The goal of this trial is to study, in three well-defined clinical situations responsible for cerebral hypoxia, the concentrations of biomarkers of thrombo-inflammation compared to a population of patients without cerebral hypoxia, and to study in patients with cerebral hypoxia the association between these concentrations and the clinical evolution.

Inclusion Criteria:

- For cases, admitted within the first 36 hours of an acute neurological symptom related to :

• An ischaemic cerebrovascular accident (iCVA) eligible for a mechanical thrombectomy procedure,
• A subarachnoid haemorrhage (SAH, all aetiologies) : patient presenting with at least a modified Fisher scale 3 or 4,
• An intra-parenchymal haematoma (IPH) with greatest axis ≥ 20mm or with NIHSS on admission >4.

OR

• For control patients, admitted within 7 days of the onset of acute neurological symptomatology related to a clinical diagnosis of transient ischaemic attack (TIA) - based on thorough questioning of the patient on admission - and prior to imaging, with an ABCD2≥ 2 score.
• Express consent to participate in the study.
• Member or beneficiary of a social security.

Exclusion Criteria:

• Pre-existing functional and/or cognitive disability
• Patient under legal protection.
• Pregnant or breastfeeding woman.
• Patient with secondary haemorrhagic transformation.

Secondary exclusion criteria :

• Patients with an ischaemic lesion visible on imaging, unrelated to large vessel occlusion and therefore ineligible for mechanical thrombectomy.
• Patients diagnosed with an acute non-vascular neurological pathology (migraine, epilepsy, etc.).
• TIA patients presenting an abnormality on follow-up imaging 24-48 hours after the initial imaging.

Excluded patients will be replaced.

Patients treated at the Rothschild Foundation Hospital within the first 24 hours of an acute neurological symptomatology