FR2846872A1 - Device forming endoprosthesis with reduced ends comprises distal and proximal ends with reduced transverse section facilitating passage in catheter guide - Google Patents

Abstract

The endoprosthesis forming device (10) comprising a distal end (10a) and a proximal end (10b) comprises a reduced transverse section (11) facilitating the passage of the device in a stenosis canal or catheter guide.

Description

i The invention essentially relates to a device forming a stent

  comprising a proximal end and a distal end, comprising means facilitating the passage of the device through an obstacle.

STATE OF THE ART

  Endoprosthetic devices, known in everyday language

  "stents" are used to treat narrowing of various conduits in the human anatomy such as an artery and to keep them open.

  There are different types of stents, which are described in

numerous patents.

  However for the establishment of this device forming

  stent, for example during angioplasty, it is necessary to use a guide catheter as well as a flexible guide.

  The guide catheter is placed upstream of the stenosis, for example upstream of a stenosed artery, the flexible guide, by passing through the

  through the stenosis, extends downstream of it.

  The stent device before being placed in the final position is in the retracted position relative to the stenosis.

  There are different modes of expansion for these devices forming stents, in order to put it in place, such as in particular

  self-expansion or balloon expansion.

  However, when the conduit o must be placed, the endoprosthesis device is too small, in particular when the latter is reduced by a diameter smaller than that of the outside diameter of the endoprosthesis device, the manipulator is unable to dispose

these measures.

  The manipulator is then led to remove the entire stent device from the patient's body.

  The manipulator is then exposed to a difficulty which resides in the fact that the proximal part of the device forming a stent collides with the entry of the guide catheter, which can lead to the disruption.

  partial, even complete, of the device forming a stent.

  On the other hand, it is also possible that the manipulator, when introducing the stent device into a highly stenosed lesion, causes the stent device to abut against

the calcified part.

GOALS OF THE INVENTION

  The main object of the present invention is to resolve the

  new technical problems stated.

  The object of the invention is to solve the new technical problem which consists in finding a solution which makes it possible to improve the operation of removing the entire device facilitating the placement of the stent device inside the guide catheter during a

removal from the patient's body.

  The present invention also aims to resolve the

  new technical problem consisting in facilitating the passage of the device 20 forming a stent through a stenosis.

  The present invention also aims to resolve the

  various technical problems stated by applying to all forms of existing endoprosthesis devices or "stents", such as in particular devices forming tubular, single filamentary stents, with braided or knitted mesh.

  In addition, the present invention aims to apply to all modes of expansion, such as in particular to devices forming

  self-expanding, or balloon expandable stents.

  The present invention also aims to be usable in all fields requiring it, such as in particular the

  interventional cardiology and vascular radiology.

  The object of the invention is to provide a solution to the technical problems stated by a particularly simple design, relatively inexpensive, usable on an industrial and medical scale.

DESCRIPTION OF THE INVENTION

  Thus, according to a first aspect, the present invention provides a stent device comprising a proximal end and a distal end, characterized in that it comprises at least one means facilitating the passage of the device in a conduit, such as a conduit. blood or a guide catheter, especially at an obstacle, by

  example a stenosis or the tip of a guide catheter.

  The proximal end may include a plurality of proximal end edges and the distal end may include a

  plurality of distal end edges.

  According to an advantageous embodiment of the invention, the means facilitating the passage is arranged at least on some of the edges of said proximal or distal end, preferably at both ends

  respectively proximal and distal.

  According to an advantageous embodiment, the means facilitating the passage comprises a cross section reduced to at least one

extremity, distal or proximal.

  According to an advantageous embodiment, the reduced cross section comprises at least one bevelled part produced on

  at least one or some edges of the distal or proximal end.

  According to an advantageous embodiment, the device forming

  endoprosthesis, comprising a distal end and a proximal end, is formed by one or more metallic wires wound in a zig-

  zag, defining elbows or edges, at least one of said elbows or edges present at the proximal and / or distal end comprises said means

facilitating the passage.

  According to an advantageous embodiment, the means facilitating the passage is carried out mechanically in the material of the device, for example by crimping, or flattening or machining by

chip removal.

  According to an advantageous embodiment, the means facilitating the

  passage includes an end piece secured to at least one of the proximal (12) or distal (14) end edges of the device.

  The proximal and / or distal end generally includes a plurality of end edges. In the context of a stent-forming device formed by one or more metal wires wound in a zigzag, defining bends or edges, the end edges are notably formed by some of the edges present at the ends of the device. Advantageously, the endoprosthesis device comprises

  a plurality of means facilitating the passage of the device.

