Endovascular flow direction indicator

• US 8,956,397 B2
• Filed: 12/27/2010
• Issued: 02/17/2015
• Est. Priority Date: 12/31/2009
• Status: Active Grant

• Current Assignee: Japan Lifeline Co., Ltd.
• Original Assignee: Endospan Ltd.
• Inventors: Shalev, Alon, Raz, Sagi
• Primary Examiner(s): TANNER, JOCELIN C
• Application Number:
  US13/519,971
• Publication Number:
  US 20120316634A1
• Time in Patent Office: 1,513 Days
• Field of Search: 606/159, 606/200, 606110-115, 606/191, 606/198, 606/192, 606/194, 606/108, 606/167, 606/170, 606/127, 606/128, 623/1.11, 604104-109
• US Class Current: 623/1.11
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 17/1215 comprising additional materials, e.g. thrombogenic, having filaments, having fibers, being coated
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61B 2090/0807 Indication means
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts

Abstract

An endovascular tool is provided, which includes a longitudinal delivery shaft and a fin coupled to the delivery shaft. The fin is configured to assume a compressed state for endoluminal delivery, and an expanded state for endoluminal deployment, in which state the fin is configured to pivot around an axis of rotation. Other embodiments are also described.

Claims

1. Apparatus comprising an endovascular tool, which comprises:

a longitudinal delivery shaft; and

a fin, which (1) is coupled to the delivery shaft, (2) comprises a structural member and at least one substantially flow-resistant membrane member, which is securely mounted to at least a portion of the structural member, and (3) which is configured to assume (a) a compressed state for endoluminal delivery, and (b) an expanded state for endoluminal deployment, in which state (i) the fin is configured to pivot around an axis of rotation that coincides with a longitudinal axis of a portion of the delivery shaft, (ii) the fin extends laterally from the portion of the delivery shaft, which portion has first and second ends, from which respective first and second portions of the structural member of the fin extend in a same radial direction from the longitudinal axis, and (iii) the fin has a substantially planar shape and extends in the same radial direction from the longitudinal axis,

wherein the fin is shaped so as to define one or more pivot joints, which rotatably couple the fin to the portion of the delivery shaft, and

wherein the delivery shaft is capable of rotating within the one or more pivot joints.

2. The apparatus according to claim 1, wherein the fin is configured such that, when the fin is placed in a blood flow path, at least a portion of the fin pivots in a direction that is indicative of a direction of blood flow in a vicinity of the fin.

3. The apparatus according to claim 1, wherein the endovascular tool further comprises a support structure, which is coupled to the delivery shaft, and wherein the fin is coupled to the support structure, so as to be indirectly coupled to the delivery shaft.

4. The apparatus according to claim 1, wherein the substantially flow-resistant membrane member comprises an implantable-grade polymer.

5. The apparatus according to claim 1, wherein a length of the delivery shaft is at least 10 times a greatest dimension of the fin measured in a direction parallel with the axis of rotation when the fin is in its expanded state.

6. The apparatus according to claim 1, further comprising a generally tubular outer shaft, in which the delivery shaft is at least partially positioned, and in which the fin is initially positioned in its compressed state at least partially alongside the delivery shaft.

7. The apparatus according to claim 6, wherein the fin is initially positioned in its compressed state near a distal end of the outer shaft, and wherein, when the fin is in its expanded state upon delivery through the distal end of the outer shaft, at least a portion of the one or more pivot joints is disposed distally to a proximal-most end of the fin.

8. The apparatus according to claim 1, wherein the fin is configured such that when the fin is placed in a blood flow path, the fin pivots such that the radial direction of the fin from the axis of rotation coincides with a direction of blood flow in a vicinity of the fin.

9. The apparatus according to claim 1, wherein the one or more pivot joints and the delivery shaft are configured to provide a coefficient of static friction between the one or more pivot joints and the delivery shaft of no more than 0.5.

10. The apparatus according to claim 1, wherein the one or more pivot joints and the delivery shaft are configured such that the one or more pivot joints rotate with respect to the delivery shaft even when the fin is positioned in a blood flow of a healthy peripheral artery having a diameter of at least 3 mm in a subject having a systolic to diastolic blood pressure gradient of at least 30 mmHg.

11. The apparatus according to claim 1, wherein the fin is pivotable to rotate at least 180 degrees around the axis of rotation, at least when the fin is in its expanded state.

