Methods and systems for establishing retrograde carotid arterial blood flow
Interventional procedures on the carotid arteries are performed through a transcervical access while retrograde blood flow is established from the internal carotid artery to a venous or external location. A system for use in accessing and treating a carotid artery includes an arterial access device, a shunt fluidly connected to the arterial access device, 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. The flow control assembly includes one or more components that interact with the blood flow through the shunt.
1. A method for accessing and treating a carotid artery, comprising:
percutaneously forming a transcervical access site in a neck of a patient to form an entryway through a wall of a common carotid artery, wherein the access site is located at distance of 5 cm to 7 cm below a bifurcation location where the patient's common carotid artery bifurcates into the internal carotid artery and external carotid artery;
positioning an arterial access sheath through the entryway, wherein the arterial access sheath has a predetermined working length configured to insert into the common carotid artery, wherein the working length of the arterial access sheath is 5 cm to 15 cm;
inserting no more than the working length of the arterial access sheath into the common carotid artery; and
aspirating blood into the sheath from the internal carotid artery.
2. A method as in claim 1 , further comprising placing a distal embolic filter through the sheath and positioning the filter distal to a treatment site in an artery.
3. A method as in claim 2 , further comprising:
ceasing aspiration of blood after the filter is positioned distal to the treatment site;
performing a treatment at the treatment site;
removing the filter while aspirating blood into the sheath.
4. A method as in claim 1 , wherein aspirating blood comprises actively pumping blood from the arterial access sheath to a return site.
5. A method as in claim 4 , wherein the return site is a venous return site.
6. A method as in claim 4 , wherein the return site is an external reservoir.
7. A method as in claim 4 , wherein the return site is a device that performs the aspiration.
8. A method as in claim 4 , wherein the shunt is attached to a pump and wherein actively pumping comprises activating the pump to draw blood into the shunt via the sheath.
9. A method as in claim 1 , wherein the aspiration device is a syringe and wherein aspirating blood comprises operating the syringe to draw blood into the shunt via the sheath.
10. A method as in claim 1 , further comprising inserting a stent into a treatment site in at least one of the common carotid artery and the internal carotid artery via the arterial access sheath.
11. A method as in claim 1 , further comprising adjusting a flow rate of blood aspirated into the sheath.
12. A method as in claim 1 , further comprising measuring a flow rate of blood aspirated into the sheath.
13. A method as in claim 1 , further comprising blocking blood flow from the common carotid artery past the sheath.
14. A method for accessing and treating a carotid artery, comprising:
percutaneously forming a transcervical access site in a neck of a patient to form an entryway through a wall of a common carotid artery, the access site located at distance below a bifurcation location where the patient's common carotid artery bifurcates into an internal carotid artery and external carotid artery;
positioning an arterial access sheath through the entryway, wherein the arterial access sheath has a working length configured to be inserted into the common carotid artery;
inserting no more than the working length of the arterial access sheath into the common carotid artery; and
aspirating blood into the sheath from the internal carotid artery and into a shunt that extends outward from the sheath;
flowing blood from the shunt into a receptacle, the receptacle being positioned at a height;
regulating a flow rate of blood into the receptacle by varying the height of the receptacle to vary a pressure gradient between the common carotid artery and the receptacle.
15. A method as in claim 14 , wherein varying the height of the receptacle comprises increasing or decreasing the height to increase a fluid pressure in the reservoir to a pressure that is greater than venous pressure.
16. A method as in claim 14 , wherein varying the height of the receptacle comprises increasing or decreasing the height to reduce a fluid pressure in the reservoir to a pressure that is less than venous pressure.
17. A method as in claim 14 , wherein varying the height of the receptacle comprises increasing or decreasing the height so that fluid pressure in the reservoir is different than atmospheric pressure.
18. A method as in claim 14 , further comprising inserting a stent into an artery via the sheath.
19. A method as in claim 14 , further comprising filtering the aspirated blood and returning the blood to the patient.
20. A method as in claim 14 , further comprising adjusting a flow rate of blood aspirated into the sheath.
21. A method as in claim 14 , further comprising measuring a flow rate of blood aspirated into the sheath.