JPH0575420B2 - - Google Patents

Description

Claim 1: A substantially tubular radially expandable prosthesis 2 and a device for maintaining said prosthesis 2 in a radially contracted state and releasing said prosthesis 2 at a desired position. 200 in combination with a flexible probe 1 disposed coaxially with the prosthesis 2 by inserting the prosthesis 2 into a difficult to access position. The device for retaining and releasing the organ 2 comprises a hose 5 coaxially surrounding the probe 1, one end of the hose 5 being connected to the probe 1 and connecting the hose 5 inside itself. is folded back to form double-walled portions 51, 52 radially surrounding the prosthesis 2, and the prosthesis is releasable by relative movement of both ends of the hose 5 in the axial direction. Apparatus for implanting a substantially tubular radially expandable prosthesis 2.

2. Implantation device according to claim 1, characterized in that one end face 70 of the probe and the double-walled hose parts 51, 52 form a recess 57 in which the prosthesis 2 is accommodated during insertion.

3 said hose is leak-tight, both ends of said hose are tightly connected to probe 1 and the surface of probe 1 adjacent to said hose is leak-tight between the end connections of said hose; whereby the hose and the probe form a chamber 25 and means 14, 22 are provided for pressurizing the fluid in the chamber 25, so that the fluid flows between the hose walls of the double-walled portions 51, 52. Claim 1 characterized in that it reduces the contact pressure and thereby reduces the friction between the hose walls 51, 52 when the outer hose wall 52 and the inner hose wall 51 move relative to each other in the axial direction. 1st term or 2nd term
The implantation device according to any one of paragraphs.

4. The hose turn-up portion 6 of the double-walled hose portions 51, 52 is located in front of the location where one end 7 of said hose is connected to the probe 1 when viewed in the insertion direction 23 of the implantation device into the lumen. the prosthesis 2 by pulling the other end of the hose.
can be released, said hose folded part 6
4. Implantation device according to any one of claims 1 to 3, characterized in that the device moves along the prosthesis (2) towards the hose connection position.

5. When the hose fold 6 of the double-walled hose portions 51, 52 is viewed in the insertion direction 23 into the lumen of the implantation device, one end 7 of said hose is connected to the probe 1.
located rearward of the position connected to the hose, so that the prosthesis 2 can be released by pulling the other end of the hose, and said hose turn-up 6 extends along the prosthesis 2 to the position connected to the hose. The first claim characterized in that it moves towards
The implantation device according to any one of Items 1 to 3.

6. The probe 1 has a bush 55 coaxially surrounding the probe at its front end, the inner wall 51 of the double-walled hose section is fastened to the bush 55, and the bush 55 is attached to the probe 1. The bush 55 is movable axially relative to the lumen, and when viewed in the direction 23 of insertion into the lumen of the implantation device, said bush 55 defines at its front end a recess 57 for receiving the end of the prosthesis 2 during insertion. the flange 60 is attached to the probe 1 and the recess 57
is adapted to form a shoulder for the end of the prosthesis 2 placed in the bush 5 so that when the other end of the hose is retracted the bush 5
6. Implantation device according to any one of claims 1 to 5, characterized in that the surround 56 of the recess 5 and the recess 57 is retracted from the prosthesis 2.

7. Implantation device according to any one of claims 1 to 6, characterized in that the probe 1 has at least one axially passing channel 4.

8. The method according to claims 1 to 7, characterized in that the other end of the hose 5 is tightly connected to the probe 1 by a sealing device 10, 12 movable in the axial direction relative to the probe 1. The implantation device according to any one of the items.

9 Apply the lubricant to the inner double wall portion 51 of the hose 5,
9. Implantation device according to any one of claims 1 to 8, characterized in that it is distributed within 52.

10. Any one of claims 1 to 9, characterized in that the outer wall of the double-walled portion can be inflated to ensure expansion of the lumen of the tubular organ before implantation of the prosthesis. The implantation device according to item 1.

11. Claims 1 to 1, comprising an inflatable balloon device placed in front of the double-walled portion for expanding the lumen of the tubular organ prior to implantation of the prosthesis. 9. The implantation device according to any one of Item 9.

12 an inflatable balloon device disposed around and in a space approximately coextensive with the double-walled portion, said balloon device expanding the lumen of the tubular organ prior to implantation of the prosthesis; 10. Implantation device according to any one of claims 1 to 9, characterized in that it is preferably independently operable in order to perform the implantation.