12. The apparatus according to claim 1, wherein an element of the fin is shaped so as to define the one or more pivot joints, the element selected from the group consisting of:

the structural member and the substantially flow-resistant membrane member.

13. The apparatus according to claim 1, wherein the fin is shaped so as to define two or more pivot joints, and wherein the delivery shaft is capable of rotating within the two or more pivot joints.

14. The apparatus according to claim 1, wherein at least one of the one or more pivot joints is axially fixed to the delivery shaft so as to prevent axial motion of the at least one of the one or more pivot joints with respect to the delivery shaft.

15. The apparatus according to claim 14, wherein exactly one of the one or more pivot joints is axially fixed to the delivery shaft.

16. The apparatus according to claim 14, wherein two or more of the pivot joints are axially fixed to the delivery shaft.

17. Apparatus comprising an endovascular tool, which comprises:

a longitudinal delivery shaft; and

a fin, which is coupled to the delivery shaft, and which is configured to assume (a) a compressed state for endoluminal delivery, and (b) an expanded state for endoluminal deployment, in which state (i) the fin is configured to pivot around an axis of rotation, (ii) the fin extends laterally from a portion of the delivery shaft, (iii) a longitudinal axis of the portion coincides with the axis of rotation, and (iv) the fin has a planar shape,

wherein the fin is shaped so as to define one or more pivot joints, which rotatably couple the fin to the portion of the delivery shaft,

wherein the delivery shaft is capable of rotating within the one or more pivot joints, and

wherein the fin comprises a structural member and at least one substantially flow-resistant membrane member, which is securely mounted to at least a portion of the structural member.

18. Apparatus comprising an endovascular tool, which comprises:

a longitudinal delivery shaft; and

a fin, which is coupled to the delivery shaft, and which is configured to assume (a) a compressed state for endoluminal delivery, and (b) an expanded state for endoluminal deployment, in which state (i) the fin is configured to pivot around an axis of rotation, (ii) the fin extends laterally from a portion of the delivery shaft in exactly one radial direction, (iii) a longitudinal axis of the portion coincides with the axis of rotation, and (iv) the fin has a substantially planar shape,

wherein the fin is shaped so as to define one or more pivot joints, which rotatably couple the fin to the portion of the delivery shaft,

wherein the delivery shaft is capable of rotating within the one or more pivot joints, and

wherein the fin comprises a structural member and at least one substantially flow-resistant membrane member, which is securely mounted to at least a portion of the structural member.

19. A method comprising:

providing an endovascular tool including a longitudinal delivery shaft and a fin, which (a) is coupled to the delivery shaft, and (b) comprises a structural member and at least one substantially flow-resistant membrane member, which is securely mounted to at least a portion of the structural member;

endoluminally introducing the endovascular tool into one or more blood vessels of a subject while the fin is in a compressed state; and

thereafter, transitioning the fin to an expanded state, in which state (a) the fin is configured to pivot around an axis of rotation that coincides with a longitudinal axis of a portion of the delivery shaft, (b) the fin extends laterally from the portion of the delivery shaft, which portion has first and second ends, from which respective first and second portions of the structural member of the fin extend in a same radial direction from the longitudinal axis, and (c) the fin has a substantially planar shape and extends in the same radial direction from the longitudinal axis,

wherein the fin is shaped so as to define one or more pivot joints, which rotatably couple the fin to the portion of the delivery shaft, and

wherein the delivery shaft is capable of rotating within the one or more pivot joints.

20. The method according to claim 19, further comprising, after transitioning, generating a radiographic image of the fin using an imaging system.

21. The method according to claim 20, further comprising changing a spatial attitude of a component of the imaging system, responsively to the radiographic image, such that an image plane of the imaging system is generally parallel to a plane defined by the fin that is indicative of a direction of blood flow in a vicinity of the fin.

22. The method according to claim 20, further comprising changing a spatial attitude of a component of the imaging system until an apparent shape of the fin, as shown in the radiographic image, no longer has a modified aspect ratio compared to its actual aspect ratio.

23. The method according to claim 20, further comprising, after generating the image, assessing one or more apparent dimensions of the fin as shown in the image.

24. The method according to claim 23, wherein assessing comprises assessing two or more apparent dimensions of the fin, and assessing at least one ratio between two of the two or more apparent dimensions.

25. The method according to claim 23, further comprising, after generating the image, assessing a reference dimension of a portion of the delivery shaft, and comparing the one or more apparent dimensions of the fin with the reference dimension.

