CN217960410U - Covered stent - Google Patents

Abstract

The utility model provides a covered stent relates to medical instrument technical field, include: a scaffold, the scaffold divided into: the stent comprises a stent proximal section and a stent distal section, wherein the stent proximal section and the stent distal section both comprise one or more metal wire frames which are arranged at intervals along the axial direction of the covered stent; the bracket middle section comprises a closed ring structure consisting of one or more metal wires, and the closed ring structure is axially arranged between the bracket proximal section and the bracket distal section; the film is fixedly connected with the stent proximal section and the stent distal section, and the middle part of the film is wrapped on the middle section of the stent; and the film covering opening is arranged on the film covering and corresponds to the middle section of the stent, and a sewing allowance is reserved on the film covering opening. The utility model provides a not enough problem that leads to of branch's support aversion of tectorial membrane support's structure holding power among the prior art, promote tectorial membrane support's structural strength, avoid plastic deformation.

Description

Covered stent

Technical Field

The utility model relates to the technical field of medical equipment, especially, relate to a tectorial membrane support.

Background

Aortic Dissection (AD) refers to a disease in which the vascular wall layer is detached due to destruction of the media in the blood vessel caused by bleeding in the Aortic vessel wall, and then a true or false lumen is formed, which may or may not be interconnected (see fig. 1 and 2, where X denotes the direction of blood flow). In most cases, aortic dissection is initiated by intimal tear through which blood enters the media, eventually leading to rupture of the aorta or re-entry into the true lumen through a second intimal tear. The aortic dissection can be caused by various factors such as hypertension, atherosclerosis, severe trauma and the like.

Aortic dissection, although rare (annual incidence of four ten-thousandths), is extremely violent and highly lethal. Hospitalization mortality in patients undergoing open surgery is around 10% when the lesion involves the ascending aorta or aortic arch branch vessels (Stanford type a dissection). More importantly, many patients die without help because the onset is very rapid (the mortality rate for Stanford type a sandwiches at 48 hours after onset is 40% to 50%).

At present, abdominal aortic aneurysm, thoracoabdominal aortic aneurysm or aortic dissection tumor which does not involve branch arteries can be treated by adopting an intracavity interventional therapy mode through a covered stent, but when the lesion involves ascending aorta or aortic arch branch vessels, the current gold standard of operation is surgical open thoracic surgery: grandson's surgery or cryo-rhinoplasty (total arch replacement surgery); however, the current gold standard operation requires complete excision of the aortic arch region for replacement with an artificial blood vessel in extracorporeal circulation, and requires a doctor to complete 5-site (descending aorta, left common carotid artery, ascending aorta, left subclavian artery, innominate artery) anastomosis of the artificial blood vessel with the end of the autologous blood vessel. The operation time is about 6 hours, the extracorporeal circulation time is about 4 hours, the aorta blocking time is about 2 hours, and the deep hypothermia stopping circulation time is about 50 minutes. In a word, the operation is complex, the time is long, and the operation is not easy to popularize.

At present, the tectorial membrane support among the prior art comprises a plurality of wire frames, a plurality of connecting pieces and the tectorial membrane of laminating on wire frame and connecting piece, and its bow leaves the axial opening who runs through tectorial membrane and tectorial membrane support, and in addition, the approximate operation flow in this kind of tectorial membrane support application actual operation is: first, an axial incision is made in the aortic arch; secondly, placing the main body covered stent; then, windowing the main body film coating bracket (if windowing is performed, the step can be omitted); then, placing the branch covered stent; and finally, suturing the opening of the aorta covered stent, and then suturing and fixing the stent and the blood vessel to complete the full-arch repair.

However, the structure of the bow opening has the following problems:

1. the open support has a lower holding force than the closed structure. Insufficient support force may cause displacement of the branch stent. Meanwhile, insufficient supporting force may cause the covered stent to be attached to the inner wall of the blood vessel in a complementary manner, so that a false cavity is formed by the covered stent and the stent on the inner wall of the blood vessel;

2. when the bracket with the opening is pressed and held, plastic deformation can be caused due to uneven stress, and the releasing of the bracket and the shape after the releasing are influenced;

3. the stent has limited relative movement of the inner ring and the outer ring at a large bend due to the sewing at the opening, and interference may occur when branches are placed.

In view of the foregoing, there are improvements to the prior art stent grafts.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned shortcomings of the prior art, the present invention provides a stent graft for solving the problem of the displacement of the branch stent caused by insufficient structural support force of the stent graft in the prior art.

To achieve the above and other related objects, the present invention provides a stent graft, comprising: a scaffold, the scaffold divided into: the stent comprises a stent proximal section and a stent distal section, wherein the stent proximal section and the stent distal section both comprise one or more metal wire frames which are arranged at intervals along the axial direction of the covered stent; the middle section of the bracket comprises a closed ring structure consisting of one or more metal wires, and the closed ring structure is axially arranged between the proximal section of the bracket and the distal section of the bracket; the film is fixedly connected with the stent proximal section and the stent distal section, and the middle part of the film is wrapped on the middle section of the stent; and the film covering opening is arranged on the film covering and corresponds to the middle section of the stent, and a sewing allowance is reserved on the film covering opening.

