Interventional medical systems, catheters, and subassemblies

Patent metadata

Field	Value
Publication number	US-9844664-B2
Application number	US-201514880371-A
Country	US
Kind code	B2
Filing date	Oct 12, 2015
Priority date	Oct 12, 2015
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

An engagement subassembly of a catheter, for retrieving an implanted medical device, may include at least three segments or, alternately, capture members being spring biased outward from a longitudinal axis of the subassembly, wherein a device receptacle of the catheter forces the capture members/segments, against the spring bias thereof, toward the axis. Each capture member includes a spring-biased wire and a grip, which is located between proximal and distal portions of the corresponding wire, and which is configured to interlock within a gap between a device attachment feature and housing; a length of each wire distal portion may be approximately equal to that of the device housing. An interlocking edge of each segment interlocks within the gap between the attachment feature and housing, when a distal-facing surface of each segment, which tapers outward from the axis in a distal direction, comes into confronting engagement with the device housing.

First claim

We claim:

1. An interventional medical system, comprising:
an implantable medical device, comprising:
a hermetically sealed housing,
an attachment feature joined to a proximal end of the housing and protruding proximally therefrom, and
a fixation member mounted to the distal end of the housing; and

a catheter comprising:
an inner assembly comprising an elongate shaft and an engagement subassembly coupled to a distal end of the inner assembly shaft, and
an outer assembly comprising a shaft, a device receptacle sized to contain the medical device therein joined to a distal end of the outer assembly shaft, the device receptacle being in fluid communication with a lumen of the outer assembly shaft and having a distal-most opening that allows passage of the medical device therethrough, wherein the inner assembly shaft is in sliding engagement with the lumen of the outer assembly shaft, and the engagement subassembly is in sliding engagement with the device receptacle and the engagement subassembly includes at least three capture members formed in a spring-biased outward relationship to a longitudinal axis thereof, wherein each capture member comprises:
an elongate spring-biased wire, and each wire includes a proximal portion and a distal portion,
a grip located between the proximal and distal portions of the corresponding spring-biased wire, the grip being configured to interlock within a gap between the device attachment feature and the proximal end of the device housing, when the device receptacle of the catheter outer assembly forces the capture members, against the spring-bias thereof, toward the longitudinal axis of the engagement subassembly, and
a length of the distal portion of each spring-biased wire being approximately equal to a length of the device housing, each distal portion extending alongside the device housing when the grip of each capture member interlocks within the gap between the device attachment feature and the proximal end of the device housing.

2. The system of claim 1 , wherein the grip of each capture member of the engagement subassembly comprises a polymer component secured to the corresponding spring-biased wire.

3. The system of claim 1 , wherein the grip of each capture member of the engagement subassembly comprises a pre-formed intermediate portion of the spring-biased wire.

4. The system of claim 1 , wherein the engagement subassembly further comprises a flexible polymer loop secured to the distal portion the spring-biased wire of each capture member, the loop defining a distal-most opening into an interior of the engagement subassembly.

5. The system of claim 1 , wherein the engagement subassembly further comprises a pull band and an elongate pull wire coupled thereto, the pull wire extending along a length of the inner assembly shaft, the proximal portion of the spring-biased wire of each capture member being coupled to the pull band, and the pull band being mounted in the distal end of the inner assembly shaft.

