Source: https://patents.google.com/patent/US20100286756A1/en
Timestamp: 2019-02-20 06:47:11
Document Index: 780905370

Matched Legal Cases: ['art 40', 'art 40', 'art 40', 'art 40', 'art 40', 'art 40']

US20100286756A1 - Catheter Device - Google Patents
US20100286756A1
US20100286756A1 US11/917,499 US91749906A US2010286756A1 US 20100286756 A1 US20100286756 A1 US 20100286756A1 US 91749906 A US91749906 A US 91749906A US 2010286756 A1 US2010286756 A1 US 2010286756A1
US11/917,499
US8758420B2 (en
2006-06-16 Application filed by CR Bard Inc filed Critical CR Bard Inc
2008-06-19 Assigned to ANGIOMED GMBH & CO. MEDIZINTECHNIK KG reassignment ANGIOMED GMBH & CO. MEDIZINTECHNIK KG ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: DORN, JURGEN, WUEBBELING, MARTIN
2010-11-11 Publication of US20100286756A1 publication Critical patent/US20100286756A1/en
2014-06-24 Publication of US8758420B2 publication Critical patent/US8758420B2/en
A catheter device having a shaft that extends from a proximal end to a distal end to carry on its distal end a self-expanding implant for intraluminal advance on a guidewire and delivery of the implant to an implant site by proximal withdrawal of a sheath that lies radially outside the implant in the catheter, the catheter including a first shaft element to pull the sheath proximally and a second shaft element to push the implant distally to prevent the implant moving proximally with the sheath when the sheath is pulled proximally, wherein the second shaft element carries a stopper for abutting the implant, the stopper comprising proximal and distal portions having different radiopacities.
The present invention is an improvement of the invention disclosed in WO-A-2005/053574.
It is an object of the present invention to improve the visualisation capabilities of the catheter-based implant delivery system to a target implant site in a human or animal body. These visualisation capabilities are particularly important, when the implant is intraluminally advanced along a tortuous path through the system of body vessels, and the medical practitioner needs to ascertain the exact position of the implant. It is another object of the present invention to improve the capability of the delivery system to accurately release the implant at the implant site by proximal withdrawal of the sheath radially surrounding the implant.
In accordance with one aspect of the present invention, a catheter device is provided in which a second shaft element for pushing the implant distally to prevent the implant from moving proximally with a sheath constraining the implant in a radially compressed delivery configuration inside the sheath of the catheter device carries a stopper for abutting the implant. The stopper according to the present invention comprises proximal and distal portions having different radiopacities. As the implant abuts the stopper during proximal withdrawal of the surrounding sheath, visualisation of the position of the stopper, and hence of the implant, is facilitated if the stopper exhibits at its distal and proximal ends different radiopacities which give rise to a contrast on the X-ray image the medical practitioner is viewing when trying to ascertain the position of the implant inside the body vessel. Moreover, visualising the position of the implant by means of the stopper has the advantage that a component of the catheter device itself is used for the visualisation which is not to be crimped down to a reduced diameter profile for delivery, as it is the case when the implant were to be furnished with improved visualisation capabilities.
In accordance with the disclosure of WO-A-2005/053574, the present invention is useful in improving positional placement of a self-expanding stent at a target stenting site in a human or animal body, when using a transluminal, catheter-based stent delivery system. A catheter device of the type identified above is provided, and in which the shaft of the catheter device features a shaft pusher tube with a lumen and with a distal end operatively connected to the stent stopper, the lumen of the pusher tube being occupied by a pull wire or rod which is arranged to pull back the sheath surrounding the self-expanding stent. The wire or rod can itself be tubular. It is resistant to endwise extension of its length, and the pusher tube is resistant to endwise shortening of length when placed in endwise compression. Normally, both so-axial elements will be of a suitable metal such as stainless steel.