  Advantageously, the means facilitating the passage comprises a bevel, with or without a flat, on at least one of the end edges, and in particular on one end of at least one aforementioned edge. The flat is preferably at least 0.025 mm. The flat part makes it possible to obtain a less dangerous end edge, in particular by limiting the point or thickness represented by this end edge, and by constituting a surface inclined towards the axis of the device facilitating the sliding of the end for either enter the narrow passage of the

  stenosis, either inside the guide catheter for removal.

  Advantageously, the bevel has an angle alpha (ac)

  defining the angle of the bevel, said angle preferably being between 30 1 and 890, and more preferably between 5 and 55.

  Advantageously, the bevel extends over a length varying from 0.1 mm to the entire length of the device. Thus according to a variant, at

  at least one wire used to make the device or stent is bevelled.

  A particularly advantageous embodiment is found 5 by choosing an angle a of between 20 and 400 and preferably

  when the angle ac is about 30.

  The invention can be achieved by presenting a means facilitating the passage of the device only on certain end edges of

  the proximal and / or distal end.

  It is obviously understood by the inventors that an advantageous embodiment resides in a device forming a stent comprising all of the end edges of the distal ends or

  proximal, provided with means facilitating the passage of the device.

  The invention can be carried out by carrying out one of the embodiments at one of the end edges, proximal or distal, advantageously the invention is carried out on all of the end edges, proximal or distal and , even more advantageously, on all of the end edges, proximal and distal. Therefore, in this very advantageous embodiment, the proximal end and the distal end have end edges each comprising

  means facilitating the passage of the device in a conduit.

  The endoprosthesis device can be produced from metal wire, for example, made of stainless steel such as 316L stainless steel, or other metals such as, for example, tantalum, or mixtures of metals such as, for example, nitinol. This substrate can be coated with an inorganic layer, for example of carbon, silicon carbide, nitride of titanium oxide, titanium, cobalt-chromium, platinum, silicones, polymers. This substrate can also be coated with a layer capable of releasing drugs with antimitotic, anti-inflammatory or immunosuppressive power. The wire diameter can vary within wide limits

  well known to those skilled in the art, generally between 0.05 and 0.20 mm.

  DETAILED DESCRIPTION OF THE INVENTION

  This invention can for example be used in the context of an angioplasty and a surgical operation to repair a stenosis requiring the placement of a stent or more

  usually a stent device.

  In particular, the manipulator must, in this type of operation, have an assembly comprising a guide catheter; a generally flexible guide; a balloon carrier catheter for carrying at least one stent device arranged at least externally around the balloon in the deflated state, in a conduit, by

  example formed by an artery or possibly a vein.

  As is well known to those skilled in the art, the guide catheter is first advanced upstream of the stenosis. Then, the flexible metal guide is introduced through the stenosis to the downstream thereof. Finally, the carrying catheter with its endoprosthesis device is inserted into the guide catheter by sliding on the guide. 20 At this point, it may happen that the stent device cannot

  not penetrate through the passage defined by the stenosis.

  The present invention provides a means as described above for facilitating the passage of the stent device within a stenosis having a hollow interior portion. The inventors understand by "a hollow interior part", the reduced passage left by the stenosis to allow a fluid, such as

  blood, to flow through a conduit, such as an artery or a vein.

  However, if the endoprosthesis device according to the invention or according to the prior art does not pass through the stenosis, the manipulator is forced to remove the assembly {device forming

  stent; balloon carrier catheter} of the patient's body.

  For this, the manipulator must reposition the assembly {endoprosthesis device and balloon carrier catheter} in the catheterguide. However, during this removal, the endoprosthesis device may abut against the entry of the guide catheter and partial or complete disruption of the endoprosthesis device

  relative to the carrier catheter, occurs.

  The present invention provides means previously described to allow the reinsertion of the assembly {device forming

  stent and its supporting catheter} in the guide catheter.

