FR2810876A1 - Surgical apparatus for repairing diseased blood vessels, e.g. aneurysm - Google Patents

Abstract

The apparatus consists of an implant (100') designed to be introduced into the duct being treated, a reinforcing element (140'a) to go round outside of the duct opposite the proximal end (100a) of the implant, and fixings for attaching the reinforcing element to the implant through the duct wall. It also incorporates an instrument (320) for delivering the reinforcing element and the fixings, preferably from outside the duct. The fixings are in the form of staples delivered through an endoscopic stapler.

Description

The invention relates to a medical assembly improving the conditions for putting on

  in place and holding of an implant in an anatomical conduit, in particular if it is an implant, or stent, vascular for aneurysm adapted to be put in place at least in part percutaneous endoluminal route. In the field, we know different types of implants and

different laying techniques.

  Thus, in US-A-5,527,355, there is taught an apparatus and a method for treating aneurysm by applying a strip of lining around the outer surface of the vessel, at the places where the

  spring means for holding the implant against the vessel (stents).

  A certain number of problems nevertheless remain linked to the conditions of attachment of the implant to the wall of the conduit, as well as to the possible conditions of effective sealing to be obtained with respect to the fluid.

  able to circulate there, in particular in the event of treatment of aneurysms.

  Note that in US-A-5,527,355, the system for attaching the band around the duct can pose a problem, in particular if it is the aorta, since it can be particularly delicate to try to make it

completely around.

  Advantageously, the fastening means between the lining and the implant will consist of clamping means for internally pressing the implant against the wall of the duct in question, in a manner substantially impermeable to the fluid flowing therein, and this at least at the upstream end. of the implant, which is preferably provided with a stent The invention has endeavored to define these means of attachment, or even tight tightening, between the lining and the implant. Next an embodiment, these attachment means comprise, or consist of mechanical, electrical or thermal means (in particular, with thermal shape memory, such as in NflINOL) intended to occupy two states: either a first "introduction" state in which they will have a reduced diameter for be implemented from outside the conduit, through the strip to the implant, or a second "fixing" state where they will be radially deployed by presenting an enlarged head to leu rs

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  two opposite ends, proximal and distal, this transition from their first to their second state taking place mechanically, electrically or thermally, with relative approximation of the two ends, in order to ensure a tightening

  the implant against the inner wall of the conduit.

  Thus, the fixing means will then advantageously have a variable length so as to be able to clamp the wall of the conduit between the external lining and the internal implant, with two enlarged fixing zones, at two opposite ends, so as to be linked , at one end to the sealing strip and, at the other end, to the implant If it is a mechanical fastening means, it may

  particular consist of a "rivet" or a staple.

  An even more detailed description of the invention will now be given.

  be provided with reference to the accompanying drawings in which: - Figure 1 shows the implant in place in the aneurysm with the lining strip ready to surround it, - Figure 2 shows a laparoscopic forceps, - Figure 3 shows the placement of the implant and the lining strip, - Figure 4 shows a fixing rivet, - Figure 5 shows the same rivet ready to be implanted, and - Figure 6 shows, in enlarged view, the rivet in place through the conduit In what follows, we only consider the case of an implant consisting of a stent intended to treat an aortic aneurysm, even if other vessels can benefit from the improvements made

by the invention.

  Thus, FIG. 1 shows an aorta V suffering from an aneurysm 110.

  The aneurysm is delimited by an upper (or upstream) collar 112 and a collar

  lower (or downstream) 114. Mark 10 indicates the direction of blood circulation.

  A stent 100, of axis 10Oc, is implanted at least at

the location of the aneurysm.

  The implant 100 can in particular be presented as described in

  US-A-4,533,665, or FR-A-2,732,404.

  The implant is pressed towards its proximal end 100a against the wall P of the vessel V, by means of at least one radially deployable enlarger, usually called "stent", 105. In addition to the stent 105 (which in this case includes three stages of zigzagged metallic wires wound on themselves on each stage), the implant comprises a flexible, synthetic, biocompatible sheath, 108, for example made of Dacron, making it possible to channel blood through it, once

  the implanted prosthesis. The stent is sutured to the sheath in 161.

  The (each) stent 105 is in this case radially "self-expanding" (as in FR-A-2 732 404), although it may, as a variant, be constituted by an openwork metal tube, radially deployable at- beyond its elastic limit under the effect of an internal force of radial expansion, such as a balloon,

as in US-A-4,533,665.

  Around the duct V, and more particularly around the upper collar 112, there appears a part 140 for lining the duct. This is a part which will serve to secure the implant to the vessel at the location of the collar 112, preferably blood-tight. In

  in this case, this piece appears as an elongated strip.

  Once in place, the strip 140 will come to externally and locally double the wall of the vessel to promote the establishment of means for fixing this strip to the implant 100, therefore through the wall of the conduit V, in order to apply internally this implant against the wall P. In FIG. 2, a laparoscopy tool 327 has been shown diagrammatically. It is a tool comprising a distal forceps 329 adapted to be introduced into the patient's body through his skin, by laparoscopy, to

inside a catheter 331.