13. Claims 1 to 1, characterized in that the device comprises an inflatable balloon device placed behind the double-walled portion for expanding the lumen of the tubular organ prior to implantation of the prosthesis. 9. The implantation device according to any one of Item 9.

14 the prosthesis comprises a flexible tubular body;
The tubular body is comprised of several individual rigid yet flexible wire elements each extending helically about the centerline of the tubular body as a common axis and further wound in the same direction; Moreover, it is characterized in that it comprises a plurality of elements that move relative to each other in the axial direction, and the plurality of elements similarly move relative to each other in the axial direction, and intersect with a plurality of elements that are wound in opposite directions. The implantation device according to any one of claims 1 to 13.

TECHNICAL FIELD The present invention relates to a substantially tubular expandable and preferably self-fixating implant, such as a device for implanting a graft, ie, a prosthesis, into a lumen.

BACKGROUND Devices of the type described above for inserting expandable prostheses into, for example, blood vessels or other narrow ducts, have significant deficiencies. One such defect is that the grasping device damages blood vessels when the grasping device surrounding the prosthesis is expanded during insertion to release the prosthesis. In that case, if the gripping device is of the ejector type, friction between the prosthesis and the gripping device can make removal of the prosthesis difficult or even damage it, for example. If the prosthesis were to compress radially during insertion and expand upon release, the friction would be even stronger. The use of lubricants in direct contact with the walls of a prosthesis or conduit to reduce friction may be inconvenient under many environmental conditions. Problems often arise because of the space required for the gripping device, and the often complex nature of the gripping device and its operating elements are accompanied by the risk of malfunctions.

The above-mentioned inconveniences are particularly pronounced when so-called implanted tissue prostheses are implanted into veins, arteries or similar organs. Expandable prostheses are e.g.
Refers to a tubular device forming a prosthesis for an artery, vein or similar organ, the prosthesis being inserted in a radially compressed state and being radially expanded at the site of implantation.

One object of the invention is to provide a device of the type mentioned, which obviates or eliminates the above-mentioned inconveniences, at least to some extent, and which has corresponding advantages over known devices.

Another advantage of the present invention is to provide a device that allows intraluminal implantation of small diameter expandable prostheses that can be implanted by percutaneous insertion.

Yet another object of the invention is to provide a device with a balloon device that can be inflated to widen the lumen prior to implantation of the prosthesis.

Still further objects and advantages of the device of the invention are:
It will be clear to those skilled in the art from the following description.

Features of the Invention The present invention provides a particularly useful device for endoluminally implanting an expandable, self-fixating prosthesis. The device of the present invention comprises such a prosthesis and a device concentric to the prosthesis with a device for maintaining the prosthesis in a radially contracted state and releasing the prosthesis at a desired location in the lumen. a flexible probe disposed in combination with the prosthesis, the apparatus for maintaining and releasing the prosthesis comprising a flexible hose surrounding the probe, one end of the hose surrounding the probe; connected to a probe and with an inner portion of said hose folded back to form a double-walled portion radially surrounding said prosthesis and preferably substantially coextensive with said prosthesis; The device is characterized in that the prosthesis can be released by relative movement of the parts in the axial direction.

Preferably, said one end of the hose is the end of the inner wall of the double-walled hose section when viewed in the radial direction. With this configuration, the hose is unwound from the prosthesis so that no friction occurs between the prosthesis and the hose during the release operation.

The prosthesis is generally tubular and arranged to radially surround the probe, with a double-walled hose section surrounding the prosthesis upon insertion. The probe serves the purpose of guiding the prosthesis during the insertion procedure. preferably flexible and suitable materials;
For example, the probe, which may be constructed of a polymer, may have a channel extending axially therethrough, through which a fluid, for example an imaging liquid, may be introduced into the region in the region of the front end of the probe. can.

The double-walled hose section is therefore adapted to radially enclose the prosthesis. Preferably, the hose has a flexible surface and is manufactured from a pliable material.

Preferably, at least the part of the hose adapted to form a double-walled hose part consists of polyethylene or polyvinyl chloride.

The double-walled hose section is thus adapted to hold the radially compressible prosthesis in a contracted state during insertion, and upon release, the prosthesis expands to its normal size. The inner wall of the cavity is engaged with the inner wall of the cavity.

One end face of the probe and the double-walled hose portion can be configured to form a recess in which the prosthesis is housed during insertion of the prosthesis.

