BY-PASS SHUNT TO REDUCE FLOW OUTPUT OF CIRCULATORY ASSIST DEVICE

• US 20130150772A1
• Filed: 12/03/2012
• Published: 06/13/2013
• Est. Priority Date: 12/09/2011
• Status: Active Grant

• Current Assignee: Circulite Inc. (Medtronic Plc)
• Original Assignee: Circulite Inc. (Medtronic Plc)
• Inventors: Farnan, Robert C., Fritz, Bryan, Yi, Yun
• Granted Patent: US 9,724,500 B2
• Time in Patent Office: Days
• US Class Current: 604/8
• CPC Class Codes: A61M 2205/04 implanted
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3337 Controlling, regulating pressure or flow by means of a valve by-passing a pump
• CPC Class Codes: A61M 2240/00 Specially adapted for neonatal use
• CPC Class Codes: A61M 27/002 Implant devices for drainage of body fluids from one part of the body to another intraocular A61F9/00781; middle ear A61F11/202
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: A61M 60/178 drawing blood from a ventricle and returning the blood to the arterial system via a cannula external to the ventricle, e.g. left or right ventricular assist devices
• CPC Class Codes: A61M 60/221 the blood flow through the rotating member having both radial and axial components, e.g. mixed flow pumps
• CPC Class Codes: A61M 60/226 the blood flow through the rotating member having mainly radial components
• CPC Class Codes: A61M 60/237 the blood flow through the rotating member having mainly axial components, e.g. axial flow pumps
• CPC Class Codes: A61M 60/546 of blood flow, e.g. by adapting rotor speed
• CPC Class Codes: A61M 60/592 Communication of patient or blood pump data to distant operators for treatment purposes
• CPC Class Codes: A61M 60/869 Compliance chambers containing a gas or liquid other than blood to compensate volume variations of a blood chamber
• CPC Class Codes: A61M 60/88 Percutaneous cables
• CPC Class Codes: A61M 60/892 Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood

Abstract

A by-pass shunt for use with a bodily fluid pump. The by-pass shunt includes an inflow conduit, an outflow conduit, and an intermediate conduit fluidically coupling the inflow and outflow conduits. A flow restrictor is operably coupled to a portion of the intermediate conduit and is configured to reduce a fluid flow from the outflow conduit, through the intermediate conduit, and into the inflow conduit.

Claims

1. A by-pass shunt for a pump that is configured to pump bodily fluids with variable outflow volume, the by-pass shunt comprising:

an inflow conduit;

an outflow conduit;

an intermediate conduit fluidically coupling the inflow and outflow conduits; and

a flow restrictor operably coupled to a portion of the intermediate conduit and configured to reduce a fluid flow from the outflow conduit, through the intermediate conduit, and into the inflow conduit.

2. The by-pass shunt of claim 1, where the flow restrictor is adjustable so as to enable at least a decrease in the fluid flow through the intermediate conduit.

3. The by-pass shunt of claim 2, wherein the flow restrictor is capable of being adjusted while the pump is in use.

4. The by-pass shunt of claim 1, wherein the intermediate conduit includes an inflow end, an outflow end, and a lumen extending therebetween, and the flow restrictor decreases a diameter of the lumen of the intermediate conduit in at least one location between the inflow end and the outflow end.

5. The by-pass shunt of claim 1, wherein the intermediate conduit includes a compliant portion that is deformable between a first diameter state and a second diameter state, said first diameter state being expanded to a larger diameter than said second diameter state.

6. The by-pass shunt of claim 5, wherein the flow restrictor further comprises:

a housing forming a fluid-tight chamber surrounding the compliant portion; and

an inlet port fluidically coupled to the fluid-tight chamber.

7. The by-pass shunt of claim 5, wherein the flow restrictor further comprises:

a housing forming a piston chamber surrounding the compliant portion; and

a piston positioned within the piston chamber and configured to inwardly deform a portion of the compliant portion.

8. The by-pass shunt of claim 7, wherein the housing further comprises:

an inlet port fluidically coupled to the piston chamber; and

an access port device fluidically coupled to the inlet port and configured to provide fluidic accessibility to an inflation fluid of the piston chamber.

9. The by-pass shunt of claim 5, wherein the flow restrictor is an outer balloon located external to and surrounding an outer surface of the compliant portion.

