Cannula Systems and Methods

• US 20120059213A1
• Filed: 09/07/2011
• Published: 03/08/2012
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Paul A. Spence
• Original Assignee: Paul A. Spence
• Inventors: Spence, Paul A.
• Granted Patent: US 9,463,268 B2
• Time in Patent Office: Days
• US Class Current: 600/16
• CPC Class Codes: A61B 2017/1135 End-to-side connections, e.g. T- or Y-connections
• CPC Class Codes: A61M 1/3653 Interfaces between patient blood circulation and extra-corporal blood circuit
• CPC Class Codes: A61M 1/3656 Monitoring patency or flow at connection sites; Detecting disconnections
• CPC Class Codes: A61M 1/3659 Cannulae pertaining to extracorporeal circulation
• CPC Class Codes: A61M 60/20 Type thereof
• CPC Class Codes: A61M 60/861 Connections or anchorings for connecting or anchoring pumps or pumping devices to parts of the patient's body
• CPC Class Codes: A61M 60/873 specially adapted for wireless or transcutaneous energy transfer [TET], e.g. inductive charging
• CPC Class Codes: A61M 60/88 Percutaneous cables

Abstract

Disclosed herein is a cannula assembly for directing the flow of material from an organ chamber, e.g., blood from the left chamber of the heart, and methods of placing the cannula assembly in fluidic communication with the chamber. The cannula assembly includes an elongate tubular member and a coupling assembly disposed at the distal end of elongate tubular member. The elongate tubular member includes a lumen extending from a distal opening at the distal end to a proximal opening at the proximal end. The coupling assembly includes a retaining element and a retention member configured to cooperate with each other and with the portion of the organ wall surrounding the opening in the wall to couple or anchor cannula system to the wall and to provide fluidic communication between the distal opening of the elongate tubular member and the organ chamber.

Claims

1. A cannula system to direct the flow of material from a chamber of an organ via a wall of the organ, comprising

a hollow retention member having a proximal end, a distal end, an outer surface, and a lumen extending between the proximal end and the distal end, the distal end being expandable between a first configuration and a second configuration in which the perimeter of the outer surface of the distal end is larger than the perimeter of the outer surface of the proximal end;

an elongate tubular member having a distal end with a distal opening, a proximal end with a proximal opening, and a lumen extending therebetween, the distal end of the tubular member configured to cooperate with one or both of the retention member and the organ wall to trap the outer surface of the retention member to the chamber side of the organ wall with the lumen of the tubular member in fluid communication with the lumen of the retention member; and

at least one retaining element configured to anchor one or both of (a) at least a portion of the outer surface of the hollow retention member to the chamber side of the organ wall and (b) the tubular member to the organ wall outside the chamber.

2. The cannula system of claim 1, wherein the distal opening of the tubular member is flared, at least a portion the distal opening having a perimeter larger than the perimeter of the outer surface of the proximal end of the retention member.

3. The cannula system of claim 2, wherein the retention member includes a stent that is expandable to a shape that conforms to that of the inner surface of the flared distal opening of the elongate tubular member.

4. The cannula system of claim 1, wherein the retention member includes a stent having a plurality of elongate struts and wherein the retaining element includes one or more of the elongate struts.

5. The cannula system of claim 4, wherein the stent is self-expanding and further comprising a sheath configured to retain the stent therein with the distal end of the stent in its first configuration and from which the stent can be removed to allow the distal end of the stent to expand to its second configuration.

6. The cannula system of claim 4, further comprising a balloon that is inflatable from a first, deflated configuration to a second, inflated configuration;

the stent configured to be mounted on the balloon and to be expanded to the second configuration in which the perimeter of the outside surface of the distal end of the stent is larger than the perimeter of the outside surface of the proximal end of the stent by inflation of the balloon to the second, expanded configuration.

7. The cannula system of claim 2, further comprising a reinforcement element disposed about an outside surface of the distal end of the elongate tubular member.

8. The cannula system of claim 1, wherein the at least one retaining element includes a plurality of barbs extending from the outer surface of the retention member.

9. The cannula system of claim 1, wherein the at least one retaining element includes a plurality of barbs extending from an inner surface of the distal opening of the elongate tubular member.

10. The cannula system of claim 1, wherein the at least one retaining element includes at least one annular ring disposed on the distal side of the organ and configured to anchor the tubular member outside the organ wall.

11. The cannula system of claim 2, wherein the at least one retaining element includes a spring compressible between a first configuration and a second configuration that conforms to that of the inner surface of the flared distal opening of the elongate tubular member to anchor the distal end of the tubular member outside the organ wall.

