examined by both TEE and MRI at 3Tesla with special regard to aortic high-risk plaques (i.e., ≥4 mm, superimposed thrombi). ECG synchronized pre- and post-contrast T1-weighted 3D imaging (spatial resolution ~1mm3) covering the thoracic aorta was employed. In plaques ≥3 mm, additional 2D T2 imaging and time-resolved (CINE) imaging sequences were performed. Etiology of brain ischemia was classified according to modified TOAST criteria. Aortic high-risk embolic sources detected by MRI in patients with cryptogenic stroke were evaluated.
Results Differences in maximum aortic wall thickness (AWT) for TEE and MRI were not statistically significant for all aortic segments. The overall number of high-risk plaques detected by MRI (n=74) was substantially higher compared to TEE (n=47). Most noticeably, MRI identified aortic high-risk pathologies in 8/26 (30.8%) patients with cryptogenic stroke after standard diagnostics including TEE (n=2: dissection or thrombus; n=6: plaques ≥4 mm).
Conclusions Our results demonstrate the feasibility of this 3D MRI protocol for the reliable detection of aortic high-risk plaques in acute stroke patients. Due to the improved visualization of the aortic arch and the detection of additional embolic sources not seen by standard diagnostics this novel technique may become a valuable tool for future patients with cryptogenic stroke.
- Transesophageal echocardiography