Interventional medical systems and associated assemblies and methods

• US 10,398,892 B2
• Filed: 07/21/2016
• Issued: 09/03/2019
• Est. Priority Date: 07/21/2016
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Anderson, Thomas A., Asleson, Andrea J., Eggen, Michael D., Redmond, McKenna Rose, Yang, Zhongping
• Primary Examiner(s): Aleman, Sarah W
• Application Number:
  US15/216,466
• Publication Number:
  US 20180021571A1
• Time in Patent Office: 1,139 Days
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61N 1/0592 Introducing the lead through the pericardium with a needle
• CPC Class Codes: A61N 1/37512 Pacemakers
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators

Abstract

A catheter assembly includes a cap and a spring-biased tethering member coupled thereto. The cap includes first and second portions, and a transition zone extending therebetween. A girth of the first portion is sized to fit within a distal-most opening of the catheter assembly; and a girth of the second portion tapers from a first size at the transition zone, which is too large to fit within the distal-most opening, to a smaller size at a distal end of the cap. The spring-biased tethering member holds the cap in open and closed positions, when the cap first portion extends within the distal-most opening, and when the cap is separated from the distal-most opening, respectively. At the closed position, the first portion is approximately concentric with the distal-most opening, and at the open position, an entirety of the cap is laterally offset from the distal-most opening.

Claims

1. An interventional medical system comprising an implantable medical device and a catheter assembly;

the implantable medical device comprising an electronic controller, a hermetically sealed housing containing the controller, an electrode electrically coupled to the controller, and a fixation member mounted to a distal end of the housing;

the catheter assembly comprising an elongate inner tubular member, an elongate outer tubular member, and an end-cap subassembly;

the outer tubular member defining an elongate lumen in which the inner tubular member extends, the outer tubular member extending from a proximal end of the outer tubular member to a distal terminal end of the outer tubular member, the distal terminal end of the outer tubular member defining a distal-most opening of the elongate lumen, the elongate lumen, in proximity to the distal-most opening, being sized to contain an entirety of the implantable medical device therein, and the distal-most opening allowing passage of the implantable medical device therethrough;

the inner tubular member including a distal end of the inner tubular member configured to engage with a proximal end of the implantable medical device, and the inner tubular member being moveable through the elongate lumen defined by the outer tubular member; and

the end-cap subassembly of the catheter assembly comprising;

a cap including a proximal end of the cap, a distal end of the cap, a first portion extending from the proximal end of the cap, a second portion extending from the distal end of the cap, and a transition zone extending between the first and second portions, the first portion having a girth sized to fit within the distal-most opening of the lumen of the outer tubular member, the second portion having a girth that tapers from a first size at the transition zone to a second, smaller size at the distal end, the girth of the second portion at the transition zone being too large to fit within the distal-most opening of the elongate lumen defined by the outer tubular member; and

a spring-biased tethering member extending within the catheter assembly, a distal end of the spring-biased tethering member being coupled to the cap so that the tethering member extends from the proximal end of the cap, the tethering member being configured extend alongside the implantable medical device when the implantable medical device is contained in the lumen of the outer tubular member; and

wherein, when the first portion of the cap extends within the distal-most opening of the elongate lumen of the outer tubular member, the catheter assembly constrains the spring-biased tethering member in a spring-loaded first configuration;

wherein, when the outer tubular member is retracted relative to the spring-biased tethering member the cap is separated from the distal-most opening of the elongate lumen of the outer tubular member and the spring-biased tethering member is released to extend out from the distal-most opening and to a second configuration in which the spring-biased tethering member holds the cap in an open position, at which an entirety of the cap is laterally offset from the distal-most opening; and

wherein, when in the second configuration, the spring-biased tethering member has a pre-formed curvature comprising a plurality of bends, at least two of the plurality of bends in different directions.

2. The system of claim 1, wherein the spring-biased tethering member of the end-cap subassembly of the catheter assembly comprises a proximal segment and a distal segment, the proximal segment having a length approximately equal to that of the inner tubular member and being in sliding engagement within a lumen of the inner tubular member, and the distal segment having the pre-formed curvature.

3. The system of claim 1, wherein spring-biased tethering member comprises a super-elastic wire having the preformed curvature.

4. The system of claim 3, wherein the super-elastic wire of the spring-biased tethering member has a rectangular cross-section.

5. The system of claim 1, wherein the pre-formed curvature comprises a first bend, a second bend closer to the distal end of the spring-biased tethering member than the first bend, and a third bend closer to the distal end of the spring-biased tethering member than the second bend, the first bend extending around approximately 180 degrees, and each of the second and third bends extending around approximately 90 degrees.

