Catheter Assembly With User-Assisting Handle

• US 20130103130A1
• Filed: 10/24/2011
• Published: 04/25/2013
• Est. Priority Date: 10/24/2011
• Status: Active Grant

• Current Assignee: NovoStent Corp.
• Original Assignee: NovoStent Corp.
• Inventors: Lubinski, Alexander Arthur, Leopold, Eric W., Martin, Gerald Ray
• Granted Patent: US 8,852,258 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/9517 handle assemblies therefor
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2230/0019 rectangular
• CPC Class Codes: A61F 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility

Abstract

A catheter assembly includes a catheter, including an inner member and a sheath, extending from a handle. The handle includes a housing, a braking assembly, a carriage and a carriage driver. The braking assembly comprises a braking element within the housing interior and a braking element rotator. The carriage comprises at least one carriage braking surface engaging the braking element. The carriage driver, such as a spring, biases the carriage towards the proximal end of the handle. The inner member has a proximal end secured to the housing. The sheath has a proximal end secured to the carriage. Rotating the braking element causes the carriage to move proximally as the carriage braking surface slides along the braking element. This causes the sheath to move proximally relative to the inner member.

Claims

1. A catheter assembly comprising:

a catheter comprising an inner member and a sheath housing the inner member and axially slidable over the inner member;

a handle comprising;

a housing having a proximal end, a distal end and an inner surface, the inner surface defining a housing interior, the housing having a housing axis;

a braking element assembly comprising an elongate braking element located within the housing interior and a braking element rotator operably coupled to the braking element for selective rotation of the braking element about the housing axis;

a carriage located within the housing interior and movable along the housing axis, the carriage comprising at least one carriage braking surface engaging the braking element; and

a carriage driver biasing the carriage towards the proximal end of the handle;

the inner member having a proximal end secured to the housing;

the sheath having a proximal end secured to the carriage; and

whereby operation of the braking element rotator to cause the braking element to rotate in a first rotary direction allowing the carriage to move in a proximal direction, so that the sheath moves proximally relative to the inner member.

2. The catheter assembly according to claim 1, wherein the carriage driver comprises at least one of a spring, a motor drive, an air cylinder drive, and a linear driver.

3. The catheter assembly according to claim 1, wherein the carriage driver comprises a spring, the spring comprising a metal spring, elastomeric spring, a tension spring, a compression spring, a constant force spring, a constant torque spring, or a combination thereof

4. The catheter assembly according to claim 1, wherein the carriage driver comprises a plurality of concentric springs.

5. The catheter assembly according to claim 1, wherein the carriage driver exerts a force on the carriage generally parallel to the axis.

6. The catheter assembly according to claim 1, wherein the sheath is movable in a proximal direction relative to the inner member from a first position to a second position.

7. The catheter assembly according to claim 6, wherein the catheter comprises a distal end and a prosthesis at the distal end, the prosthesis in contact with the inner member and being at least partially covered by the sheath when the sheath is in the first position, the prosthesis being at least substantially uncovered by the sheath when the sheath is in the second position.

8. The catheter assembly according to claim 7, wherein the prosthesis is a self-expanding stent.

9. The catheter assembly according to claim 6, wherein:

an axially directed first force is required to move the sheath from the first position to the second position;

the carriage driver exerts an axially directed second force on the carriage biasing the carriage proximally; and

the first and second forces are variable forces according to the position of the sheath relative to the inner member; and

the second force is greater than the first force at each position of the sheath relative to the inner member between the first and second positions.

10. The catheter assembly according to claim 9, wherein the second force is at least 10% greater than the first force.

11. The catheter assembly according to claim 1, wherein the braking element comprises a helical element.

12. The catheter assembly according to claim 11, wherein the helical element comprises a helical wire having a generally rectangular cross-sectional shape.

13. The catheter assembly according to claim 11, wherein the helical element comprises helical element portions with different pitches so that the amount of the axial movement of the carriage through the rotation of the helical element will depend on the where the carriage is engaging the helical element.

14. The catheter assembly according to claim 11, wherein the helical element comprises a first helical element portion engageable with the carriage during an initial movement of the carriage and a second helical element portion engageable with the carriage during subsequent movement of the carriage, the first and second helical element portions having first and second pitches, respectively, the first pitch being shorter than the second pitch, whereby axial movement of the carriage along the first helical element portion is slower than along the second helical element portion for the same rate of rotation of the helical element, whereby user control can be enhanced during initial movement of the helical element.

15. The catheter assembly according to claim 1, wherein the braking element defines an interrupted braking path.

16. The catheter assembly according to claim 15, wherein the interrupted path comprises curved path sections joined by connecting sections.

17. The catheter assembly according to claim 16, wherein:

at least one of the curved path sections define a curved path having a generally constant axial position and a changing rotary position; and

at least one of the connecting sections defines a path having a changing axial position.

18. The catheter assembly according to claim 16, wherein:

the curved path sections each define a curved path having a changing axial position and a changing rotary position; and

a plurality of the connecting sections define generally straight paths having changing axial positions.