10. The by-pass shunt of claim 1, wherein the flow restrictor is an inner balloon coupled to an inner surface of the intermediate conduit.

11. The by-pass shunt of claim 1 further comprising:

a mixing chamber coupled to the outflow conduit and configured to retain a volume of the fluid, wherein the intermediate conduit is also in fluid communication with the mixing chamber.

12. A bodily fluid pumping system comprising:

a mechanical pump having an inflow port and an outflow port;

an inflow cannula operably coupled to and extending away from the inflow port;

an outflow cannula operably coupled to and extending away from the outflow port;

an intermediate conduit configured to provide fluid communication between the inflow and outflow cannulae; and

a flow restrictor operably coupled to a portion of the intermediate conduit and configured to reduce a flow of a pumped fluid through the inflow and outflow cannulae.

13. The bodily fluid pumping system of claim 12, wherein the intermediate conduit includes a compliant portion that is deformable between a first diameter state and a second diameter state, said first diameter state being expanded to a larger diameter than said second diameter state.

14. The bodily fluid pumping system of claim 13, wherein the flow restrictor further comprises:

a housing forming a fluid-tight chamber surrounding the compliant portion; and

an inlet port fluidically coupled to the fluid-tight chamber.

15. The bodily fluid pumping system of claim 13, wherein the flow restrictor further comprises:

a housing forming a piston chamber surrounding the compliant portion; and

a piston positioned within the piston chamber and configured to inwardly deform a portion of the compliant portion.

16. The bodily fluid pumping system of claim 13, wherein the flow restrictor is an outer balloon located external to and surrounding an outer surface of the compliant portion.

17. The bodily fluid pumping system of claim 12, wherein the flow restrictor is an inner balloon coupled to an inner surface of the intermediate conduit.

18. The bodily fluid pumping system of claim 12 further comprising:

a mixing chamber coupled to the outflow cannula and configured to retain a volume of fluid, and wherein the intermediate conduit is also in fluid communication with the mixing chamber.

19. A circulatory assist system comprising:

a mechanical pump having an inflow port and an outflow port;

an inflow cannula operably coupled to the inflow port of the pump and extending to a first vascular structure of a patient;

an outflow cannula operably coupled to between the outflow port of the pump and extending to a second vascular structure of the patient;

a by-pass shunt configured to fluidically couple the inflow and outflow cannulae such that a first portion of blood ejected from the mechanical pump flows through the outflow cannula and a second portion of the blood ejected from the mechanical pump flows through the by-pass shunt to the inflow cannula, the by-pass shunt having a compliant portion that is deformable between a first diameter state and a second diameter state, the first diameter state being expanded to a larger diameter than said second diameter state; and

a flow restrictor coupled to the by-pass shunt and configured to transition the compliant portion between the first and second diameter states.

20. The circulatory assist system of claim 19, wherein the flow restrictor further comprises:

a housing forming a fluid-tight chamber surrounding the compliant portion; and

an inlet port fluidically coupled to the fluid-tight chamber.

21. The circulatory assist system of claim 19, wherein the flow restrictor further comprises:

a housing forming a piston chamber surrounding the compliant portion; and

a piston positioned within the piston chamber and configured to inwardly deform a portion of the compliant portion.

22. The circulatory assist system of claim 19, wherein the flow restrictor is an outer balloon located external to and surrounding an outer surface of the compliant portion.

23. The circulatory assist system of claim 19, wherein the flow restrictor is an inner balloon coupled to an inner surface of the by-pass shunt.

24. The circulatory assist system of claim 19 further comprising:

a mixing chamber coupled to the outflow conduit and configured to retain a volume of fluid, and wherein the by-pass shunt is also in fluid communication with the mixing chamber.

25. The circulatory assist system of claim 19, wherein the flow of the first portion of blood ranges from about 0.1 L/min 4 L/min.

26. The circulatory assist system of claim 25, wherein the flow of the first portion of blood ranges from about 0.1 L/min to about 0.3 L/min when the compliant portion is in the first diameter state.

27. The circulatory assist system of claim 25, wherein the flow of the first portion of blood ranges from about 3 L/min to about 4 L/min when the compliant portion is in the second diameter state.