  Other objects, characteristics and advantages of the invention

  will appear clearly in the light of the following description, made with reference to the appended drawings, representing several modes of

  currently preferred embodiment of the invention, given simply by way of illustration, and which therefore cannot in any way limit the scope of the invention. In the figures - FIG. 1 represents a first currently preferred embodiment of a stent device (10), according to the present invention, in which the means (11) facilitates the passage of the stent device in a conduit is a bevel (400); - Figure 2 shows a detailed view of an end edge, such as a distal end edge (14) and / or a proximal end edge (12) of the device of Figure 1; - Figure 3 shows another embodiment of the means (11) of the present invention showing a detailed view of an end edge such as a distal end edge (14) and / or proximal (12) of the device; - Figure 4 shows another embodiment of the means (11) of the invention, showing a detailed view of an end edge, such as a distal end edge (14) and / or proximal (12) of the device; - Figure 5 shows an embodiment in which the means (11) is an integral end piece (500), making it possible to reduce the section of at least one of the ends, proximal or distal; FIG. 6 represents an embodiment in which the means (11) is a proximal (12) and / or distal (14) end edge having sufficient flexibility to allow a reduction in the terminal external diameter (34) allowing to cross an obstacle by positioning to delimit a new terminal outer diameter (34 '); - Figure 7 shows a device forming a stent (50), according to the prior art, having planar end edges; - Figure 8 shows a device forming a stent (50), according to the prior art, in abutment against an obstacle (100) formed here by the guide catheter, when removing the device forming a stent (50) from the body "a patient by example; FIG. 9 represents a device according to one of the embodiments of the means (11) of the present invention, in particular a device forming a stent (10) having at least the bevelled proximal end edges (12), in abutment against an obstacle, during the withdrawal of the device, facilitating the passage of the device through the obstacle (100), formed here by the guide catheter, thereby allowing to penetrate again inside the guide catheter; - Figure 10 shows a device (50), according to the prior art in abutment against an obstacle (200) during the establishment of the device, for example during an intervention on a stenosis; - Figure it represents a device according to one of the modes of embodiment of the means (11) of the present invention, for example a stent device (10) having at least one of the beveled distal end edges (14), in abutment against an obstacle (200) during the setting in place of the device, facilitating the installation of the device at

across the obstacle (200).

  Figure 1 shows a first embodiment

  currently preferred of a stent device, according to the present invention, represented by the general reference number (10).

  This stent device comprises a proximal end (10a) defined by a set of proximal end edges (12) and a distal end (10b) defined by a set of distal end edges (14), interconnected by a central part (16), forming the body

of the device.

  The means (11) is a bevel (400) in this particular embodiment. The edges of the proximal (12) and distal (14) ends have a bevel, for example having an angle of the bevel cx having a value varying from 1 to 890, but preferably being between 5 and 550, and being in a mode particular embodiment of approximately 300, and preferably 270. The edges of proximal (12) and distal (14) ends 20 also have a flat (21) of length (20) between 0.01 mm and the thickness (18) of the stent device. This stent forming device advantageously has its thickness (18) equivalent to that of stent forming devices known by

  those skilled in the art and is generally between 0.05 and 0.20 mm.

  In an advantageous embodiment, the thickness (18) corresponds to the thickness of one or more metallic wires (17) wound in

  zig-zag for forming the device forming a stent.

  The body of the device or central part (16) makes it possible to define an outside diameter (30) and an inside diameter (32), as well as a terminal outside diameter (34) and a terminal inside diameter (36). The general aim of the invention is to obtain a diameter

  (34) and / or (36) smaller than the diameter (30).

  This structure makes it easier to pass through an obstacle having a hollow part into which the device forming a stent 5 must be inserted, such as in particular through a

stenosis, or a guide catheter.

  Figure 2 shows a detail of the bevel (400) of the proximal (12) or distal (14) end edges of the embodiment of Figure 1. This figure also shows a top view of such an end, by example of a device forming a stent with rounded ends, having a bevel. This figure represents the thickness (18), as well as the thickness (20) given by the flat (21), if the latter is present. Likewise the length (15) represents the length of the bevel (400) on the outer surface in this embodiment. The bevel can extend over a length (15) varying from 0.01 mm to the entire length of the device. We can in particular identify the angle ca representing the angle of the bevel, this angle possibly varying from 1 to 890, but preferably being between 5 and 550 and being within a

  particular embodiment of approximately 300 and preferably 270.

  FIG. 3 represents another embodiment of the means

  (11), and in particular represents the angle (x defined by the angle of the bevel and represents the angle f3 defined by the half angle at the top of the interior of the truncated cone formed in space by all of the proximal (12) or distal (14) end edges, when all of these end edges have means (11) facilitating the passage of the device.