According to a preferred aspect of the device of the invention, the hose is constructed in a leak-tight construction, both ends of the hose are connected to the probe, and the surface of the probe adjacent to the hose between the end connections of the hose is leak-tight. is applied so that the hose and probe form one chamber. A lubricant can be introduced inside this chamber, in particular in the part of the hose forming the double-walled hose part, so that during insertion of the object, i.e. the prosthesis, the lubricant is Reduces friction between the inner and outer walls. The lubricant is therefore sealed inside this chamber and does not exit into the prosthesis or into the space into which it is opened. The difficult-to-access areas are the lumen of the living body,
Lubricating within the chamber, such as by a selected location in a vein, artery, or similar lumen, and without the risk of such lubricant leaking out of the chamber and exposing the implantation site. Instead of the agent, a fluid, for example a blood substitute or a physiological saline solution, can be introduced and pressurized so that said fluid reduces the contact pressure between the inner and outer walls of the double-walled hose section. , thereby reducing friction between the inner wall and the outer wall when the inner and outer walls move relative to each other in the axial direction.
The folded portion of the hose is located in front of the position where the one end of the hose is connected to the probe when viewed in the insertion direction of the probe, so that the other end of the hose cannot be pulled toward the probe. When the prosthesis is thereby released, the folded portion of the hose is moved towards the hose connection position.

At its insertion end, the probe can be provided with a bush coaxially surrounding the probe, to which the inner wall of the double-walled hose section is fastened. This bushing can be axially displaced relative to the probe and can have a recess at its front end when viewed in the direction of insertion of the probe. This recess receives the end of the prosthesis during insertion. A flange attached to the probe is adapted to form a shoulder for the end of the implant placed within the recess;
The bush and recess enclosure are thereby retracted from the prosthesis when the other end of the hose is retracted. The bush and flange thereby form an ejector device that is actuated at the end of the release operation. Preferably, the walls of the recess facing radially to the prosthesis are constructed of a material that has low friction against the prosthesis, for example Teflon. The hose is preferably fastened to the bushing at both ends thereof, whereby said one end of the hose is preferably tightly connected to the probe. Preferably, the hose is fastened to the bushing after the front edge of the bushing when viewed in the direction of insertion of the probe. Thereby, the folded portion of the hose is retracted into a position behind the front edge of the recess before further traction on the hose moves the bush back out of the prosthesis. The other end of the hose is preferably tightly connected to the probe via a sealing device arranged for axial movement relative to the probe.

The front end of the probe can carry a rounded ball that forms the probe head and facilitates insertion of the probe into the desired location. This ball can have a passage connected to the channel of the probe. The diameter of this ball will be approximately the same as the outside diameter of the double-walled hose section surrounding the prosthesis. The ball can be made of metal to facilitate detection of the front end of the probe by X-rays during insertion.

The hose can be flipped over so that the inside is on the outside to form a double-walled hose section surrounding the probe.

The hose can have a length of enlarged diameter forming the radially outer wall of the double-walled hose section.

The folded portion of the hose that joins the walls of the double-walled hose section has an annular prosthesis that faces the insertion end of the probe when moving the other end of the hose in a direction away from the insertion end of the probe. The end of the organ can be exposed last.

In the latter case, the other end of the hose can be held fixed and the probe pushed forward in its insertion direction when releasing the prosthesis. The prosthesis is fixed in solid direction around the probe during the release operation.

In these cases, the scanning person should hold the probe stationary during prosthesis opening when the folded portion of the hose that joins the walls of the double-walled hose section is directed forward in the direction of probe insertion. ,
And the other end of the hose can be towed. The prosthesis is fixed axially around the probe during the release operation.

As previously mentioned in this specification, the device according to the invention can be equipped with an inflatable balloon device for dilating the lumen prior to implantation of the prosthesis. Such balloon devices may be constructed with a double-walled portion of the outer wall that, when inflated, ensures expansion prior to implantation.

According to another aspect of the invention, an inflatable balloon device is provided in front of a double-walled portion for desired dilation of an annular organ, such as a blood vessel, prior to release of the prosthesis at the desired site. Or it can be placed behind the double wall section.

According to yet another aspect of the invention, the inflatable balloon device can be disposed about and substantially coextensive with the double wall section.