6. A catheter for retrieving an implantable medical device from an implant site, the medical device including a housing, the catheter comprising:
an inner assembly comprising an elongate shaft and an engagement subassembly coupled to a distal end of the inner assembly shaft, and
an outer assembly comprising a shaft, a device receptacle sized to contain the medical device therein joined to a distal end of the outer assembly shaft, the device receptacle being in fluid communication with a lumen of the outer assembly shaft and having a distal-most opening that allows passage of the medical device therethrough, wherein the inner assembly shaft is in sliding engagement with the lumen of the outer assembly shaft, and the engagement subassembly is in sliding engagement with the outer assembly receptacle and the engagement subassembly includes at least three capture members formed in a spring biased outward relationship to a longitudinal axis thereof, wherein each capture member comprises:
an elongate spring-biased wire, and each wire includes a proximal portion and a distal portion,
a grip located between the proximal and distal portions of the corresponding spring-biased wire, the grip being configured to interlock within a gap between an attachment feature of the device and a proximal end of the housing of the device, when the device receptacle of the catheter outer assembly forces the capture members, against the spring-bias thereof, toward the longitudinal axis of the engagement subassembly, and
a length of the distal portion of each spring-biased wire being approximately equal to a length of the housing of the device, each distal portion being configured to extend alongside the device housing when the grip of each capture member interlocks within the gap between the device attachment feature and the proximal end of the device housing.

7. The catheter of claim 6 , wherein the grip of each capture member of the engagement subassembly comprises a polymer component secured to the corresponding spring-biased wire.

8. The catheter of claim 6 , wherein the grip of each capture member of the engagement subassembly comprises a pre-formed intermediate portion of the spring-biased wire.

9. The catheter of claim 6 , wherein the engagement subassembly further comprises a flexible polymer loop secured to the distal portion the spring-biased wire of each capture member, the loop defining a distal-most opening into an interior of the engagement subassembly.

10. The catheter of claim 6 , wherein the engagement subassembly further comprises a pull band and an elongate pull wire coupled thereto, for deflection of the inner assembly shaft, the pull wire extending along a length of the inner assembly shaft, the proximal portion of the spring-biased wire of each capture member being coupled to the pull band, and the pull band being mounted in the distal end of the inner assembly shaft.

11. An engagement subassembly for an inner assembly of a catheter for retrieving an implanted medical device having an attachment feature and a housing, and the subassembly comprising:
an inner assembly shaft;
an elongate pull wire extending from a proximal end thereof to distal end thereof over a length approximately equal to a length of the inner assembly shaft;
a pull band coupled to the distal end of the pull wire and configured for mounting in a distal end of the inner assembly shaft for deflection thereof; and
at least three capture members arranged around a longitudinal axis of the engagement subassembly and being spring biased outward from the longitudinal axis, each capture member comprising:
a spring-biased wire including a proximal portion and a distal portion; and
a grip located between the proximal and distal portions of each spring-biased wire, each grip being configured to interlock within a gap between the attachment feature of the medical device and a proximal end of the housing of the medical device, when a device receptacle of an outer assembly of the catheter forces the capture members, against the spring-bias thereof, toward the longitudinal axis of the engagement subassembly.

12. The subassembly of claim 11 , wherein the grip of each capture member comprises a polymer component secured to the corresponding spring-biased wire.

13. The subassembly of claim 11 , wherein the grip of each capture member comprises a pre-formed intermediate portion of the spring-biased wire.

14. The subassembly of claim 11 , wherein the distal portion of each capture member is extendable over a length approximately equal to a length of the housing of the device.

15. The subassembly of claim 11 , further compr

Assignees

• Medtronic Inc

Inventors

• Mcevoy Francis D
• Geraghty Brendan P
• Mcdonnell Paula
• Mchugh Pat
• Meade Colin W
• Ward Sean
• Wood Rónán
• O'Carroll Kealan E
• Kelly Tomas K
• Francis Gwenda

Classifications

• A61B17/22031 Primary

  Gripping instruments, e.g. forceps, for removing or smashing calculi (A61B17/221 takes precedence) · CPC title

• A61N1/3756

  Casings with electrodes thereon, e.g. leadless stimulators · CPC title

• A61B2017/22035

  for retrieving or repositioning foreign objects · CPC title

• A61N1/37205

  Microstimulators, e.g. implantable through a cannula · CPC title

• A61M25/0074

  Dynamic characteristics of the catheter tip, e.g. openable, closable, expandable or deformable · CPC title