  Figure 4 shows another embodiment of the means (11) of the present invention, wherein the stent device (10) comprises a device body (16) having an outer diameter (30) and an inner diameter (32) . The proximal (12) or distal (14) end edges as a whole form an outer terminal diameter (34) and an inner terminal diameter (36), which are

  smaller than the diameters (30) and (32) respectively.

  In this embodiment, the thickness (18) is retained, however, the intermediate part (40) may have a different thickness. Similarly, the end edge (12) or (14) may have a

  thickness (20) different or identical.

  In an advantageous embodiment, the end edge (12) or (14), in this particular embodiment, can have a

  bevelled shape as described in figure 2.

  FIGS. 5A and 5B represent a beveled end piece (500) secured to a device forming a stent, so as to facilitate the passage of the device in a conduit. This end piece (500) is shown in an embodiment corresponding to FIG. 2. However, the end pieces can cover all of the embodiments concerned by the invention and in particular the embodiments provided for in Figures 3, 4 and 6. FIGS. 5A and 5B therefore show two different embodiments of a beveled end piece secured (500), without limiting it

the form.

  FIGS. 5A and 5B show a proximal (12) and / or distal end edge (14) having an integral end piece (500) at the end of a device forming a stent of the prior art for example. This joined end piece (500) is placed on the end of a stent device having the previous drawback and not solving the problem posed and resolved by the present invention. This

  integral end piece (500) can take the various forms provided by the invention in general. This joined end piece (500) may be in the form of an end piece secured to one of the proximal (12) or distal end edges (14), or of a set of end edges 30 to be joined to the proximal (12) or distal (14) end.

  FIG. 6 represents a device forming a stent showing an embodiment according to which the proximal (12) and / or distal (14) end edges comprise a flexible part. This allows the endoprosthesis devices (10) to pass from an outer terminal diameter 5 formed by all of the proximal (12) or distal (14) end edges to a new outer terminal diameter formed by the end edges. proximal (12) or distal (14), the diameter (34 ') being less than the diameter (34) and facilitating the passage of the device

  forming a stent (10) through an obstacle.

  FIG. 7 represents a device forming a stent of the prior art (50). This device has a planar shape at the ends, and in particular a thickness (20 ′) at the ends identical to the thickness

(18 ') from the central part.

  Figure 8 shows a prior art stent device (50) abutting an obstacle (100). This figure represents in particular the contact between at least one edge of proximal end (12 ') of the prior art and the obstacle (100) during the withdrawal of the device in a conduit (101); this obstacle can be the edge of a

  guide catheter, upon removal of the device (10) therein.

  FIG. 9 represents a device forming a stent (10) according to the invention, for example according to one of the embodiments as described in FIG. 1 or 2, in abutment against an obstacle (100). This figure makes it possible to visualize how the passage of the endoprosthesis device (10) is facilitated through an obstacle (100) thanks to the proximal end edges (12) provided with means (11) facilitating the passage, here a bevel, when removing the devices forming

  stent in a conduit (101) for example, a guide catheter.

  FIG. 10 represents a device forming a stent of the prior art (50) in abutment against an obstacle (200), formed for example by a stenosis. This figure represents in particular the contact between at least one distal end edge (14 ′) of the prior art and the obstacle (200), which can for example be a stenosis, during the fitting of the device (50 ). This figure also represents a conduit (300) not impeding the passage of the device forming a stent, this conduit (300) may for example be an artery. This figure also represents the guide catheter (70), the balloon carrying catheter (80), on which is mounted the device forming a stent (50) of the prior art, and on which is represented radiographic marks (61) allowing to correctly place the stent device 10 before expansion. In this figure, it is easily understandable the difficulty represented by the passage of the device (50) through the obstacle (200); FIG. 11 represents a device forming a stent (10) according to the invention, for example according to one of the embodiments as described in FIG. 1 or 2, in abutment against an obstacle (200), formed by

  example by stenosis. This figure makes it possible to visualize the way in which the passage of the endoprosthesis device (10) is facilitated through an obstacle (200), thanks to the distal end edges (14), for example during the positioning of the device. forming a stent (10) 20 through this obstacle (200).

  The references of the figures are identical for all of Figures 1 to 11, and the applicant has not considered it necessary to repeat for the

  description of each figure all of these benchmarks.

  It is understood that the invention gives rise to various embodiments and includes all the means constituting equivalents

  techniques of the means described and represented.

  Figures 1 to 11 are an integral part of this

  invention and therefore of the present description.