The present invention also provides a method of implanting a generally tubular expandable self-fixating prosthesis into a lumen, comprising: (a) a flexible elongated probe, preferably at one end of and around said probe; The prosthesis is placed in a radially contracted state around the probe within a double-walled portion of a flexible hose that is approximately coextensive with the probe (where the double-walled portion of the hose (b) tubing the prosthesis, probe and hose assembly to the desired location within the lumen; (c) releasing the prosthesis at the position by moving the other end of the hose axially relative to the probe to radially expand the prosthesis at the position; and (d) removing the probe and hose, leaving the prosthesis in the intraluminal position.

In such methods for implantation through a lumen, such as in the case of stenosis, the lumen can be widened at the location before releasing and implanting the prosthesis at the location, thereby The prosthesis can act as a stent to prevent reintroduction of the stenosis.

According to one preferred embodiment of the invention, the method of luminal implantation is performed percutaneously.

Embodiments of the claimed invention shown in the accompanying drawings will be described in detail below.
These examples are not intended to limit the invention.

1 is an illustrative axial sectional view of the device according to the invention; FIG. 2 is a longitudinal sectional view of a further improved front part of the device according to the invention in a first operating position;
2 is a longitudinal sectional view of the device of FIG. 2 in a second operating position; FIG. 4 is a longitudinal sectional view of a variant of the device according to the invention;
FIG. 5 is a longitudinal sectional view of another variant of the device according to the invention;
6 shows the device of FIG. 5 in one operating position, FIG. 7 shows an alternative configuration of the device of FIG. 6, and FIG. 8 shows a side view of another embodiment of the device of the invention. 9 is a side view showing still another aspect of the present invention, FIG. 10 is a side view showing still another aspect of the present invention, and FIG. 11 is a side view of FIG. 10 taken along line A-A. It is a cut sectional view.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a device for implanting a so-called expandable implant, i.e. a prosthesis 2, into a difficult-to-access location in a living body, for example at a desired site in a vein or artery. The graft 2 is adapted to reinforce the defective part of the vein or artery.

The device generally includes a probe means 100 having means 200 for grasping and carrying the implant, ie the prosthesis 2, at its insertion end.

The device comprises an elongated flexible probe 1 having a channel 4, preferably extending axially therethrough. The tube/probe 1 is flexible and made of nylon, for example. The tube 1 is provided with a rounded head 3 at its front end. The channel 4 extends through the round head 3. The head 3 serves to facilitate the insertion of the implantation device into a narrow channel. The end 7 of the hose 5 is tightly and fixedly attached to the outer surface of the tube 1. The hose 5, which is flexible and consists of polyethylene for example, is folded inwards to form a double-walled hose section, the inner wall section of which, viewed from the radial direction, encompasses said hose end 7. . The graft 2 is a tubularly arranged radially compressible element surrounding the outer end of the tube 1 and is surrounded by the double-walled portions 51, 52 of the hose 5. hose 5
by retracting the other end (to the right with respect to the tube 1 in FIG. 7. Move toward the installation location. Thereby, no sliding movement occurs between the transplanted tissue 2 and the hose wall 51. While moving the folded part 6 to the right in FIG. 1,
The graft 2 is exposed axially and can expand to engage the inner surface 13 of the vein or artery (see FIG. 2). The other end of the hose 5 is
It is fastened to the outer surface of tube 1. hose 5
are coaxially connected to a flexible operating tube consisting of a stainless steel coil spring 8. The outer surface of the helical spring 8 is covered by a removable tight-fitting casing made of, for example, polyvinyl chloride. A PVC (polyvinyl chloride) surrounding member is tightly connected to the polyethylene tube by means of a joint 15. The bush 10 surrounds the tube 1 and is firmly connected to the spring 8 and fastened to the surrounding member 9. The other end of the bush 10 seals the outer surface of the tube 1.
It has a ring seal 12. Tube 1, hose 5, spring surrounding member 9, bush 10 and O
The ring seal 12 thus closes the closed chamber 25.
is formed. Bush 10 has a hole 14 extending through the wall of the bush and forming a channel. Through this hole 14, a fluid 22, for example a saline solution, a blood substitute, air or a similar fluid, can be introduced and pressurized into the chamber or space 25. Thereby, the fluid 22 can penetrate between the hose walls 51, 52 and separate the hose walls 51, 52, thereby moving the hose walls 51, 52 along the axis with substantially reduced friction. It can be moved relative to the direction.