19. The catheter assembly according to claim 15, wherein the braking path comprises a plurality of curved, generally helical sections joined by at least one connecting section.

20. The catheter assembly according to claim 19, wherein said at least one connecting section comprises a generally straight section extending generally parallel to the axis.

21. The catheter assembly according to claim 1, wherein the braking element rotator comprises a user-rotatable deployment knob rotatably mounted to the housing.

22. The catheter assembly according to claim 21, wherein the deployment knob is affixed to the braking element.

23. The catheter assembly according to claim 21, wherein the deployment knob is rotatably mounted to the distal end of the housing in a fixed axial position relative to the housing axis.

24. The catheter assembly according to claim 21, wherein the deployment knob and the housing comprises anti-reverse elements to allow the deployment knob to rotate in one direction only.

25. The catheter assembly according to claim 1, wherein the carriage has a plurality of spaced apart carriage braking surfaces contacting the braking element.

26. The catheter assembly according to claim 1, wherein:

the sheath and inner member define a first region therebetween;

the carriage comprises a flush port fluidly coupled to said first region;

the housing comprises a flush port access opening; and

the flush port being aligned with the flush port access region when the carriage is at a first position;

whereby the first region between the sheath and inner member may be flushed through the flush port.

27. The catheter assembly according to claim 26, wherein:

the flush port is a generally radially extending member; and

the housing has an axially extending extension defining an axially extending pathway along which the flush port can move as the carriage moves in the proximal direction.

28. The catheter assembly according to claim 27, wherein the flush port and the extension of the housing defines complementary axial guide surfaces to aid limiting the movement of the carriage to movement along the housing axis.

29. The catheter assembly according to claim 1, wherein the housing and the carriage define guide elements to aid limiting the movement of the carriage to movement along the housing axis.

30. The catheter assembly according to claim 29, wherein the guide elements comprise axial guide surfaces formed by an outwardly extending fin of the carriage and an axially extending slot formed in the inner surface of the housing.

31. The catheter assembly according to claim 1, wherein the proximal end of the inner member is secured directly to the proximal end of the handle and the proximal end of the sheath is secured directly to the carriage.

32. The catheter assembly according to claim 1, wherein the carriage driver comprises a tension spring having a proximal end coupled to the proximal end of the housing and a distal end coupled to the carriage so that the tension spring exerts a tension force pulling the carriage in a proximal direction.

33. The catheter assembly according to claim 1, wherein the carriage driver comprises a plurality of nested tension springs each having a proximal end coupled to the proximal end of the housing and a distal end coupled to the carriage so that the tension springs exert a tension force pulling the carriage in a proximal direction.

34. The catheter assembly according to claim 33, wherein adjacent nested tension springs have at least one of:

(1) unequal pitches, and (2) opposite directions of wind.

35. The catheter assembly according to claim 1, wherein the carriage driver comprises a spring positioned at least partly within the braking element.

36. The catheter assembly according to claim 1, wherein the carriage driver comprises a compression spring captured between the carriage and the distal end of the housing so that the compression spring exerts a proximally directed force against the carriage.

37. A catheter assembly comprising:

a catheter comprising an inner member and a sheath housing the inner member and axially slidable over the inner member;

a handle comprising;

a housing having proximal and distal ends, and inner and outer surfaces, the inner surface defining a housing interior, the housing having a housing axis;

a braking element assembly comprising a helical element located within the housing interior and a helical element rotator operably coupled to the helical element for selective rotation of the helical element about the housing axis;

the helical element rotator comprising a user-rotatable deployment knob rotatably mounted to the distal end of the housing;

a carriage located within the housing interior and movable along the housing axis, the carriage comprising a carriage braking surface engaging the helical element; and

a carriage driver exerting an axially directed second force on the carriage biasing the carriage towards the proximal end of the handle;

the inner member having a proximal end secured to the housing;

the sheath having a proximal end secured to the carriage, the sheath being movable in a proximal direction relative to the inner member from a first position to a second position;

the catheter comprising a distal end and a prosthesis at the distal end, the prosthesis adjacent to the inner member and being at least partially covered by the sheath when the sheath is in the first position, the prosthesis being at least substantially uncovered by the sheath when the sheath is in the second position;

an axially directed first force being required to move the sheath from the first position to the second position;

the first and second forces being variable forces according to the position of the sheath relative to the inner member between the first and second positions; and

the second force being greater than the first force at each position of the sheath relative to the inner member between the first and second positions;

whereby operation of the helical element rotator to rotate the helical element in a first rotary direction allows the carriage to move in a proximal direction, so that the sheath moves proximally relative to the inner member.

38. The catheter assembly according to claim 37, wherein the vascular prosthesis surrounds the inner member.

39. The catheter assembly according to claim 37, wherein the sheath has a first strength in tension, the maximum second force being less than the first strength.

40. The catheter assembly according to claim 37, wherein the proximal ends of the inner member and the shaft are secured directly to the housing and to the carriage, respectively.