26. The method according to claim 23, further comprising, after assessing, comparing the one or more apparent dimensions with one or more respective actual dimensions of the fin in its expanded state.

27. The method according to claim 23, further comprising changing a spatial attitude of a component of the imaging system responsively to the assessing.

28. The method according to claim 27, wherein changing comprises changing the spatial attitude of the component such that an image plane of the imaging system is generally parallel to a plane defined by the fin that is indicative of a direction of blood flow in a vicinity of the fin. orienting the stent comprises orienting the lateral opening, and

wherein orienting the lateral opening comprises orienting the lateral opening to face in a direction that is parallel to the image plane.

29. The method according to claim 20, further comprising:

changing a spatial attitude of a component of the imaging system, responsively to the radiographic image; and

after changing the spatial attitude;

withdrawing the endovascular tool;

introducing a medical device into vasculature of the subject; and

orienting the medical device using one or more images generated by the imaging system.

30. The method according to claim 29,

wherein the medical device is a stent, and wherein introducing and orienting comprises introducing and orienting the stent,

wherein the stent is shaped so as to define a lateral opening, and wherein orienting the stent comprises orienting the lateral opening, and

wherein orienting the lateral opening comprises orienting the lateral opening to face in a direction that is parallel to the image plane.

31. The method according to claim 19, wherein endoluminally introducing comprises:

positioning the fin in a vicinity of a branching from a main blood vessel to two branching blood vessels, which main and branching blood vessels include the one or more blood vessels; and

positioning the delivery shaft in the one or more blood vessels such that the fin is aligned with the branching.

32. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool further including a support structure, which is coupled to the delivery shaft, and wherein the fin is coupled to the support structure, so as to be indirectly coupled to the delivery shaft.

33. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool further including a generally tubular outer shaft, and wherein endoluminally introducing comprises endoluminally introducing the outer shaft in which the delivery shaft is at least partially positioned, and in which the fin is initially positioned in its compressed state at least partially alongside the delivery shaft.

34. The method according to claim 33,

wherein endoluminally introducing comprises endoluminally introducing the outer shaft in which the fin is initially positioned in its compressed state near a distal end of the outer shaft, and delivering the fin through the distal end of the outer shaft, and

wherein transitioning comprises transitioning the fin to its expanded state, in which state at least a portion of the one or more pivot joints is disposed distally to a proximal-most end of the fin.

35. The method according to claim 19, wherein providing the endovascular tool comprises providing the fin configured such that when the fin is placed in a blood flow path of the one or more blood vessels, the fin pivots such that the radial direction of the fin from the axis of rotation coincides with a direction of blood flow in a vicinity of the fin.

36. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool in which the one or more pivot joints and the delivery shaft are configured to provide a coefficient of static friction between the one or more pivot joints and the delivery shaft of no more than 0.5.

37. The method according to claim 19,

wherein the one or more blood vessels includes a healthy peripheral artery having a diameter of at least 3 mm,

wherein the subject has a systolic to diastolic blood pressure gradient of at least 30 mmHg, and

wherein transitioning comprises transitioning the fin to the expanded state, in which state the one or more pivot joints and the delivery shaft are configured such that the one or more pivot joints rotate with respect to the delivery shaft when the fin is positioned in a blood flow of the healthy peripheral artery.

38. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool in which the fin is pivotable to rotate at least 180 degrees around the axis of rotation, at least when the fin is in its expanded state.

39. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool in which an element of the fin is shaped so as to define the one or more pivot joints, the element selected from the group consisting of:

the structural member and the substantially flow-resistant membrane member.

40. The method according to claim 19, further comprising, after transitioning the fin to the expanded state, ascertaining a direction of blood flow in a vicinity of the fin.

41. The method according to claim 19, wherein endoluminally introducing the endovascular tool comprises positioning the endovascular tool such that the axis of rotation is generally perpendicular to a direction of blood flow in a vicinity of the axis of rotation.

42. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool in which the fin is shaped so as to define two or more pivot joints, and in which the delivery shaft is capable of rotating within the two or more pivot joints.

43. The method according to claim 19, wherein providing the endovascular tool comprises providing the endovascular tool in which at least one of the one or more pivot joints is axially fixed to the delivery shaft so as to prevent axial motion of the at least one of the one or more pivot joints with respect to the delivery shaft.