Channel 4 of tube 1 contains contrast fluid 21
can be used to introduce the implant into the area around the anterior end of the implant, so that the position of the implant can be easily detected using, for example, X-rays.

To release the graft 2, the operator holds the rear end of the tube 1 with one hand and uses the other hand to pull the bush 10 in the direction of the arrow 20 to release the folded portion 6 of the hose 5. can be retracted to release the implant 2.

In FIG. 1, the direction of insertion of the implant device is indicated by arrow 23.

If the graft 2 consists of a graft of the type with a tubular sleeve with a helical reinforcing wire (wire), when the posterior end of the graft 2 is released, the end of the reinforcing wire will be attached to the graft. There is almost no risk of making a hole in the hose 5 at the rear end of the hose 2. In order to eliminate the possibility of this happening, a further improved device of the invention is proposed, which is designed as is clear from FIGS. 2 and 3.

In FIGS. 2 and 3, components corresponding to those of the device in FIG. 1 are given the same reference numerals.

The tube 1 is provided with an annular flange 60 at its front portion. The flange 60 is the tube 1
It has a boss 61 fixedly connected to the outer surface of.
The bush 55 surrounds the boss 61 and the flange 6
The axial movement relative to 0 is controlled by a boss 61. The flange 60 constitutes a stop for the bush 55 in the insertion direction 23 of the implantation device. At its front end, the bushing 55 has a tube section 5 made of a low-friction material, preferably TEFLON, fixedly connected in the direction of the implant 2.
6. When the bushing 55 is in its anterior position (FIG. 2), the tube portion 56 and the flange 60 form a recess 57 for receiving the radially compressed posterior end of the implant 2. The inner wall 51 of the double-walled hose section is fastened around the bush 55. This fastening device is attached to the button 5.
It consists of a circumferential recess 54 formed in the outer wall of 5. A surrounding coupling member 53 clamps the wall 51 of the hose 5 into the recess 54 . When the hose 5 is retracted and moves the folded section 6 to the right, the folded section 6 moves over the tube section 56,
Then, it moves to the circumferential recess 54 of the bush 55. Continued retraction of the hose 5 then retracts the bushing 55 and thereby retracts the Teflon tubing section 56 against the flange 60, exposing the posterior end of the graft 2; It becomes possible to expand the hose 5 in the radial direction without the risk of puncturing it.

FIG. 4 illustrates the front end of another device according to the invention. The device includes a flexible elongated probe 1 coaxially surrounded by a hose 5. One end 7 of the hose 5 is fixed and tied to the outer surface of the probe 1. The hose 5 has double-walled hose portions 51 and 52 that are folded back inward and extend in front of the front end surface 70 of the probe 1.
form. End face 70 and double walled hose section 5
1 and 52 form a recess in which the transplanted tissue 2 is accommodated. The graft 2 is released by retracting the other end of the hose 5 (to the right in FIG. 4).

5 and 6 show an example of an apparatus in which components corresponding to those in FIGS. 1 to 4 are given the same reference numerals. Furthermore, FIG. 5 shows the hose 5
It is shown that it has a portion 50 of a predetermined length formed with a large diameter. a double-walled portion 5 in which the hose 5 is folded inward to surround the tubular graft 2;
1, 52, a hose section with a larger diameter is formed as the outer wall 52 of the double-walled hose sections 51, 52 (FIG. 6).

By arranging the hose 5 in this way,
There is no need for radial expansion to accommodate the implant 2 between the double-walled hose parts 51, 52 and the hose part surrounding the probe 1 and arranged radially inside thereof.

In FIGS. 5 and 6, the front end of the hose 5 is shown fixedly connected to the front end of the probe 1 as shown at 7, and the folded portion 6 of the hose 5 is connected to the front end of the probe 1. When viewed from the insertion direction 23, the folded portion 6 is located behind the coupling position 7 so that when releasing the implant 2 by pulling the other end of the hose 5 against the probe 1, the folded part 6 is located at said position. It is starting to move away from the sky.

In FIG. 1, the implant 2 is shown in direct engagement with the probe 1, whereas in FIGS. It surrounds.

Turn-up section 1 between hose sections 58 and 51
6 is normally kept relatively stationary relative to the probe 1, so that the folded portion 16
It can be said that the front end of the hose 5 functionally constitutes the position where it is connected to the probe 1.

In FIG.
2 is shown.