12. The cannula system of claim 1, wherein the distal opening of the elongate tubular member is integral with the proximal end of the retention member.

13. The cannula system of claim 12, wherein the at least one retaining element includes a circumferential member configured to anchor the organ wall to the outer surface of the retention member.

14. The cannula system of claim 12, wherein the at least at one retaining element includes a retaining arm integrated into the tubular member and being foldable between a first folded configuration and a second unfolded configuration, and further comprising a sheath to retain the retaining arm therein in the first folded configuration against the outer surface of the tubular member and from which the retaining arm may be removed to allow the arm to unfold to its second unfolded configuration to trap the organ wall between the outer surface of the retention member and the retaining arm.

15. The cannula system of claim 12, wherein the distal end of the retention member is self expanding.

16. The cannula system of claim 15, wherein the distal end of the retention member comprises a plurality of leaves.

17. The cannula system of claim 16, further comprising a removable compression member to compress the retention member in its first configuration for insertion and which when removed allows the retention member to expand to its second configuration.

18. The cannula system of claim 17, wherein said compression member is selected from the group consisting of a sheath, a compression tip, a suture, and a combination thereof.

19. The cannula system of claim 1, wherein the distal end of the retention member comprises a textured surface at the interface of the retention member and the organ wall.

20. The cannula system of claim 19, further comprising a circumferential step formed at the junction between the textured surface and the retention member.

21. The cannula system of claim 1, wherein the distal end of the retention member comprises a material that promotes tissue ingrowth at the interface of the retention member and the organ wall.

22. The cannula system of claim 21, further comprising a circumferential step formed at the junction between the material and the retention member.

23. The cannula system of claim 2, wherein the elongate tubular member further includes at least one guidewire within a wall of the elongate tubular member to adjust the orientation of the flared distal opening relative to the proximal end of the elongate tubular member.

24. The cannula system of claim 1, further comprising a sleeve configured to be disposed between the retention member and the distal opening of the tubular member so that the organ wall can be trapped by the retention member between the sleeve and the distal opening of the tubular member.

25. The cannula system of claim 1, wherein the organ is a heart, the chamber is a left atrium, the chamber wall is one of an atrial septum and an external wall of the left atrium, the material is blood, and the elongate tubular member is an inflow tube for a blood pump.

26. A method of placing a cannula into fluidic communication with a chamber of an organ of a patient, the cannula having (i) an elongate tubular member with a lumen having a distal opening at a distal end thereof and a proximal opening at the proximal end thereof, (ii) a hollow retention member disposed at the distal end of the tubular member, the retention member including an outer surface and a lumen extending between a proximal end and distal end thereof, wherein the distal end of the hollow retention member is expandable between a first configuration and a second configuration in which the perimeter of the outer surface of the distal end is larger than the perimeter of the outer surface of the proximal end and wherein the lumen of the retention member at the proximal end is in fluidic communication with the distal end of the elongate tubular member, and (iii) a retaining element configured to trap one or both of (a) at least a portion of the outer surface of the retention member to the chamber side of the organ wall and (b) the tubular member to the organ wall outside the chamber, the method comprising:

advancing the cannula to the chamber;

disposing the retention member in the first configuration through an opening in a wall of the organ into the chamber so that the retention member is disposed inside the chamber of the organ and the lumen at the proximal end of the retention member is in fluid communication with the lumen at the distal end of the tubular member that is outside the chamber;

expanding the retention member to the second configuration;

trapping the retention member to a portion of the chamber side of the wall surrounding the opening in the wall with at least a portion of the trapped wall conforming to the shape of the retention member in its second configuration.

27. The method of claim 26, wherein the retention member includes a stent having a plurality of elongate struts and wherein the retaining element includes one or more of the elongate struts.

28. The method of claim 26, wherein the distal opening of the tubular member is flared in that at least a portion of the distal opening has a perimeter larger than the perimeter of the outer surface of the proximal end of the retention member and the trapping step comprises placing the proximal end of the retention member into the distal opening of the tubular member.

29. The method of claim 28, wherein the retention member includes a stent that is expandable to a second configuration having a shape that conforms to that of the inner surface of the flared distal opening of the elongate tubular member.

30. The method of claim 29, wherein the stent is self-expanding and is retained in its first configuration by placing the stent in a sheath and is expanded to its second configuration by removing the sheath.

31. The method claim 30, further comprising as last steps anchoring the inner surface of the flared distal opening of the elongate tubular member to the organ wall outside the chamber and removing the retention member from the inside chamber of the organ through the hole in the wall and the elongate tubular member.

