System and method to increase the overall diameter of veins
A system and method for increasing the speed of blood and wall shear stress (WSS) in a peripheral vein for a sufficient period of time to result in a persistent increase in the overall diameter and lumen diameter of the vein is provided. The method includes pumping blood at a desired rate and pulsatility. The pumping is monitored and adjusted, as necessary, to maintain the desired blood speed, WSS and pulsatility in the peripheral vein in order to optimize the rate and extent of dilation of the peripheral vein.
1. A system for persistently increasing an overall diameter and a lumen diameter of a peripheral vein prior to creation of an arteriovenous fistula or an arteriovenous graft in a patient, wherein the system is configured to increase the velocity of blood in the peripheral vein, the system comprising:
a pump-conduit assembly to remove deoxygenated blood from a donating vein or the right atrium and pump blood into the peripheral vein, the pump-conduit assembly including:
a pump configured to pump blood, having a pump inlet and a pump outlet;
a first conduit configured to carry blood, the first conduit having an inlet configured to fluidly connect to a donating vein or right atrium to remove the deoxygenated blood from the donating vein or to the right atrium, such first conduit comprising a first catheter configured for insertion into a vein and advancement within the lumen of the vein, including into the right atrium; and an outlet fluidly connected to the pump inlet;
a second conduit configured to carry blood, the second conduit having an inlet fluidly connected to the pump outlet and an outlet to fluidly connect to a peripheral vein, the second conduit comprising a first segment comprising a second catheter and configured to connect to the pump outlet and a second segment configured to enable the creation of a surgical anastomosis between an end of the second segment and the peripheral vein using the end of the second segment to attach to the side of the peripheral vein; and
a control unit configured to control the pump and pump deoxygenated blood into the peripheral vein at a rate to maintain a mean wall shear stress in the peripheral vein between 1.5 Pa and 23 Pa for a period of 7-84 days, wherein the control unit and the pump-conduit assembly are configured to pump blood in a manner such that the mean pulse pressure in the conduit fluidly connected to the peripheral vein is less than 20 mmHg.
2. The system of claim 1 , wherein, the first conduit and a first portion of the second conduit comprises polyvinyl chloride, polyethylene, polyurethane, or silicone.
3. The system of claim 1 , wherein the first conduit is configured for insertion into the subclavian vein, jugular vein, brachiocephalic vein, superior vena cava, femoral vein, external iliac vein, common iliac vein, and inferior vena cava.
4. The system of claim 3 , wherein, the first conduit and a first portion of the second conduit comprises polyvinyl chloride, polyethylene, polyurethane, or silicone.
5. The system of claim 1 , wherein the first conduit or the first portion of the second conduit comprises an antimicrobial coating.
6. The system of claim 3 , wherein the first conduit or the first portion of the second conduit comprises an antimicrobial coating.
7. The system of claim 4 , wherein the first conduit or the first portion of the second conduit comprises an antimicrobial coating.
8. The system of claim 1 , further comprising a cuff that can be affixed to a portion of the first conduit or the second conduit.
9. The system of claim 3 , further comprising a cuff that can be affixed to a portion of the first conduit or the second conduit.
10. The system of claim 4 , further comprising a cuff that can be affixed to a portion of the first conduit or the second conduit.
11. The system of claim 7 , further comprising a cuff that can be affixed to a portion of the first conduit or the second conduit.
12. The system of claim 1 , wherein the second segment of the second conduit configured to enable the creation of a surgical anastomosis between the second segment and the peripheral vein using the end of the segment to attach to the side of the peripheral vein is configured to make such surgical anastomosis to the brachial vein, radial vein, ulnar vein, interosseous vein, femoral vein, profunda vein, superficial femoral vein, popliteal vein, anterior tibial vein, posterior tibial vein, or peroneal vein.
13. The system of claim 1 , wherein the segment of the second conduit configured to enable the creation of a surgical anastomosis between the segment of the second conduit and the peripheral vein comprises PTFE.
14. The system of claim 12 , wherein the segment of the second conduit configured to enable the creation of a surgical anastomosis between the segment of the second conduit and the peripheral vein comprises PTFE.
15. The system of claim 1 , wherein the pump of the pump-conduit assembly is a centrifugal pump.
16. The system of claim 1 , wherein the pump of the pump-conduit assembly is configured to pump blood over an operating range from 50 mL per minute to 1500 mL per minute, or 100 mL per minute to 1000 mL per minute.
17. The system of claim 15 , wherein the pump of the pump-conduit assembly is configured to pump blood over an operating range from 50 mL per minute to 1500 mL per minute, or 100 mL per minute to 1000 mL per minute.
18. The system of claim 1 , wherein the pump of the pump-conduit assembly is driven by an electric motor.
19. The system of claim 1 , wherein a combined length of the first conduit and the second conduit is between 2 cm and 110 cm.
20. The system of claim 1 , wherein the pump portion of the pump-conduit assembly is configured to remain extracorporeal to the patient.
21. The system of claim 1 , wherein the control unit can be manually adjusted to change the speed of the pump of the pump-conduit assembly.
22. The system of claim 1 , wherein the system is configured to pump blood at a rate that maintains a mean wall shear stress in the peripheral vein between 2.5 Pa and 7.5 Pa.
23. The system of claim 1 , wherein the system is configured to pump blood at a rate that maintains a mean blood speed between 15 cm/s and 100 cm/s in the peripheral vein.
24. The system of claim 1 , wherein the system is configured to pump blood at a rate between 50 ml/min and 1500 ml/min.
25. The system of claim 19 , wherein the system is configured to pump blood at a rate between 50 ml/min and 1500 ml/min.
26. The system of claim 20 , wherein the system is configured to pump blood at a rate between 50 ml/min and 1500 ml/min.
27. The system of claim 1 , wherein the pump-conduit assembly and controller are configured for use in a human patient for a period of time up to 42 days, such configuration including the use of the system for a period of time up to 42 days.