However, it should be noted that the hose sections 51, 52 can be reversed so that the folded section 6 faces away from the front end of the probe 1, as shown in FIG. In this case,
The implant 2 can be released starting from the posterior end of the implant. This possibility is e.g.
This is important when the graft is implanted into an artery with blood flowing in a direction opposite to the direction of probe insertion.

In this way, the danger present in the device according to FIG. 6, in which the end of the graft tissue that is initially exposed and expanded is at the point where it is folded back by the flow of blood, will be avoided.

It is usually preferable to keep the implant stationary relative to the surrounding portion during the release operation. For example, in the arrangement according to FIGS. 1 and 6,
This condition can be obtained by keeping the probe 1 stationary relative to the surrounding parts and retracting the rear end of the hose during the release operation.

In the arrangement according to FIG. 7, the conditions are such that the rear end of the hose is held stationary and the probe
This can be achieved by moving forward in the direction of insertion.

In FIG. 5, channel 4 of probe 1
The rear end of the probe 1 is shown mounted in a housing 80 having a chamber 81 in communication with the housing.
A channel 84 extends through the wall of the housing 80 and communicates with the chamber 81 to allow the introduction of the fluid 21 into the region of the front end of the probe 1 .

Housing 80 further has an opening with an O-ring type seal 82.

A rod 30 extends through the channel 4 of the probe 1, the chamber 81 of the housing 80 and the O-ring seal 82. The rod 30 has an O-ring seal 8
It is closely surrounded by 2. The front end portion 31 of the rod 30 is curved upward by approximately half a turn with a radius of curvature approximately corresponding to the diameter of the probe 1, for example.

The rod 30 is preferably elastic so that its front end portion 31 can bend the front portion of the probe 1 during probe insertion. In this regard, by retracting the rod 30, the front end portion 3
1 can be drawn into the front part of the probe 1 while bending the front part of the probe 1 according to the combined effect of the elastic resistance to bending of the probe 1 and the terminal part 31. The degree of curvature of the front part of the probe 1 can be varied by rotating the rod 30, and the deflection angle of the front part of the probe 1 is determined by the bending angle of the front part of the probe 1 as the rod 30 is retracted into the probe 1. The selection can be made by changing the length of the song portion 31.

Figures 8-11 of the accompanying drawings show an expandable implant, i.e., a supportive implant that, in addition to features that allow implantation of a prosthesis, serves as a stent to prevent recurrence of the stenosis. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Aspects of the present device also include means for dilating a stenosis within a blood vessel, ie, a lumen, prior to implantation.

FIG. 8 is a diagrammatic side view of such an embodiment of the apparatus of the invention. This device consists of double-walled parts 51,5
It has a central tube 123 surrounded by a flexible hose 5 containing 2 tubes. The radially compressed implant 2 has a double-walled portion 51, as described above.
52 and surrounding the central tube 123.

An expansion balloon 125 is disposed at the front end of the central tube 123, with both ends sealingly attached to the central tube 123.

Although not shown in detail in the drawing, the balloon 125
can be pressurized separately from the double-walled sections 51, 52 by pressurizing the passageway 127 of the central tube 123. The double-walled parts 51, 52 can be pressurized by introducing a pressure medium into the annular space 129 formed between the central tube 123 and the hose 5 surrounding it.

In operation, the apparatus shown in FIG. 8 functions, briefly, as follows.

After the device, generally designated 120, is inserted into a desired location, for example in a blood vessel, balloon 125 is inflated by separate pressurization. The purpose of inflating this balloon 125 is to widen the lumen at the stenotic position where the transplant tissue 2 will be transplanted later.

After dilating the lumen at the desired location, the balloon 125 is deflated and the device 120 is moved forward so that the double walled portions 51, 52 are properly positioned within the blood vessel. By axially moving the central tube 123 and the hose 5 relative to each other, the graft 2 can be released at a desired location within the blood vessel to permanently reinforce the blood vessel and thereby avoid, for example, stenosis recurrence. After implantation, device 120 is removed from the blood vessel.

The device shown in FIG. 9 performs the same function as the device in FIG. 8, but the dilation balloon 143 is placed behind the double walled sections 51,52. In this embodiment, the double-walled portions 51, 52 are inflated using the same pressure medium used to inflate balloon 143 since there is a communication passage between them and balloon 123 to avoid friction. The function of the device of FIG. 9 is otherwise the same as that of the device of FIG. 8, and the same advantages are obtained.