  The clamp 329 is maneuverable by a proximal telescopic handle 333 adapted to be taken in hand by the practitioner, outside the patient's body. In FIG. 3, the implantation technique of the endoprosthesis 100 is represented schematically, by percutaneous endoluminal route (in

  particular, technique called "SELDINGER").

  More specifically, after practicing a VA access route through the patient's skin; and having introduced a widening catheter (not shown) on the wire guide 210, the outer sheath 230 enclosing a second sheath 240 near the distal end from which the implant 100 has been preloaded beforehand, is introduced, after removal of the 'opener. When it reaches zone 110 of the aneurysm, the implant is

  correctly positioned, radiographically.

  The two sheaths 230, 240 are then successively withdrawn, the internal catheter 250 serving, if necessary, for the rear support of the implant,

  so that it does not move back when the sheaths are removed.

  The implant 100 then deploys radially by itself if it is self-expanding or under the effect of an internal inflation means, if such

  means have been provided, or by any other equivalent means.

  The solution of the invention for fixing the lining to the implant 100 through the wall of the vessel consists in using as means (s) of fixing

  one (or more) clip (s) or rivet (s) marked 335 in FIG. 4.

  it is a metallic part (stainless steel, for example) or plastic, biocompatible, a few millimeters in length and

diameter, once installed.

  This rivet may include a thin flexible rod 337 of length comparable to the length of the insertion sheaths, so that it can be operated from outside the patient's body (for example, length 10 to 15 cm). Towards its distal end, the filament 337 is extended by a series of beads or radial protrusions 339 and ends with legs 341 in conical corolla to be thus housed inside an introducer catheter 345 (see FIG. 5) but susceptible to move away radially. This assembly consisting of a single piece is completed by a slide 347, preferably provided with radial lugs 349 and mounted to slide along the beads 339 which then define notches

axial positioning of the slide.

  The insertion of the rivet 335 takes place by laparoscopy inside

  of the sheath 345 (FIG. 5), to the point where the strip is already in place.

  The protective catheter 345 is then withdrawn and, under the pressure of the internal flexible plunger 337 (see 351, FIG. 5), the clip 335 is then engaged through openings, slots, cutouts or passages of the strip, then through the conduit V and finally, through the implant 100, the tapered head

341 entering first.

  While withdrawing the rod 337 backwards from outside the patient's body, the practitioner then pushes on the plunger 351 to move the slide 347 towards the head 341, until the vessel is sufficiently tightened between the band and the implant Once the slide 347 is jammed and retained in position by one of the notches 339, the pliers 327 can, for example, be used to cut the thin part between two beads 339 located behind the slide, thus giving the clip 335 its appearance in Figure 6. The practitioner can then pull the

rod 337 to remove it.

  After having checked that all the instruments and means

  have been removed, the first tracks are closed.

  As a conduit other than a vascular one on which one could intervene in the context of the invention, mention may be made of the gallbladder (see in this regard WO-A-97/09008, for dimensions, materials, etc., cf. Pages 8 to

11, in particular).

  Also note that as an alternative, the stent 100 could

  be presented as a bifurcated tube, as in US-A-5,527,355.

  Other types of endoluminal implants may also be suitable.

Claims (7)

  1. Medical assembly for fixing through a anatomical conduit (V) a lining (140) and an implant (100) insertable in this conduit (endoprosthesis) for treating a condition of the conduit comprising a fixing means (335), a tool laparoscopy (327), characterized in that it comprises an outer sheath (230) capable of successively containing - a widening catheter inserted on a wire guide (210), - a second sheath (240) near the distal end of which the implant (100) has previously been loaded, the attachment means comprising two enlarged attachment zones   (341,347,349) at two opposite ends, connected together by a link (339).   2. Medical unit according to claim 1, characterized in that the tool (327) comprises a distal forceps (329) adapted to be introduced into the body of the patient to   through her skin, laparoscopically, inside a catheter (331).   3. Medical unit according to claim 1 or 2, characterized in that the clamp   (329) can be operated by a proximal telescopic handle (333).   4. Medical assembly according to claim 1 2 or 3, characterized in that this fixing means comprises a thin flexible rod (337) of length (25) comparable to the length of the insertion sheaths, so that it can be maneuvered since outside the patient's body.   5. Medical assembly according to claim 1, 2, 3 or 4, characterized in that this fixing means comprises a thin flexible rod (337) of length (25) from 10 to cm. 6. Medical unit according to claim 1, 2, 3, 4 or 5, characterized in that the fixing means ending in legs (341) in conical corolla capable of deviating radially is housed inside d an introducer catheter (345).   7. Medical assembly according to claim 6, characterized in that the introducer catheter (345) contains an internal flexible pusher (337, 351), for engaging the fixing means (335) through openings, slots, cutouts or passages of the   strip (140), duct (V) and implant (100).