Cardiac Assessment for Thrombus Detection in the Heart Using Advanced Imaging (MRI, CT) in ESUS With Left Ventricular Disease

Inclusion Criteria: * Age between 18 and 85 years Modified Rankin Scale (mRS) score ≤ 4 Diagnosis of acute ischemic stroke (detected by CT or brain MRI) Diagnosis of ESUS according to standard criteria * Stroke detected by CT or MRI that is not lacunar. Lacunar is defined as a subcortical infarction (including pons and mesencephalon) in the distribution of the small penetrating cerebral arteries, with a maximum size ≤ 1.5 cm on CT or ≤ 2.0 cm on diffusion-weighted MRI images (\< 1.5 cm on T2-weighted MRI images). Excluded: multiple small deep infarcts, lateral bulb infarcts, cerebellar infarcts, patients with clinical lacunar stroke syndrome and no visible infarction on imaging. * Absence of extracranial or intracranial atherosclerosis causing ≥ 50% stenosis in the artery supplying the ischemic area. Vascular imaging of the extracranial and intracranial vessels is required using angiography, CT angiography (CTA), MR angiography (MRA), or color Doppler ultrasound, at the discretion of the treating physician and local principal investigator. * No major cardioembolic source identified, including permanent or paroxysmal atrial fibrillation (AF), sustained atrial flutter, intracardiac thrombus (\*as specified above, these patients will be recruited in phase 1 of the study only if an isolated ventricular thrombus is found without other major cardiac causes), mechanical heart valve prosthesis, atrial myxoma or other cardiac tumors, moderate or severe mitral stenosis, recent myocard…