  The invention also covers any feature which appears new from the description and the drawings themselves, with respect to

  in the state of the art and as a general means. It is also understood that one can combine the various embodiments and manufacturing between them. It is possible, for example, to make the combination of restricting the diameter of the external section of a distal or proximal end and to adjust a nozzle also comprising a restriction of the diameter of the external section.

  Other objects and advantageous features of the invention

  will appear clearly to those skilled in the art from the following description made with reference to an exemplary embodiment given by way of illustration and which in no way limit the scope of

the invention.

EXAMPLE 1

  A prior art stent device, for example, bevel helical LIC7 (manufacturer: HEXACATH), is machined by

  chip removal so as to present a set of proximal terminal ends (12) and distal terminals (14). (The references given in relation to the references of the figures). These ends are machined so as to make a bevel having a bevel angle of 20,270.

  The end of this bevel has a flat area of about 0.025 mm. The machined part extends over a length of approximately 0.12 mm

from one end.

Claims (13)

  1. Stent forming device (10), comprising a distal end (10a) and a proximal end (O10b), characterized in that it comprises at least one means (11) facilitating the passage of the device 5 in a conduit, such as '' a blood line or a guide catheter, in particular at the level of an obstacle, for example a stenosis or the tip of a guide catheter.   2. A stent device (10) according to claim 1, wherein the proximal end (10a) comprises a plurality of edges   proximal end (12) and the distal end (O10b) comprises a plurality of distal edges (14), characterized in that said means (11) facilitating passage is arranged at least at one of the proximal end edges (12 ) or distal (14), preferably at both proximal and distal ends.   3. Stent forming device (10) according to claim 1   or 2, characterized in that the means (11) facilitating the passage comprises a cross section reduced to at least one end, proximal (10a) and / or distal (O10b).   4. Device forming a stent (10), according to claim 3,   characterized in that the reduced cross section includes at least one beveled portion forming a bevel (400) formed on at least one or some proximal (12) and / or distal end edges (14).   5. A stent forming device (10) according to any one of the preceding claims, comprising a distal end (O10b) and a proximal end (10a), formed by one or more metallic wires (17) wound in a zig-zag, defining of 30   elbows or edges, characterized in that at least one of said elbows or edges present at the proximal (10a) and / or distal (lob) end comprises   said means (11) facilitating the passage.   6. Stent forming device (10) according to any one   of the preceding claims, characterized in that the means (11) facilitating the passage is produced mechanically in the material of the device, for example by crimping, or flattening, or a machining by chip removal.   7. Stent forming device (10) according to any one   of the preceding claims, characterized in that the means (11) facilitating the passage is an end piece secured (500) to at least   one of the proximal (12) or distal (14) end edges of the device. 15 8. Device forming a stent (10), according to any one   of the preceding claims, characterized in that it comprises a   plurality of means (11) facilitating the passage of the device.   9. Device forming a stent (10), according to any one   of the preceding claims, characterized in that the means (11) facilitating the passage comprises a bevel (400) having a flat (21) on at least one of the proximal (10a) or distal (lob) ends,   preferably the flat (21) is at least 0.025 mm. 25 10. Device forming a stent (10) according to any one   of the preceding claims, characterized in that at least one of the proximal (12) and / or distal (14) end edges have an angle alpha ((x) defining the angle of the bevel, said angle preferably being between 1 and 890, and more preferably between 5 and 55.   11. Device forming a stent (10), according to claim 10, characterized in that the angle alpha (c) is between 20 and 400, and is preferably around 30.   12. Device forming a stent (10), according to any one   of the preceding claims, characterized in that the means (11) facilitating the passage comprises a bevel extending over approximately 0.12 mm on each proximal (12) or distal (14) end edge of the device 10 forming a stent.   13. Endoprosthesis device (10), comprising a distal end (10a) and a proximal end (o10b), comprising at least one means (11) facilitating the passage of the device in a conduit 15 (101; 300), such as a blood conduit, or a guide catheter, in particular at the level of an obstacle (100; 200), for example a stenosis or the end of a guide catheter, the endoprosthesis device being formed by one or more metallic wires (17) wound in a zigzag, defining elbows or edges, at least one of said elbows or edges 20 present at the proximal (10a) and / or distal end (O10b) comprises said means (11) facilitating passage, said means (11) facilitating the passage being a bevel (400) produced on at least one of said elbows present at the proximal and / or distal end, the angle alpha (cL) defining the angle of the bevel is about 27, the end of the bevel has a flat part (21) of about 0.025 mm, the bevel was nt carried out over a length (15) of about 0.12 mm.