In an embodiment of the present invention, the suturing allowance is reserved on a side opening wall or two side opening walls of the tectorial membrane opening, and is arranged along the radial direction of the middle section of the support for surgical suturing.

In an embodiment of the present invention, the support comprises a shape memory alloy support.

In an embodiment of the present invention, the wire frame is wavy along the axial direction while extending in the circumferential direction.

In an embodiment of the present invention, the plurality of wire frames are wavy or latticed, and the distance between two adjacent wire frames is the same or different.

In an embodiment of the present invention, the wire frame includes a peak, a trough and a connection, the peak and the wave rod of the trough, the wave rod and the peak/trough are tangent or not tangent.

In an embodiment of the present invention, the axial positions of the wave crests and the wave troughs in each of the metal wire frames in the stent-graft are opposite or staggered.

In an embodiment of the present invention, the metal wire frame of the proximal section of the stent has a closed ring structure and the whole diameter of the metal wire frame of the distal section of the stent is reduced or increased in sequence.

In an embodiment of the present invention, the closed ring structure includes a metal wire, the metal wire is wound along the axial spiral shape, and both ends of the metal wire respectively with the support proximal section and the support distal section are connected.

In an embodiment of the present invention, the closed ring structure includes a metal wire, and the metal wire is wound at intervals along the axial direction to form a plurality of metal rings.

In an embodiment of the present invention, the two ends of the metal wire are respectively connected to the metal wire frame or the film.

In an embodiment of the present invention, the closed ring structure includes a plurality of metal wires, each of which is circumferentially arranged around a closed metal ring, and a plurality of the metal wires are arranged along the axial interval, and the metal wires correspond to the small bending of the vascular curve and are sewn up with the covering film.

In an embodiment of the present invention, two adjacent connecting rods are connected between the closed metal rings through the connecting rods, two adjacent connecting rods are disposed in a staggered manner, and the interval is three, the axial positions of the connecting rods on the closed metal rings are the same.

In an embodiment of the present invention, the closed loop structure includes a plurality of metal wires, every when the metal wire surrounds along circumference to it is wavy, and many along axial fluctuation the metal wire is arranged along axial interval, the metal wire correspond the crooked little bend of blood vessel with the tectorial membrane is sewed up.

In an embodiment of the present invention, the metal wire includes a peak, a trough and a wave rod connected to the peak and the trough, and the wave rod is tangent or not tangent to the peak/trough.

In an embodiment of the present invention, the axial positions of the wave crests and the wave troughs in two adjacent metal wires are opposite or staggered.

In an embodiment of the present invention, the metal wire includes two metal wire segments, and the two metal wire segments have different wavelengths.

In an embodiment of the present invention, the smaller wavelength of the metal wire corresponds to the small curve of the stent graft in the curved state, and the larger wavelength of the metal wire corresponds to the large curve of the stent graft in the curved state.

In an embodiment of the present invention, the wave crest or the wave trough of the metal wire with a smaller wavelength is sewed with the covering film by a medical suture.

In an embodiment of the present invention, the opening position of the film covering opening on the covered stent corresponds to a junction of two metal wire segments in the metal wire.

As mentioned above, the utility model discloses a covered stent has following beneficial effect:

1. through adopting closed loop structure at the support interlude of covered stent for adjacent closed loop structure can adjust the interval, and obtains the biggest interval in big bend, and this helps branched smooth installation. Meanwhile, the bracket is in a closed loop structure, and can provide larger supporting force than the bracket with the opening.

2. When the tectorial membrane support of branch artery is placed to tectorial membrane support's windowing in the aorta, the utility model discloses a tectorial membrane support can avoid placing in-process branch artery tectorial membrane support system and aorta tectorial membrane support's in metal stent interference.

3. After placing the covered stent in the aorta, when windowing the corresponding position of department of origin of branch artery to the covered stent, the utility model discloses a covered stent can avoid windowing the interference of position and metal support.

4. Adopt the closed loop structure through the support interlude at the covered stent, there is open-ended loop structure relatively, distribute more even performance when having the circumference atress, can avoid when the support is pressed and is held because of the atress is uneven (local atress is too big promptly) the condition that causes plastic deformation takes place.

Drawings

FIG. 1 is a schematic view of a normal aorta;

FIG. 2 shows a schematic representation of aortic dissection;

FIG. 3 is a schematic view of a stent graft according to an embodiment of the present invention;

FIG. 4 is a schematic view of the sewing margin of the opening of the covering film according to an embodiment of the present invention;

FIG. 5 is a schematic perspective view of a wire frame of a stent graft according to an embodiment of the present invention;

fig. 6 is a schematic structural view of a wire frame according to an embodiment of the present invention;

fig. 7 is a schematic size diagram of a wire frame according to an embodiment of the present invention;

FIGS. 8a-8c are schematic views showing three alternative forms of the peaks or valleys of the stent graft of the present invention;

FIG. 9 illustrates a front view of a wire frame of a stent graft in an embodiment of the present invention;

FIGS. 10a-10f are schematic views of six alternative forms of the closed loop structure of the stent graft of the present invention;

fig. 11 is a schematic size diagram of a closed loop structure according to an embodiment of the present invention.

