The hospital shall have: Interventional services promptly available 24 hours a day with appropriately trained support staff and equipment, including: Intra-arterial reperfusion therapy; Endovascular treatment of vasospasm; Endovascular ablation of arterial venous malformations; Stenting/angioplasty of extracranial vessels; and Stenting/angioplasty of intracranial vessels; A neurointerventionalist who may be a board-certified/board-eligible neuroradiologist, neurologist, or neurosurgeon on call with a 45-minute arrival time to the hospital; An on-call schedule for primary and back-up neurointerventionalists or neuroradiologists; A written protocol to accept the inter-facility transfer of acute ischemic stroke patients requiring endovascular therapy that includes communication and feedback to the sending facility; and A written protocol to accept the inter-facility transfer of acute stroke patients requiring a higher level of care.