Thus, the shaft tube is conveniently a stainless steel or PHYNOX hypotube and the pull wire is conveniently of metal, such as a stainless steel wire, either solid or hollow. While the sheath will very likely be of polymer, it can be made resistant to elastic stretching during proximal withdrawal and release of the stent by embedding within the annular wall thickness of the polymer sheath a fiber reinforcement such as a braided metal mesh. Here, there is effectively a continuous strand of elastic strain-resistant metal in the pulling system, all the way from the proximal end of the pull wire to the distal end of the polymer sheath, again adding to the precision of proximal withdrawal, and minimising any elastic strain within the system during withdrawal.
The pull wire can be connected to the sheath by, for example, first and second metal rings, one inside the other, and sandwiching the sheath so that one of the metal rings is inside the sheath annulus and the other is outside the sheath annulus. The inside metal ring would normally be welded, soldered or brazed to the distal end of the pull wire (adhesives being generally disfavoured in failure-critical applications in such stent delivery devices) while the outer metal ring can be swaged down onto the sheath to press the sheath radially inwardly to a radius less than that of the outer diameter of the inside metal ring.
The present applicant has developed stent delivery systems (see WO2001/34061) which feature a catheter system having a heat-formed tapered distal tip which can help to reduce trauma to the body as the catheter system is advanced in a bodily lumen along its guidewire. Preferably the sheath has a tapered distal tip, which can be heat-formed, and which desirably tapers down to an end orifice which fits relatively closely around the cylindrical outside surface of the guidewire.
For the sake of completeness, and to put the present invention in the context of the prior art documents seen with hindsight to be helpful in appreciating how the present invention contributes to the state of the art, reference will now be made to EP-A-611 556 and WO 96/39998. EP-A-611 556 discloses a rapid exchange balloon catheter stent delivery system in which a sheath is pulled back proximally by a pull wire, to expose a stent mounted on a balloon, so that the stent can then be deployed by inflation of the balloon. The stent is not a self-expanding stent, so is not pressing on the luminal surface of the sheath during advance of the delivery system to bring the stent into the location of stenting. Accordingly, the balloon-expandable stent is not liable to be carried proximally by the sheath when the sheath is pulled proximally. Accordingly, there is no need for a stopper to resist unwanted proximal movement of the stent. Accordingly, there is no significant resistance to proximal movement of the sheath. Accordingly, there is no need for the shaft of the system, defining the lumen in which the pull wire is located, to be resistant to axial compressive stresses. The problem of designing a system to deliver a self-expanding stent which maintains the axial position of the stent correct during stepwise release of the stent is not a problem experienced with balloon-expandable stent delivery systems.
Now to be described is a particular embodiment of the present invention in FIG. 2A which is an improvement of the invention described in WO-A-2005/053574 (WO 574). It is obvious for the skilled person that parts of the disclosure of WO 574 also apply to what is shown in FIG. 2A.
The bands 26 a, 26 b may not necessarily be made of stainless steel. Other materials include polymers, such as PHYNOX™, titanium, shape memory alloys, such as NITINOL™. The use of NITINOL™ may be advantageous in that the crimping down of the sheath to a reduced diameter at the position of the bands may occur upon exposing the catheter to a temperature change, such as by inserting it into the body of a human or an animal. The bands may also be made of radiopaque material so as to serve as marker bands. It is conceivable that the reduced inner diameter portion proximal of the annulus 28 may be provided by a tube heat-shrunk onto the luminal surface 24 of the sheath 14 at the location of the steel band 26B in order to effect reduction of the inner diameter of the sheath.
The pusher-guider tube 42 can have different lengths. Although not shown in FIG. 2A, the pusher-guider tube 42 may extend beyond the distal end of the stent, or it can terminate at the stopper 40 for abutting the stent, as described below, and connected to a polymer tubing distally of the stopper 40. The connection may be established by various means, such as heat-shrinking a sleeve over the connecting portion, overmolding, glueing, etc.
As shown in FIG. 2A, a mechanical interengagement interference fit is provided at the abutting portion of the polymer part 40A and the metal part 40B. The recessed portions of the polymer part 40A and the metal part 40B are not restricted to the shape as shown in FIG. 2A. Other interference fit designs are conceivable so long as dislodging of the polymer part 40A from the metal part 40B is prevented.
The guidewire port is conveniently located away from both ends of the catheter system. possibly about half way along the length, or around 75 cm from the distal tip of the system.