Description of the element reference

100. A covered stent; 10. a wire frame; 101 (101'), a peak; 102 (102'), a wave bar; 103 (103'), a wave trough; 11. a stent proximal segment; 12. the middle section of the bracket; 13. a bracket telecentric section; 20. a closed loop structure; 201. a metal wire; 202. A metal ring; 203. a closed metal ring; 2031. a connecting rod; 204. a metal wave ring; 30. coating a film; 301 coating film opening; 302. stitching allowance; 401. the ascending aorta; 402. the descending aorta; 403. the brachiocephalic trunk artery; 404. the left common carotid artery; 405. the left subclavian artery; 406. an inner membrane tear; 407. a false lumen.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can be implemented or applied by other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to fig. 1 to 11. It should be noted that the drawings provided in the present embodiment are only for schematically illustrating the basic concept of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, amount and proportion of each component may be changed arbitrarily and the layout of the components may be more complicated.

For convenience of description, the terminology appearing herein is to be interpreted:

small bending: blood vessels, stents, etc. are quasi-circular tubular shapes, and when they are bent, the side with the smaller bending radius is the small bending side.

Bending greatly: blood vessels, stents, and the like are similarly tubular, and when they are bent, the side with the larger bending radius is the large bending side.

Proximal end: the arterial blood vessels from the heart gradually branch into capillaries and then gradually merge into venous blood vessels back to the heart, wherein the end of any segment of the blood vessels close to the heart is called the proximal end.

Distal end: the arterial blood vessel from the heart gradually branches into capillaries and then gradually merges into venous blood vessels to return to the heart, wherein the end of any section of the blood vessel far away from the heart is called the far end.

Axial direction: blood vessels, interventional stents, and the like are all in the shape of a quasi-circular tube, and if they are regarded as a cylinder, the cylinder rotation axis is defined as the axial direction.

Radial: the radial direction is perpendicular to the axial direction, namely the radius or diameter direction of the end face circle of the cylinder, and the radial direction is perpendicular to the axial space.

Circumferential direction: "circumferential" or circumferential direction, which together with "axial" and "radial" constitutes the three orthogonal directions of the cylindrical coordinates.

The utility model provides an art tectorial membrane support (also can be called tectorial membrane support 100), wherein, fig. 3 and fig. 4 show the utility model discloses a tectorial membrane support's schematic structure. As shown in fig. 3 and 4, the stent graft 100 is used as a whole prosthesis for treating aortic diseases such as aortic dissection accumulated in branch vessels, and the stent graft 100 is an assembly body formed by combining two components such as a stent and a stent graft 30 through a certain process, wherein the stent graft comprises a wire framework 10 and a closed loop structure 20.

Referring to fig. 3 and 4, in the present invention, the stent graft 100 is composed of a plurality of rings of annular wire frames 10, a closed loop structure 20, and a stent graft 30, and the plurality of rings of wire frames 10 are distributed at two axial ends of the stent graft 100 to form a stent proximal section 11 and a stent distal section 13; the closed loop structure 20 is distributed in the middle of the covered stent 100 and is positioned between the stent proximal section 11 and the stent distal section 13 to form a stent middle section 12; it should be noted that the length of the stent graft 100 is in the range of 60-360mm, and the lengths of the stent proximal section 11, the stent distal section 13 and the stent middle section 12 are all in the range of 20-120 mm. The multiple circles of metal wire frames 10 on the stent proximal section 11 and the stent distal section 13 are sequentially arranged at the two ends of the stent graft 100 in parallel at intervals, that is, the metal wire frames 10 and the connecting pieces 30 are axially distributed at intervals at the two ends of the stent graft 100.

The overall diameters of the stent proximal section 11, the stent middle section 12 and the stent distal section 13 are different, and the diameters of the parts are sequentially increased or decreased, so that the whole stent graft 100 has a certain taper, and the taper is controlled by the length of the stent graft 100 and the diameters of the parts. In addition, the tectorial membrane 30 is wrapped on the outer surface of the tectorial membrane stent 100 and is tightly attached to the metal wire frame 10 in the stent proximal section 11 and the stent distal section 13 in a sewing or pasting mode, so that the fixation of the metal wire frame 10 can be realized; the position of the cover film 30 corresponding to the middle section 12 of the stent is hollow, which provides the operational conditions for the manner in which the closed loop structure 20 and the cover film 30 are sutured together as will be discussed below.

The stent graft 100 has strong bending resistance and support performance, and after the stent graft 100 is implanted into a diseased region, the stent graft 100 can be anchored and supported at the diseased region by means of a plurality of wire frames 10 to prevent the displacement of the stent graft 100. The spacing between the wires contained within the closed loop structure 20 can be adjusted, particularly the spacing that is maximally available at large bends of the closed loop structure 20 to free branches. The cover film 30 has high sealing performance, when the cover film 30 is implanted into a diseased part, the cover film 30 can cover the diseased part and seal the diseased part, so that blood in the aorta is prevented from entering the tunica media of the blood vessel from the crack of the tunica intima, the tunica media of the blood vessel are prevented from being continuously separated, and the disease is relieved.

Referring to fig. 3, 4, 5 and 6, in the present invention, the wire frame 10 is one of the components constituting the stent graft 100, and the stent graft 100 includes a plurality of wire frames 10. Each wire frame 10 extends along the circumferential direction of the stent graft 100 to form a closed loop; in addition, the number of wire frame 10 in support proximal heart section 11 and support telecentric sections 13 all is between 2 ~ 15, the utility model discloses the number that wire frame 10 is located support proximal heart section 11 and support telecentric sections 13 does not do too much injectly, can satisfy the required support performance of tectorial membrane support 100 and compliance can.