In FIG. 10, a balloon 163 is shown arranged to surround the double wall portions 51, 52. This embodiment, designated 160, includes a central wire, or wire 167, surrounded by a hose 165. A balloon 163 is arranged to surround the hose 165 and
65 and the front portion of the outer wall 52 in a sealed manner.

In order to separately pressurize the balloon 163 and the double-walled portions 51, 52, two inner passages 169, 171 are provided within the hose 165, as shown in an enlarged cross-sectional view in FIG. There is. Passage 169 may be used to accommodate centerline 167 and pressurize double walled portions 51, 52 to reduce friction. The passage 171 has a double wall section 5
1 and 52 can be used to pressurize the expansion balloon 163. Of course, it is also possible to arrange three internal passages inside the hose 165, two of which are used for individual pressurization and the remaining passage is used for the central guidewire.

The function of the device shown in FIG. 10 is that the balloon 163 is used because the position where the lumen is expanded is juxtaposed to the transplanted tissue, ie, the prosthesis 2, housed inside the double-walled portions 51 and 52. The function of the device is the same as that shown in FIGS. 8 and 9, except that no axial movement of the device is required after opening the lumen.

Although specific examples of devices according to the invention have been described above, it should be noted that the illustrated examples may be modified. Therefore, the fluid 22 in the space 25
In order to reduce the friction between the walls 51, 52 of the double-walled hose section, lubricant is introduced into the chamber 25, in particular in the area between the walls 51, 52. can be distributed.

Referring to FIG. 1, if the hose 5 or the traction device attached to it extends into the region of the rear end of the probe 1, the traction movement of the hose 5 can be controlled from an accessible position. For example, component parts 8, 9, 10, 1
It should further be noted that 1, 12, 14, 15 can be omitted. Moshi Hose 5
The walls 51, 52 of the double-walled hose part are made of a material that has low friction against itself.
The distribution of lubricant or pressurization with fluid into the space between can optionally be omitted.

The present invention provides a radially expandable, self-fixating prosthesis, a novel and highly versatile device for implanting graft tissue. This new device makes it possible to implant grafts of almost any diameter, ranging from as small as 1 mm or a few mm to several centimeters in diameter. The design of the device of the invention provides, in particular, in addition to the known balloon dilatation feature, a so-called percutaneous luminal dilatation feature, which makes it possible to implant a graft, i.e. an artificial tissue, after dilation of the lumen. Peripheral vascular as well as coronary angioplasty can be performed. For example, conventional percutaneous luminal coronary angioplasty, which uses only balloon means, is angioplasty, which usually requires elective coronary artery bypass graft surgery, which is a much more complex and risky procedure. It is known that restenosis often occurs at the surgical site. When using small diameter versions of the device of the invention, e.g. a few millimeters, a surgical procedure for implanting the graft into the blood vessel is not necessary as it can be carried out by a simple percutaneous insertion. It is.

As long as the prosthesis used in the device of the invention is capable of radially expanding and self-securing when released into a blood vessel or other duct, It can be of any type. A particularly preferred prosthesis, or implant, is described in published British Patent No. 8411519. The subject matter disclosed in this British patent is incorporated herein by reference. The prosthesis, i.e. the implant, comprises a flexible tubular body having several individual rigid sections each extending helically about the centerline of the tubular body as a common axis. Moreover, it is made of a flexible wire element, and further includes a plurality of elements wound in the same direction and arranged axially offset from each other, said plurality of elements are also arranged axially offset from each other. and intersects multiple elements wrapped in opposite directions.
The diameter of such a prosthesis or implant can be varied by relative axial movement of the ends of the tubular body.

According to a variant of the invention, the prosthesis used in the device disclosed herein can be formed from a so-called recovery metal, for example a titanium nickel alloy with mechanical "memory ability". In such a variation, the prosthesis, which is in a radially contracted state, is maintained in such a state by cooling prior to insertion of the implant surrounded by the probe. During implantation, the implantation device and prosthesis can be heated after being released into the desired location by introducing a heating medium into a channel extending through the probe. Such heating acts to expand the prosthesis by inducing its recovery capabilities. Examples of suitable alloys for use in such mechanical memory prostheses include the nickel-based alloys described in US Pat. No. 3,174,851. The disclosure of this US patent is incorporated herein by reference. The functionality of such a prosthetic device is otherwise the same as described for other aspects disclosed herein.