Abstract:
A tubular catheter for implantation in a tubular structure of a human or animal body, comprising a lumen, characterized in that the catheter comprises a minimum of one radial groove.

Description:
This application claims the priority of Swiss patent application 1239/97, filed May 27, 1997, which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to a catheter to be implanted in a human or animal body in accordance with the preamble of claim 1. 
     SUMMARY 
     Catheters which normally remain in the body for an extended period of time for the introduction of drugs into human or animal blood vessels have been prior art for some time. the said catheters may be implanted in the body through the skin without a connector, thus allowing a single tube supplying a drug from a drug container to the site of release in the body. However, this constitutes a very high risk of infection. Consequently, a subcutaneous or percutaneous port unit is often arranged between a catheter implanted in the body and an infusion tub arranged outside the body, connecting the implanted catheter to the infusion tube. U.S. Pat. No. 5,206,255 describes a subcutaneously implanted port unit and patent specification EP-B-O 302 076 a percutaneously implanted port unit. 
     The arrangement of prior art implanted catheters in a blood vessel may cause tearing of the catheter from the vessel or rubbing of the catheter against the internal wall of the blood vessel or the point of entry of the catheter into a blood vessel unless the patient is restrained from moving. 
     The present invention intends to provide a remedy for this. The invention is based on the task of developing a catheter to be fixed for long-term implantation in a tubular structure of a human or animal body, having a lumen, such as a blood vessel, a lymphatic vessel or an umbilical vein, reducing the risks of being torn out and of infection without limiting a patient&#39;s freedom to move. 
     The invention solves the task by a catheter showing the features of claim 1. 
     The benefits offered by the invention are mainly due to the fact that the design of the catheter will increase the freedom of movement of the patient, while simultaneously reducing any tearing out and infection risks. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred example of the invention has been shown in the figures, where: 
     FIG. 1 is a catheter according to the invention. 
     FIG. 2a is a type of attachment of a catheter according to the invention. 
     FIG. 2b is a preferred type of attachment of a catheter according to the invention. 
     FIG. 3 is a type of coupling of the catheter according to the invention including a housing. 
    
    
     DETAILED DESCRIPTION 
     As shown in FIG. 1, the catheter 1 according to the invention comprises a cylindrical shaft 5, a continuous drug channel 4 provided in the interior of a catheter and an outlet 3. Two radial grooves 2 are arranged towards the outlet 3. From a production engineering point of view, the outlet 3 including the grooves 2 is attached by welding as a single accessory to an existing catheter 1. The external diameter of the outlet section 3 attached by welding should therefore be larger than the remaining tubular section of the catheter 1. 
     FIGS. 2a and 2b show that the catheter 1 is implanted in a tubular structure 10 comprising a lumen. The catheter 1 is inserted into the tubular wall 12 through an artificial opening 11. The tubular structure 10, for instance, is a still functioning blood or lymphatic vessel or a dried-up vessel, such as an umbilical vein. The catheter 1 is inserted into said tubular structure 10, followed by attachment with a biocompatible thread 20. As shown in FIG. 2b, the thread 20 is wrapped around the tubular structure 10 in a radial groove 2 of the catheter 1, thus allowing the thread 20 to press the tubular wall 12 into the radial groove 2. 
     However, the thread 20 may also be only partially wrapped around the tubular wall 12, as shown in FIG. 2a, and the tubular wall 12 may be pierced at a specific point, thus allowing the thread 20 within the tubular structure 10 to pass along the radial groove 2 and the press the tubular wall into the radial groove 2 outside the tubular structure 10. This offers the advantage that the lumen is not sealed. 
     In the embodiment shown, the catheter 1 comprises two radial grooves 2 for reasons of safety. 
     As shown in FIG. 3, the catheter 1 may be connected to a port unit 30 tapered towards the interior of the body. Such port units are used for connection of an infusion tube arranged outside a human or animal body to a catheter 1 located inside a human or animal body. The port unit 30 comprises a hollow cylindrical sleeve 34 and a radial anchoring plate 33 provided on the same. The port unit 30 comprises a first port 31 towards the exterior and a second port 32 towards the body interior. The second port 32 is at the tapered external end of the port unit 30. A sleeve edge 35 is formed by the second port 32 of the port unit. 
     In the preferred embodiment, the catheter 1 comprises a funnel-shaped catheter head 41 at the end opposite the outlet 3, with its base line showing a larger diameter than the second port 32 of the port unit 30. Below the catheter head 41, a radial rib 43 is provided, also having a diameter larger than the second port 32 of the port unit 30. 
     The catheter 1 is connected to the port unit 30, allowing the sleeve edge 35 of the port unit 30 to be located between the radial rib 43 of the catheter 1 and the catheter head 41. The funnel shape of the catheter head 41 allows the catheter head 41 to be wedged on the edge 35, thus eliminating movement of the catheter 1 towards the interior of the body, with the radial rib 43 preventing movement of the catheter 1 in the other direction. 
     In this constellation, the catheter 1 is either designed as a drug catheter or only as a guide catheter. The two types of catheters are different in that a guide catheter does not comprise a continuous drug channel 4 in its interior, but a channel 4 for the guidance of a drug catheter.