The utility model discloses in, wire frame 10 can be buckled for circular shape wire by a cross section, heat treatment design forms, still can have a circular cavity metal column to form through laser cutting, and wire frame 10 is whole to be circular or approximate circular shape ring, and wire frame 10 is when circumference extension, and it is wavy to appear undulating in the axial. The wire frame 10 is made of a metal material, such as nickel titanium alloy (NiTi). The overall height H1 of the wire frame 10 is in the range of 5-30mm, such as 5mm, 10mm, 15mm, 20mm, 25mm or 30mm; the overall diameter D1 of the wire frame 10 is in the range 10-50mm, such as 10mm, 20mm, 30mm, 40mm or 50mm; the cross-sectional diameter d1 of the wires of the wire frame 10 is in the range of 0.1-1mm, such as 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm or 1mm.

In an alternative embodiment, the wire cross-section of the wire frame 10 may also be square, trapezoidal, or other suitable shape, and when the wire cross-section of the wire frame 10 is square, the diagonal dimension of the square is defined as d1, which may range from 0.1mm to 1mm, such as 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, or 1mm.

In an alternative embodiment, the wire frame 10 may also be made by laser cutting a metal tube, expanding it by heat treatment, and shaping it. In an alternative embodiment, the wire frame 10 may also be fabricated in one step from 3D metal printing.

Referring to fig. 6 and 7, in the present invention, the wire frame 10 includes a peak 101, a valley 103 and two wave bars 102 connecting the peak 101 and the valley 103, one peak 101 and two adjacent wave bars 102 form a wave, the peak 101 and the valley 103 are relative, the wire frame 10 is inverted in the axial direction, the peak 101 becomes the valley 103, and the valley 103 becomes the peak 101. The number of waves of one wire frame 10 is not fixed, and the setting according to the physiological anatomical structure of the aorta is performed according to the values of the overall height H1 of the wire frame 10 and the overall diameter D1 of the wire frame 10. As an example, the wave number of one wire frame 10 is between 2 and 18, wherein the wave number of the wire frame 10 is 6 as shown in fig. 6.

In the present invention, the radius R1 of the excessive fillet between the wave crest 101 or the wave trough 103 is 0-5mm, such as 0mm (corresponding to the two adjacent wave bars 102 directly connected without the fillet), 1mm, 2mm, 3mm, 4mm or 5mm. The R1 values of a wire framework 10 are not necessarily the same, i.e. the peaks 101 or the troughs 103 of the same wire framework 10 may be the same or different. The magnitude of each R1 value should be set according to the requirements of the functions of the stent graft 100, such as later-stage crimping. As an example, in fig. 6 it is shown that several peaks 101 or valleys 103 of one and the same wire frame 10 are of the same size.

The utility model discloses in, the field angle (being the contained angle alpha 1 between two adjacent ripples poles) scope of crest 101 is 10-70, for example 10 °, 20 °, 30 °, 40 °, 50 °, 60 ° or 70 °, and a plurality of crest 101 field angle alpha 1 size in same wire frame 10 can be the same, also can be different, and the size of each alpha 1 value should be set for according to the demand of functions such as tectorial membrane support 100 later stage pressure is held.

Fig. 8a to 8c show the situation where all wave bars 102 of the wire framework 10 are tangent to their adjacent wave crests 101 or wave troughs 103 and all values of α are at the same acute angle (of course, obtuse angles are also possible). It is understood that the wave rod 102 and the wave peak 101 or the wave trough 103 can also adopt one of the wave forms shown in fig. 8a to 8c, wherein in fig. 8a, the wave rod 102 and the wave peak 101 or the wave trough 103 are not tangent, and α 1 is an acute angle, and the wave peak 101 or the wave trough 103 presents a major arc form; in fig. 8b, the wave rod 102 is not tangent to the peak 101 or the trough 103, and α 1 is an obtuse angle, the peak 101 or the trough 103 presents a minor arc shape; in fig. 8c, the peaks 101 or valleys 103 may be "M" or "W" shaped, etc.

Referring to fig. 7, in the present invention, the wave rod 102 is a straight rod connecting between the wave crest 101 and the wave trough 103. The length L1 of the wave bar 102 ranges from 1-35mm, such as 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, or the like. The lengths L1 of the wave bars 102 may be the same or different in the same wire frame 10. As an example, the case where the lengths L1 of all the wave bars 102 of each wire frame 10 are equal is shown in fig. 7.

As shown in FIG. 9, the relative positions of the plurality of wire frames 10 in the stent graft 100 may be the same or different. In the lower oval region of FIG. 9, the peaks 101 of two adjacent wire frames 10 are offset, and the peaks 101 of one wire frame 10 are located between the peaks 101 of another wire frame 10, such as two adjacent wire frames 10, and the peaks 101 of one wire frame 10 can be vertically opposite to the valleys 103 of another wire frame 10 in the axial direction, so that the wire frames 10 on the stent graft 100 are in a grid shape as a whole; in the upper oval region of FIG. 9, adjacent wire frames 10, the peaks 101 of one wire frame 10 may be axially angularly opposite the valleys 103 of the other wire frame 10, i.e., the peaks 101 of one wire frame 10 are between the valleys 103 of the other wire frame 10, e.g., the peaks of adjacent wire frames 10 are aligned, and the configuration is such that the wire frames 10 on the stent graft 100 are generally undulating.

