Intra-Arterial Magnesium Therapy After Mechanical Thrombectomy in Acute Ischemic Stroke

Patients meeting inclusion and exclusion criteria will undergo a baseline neurologic assessment and will be enrolled following informed consent. The patient will then be taken to the Interventional Radiology suite where the patient will undergo MT as per the standard of care. Participation in this study will never delay the timely provision of urgent MT to patients. Additionally, as part of the study procedure, the patient will be assigned to Treatment Group 1,2, 3 or 4 based on the consecutive sampling scheme. The first 6 patients enrolled will be in group 1 and receive the lowest dose of MgSO4 as described below. If the analysis of this group deems this dosage to be safe, the following patients will be enrolled into group 2. The same scheme will be followed until all 4 groups are enrolled. Patients in all groups will receive IA MgSO4 as follows (investigational): Patients in each group will receive the specified dose of MgSO4 (listed below) diluted in 0.9% sodium chloride. The infusion of IA MgSO4 will be administered over 1-2 minutes. Dose Escalation Schedule Group 1 0.25g IA MgSO4 Group 2 0.5g IA MgSO4 Group 3 1g IA MgSO4 Group 4 1.5g IA MgSO4 Given the minimal safety data on IA MgSO4, this dosage regimen was derived from previous IV MgSO4 studies and a singular IA MgSO4 study in a separate population to cautiously investigate the safety and tolerability for IA MgSO4. Following MT and IA infusion, patients will receive a continuous infusion of IV MgSO4 for 24 hours. The maintenance infusion will contain 16g of MgSO4 diluted in 240 ml of 0.9% normal saline, infused at a rate of 10 ml per hour for 24 hours. Patients will follow the standard of care monitoring for post-MT patients with the addition of monitoring for magnesium toxicity. All pre and post imaging is standard of care for this procedure, including follow up MRI (or CT if MRI contraindicated). Following discharge from the hospital, all patients enrolled in the study protocol will be followed up in the clinic at 3 months to evaluate the patient's functional clinical outcome. If for any reason, the patient cannot come back for a follow-up visit, the PI/Co-PI's will contact the patient via phone/email to gather the required data. A minimum of mRS and NIHSS should be gathered for follow-up data.