1. A catheter device having a shaft that extends from a proximal end to a distal end to carry on its distal end a self-expanding metal implant for intraluminal advance on a guidewire and delivery of the implant to an implant site by proximal withdrawal of a sheath that lies radially outside the implant in the catheter, the catheter including a first shaft element to pull the sheath proximally and a second shaft element to push the implant distally to prevent the implant moving proximally with the sheath when the sheath is pulled proximally, wherein
the second shaft element carries a stopper with a distal annulus for abutting the proximal end of the implant, the stopper comprising proximal and distal portions having different radiopacities, the distal portion defining the distal annulus and having a radiopacity lower than that of the proximal portion, for contrast with the radiopacity of the metal implant.
2. Catheter as claimed in claim 1, wherein the distal portion and the proximal portion of the stopper are mechanically engaged with one another.
3. Catheter as claimed as claimed in claim 1, wherein the distal portion and the proximal portion each comprise a recessed portion which are engaged with one another by an interference fit.
4. Catheter as claimed in claim 1, wherein the distal portion of the stopper is made of a polymer.
5. Catheter as claimed in claim 4, wherein the polymer portion of the stopper is made of PEEK.
6. Catheter as claimed in claim 1, wherein the proximal portion of the stopper is made of stainless steel.
7. Catheter as claim in claim 4, wherein
the proximal portion of the stopper is made of stainless steel and
the distal polymer portion is partly molded over the proximal stainless portion.
8. Catheter as claimed in claim 1, wherein second shaft element comprises a pusher-guider tube and a pusher tube.
9. Catheter as claimed in claim 8, wherein the pusher tube has a distal end to which is fixed, side-by-side, the proximal end of the pusher-guider tube that defines a lumen for a guidewire.
10. Catheter as claimed in claim 5, wherein
the second shaft element comprises a pusher-guider tube and a pusher tube; and
a stainless steel portion of the stopper is welded to the pusher-guider tube.
11. Catheter as claimed in claim 5, wherein
a stainless steel portion of the stopper is glued to the pusher-guider tube.
12. Catheter as claimed in claim 8, wherein the pusher-guider tube extends distal of the stopper to the distal tip of the catheter.
13. Catheter as claimed in claim 1, including a self-expanding stent.
14. Catheter as claimed in claim 1, wherein the distal portion of the stopper has a distal abutment surface that defines the proximal end of an annular cavity within the catheter that is for receiving the implant to be carried by the catheter.
15. Catheter as claimed in claim 14 that is capable of carrying a range of said implants of different lengths, such capability being provided by exchanging the distal portion of the stopper with another such distal portion of a different length, the aggregate length of the distal portion and implant remaining substantially unchanged.
16. Method of making a system for intraluminal delivering of a self-expanding implant, comprising providing a catheter device that carries the implant on its distal end within a sheath that is withdrawn proximally to release the implant, while a stopper restrains the implant from moving proximally with the sheath
providing the stopper with a proximal portion that is fixed to a shaft component of the catheter device and a distal component with an axial length that can be selected to complement the length of the selected implant, so that an aggregate axial length of the implant and the distal portion remains substantially constant through the selection of implants of various lengths, the distal portion having a proximal-facing abutment surface for abutment with the proximal portion of the stopper and a distal-facing abutment surface for abutment with the implant.
17. Method according to claim 16, including the step of fixing the proximal stopper portion to the shaft component by fused metal.
18. Catheter as claimed as claimed in claim 2, wherein the distal portion and the proximal portion each comprise a recessed portion which are engaged with one another by an interference fit.
US11/917,499 2005-06-16 2006-06-16 Catheter device Active 2031-10-02 US8758420B2 (en)
PCT/EP2006/005805 A-371-Of-International WO2006133958A1 (en) 2005-06-16 2006-06-16 Catheter device
US14/252,667 Continuation US9615950B2 (en) 2005-06-16 2014-04-14 Catheter device
US20100286756A1 true US20100286756A1 (en) 2010-11-11
US8758420B2 US8758420B2 (en) 2014-06-24
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:DORN, JURGEN;WUEBBELING, MARTIN;REEL/FRAME:021117/0963