Referring to fig. 10-11, in the present invention, the closed loop structure 20 is one of the components constituting the stent graft 100, and the closed loop structure 20 includes one or more wires 201. The closed-loop structure 20 extends along the circumferential direction of the stent graft 100 and forms a section of hollow thin-walled cylindrical structure, and it should be noted that the shape of the closed-loop structure 20 has various forms, such as: the wavy, spiral or circular shape, the closed loop structure 20 can be selected according to the specific lesion position or lesion degree of the aorta of the patient; in addition, the small bends of the closed loop structure 20 can be sutured to the stent graft 30 attached to the stent graft 100 at multiple points by means of sutures, whereby the spacing between the wires 201 contained within the closed loop structure 20 can be adjusted, particularly the spacing that can be maximally achieved at the large bends of the closed loop structure 20 to release the bifurcation, although in some embodiments, the small bends of the closed loop structure 20 may also be sutured without sutures.

Referring to fig. 11, the overall height H2 of one closed loop in the closed loop structure 20 is in the range of 5-30mm, such as 5mm, 10mm, 15mm or 20mm; the overall diameter D2 of one of the closed loops in the closed loop structure 20 is in the range of 10-50mm, such as 10mm, 20mm, 30mm, 40mm or 50mm; the cross-sectional diameter d2 of the wire 201 in the closed loop configuration 20 is in the range of 0.1-1mm, such as 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm or 1mm.

In an alternative embodiment, the cross-section of the wire 201 in the closed loop structure 20 may also be square, trapezoid, or other suitable shapes, and when the cross-section of the wire 201 in the closed loop structure 20 is square, the diagonal dimension of the square is defined as d2, which is in the range of 0.1-1mm, such as 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, or 1mm.

Referring to fig. 10a, in an optional embodiment of the present invention, the middle section 12 of the stent is formed by winding a metal wire 201, the whole closed loop structure 20 is spiral, and the position of the metal wire 201 corresponding to the small bend of the stent graft 100 and the outer-side-attached stent graft 30 are sewn by multiple points of medical suture, wherein two ends of the metal wire 201 are respectively anchored to one metal wire frame 10 of the proximal section 11 and the distal section 13 of the stent, and the metal wire frames 10 connected to the metal wire 201 are the metal wire frames 10 of the proximal section 11 and the distal section 13 of the stent near the middle section 12 of the stent; in addition, the two ends of the metal wire 201 can be also in anchoring connection with the tectorial membrane 30 of the stent proximal section 11 and the stent distal section 13; it should be noted that in some applications of the stent graft 100, the two ends of the wire 201 may not be sutured to the graft 30. In this embodiment, the wire 204 is wound along the axial direction of the stent graft 100, the winding direction is the circumferential direction of the stent graft 100, the number of winding turns of the wire 201 in the closed loop structure 20 is between 3 and 15, and the distance between two adjacent turns of the wire 201 is between 2 and 18; the distance between two adjacent spiral wires 201 can be adjusted, so that the branch bracket can be conveniently installed.

Referring to fig. 10b, in an alternative embodiment of the present invention, the middle section 12 of the bracket is formed by winding a metal wire 201, and the whole closed-loop structure 20 is in a ring shape; the metal wire 201 is wound along the circumferential direction of the covered stent 100 to form a metal ring 202, after the winding of the metal ring 202 is completed, the metal wire 201 is not cut off, the metal ring 202 is arranged along the axial direction of the covered stent 100, the distance between the two metal rings 202 is adjusted, and the operations are repeated, so that the whole closed ring structure 20 is laid; in this embodiment, the number of metal rings 202 in the closed ring structure 20 is between 3 and 15, and the distance between two adjacent metal rings 202 is between 1 and 20; the distance between two adjacent metal rings 202 can be adjusted to facilitate the installation of the branch support.

Referring to fig. 10c, in an optional embodiment of the present invention, the middle section 12 of the stent comprises a plurality of metal wires 201, each metal wire 201 is wound around the circumference of the stent graft 100 to form a closed metal ring 203, the plurality of closed metal rings 203 are arranged along the axial direction of the stent graft 100 at intervals, and the small curve of each closed metal ring 203 corresponding to the curved blood vessel is sewed with the stent graft 30 by medical suture or metal wire, two adjacent closed metal rings 203 are connected by a connecting rod 2031, two adjacent connecting rods 2031 are arranged in a staggered manner, the connecting rods 2031 on every two closed metal rings 203 are vertically opposite in the axial direction, the adjacent closed metal rings 203 are connected by a universal rod, which can play a role in stabilizing the structure, meanwhile, the adjacent closed metal rings 203 can be fixed at the connecting rod 2031, and the distance between the rest positions can be adjusted; and in this embodiment the number of closed metal loops 203 of the stent middle section 12 is between 3 and 15, wherein in this embodiment the number of closed metal loops 203 is 6.