28. The circulatory assist system of claim 19, wherein the by-pass shunt further comprises:

an inflow conduit operably coupling the inflow cannula to the inflow port;

an outflow conduit operably coupling the outflow cannula to the outflow port; and

an intermediate conduit fluidically coupling the inflow and outflow conduits,

wherein the flow restrictor is operably coupled to a portion of the intermediate conduit.

29. A method of assisting cardiac output comprising:

coupling an inflow port of a mechanical pump to a first vascular structure of a patient;

coupling an outflow port of the mechanical pump to a second vascular structure of the patient;

operating the mechanical pump to direct blood flow from the first vascular structure toward the inflow port such that a first portion of the blood flow is directed from the outflow port to the second vascular structure and a second portion of the blood flow is directed from the outflow port into a shunt and reenters the inflow port of the mechanical pump; and

adjusting the flow rate of the first portion of the blood flow by adjusting a flow rate of the second portion of the blood flow.

30. The method of claim 29 further comprising:

decreasing the first portion of the blood flow by increasing the second portion of the blood flow.

31. The method of claim 29 further comprising:

increasing the first portion of the blood flow by decreasing the second portion of the blood flow.

32. The method of claim 29, wherein adjusting the second portion of the blood flow includes actuating a flow restrictor of the shunt.

33. The method of claim 32, wherein actuating the flow restrictor occurs while operating the mechanical pump.

34. The method of claim 29, wherein the shunt includes a compliant portion having a first diameter state and a second diameter state that is smaller than the first diameter state, and restricting the second portion of the blood flow includes deforming the complaint portion of the shunt from the first diameter state to the second diameter state.

35. A method of assisting cardiac output comprising:

coupling an inflow port of a mechanical pump to a first vascular structure of a patient;

coupling an outflow port of the mechanical pump to a second vascular structure of the patient;

operating the mechanical pump to direct blood flow from the first vascular structure toward the inflow port such that a first portion of the blood flow is directed from the outflow port to the second vascular structure and a second portion of the blood flow is directed from the outflow port into a shunt that is in fluid communication with the inflow port of the mechanical pump; and

deforming a portion of the shunt to either increase the first portion of blood flow by decreasing the second portion of blood flow or decrease the first portion of blood flow by increasing the second portion of blood flow.

36. The method of claim 35, wherein deforming the portion of the shunt includes reducing a diameter of a compliant portion of the shunt.

37. The method of claim 35, wherein deforming the portion of the shunt includes inflating a balloon located external to the shunt and surrounding an outer surface of the compliant portion.

38. The method of claim 37, wherein inflating the balloon includes delivering a fluid to the balloon.

39. The method of claim 35, wherein deforming the shunt includes inflating a balloon located within the shunt and forming the complaint portion.

40. The method of claim 39, wherein inflating the balloon includes delivering a fluid to the balloon.

41. The method of claim 35, wherein reducing the diameter includes inflating a balloon operably coupled to the compliant portion or activating a hydraulic piston.

42. The method of claim 35, wherein the first portion of the blood flow ranges from about 0.1 L/min to about 0.3 L/min when the portion of the shunt is deformed to increase the first portion and the blood flow ranges from about 3 L/min to about 4 L/min when the portion of the shunt is deformed to decrease the first portion.

43. The method of claim 35 further comprising:

mixing the second portion of the blood flow from the shunt with blood flow from the first vascular structure at the inflow port.

44. A circulatory assist system comprising:

a mechanical pump having an inflow port and an outflow port;

an inflow cannula operably coupled to the inflow port of the pump and adapted to extend to the heart of a patient;

an outflow cannula operably coupled to the outflow port of the pump and adapted to extend to a vascular structure of the patient;

a shunt configured to provide fluid communication between the inflow port and the outflow cannula; and

a mixing chamber coupled to the outflow port configured to hold a volume of blood.

45. The circulatory assist system of claim 44, wherein the shunt is fluidically coupled to the mixing chamber.

46. The circulatory assist system of claim 44, wherein the inflow port includes a distributor element configured to mix blood entering the inflow port from the shunt with blood entering the inflow port from the inflow cannula.

47. The circulatory assist of claim 46, wherein the distributor element further comprises an annular fluid coupling surrounding the inflow port of the mechanical pump.