Systems for establishing retrograde carotid arterial blood flow

A system (100) for use in accessing and treating a carotid artery, said system comprising: an arterial access device (110) comprising a sheath having an internal lumen, the sheath being adapted to be inserted into a common carotid artery through a transcervical incision and receive blood flow into the internal lumen from the common carotid artery; a shunt (120) fluidly connected to the arterial access device, wherein the shunt has an internal lumen that provides a path for blood to flow from the internal lumen of the sheath to a return site; a hemostasis valve (625) located at the proximal end of a proximal extension, the hemostasis valve adapted to inhibit blood flow out of the inner lumen of the proximal extension while allowing introduction of the catheter into the inner lumen of the proximal extension and in the internal lumen of the sheath; a tube (705) received coaxially over a portion of the outside of the sheath distal section such that a portion of the sheath distal section is covered by the tube and a portion of the sheath distal section is exposed, being the tube arranged to limit insertion of the sheath into a carotid artery to the exposed portion characterized by said proximal extension (610) having a distal end connected to a proximal end of the sheath at a connection site, the proximal extension having an internal lumen in fluid communication with an internal lumen of the sheath; and a flow control assembly coupled to the shunt and adapted to regulate blood flow through the shunt between at least a first blood flow state and at least a second blood flow state, wherein the flow control assembly flow includes one or more components that interact with blood flow through the shunt.