Referring to fig. 10d and 10e, in an optional embodiment of the present invention, the middle section 12 of the stent is composed of a plurality of metal wires 201, each metal wire 201 is waved along the axial direction of the stent graft 100 while surrounding along the circumferential direction of the stent graft 100, so as to form a metal wave ring 204, and the plurality of metal wave rings 204 are arranged at intervals along the axial direction of the stent graft 100, and each metal wave ring 204 is sutured with the stent graft 30 through a medical suture or a metal wire corresponding to a small curve of a curved blood vessel. In this embodiment, the metal wave ring 204 also includes a peak 101', a valley 103', and two wave rods 102' connecting the peak 101' and the valley 103', one peak 101' and two adjacent wave rods 102' form a wave, the peak 101' and the valley 103' are relative, and the metal wave ring 204 is inverted in the axial direction, the peak 101' becomes the valley 103', and the valley 103' becomes the peak 101'; and each wave trough 103 'or wave crest 101' on the metal wave ring 204 and the small bend of the coating film 30 attached to the outer side of the stent graft 100 are sewn through medical sutures at multiple points, so that the whole closed ring structure 20 of the middle section 12 of the stent is in a grid shape or a wave shape, and the distance can be adjusted by shifting two adjacent metal wave rings 204, thereby facilitating the installation of the branch stent.

In this embodiment, the wave number of a wavy metal ring 204 is not fixed, and is set according to the value of the overall height of the closed loop structure 20 and the overall diameter of the wire framework 10. By way of example, the number of the undulating metal rings 204 of the stent mid-section 12 is between 3 and 12, and the wavenumber of one undulating metal ring 204 is between 3 and 12, wherein the number of undulating metal rings 204 is 4 in fig. 10d and 10e, and the wavenumber of undulating metal rings 204 is 3 in fig. 10 d; the wavenumber of the metal wave ring 204 in fig. 10e is 12. The radius R2 of the over-rounding between the peaks 101' or valleys 103' is in the range of 0-5mm, such as 0mm (corresponding to the case where two adjacent wave bars 102' are directly connected without over-rounding), 1mm, 2mm, 3mm, 4mm or 5mm. The R2 values of the metal wavy rings 204 are not necessarily the same, i.e. the peaks 101 'or the valleys 103' of the same metal wavy ring 204 may be the same or different. The magnitude of each R2 value should be set according to the requirements of the functions of the stent graft 100, such as later-stage crimping.

In this embodiment, the opening angle of the peak 101' (i.e., the included angle α 2 between two adjacent wave bars 102 ') is in the range of 10 ° -70 °, such as 10 °, 20 °, 30 °, 40 °, 50 °, 60 °, or 70 °, and the opening angles α 2 of the peaks 101' in the same metal wave ring 204 may be the same or different, and the value of each α 2 should be set according to the requirements of the post-crimping function of the stent graft 100.

Referring to fig. 11, in this embodiment, the wave bar 102' is a straight bar connecting the wave crests 101' and the wave troughs 103 '. The length L2 of wave bar 102 'ranges from 1-30mm, and the length L2 of wave bar 102' ranges from 1-30mm, such as 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, or 30mm. The lengths L2 of the wave bars 102' may be the same or different in the same metal wave ring 204. By way of example, the length L2 of all wave bars 102' of each metallic undulating ring 204 is shown in fig. 11 as being equal.

Referring to fig. 10f, in an alternative embodiment of the present invention, the middle section 12 of the stent is formed by a plurality of metal wires 201 wound into a plurality of metal wave rings 204. It should be noted that one undulating wire loop 204 may be divided into two wire segments of different wavelengths (i.e., two wire segments of different wavelengths on one closed loop), and each wire segment of different wavelengths occupies half of the stent middle section 12, wherein the wave number of one wire segment is between 1 and 4, and the wave number of the other wire segment is between 5 and 20; further, the wave numbers of the two wire segments in this example were 3 and 12, respectively; in actual assembly, the sections of the wires with smaller wavelength in the wavy metal rings 204 correspond to the small bends of the stent graft 100 in the bending state, and the peaks 101 'or the troughs 103' of the sections of the wires with larger wavelength in the wavy metal rings 204 are sutured with the stent graft 30 attached to the outer side of the stent graft 100 by medical sutures; the longer length of wire in the undulating metal ring 204 corresponds to the large curve in the curved state of the stent graft 100, which facilitates the bending of the stent graft 100 in the arch, while the large curve of the stent graft 100 has more adjustment space for the installation of the branch stent.

Referring to fig. 3 and 4, in the present invention, the cover 30 is one of the components constituting the stent graft 100, and the stent graft 100 may contain one cover 30. The cover film 30 is a layer of flexible film material attached to the wire frame 10 or the closed loop structure 20. The material of the cover film 30 may be PET (polyester fiber ) or EPTFE (polytetrafluoroethylene), for example. The cover film 30 is attached to at least one wire frame 10 or the closed loop structure 20 and at most to all of the wire frames 10 and the closed loop structure 20.

