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 myocardial infarction (\< 4 weeks), left ventricular ejection fraction (EF) \< 30%, valve vegetations or infective endocarditis. * No other identified cause of stroke (such as arteritis, dissection, migraine, vasospasm, drug abuse, hypercoagulability, etc.) Presence of LVD defined by at least one of the following criteria: * Moderately reduced left ventricular (LV) systolic function, defined as EF 30-49%. * LV wall motion abnormalities (LVWMAs), defined as hypokinetic, akinetic, or dyskinetic segments of the left ventricular wall not associated with recent or acute myocardial infarction (within 4 weeks). * LV aneurysm * Enlarged LV with or without spontaneous contrast * Non-compacted LV, with deep trabeculations or spongy LV * Cardiomyopathies, such as restrictive cardiomyopathy, hypertrophic cardiomyopathy, or cardiac amyloidosis Patients capable of signing informed consent (IC) or, in the case of unconscious patients without an authorized legal representative, recruited in a "Deferred" mode Exclusion Criteria: * Major cardioembolic sources, as specified in the ESUS criteria Patients with a thrombophilic state secondary to active cancer, defined as "diagnosis of solid or hematologic malignant tumor within 6 months of stroke, ongoing oncological treatment, or hematologic cancer not in remission." Patients with ipsilateral carotid plaques to the ischemic stroke considered at high risk: thrombus on the wall, floating thrombus, ulcerated plaque. Patients under 60 years of age with a high-risk patent foramen ovale (PFO) and stroke classified as "probable" PFO-associated stroke according to the PASCAL classification. Pregnancy or puerperium. Contraindication to MRI and CT with contrast agents