32. The method of claim 31, wherein the removing step comprises reconfiguring the retention member to its first configuration as it moves through the hole in the wall and the elongate tubular member.

33. The method of claim 32, wherein said step of removing comprises placing the stent in a sheath to reconfigure the stent into the first configuration and withdrawing the stent within the sheath from the organ chamber.

34. The method of claim 29, wherein the stent is mounted on a balloon in the first configuration and is expanded to its second configuration by inflating the balloon.

35. The method of claim 26, wherein the distal opening of the elongate tubular member is integral with the proximal end of the retention member.

36. The method of claim 35, wherein the distal end of the retention member is self-expanding and the trapping step comprise causing circumferential contact between the outer surface of the retention member and the chamber side of the wall with a retaining element.

37. The method of claim 36, wherein the retention member is retained in the first configuration with a compression element.

38. The method of claim 37, wherein the compression element is selected from the group consisting of a sheath, a compression tip, a suture, a forceps, and a combination thereof.

39. The method of claim 36, wherein the retaining element is integral with the elongate tubular member.

40. The method of claim 26, wherein the distal end of the retention member comprises a textured surface at the interface of the retention member and the organ wall.

41. The method of claim 40, further comprising a circumferential step formed at the junction between the textured surface and the retention member.

42. The method of claim 26, wherein the distal end of the retention member comprises a material that promotes tissue ingrowth at the interface of the retention member and the organ wall.

43. The method of claim 42, further comprising a circumferential step formed at the junction between the material and the retention member.

44. The method of claim 26, wherein the organ is a heart, the chamber is a left atrium, the chamber wall is one of an atrial septum and an external wall of the left atrium, the material is blood, and the elongate tubular member is an inflow tube for a blood pump.

45. A cannula system to direct the flow of material from a chamber of an organ via a wall of the organ, comprising

an inflow tube having a proximal end, a distal end, an outer surface, and a lumen extending between the proximal end and the distal end, wherein the distal end comprises a plurality of leaves, is capable of self expanding between a first configuration and a second configuration in which the perimeter of the outer surface of the distal end is larger than the perimeter of the outer surface of the proximal end, and comprises a material that promotes tissue ingrowth at the interface of the retention member and the organ wall;

wherein the material forms a circumferential step formed at the junction between the material and the retention member;

at least one retaining element configured to anchor at least a portion of the outer surface of the distal end to the chamber side of the organ wall; and

at least one removable compression element configured to retain at least the distal end of the inflow tube in the first configuration comprising a sheath.

46. A cannula system to direct the flow of material from a chamber of an organ via a wall of the organ, comprising

a inflow tube having a proximal end, a distal end, an outer surface, and a lumen extending between the proximal end and the distal end, wherein the distal end comprises a plurality of leaves, is capable of self expanding between a first configuration and a second configuration in which the perimeter of the outer surface of the distal end is larger than the perimeter of the outer surface of the proximal end, and comprises a material that promotes tissue ingrowth at the interface of the retention member and the organ wall;

wherein the material forms a circumferential step formed at the junction between the material and the retention member;

at least one retaining element configured to anchor at least a portion of the outer surface of the distal end to the chamber side of the organ wall; and

at least one removable compression element configured to retain at least the distal end of the inflow tube in the first configuration comprising a compression tip.

47. A method of coupling an inflow tube of a blood pump to the atrial septum of a patient'"'"'s heart, in fluidic communication with the left atrium of the heart, the inflow tube having a proximal end, a tubular body, a distal end, an outer surface, and a lumen extending between a proximal opening at the proximal end and a distal opening at the distal end and being initially disposed on a delivery catheter, the distal end of the inflow tube being self-expandable between a first configuration in which the distal opening is substantially closed, and a second configuration in which the distal opening is open and in which the perimeter of the outer surface of the distal end is larger than the perimeter of the outer surface of the tubular body, the catheter including a compression element movable between a first, engaged position in which the compression element is engaged with the distal end to maintain the distal end in the first configuration a second, released position in which the compression element is disengaged from the distal end and allows the distal end to self-expand to the second configuration, the method comprising:

advancing the distal end of the inflow tube distally through the right atrium of the heart, through an opening in the atrial septum, and at least partially into the left atrium of the heart;

moving the retention member from its first, engaged position to its second, released position in the first configuration thereby allowing the distal end to move to its second configuration and to establish fluidic communication between the left atrium and the distal opening;

withdrawing the distal end of the inflow tube proximally to engage the outer surface of the distal end with the atrial septum; and

anchoring the distal end of the inflow to the atrial septum.