As shown in FIGS. 3 and 4, the placement of the stent graft 30 is optional and may be attached to different wire frames 10 of the stent graft 100 as desired. The coating 30 can be attached to the outer side, the inner side or both the inner and outer sides of the wire framework 10, and it should be noted that, for the middle section 12 of the stent, the coating 30 can only be wrapped on the outer side of the middle section 12 of the stent; the cover 30 may be attached to the wire frame 10 or the closed loop structure 20 by any suitable means such as adhesion (e.g., hot melt), sewing, etc., and in this embodiment, the cover 30 is attached to the outer side of the covered stent 100 and completely covers the stent proximal section 11, the stent middle section 12 and the stent distal section 13.

Referring to fig. 3 and 4, in the present invention, a tectorial membrane 30 with a completed structure is attached to the outer side wall of the tectorial membrane stent 100, and a tectorial membrane opening 301 is opened at a position of the tectorial membrane 30 corresponding to the middle section 12 of the stent, and the tectorial membrane opening 301 is opened along the axial direction of the tectorial membrane stent 100, the length thereof is slightly smaller than the length of the middle section 12 of the stent, suturing allowances 302 are left at both ends of the length direction of the tectorial membrane opening 301, and the suturing allowances 302 are reserved on one side opening wall or two side opening walls of the tectorial membrane opening 301, and are arranged along the radial direction of the middle section 12 of the stent, a suturing space is left for the operation suturing after the installation of the branch stent, thereby facilitating the operation of a doctor; the graft openings 301 may facilitate the reconstruction of the branch vessel (the reconstruction process includes in-situ windowing of the main stent graft 100; placing the branch stent graft 100 through windowing); it should be noted that when the stent intermediate section 12 of the stent graft 100 adopts the composite closed loop structure 20, the graft openings 301 correspond to the intersections of wire segments of two different wavenumbers.

Referring to fig. 3, in the present invention, the stent proximal section 11, the stent middle section 12 and the stent distal section 13 of the stent graft 100 have two states, i.e., a compression state and a release state. The compressed state is a state in which the stent graft 100 is compressed by a compression method of a common interventional stent (e.g., the stent graft 100 is compressed by a catheter) or a compression method of a common intraoperative stent (e.g., the stent graft is compressed by a pull rod and a binding wire); the released state is a state of the stent graft 100 at normal temperature of the human body when not constrained by external force. When the stent proximal section 11, the stent intermediate section 12, and the stent distal section 13 are present, the overall volume of the stent graft 100 is small, which may facilitate delivery of the stent graft 100 in a blood vessel. When the stent proximal section 11 and the stent distal section 13 are in the released state, the hollow cylindrical shape of the stent graft 100 can be maintained, the stent graft 100 is stably anchored on the inner wall of the blood vessel, the displacement of the stent graft 100 in the blood vessel is prevented, and the smooth flow of blood in the lumen of the stent graft 100 and the prevention of the blood stream from leaking outside the stent graft 30 are ensured. When the middle section 12 of the stent is in a release state, the covered stent 100 can be maintained to be tightly attached to the inner wall of the blood vessel; reconstructing the branch blood vessel through the axial opening on the tectorial membrane 30 (the reconstruction process comprises the in-situ windowing of the main body tectorial membrane stent 100; the placement of the branch tectorial membrane stent 100 through the windowing); when the branch artery covered stent 100 is placed, the branch stent can be implanted smoothly by adjusting the distance between the adjacent ring structures of the main stent arch; after the branch blood vessel reconstruction is completed, the stent middle section 12 enables the stent graft 100 in the branch blood vessel (branch artery stent graft 100) to be stably anchored on the inner wall of the blood vessel, prevents displacement of the stent graft 100 and the branch artery stent graft 100 in the blood vessel, ensures that blood flows smoothly in the lumens of the stent graft 100 and the branch artery stent graft 100, and ensures that the blood does not seep outside the stent graft.

When the stent graft 100 is used in an actual operation, first, an axial opening is cut in the aortic arch of a patient; subsequently, the stent graft 100 in a compressed state is delivered to the aortic arch region, and the stent intermediate section 12 is aligned with the branch vessel region; then, releasing the stent, and windowing the main body of the film-coated stent 100 (if windowing is performed, the step can be omitted); next, adjusting adjacent grids or screw rods in the middle section 12 of the bracket, vacating sufficient space for windowing, and installing a branch bracket; after the branch support is placed, adjusting the grids or the screw rods to press the tail ends of the branches, so that the anchoring performance of the branches is improved; finally, the aortic arch is sutured together with the axial opening of the stent graft 100 body.

To sum up, when the stent graft 100 of the branch artery is placed through the windowing of the stent graft 100 in the aorta, the stent graft 100 of the utility model can avoid the interference between the stent graft 100 system of the branch artery and the metal stent graft 100 in the aorta in the placing process; by adopting the closed loop structure 20 in the middle section 12 of the stent graft 100, the stent graft 100 can provide enough supporting force in the arch region, and the stent graft 100 in the branch blood vessel is prevented from being displaced into the aorta lumen while the aorta lumen is kept unobstructed. Therefore, the utility model effectively overcomes various defects in the prior art and has high industrial utilization value.

In the description herein, numerous specific details are provided, such as examples of components and/or methods, to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment of the invention can be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention.

It will also be appreciated that one or more of the elements shown in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed because it is not operational in certain circumstances or may be provided as useful in accordance with a particular application.

Additionally, any labeled arrows in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically noted. Further, as used herein, the term "or" is generally intended to mean "and/or" unless otherwise indicated. Combinations of components or steps will also be considered as being noted where terminology is foreseen as rendering the ability to separate or combine is unclear.

