Emergency Extracranial-Intracranial Bypass to Revascularize Salvageable Brain Tissue in Acute Ischemic Stroke Patients

Objective To present an algorithm based on clinical and radiologic factors, including magnetic resonance imaging (MRI) perfusion/diffusion mismatch (PDM), for the indication of urgent cerebral bypass in patients with acute ischemic stroke. Methods Clinical and radiologic data of 8 consecutive patients undergoing urgent cerebral revascularization for acute ischemic stroke owing to occlusion of internal carotid or middle cerebral artery between 2012 and 2015 were analyzed. All patients either were ineligible for or failed first-line treatment with emergent endovascular revascularization. Indication for urgent bypass was based on clinical worsening and MRI PDM, indicating threat for stroke extension. Clinical outcome was measured using National Institutes of Health Stroke Scale and modified Rankin Scale before and after bypass surgery, at 3-month follow-up, and at last follow-up. Results All patients presented with clinical worsening after initiation of acute stroke treatment. Cerebral revascularization was performed 9.6 hours (SD 9.0) after clinical worsening. All patients had preoperative MRI PDM. No bypass complications, such as anastomosis failure or postoperative hemorrhage, occurred. MRI diffusion ratio before and after bypass was stable or improved in 7 patients and progressed in 1 patient without clinical worsening. MRI PDM and perfusion improved in all 4 patients who underwent postoperative MRI. Clinical outcome was favorable with a median improvement of 7 points on National Institutes of Health Stroke Scale and of 2 points on modified Rankin Scale at last follow-up. Conclusions Based on an algorithm indicating salvageable brain tissue, cerebral revascularization can be safely performed in an emergency setting in a highly selected group of patients with acute ischemic stroke with favorable clinical outcome.