6. The system of claim 1, wherein the end-cap subassembly of the catheter assembly further comprises a radiopaque marker extending around the transition zone of the cap.

7. The system of claim 1, wherein the end-cap subassembly of the catheter assembly further comprises a radiopaque marker extending within the second portion of the cap.

8. The system of claim 1, wherein the end-cap subassembly of the catheter assembly further comprises an atraumatic guide-wire tip being coupled to the cap and extending distally from the distal end of the cap.

9. The system of claim 1, wherein the transition zone of the cap defines an edge that abuts the distal terminal end of the outer tubular member of the catheter assembly when the first portion of the cap is fitted within the distal-most opening of the elongate lumen defined by the outer tubular member.

10. The system of claim 1, wherein the plurality of bends comprises a first bend and a second bend closer to the distal end of the spring-biased tethering member than the first bend, wherein a direction of the second bend is opposite a direction of the first bend.

11. An end-cap subassembly for a catheter assembly, the end-cap subassembly comprising:

a cap including a proximal end of the cap, a distal end of the cap, a first portion extending from the proximal end of the cap, a second portion extending from the distal end, and a transition zone extending between the first and second portions, the first portion having a girth sized to fit within a distal-most opening of a lumen of the catheter assembly, the second portion having a girth that tapers from a first size at the transition zone to a smaller, second size at the distal end, the girth of the second portion at the transition zone being too large to fit within the distal-most opening of the lumen defined by the catheter assembly; and

a spring-biased tethering member coupled to the cap and extending from the proximal end of the cap, the spring-biased tethering member being configured extend within the catheter assembly alongside an implantable medical device that is contained within the lumen;

wherein, when the first portion of the cap extends within the distal-most opening of the lumen of the catheter assembly, the catheter assembly constrains the spring-biased tethering member in a spring-loaded first configuration;

wherein, when the spring-biased tethering member extends out from the distal-most opening of the catheter assembly, the spring-biased tethering member is released to a second configuration in which the spring-biased tethering member holds the cap in an open position, the open position being that at which an entirety of the cap is laterally offset from the distal-most opening; and

wherein, when in the second configuration, the spring-biased tethering member has a pre-formed curvature comprising a plurality of bends, at least two of the plurality of bends in different directions.

12. The subassembly of claim 11, wherein spring-biased tethering member comprises a super-elastic wire having the pre-formed curvature.

13. The subassembly of claim 12, wherein the super-elastic wire of the spring-biased tethering member has a rectangular cross-section.

14. The subassembly of claim 11, wherein the pre-formed curvature comprises a first bend, a second bend closer to the distal end of the spring-biased tethering member than the first bend, and a third bend closer to the distal end of the spring-biased tethering member than the second bend, the first of the three bend extending around approximately 180 degrees, and each of the second and third bends extending around approximately 90 degrees.

15. The subassembly of claim 11, further comprising a radiopaque marker extending around the transition zone of the cap.

16. The subassembly of claim 11, further comprising a radiopaque marker extending within the second portion of the cap.

17. The subassembly of claim 11, further comprising an atraumatic guide-wire tip being coupled to the cap and extending distally from the distal end of the cap.

18. The subassembly of claim 11, wherein the transition zone of the cap defines an edge that abuts a distal terminal end of the catheter assembly when the first portion of the cap is fitted within the distal-most opening of the lumen defined by the catheter assembly.

19. The subassembly of claim 11, wherein the plurality of bends comprises a first bend and a second bend closer to the distal end of the spring-biased tethering member than the first bend, wherein a direction of the second bend is opposite a direction of the first bend.

20. A method for assembling an interventional medical system, the method comprising:

forming a curvature in a super-elastic wire, the curvature comprising a plurality of bends, at least two of the plurality of bends in different directions;

securing the super-elastic wire to a catheter assembly;

coupling the super-elastic wire to a cap so that the formed curvature extends in close proximity to a proximal end of the cap;

loading an implantable medical device into a lumen of the catheter assembly, through a distal-most opening of the catheter assembly; and

positioning a first portion of the cap within the distal-most opening of the catheter assembly, so that the coupled super-elastic wire extends alongside the loaded implantable medical device in the lumen, and a second portion of the cap extends distally from a distal terminal end of the catheter assembly defining the distal-most opening of the catheter assembly.

21. The method of claim 20, wherein securing the super-elastic wire to the catheter assembly comprises threading the super-elastic wire through an inner tubular member of the catheter assembly.

22. The method of claim 20, wherein securing the super-elastic wire to the catheter assembly comprises coupling the wire to an elongate rod and then threading the rod through an inner tubular member of the catheter assembly.