The above description of illustrated embodiments of the invention, including what is described in the abstract, is not intended to be exhaustive or to limit the invention to the precise forms disclosed herein. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention, as those skilled in the relevant art will recognize and appreciate. As noted, these modifications may be made to the invention in light of the above description of embodiments of the invention and are to be considered within the spirit and scope of the invention.

The system and method have been described herein in general terms as providing details to facilitate the understanding of the invention. Furthermore, various specific details have been given to provide a general understanding of the embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment of the invention can be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, materials, and/or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention.

Thus, although the present invention has been described herein with reference to particular embodiments thereof, freedom of modification, various changes and substitutions are also within the foregoing disclosure, and it should be understood that in some instances some features of the present invention will be employed without a corresponding use of other features without departing from the scope and spirit of the present invention as set forth. Accordingly, many modifications may be made to adapt a particular situation or material to the essential scope and spirit of the present invention. It is intended that the invention not be limited to the particular terms used in following claims and/or to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Accordingly, the scope of the invention is to be determined solely by the appended claims.

Claims (20)

1. A stent graft, comprising:

a scaffold, the scaffold divided into:

the stent comprises a stent proximal section and a stent distal section, wherein the stent proximal section and the stent distal section both comprise one or more metal wire frames which are arranged at intervals along the axial direction of the covered stent;

the middle section of the bracket comprises a closed ring structure consisting of one or more metal wires, and the closed ring structure is axially arranged between the proximal section of the bracket and the distal section of the bracket;

the film is fixedly connected with the stent proximal section and the stent distal section, and the middle part of the film is wrapped on the middle section of the stent;

and the film covering opening is arranged on the film covering and corresponds to the middle section of the stent, and a sewing allowance is reserved on the film covering opening.

2. The stent-graft of claim 1, wherein: the suture allowance is reserved on one side opening wall or two side opening walls of the tectorial membrane opening and is arranged along the radial direction of the middle section of the bracket for surgical suture.

3. The stent-graft of claim 1, wherein: the stent comprises a shape memory alloy stent.

4. The stent-graft of claim 1, wherein: the wire framework extends in the circumferential direction and undulates in the axial direction.

5. The stent-graft of claim 1, wherein: the metal wire frames are wavy or latticed, and the distances between every two adjacent metal wire frames are the same or different.

6. The stent graft as recited in claim 1, wherein: the metal wire frame comprises wave crests, wave troughs and wave rods connecting the wave crests and the wave troughs, and the wave rods are tangent or not tangent to the wave crests/the wave troughs.

7. The stent graft of claim 6, wherein: the axial positions of the wave crests and the wave troughs in each metal wire frame in the film-covered stent are opposite or staggered.

8. The stent-graft of claim 1, wherein: the wire frame of support proximal section, the closed loop structure of support interlude with the whole diameter of the wire frame of support distal section reduces in proper order or increases in proper order.

9. The stent-graft of claim 1, wherein: the closed ring structure comprises a metal wire which is wound in an axial spiral manner, and the two ends of the metal wire are respectively connected with the support telecentric section and the support telecentric section.

10. The stent-graft of claim 1, wherein: the closed ring structure comprises a metal wire, and the metal wire is wound at intervals along the axial direction to form a plurality of metal rings.

11. The stent graft of claim 9 or 10, wherein: and two ends of the metal wire are respectively connected with the metal wire frame or the film.

12. The stent graft as recited in claim 1, wherein: the closed ring structure comprises a plurality of metal wires, each metal wire is circumferentially arranged around a closed metal ring, the metal wires are axially arranged at intervals, and the metal wires are sewn with the film at small bent positions corresponding to the bending of the blood vessel.

13. The stent graft of claim 12, wherein: two adjacent seal metal rings are connected through connecting rods, two adjacent connecting rods are arranged in a staggered mode, and the axial positions of the connecting rods on the seal metal rings are the same at intervals.

14. The stent-graft of claim 1, wherein: the closed loop structure includes a plurality of wires, every when the wire centers on along circumference to be wavy along axial fluctuation, and many the wire is arranged along axial interval, the wire correspond the crooked little bend of blood vessel with the tectorial membrane is sewed up.

15. The stent-graft of claim 14, wherein: the metal wire comprises a wave crest, a wave trough and a wave rod connecting the wave crest and the wave trough, and the wave rod is tangent or not tangent with the wave crest/the wave trough.

16. The stent graft of claim 15, wherein: the axial positions of the wave crests and the wave troughs in two adjacent metal wires are opposite or staggered.

17. The stent graft of claim 15, wherein: the wire comprises two wire segments, and the two wire segments have different wavelengths.

18. The stent-graft of claim 17, wherein: the sections of the metal wires with smaller wavelengths correspond to small bends of the covered stent in the bending state, and the sections of the metal wires with larger wavelengths correspond to large bends of the covered stent in the bending state.

19. The stent-graft of claim 18, wherein: the wave crest or the wave trough in the metal wire section with the smaller wavelength in the metal wire is sewed with the covering film through a medical suture.

20. The stent-graft of claim 18, wherein: the opening position of the film covering opening on the film covering bracket corresponds to the junction of two metal wire sections in the metal wires.

Images