Prosthesis (i.e. – artificial body members) – parts thereof – or ai – Arterial prosthesis
Reexamination Certificate
1999-11-22
2001-06-12
Recla, Henry J. (Department: 3731)
Prosthesis (i.e., artificial body members), parts thereof, or ai
Arterial prosthesis
Reexamination Certificate
active
06245098
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a catheter system which is useful as a delivery kit for introducing objects into the living body.
BACKGROUND
Catheter systems of this type are often used to introduce endoprostheses into the human body in order to place and implant these there. In this sense, endoprostheses are typically stents, traps (filters) or coils (spools). The kits used to introduce these objects generally consist of a catheter (shaft) assembly and a handle part, whereby the handle part is constructed on the one hand to exercise the compressive force which necessarily occurs with the introduction of the kit tip into the body through the circulation system or other very narrow body vessels and, on the other hand, to promote depositing or placement accuracy. In this connection, endoprostheses are firmly anchored on the catheter and are simultaneously introduced into the body therewith. In order to reach the placement site in a targeted manner, these guide catheters must be highly flexible and able to withstand compression at the same time. In order to be able to exactly determine at which place in the body the endoprostheses are deposited, radiopaque markers are in general fixed in the distal end region of the catheter, neighboring the endoprostheses. With trans-illumination of the body, for example by means of x-ray irradiation, these markers remain visible such that the endoprostheses can also be located relative to the body, provided that they do not change their position relative to the markers and the markers do not change their position relative to the catheter.
Therefore, catheter systems as a part of a delivery kit have been proposed in which the markers are ring-like accessory components which are adhered to an inner catheter. Cyanoacrylate compounds are frequently used as an adhesive. They have the advantage that they cure particularly quickly and are suitable for narrow adhesion gaps. In general, however, adhesive compounds have the disadvantage that the cured adhesive negatively influences the mobility or flexibility of the catheter at the region of adhesion. The cured adhesives which are often glass-hard are in their flexibility greatly in contrast to the flexible catheter materials. Thus, stress peaks and fractures of the catheter material can arise at the adhered regions. As a consequence, curing disadvantageously influences the mobility of the kit tip. When the delivery kit is then introduced into the body under increased application of force and the catheter tip is necessarily forced around a diversion or bend, the flexibility required for this exceeds the actual flexibility which is limited by the adhesives. Mechanical failure of the catheter results. This mechanical failure mostly occurs in the form of kinks such that further introduction of the catheter is made impossible. Furthermore, removal by suction through the lumen formed by the inner catheter is made impossible by the kink. It is also possible that mechanical failure occurs in the form of fractures so that not only the further introduction of the catheter is no longer possible, but also sharp-edged fractures possibly injure the body vessels and detached fragments can be washed away by e.g. blood and remain in the human organism.
SUMMARY OF THE INVENTION
Therefore, the object of the present invention is to provide a catheter system that has very high flexibility with simultaneous kink resistance, via which compressive and tensile forces are reliably transferable, and on which accessory components, such as irradiation impermeable and radiopaque markers or endoprostheses, do not change their position relative to the catheter tip and relative to each other during the introduction process. Furthermore, an object of the present invention is to provide a catheter system with which, even in case of mechanical failure in the form of fracture, fragments are reliably removable from the body without injuring the human body upon fracture or upon removal of the broken catheter.
These objects are advantageously solved by a catheter system with at least one longitudinally extending inner catheter and at least one accessory component which is arranged in the distal end region of the inner catheter around the inner catheter, wherein the catheter system further comprises a tightly fitted tubular element on the inner catheter with at least one end-face, wherein the end-face abuts on at least one section of the accessory component in such a manner that movement of the accessory component relative to the longitudinal extent of the inner catheter is prevented. The tubular element is in tension around the inner catheter. Components such as radiopaque markers, stents, filters, coils, endoscopic tools or the like are to be understood as accessory components within the meaning of this solution of the underlying problem according to the invention. The distal end region of the inner catheter denotes the region of the inner catheter which is facing the body interior. By tightly affixing a tubular element on the inner catheter, movement of the accessory components on the inner catheter is prevented by abutting the accessory component or the accessory components to the end-face or end-faces of the tubular element. Furthermore, a total peripheral spanning of the inner catheter is obtained whereby additionally tensions occurring with deviations of the catheter can be partially taken up by the tubular element and as a consequence the inner catheter is relieved. The form locking effect by abutment on the end-face prevents relative movement between accessory component and tubular element. Since the tubular element is additionally tightly fitted on the inner catheter, the relative movement between the accessory component, or, optionally accessory components, and the inner catheter is also advantageously excluded. Correspondingly, the distal end region of the inner catheter is flawlessly identifiable and the location of the object to be introduced is clearly determined in an advantageous manner with customary diagnosis methods, such as ultrasound or x-ray irradiation for example. Through the abutment of the end-face on at least a portion of the accessory component or accessory components, it is ensured that this end-face of the accessory component or components can simultaneously serve as an abutment surface for further components. Additionally, by providing a tubular element, it is also insured that the fragments arising by fracture of the catheter system are held back and are then hampered from spreading into the organism.
The invention is based on the concept of providing a delivery kit with a catheter system in which the accessory components that are necessarily found on the catheter cannot move in their position relative to the center-line of the catheter, but at the same time, upon deformation of the inner catheter, microscopic relative movements between these components and the inner catheter are enabled. Thus, possible kinks are prevented.
According to an advantageous embodiment, the end-face and/or end-faces is (are) substantially formed at a right-angle to the longitudinal extent of the inner catheter. This advantageous further embodiment of the inventive catheter system ensures definitive abutment surfaces which are particularly simple to form and furthermore additionally ensures that an installation direction does not have to be taken into account when mounting the catheter system. Mounting is simplified therewith.
According to another preferred embodiment of the present invention, affixing of the tubular element to the inner catheter occurs by melting. Melting of the tubular element insures an attachment between the element and the inner catheter which is equal to a adhesive bond in its attachment force, whereby neither hardening of the adhesive nor an enbrittlement of the material to be adhered occurs.
Affixing the tubular element by shrinking to the inner catheter is also provided. This fastening mechanism insures similar adhesion conditions, but simplifies the control of the process parameters when mo
Feeser Jörg
Supper Wolfgang
Bui Vy Q.
C. R. Bard Inc.
Morrison & Foerster / LLP
Recla Henry J.
Wight Todd W.
LandOfFree
Catheter system with high kink resistance does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Catheter system with high kink resistance, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catheter system with high kink resistance will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2514693