Non-invasive TRanscutaneous Cervical Vagus Nerve Stimulation as a Treatment for Acute Stroke; Safety and Feasibility Study

Inclusion Criteria: * Male or female patients who are older than 18 years old who have been admitted to neurological intensive care or stroke units with ischemic or hemorrhagic stroke * Patients with symptom onset time within 6 hours or with unknown time of onset and no evidence of acute ischemia on fluid attenuation inversion recovery (FLAIR) imaging * Patients who have given written informed consent prior to undertaking any study-related procedure. Exclusion Criteria: * Patients who have a pre-stroke disability ≥ 2 according to the modified Rankin Score * Patients who have a NIH Stroke Scale/Score (NIHSS) ≤ 4 or ≥30 * Patients who have a NIHSS item 1a ≥2 * Patients who have experienced early dramatic neurological improvement (NIHSS score improvement ≥8) prior to study randomization suggesting resolution of signs/symptoms of stroke * Patients with classical lacunar syndrome * Patients who have local infection, rash or space occupying lesion at the stimulation site * Patients with a prior injury to the vagus nerve (cervical vagotomy) * Patients with conditions that make the positioning of the device not possible such as tonic head deviation or involuntary movements of the head and neck * Patients using medications that can interfere with central neurotransmitter mechanisms potentially involved in the central vagal pathway (complete list is provided below under concomitant medications) * Patients with known severe (\>90% stenosis) bilateral carotid artery disease * Patients with known carotid hypersensitivity * Patients who had undergone bilateral carotid endarterectomy or neck surgery involving the region of carotid triangle * Patients who have low blood pressure (Baseline SBP≤100 mmHg or DBP≤60 mmHg) * Patients who have slow heart rate (Baseline HR≤60/min) * Patients who have high blood pressure (SBP\>220 mmHg or DBP\>130 mmHg) despite initial line of treatment * Patients who have been involved in any investigational study within the previous 90 days * Patients who have any terminal illness such that the patient would not be expected to survive more than 90 days * Pregnant women * Patients with severe hypoglycemia at admission (\<60 mg/dl) * Patient experiencing seizures * Patients with baseline ECG showing first-degree AV block; second- or third-degree atrio-ventricular block with no pacemaker/ICD in place; or ventricular tachycardia/fibrillation * Patients with digitalis toxicity * Patients who are suspected to have an acute coronary syndrome after clinical evaluations (Clinical, ECG, or any related biomarker) * Patients who are scheduled to have an emergent carotid artery angioplasty stenting or endarterectomy * Patients implanted with an electrical and/or neurostimulator device, including but not limited to cardiac pacemaker or defibrillator, vagal neurostimulator, deep brain stimulator, spinal stimulator, bone growth stimulator, or cochlear implant. * Patients implanted with metal cervical spine hardware or having a metallic implant near the GammaCore stimulation site.