CN214180704U

CN214180704U - Intracavity implant structure and vena cava filter with same

Info

Publication number: CN214180704U
Application number: CN202021970384.7U
Authority: CN
Inventors: 沈斌; 赵向前; 陈奕龙; 吴梅周; 邱剑滔
Original assignee: Shenzhen Kyd Biomedical Technology Co ltd
Current assignee: Shenzhen Kyd Biomedical Technology Co ltd
Priority date: 2019-09-12
Filing date: 2020-09-10
Publication date: 2021-09-14
Anticipated expiration: 2030-09-10
Also published as: CN214180705U; CN114401695A; CN112120828A; CN214511417U; WO2021047604A1

Abstract

The utility model belongs to the technical field of implant medical instrument technique and specifically relates to a body structure is implanted to intracavity, especially relates to a vena cava filter, specifically discloses a body structure is implanted to intracavity and has the vena cava filter of structure, including the central part that has the central axis and the function portion that has the periphery that comprises a plurality of bars of central part outside extension, through the improvement to the range, structure and the shape of the pole that constitute function portion for the implant has better effects such as neutral.

Description

Intracavity implant structure and vena cava filter with same

Technical Field

The utility model belongs to the technical field of implant medical instrument technique and specifically relates to a body structure is implanted in intracavity, especially relates to a vena cava filter.

Background

An implantable medical device is a medical device that can be left in the body for a short or long period of time to support and sustain life, has a potential risk to the human body, and has to be strictly controlled in terms of safety and effectiveness. Expandable implantable medical devices such as vascular stents, vena cava filters, occluders, ventricular volume reduction devices, and the like, may be implanted into a body lumen via an interventional procedure by compressing to a very small volume, and the compressed device may be released and expanded at a desired location in the body to achieve a therapeutic effect, such as expansion, support, occlusion, volume reduction of a blood vessel or body lumen, or prevention of circulation of blood clots, and the like.

Whether temporary placement for a short period of time or long-term or lifetime implantation, strict requirements are imposed on the shape of the compressed intraluminally implanted device after release expansion in vivo, e.g. the longitudinal long axis of the implant should generally be kept in the center of the implanted body lumen, i.e. the implant has good neutrality, otherwise a reduction or loss of function of the implant may result.

However, good neutrality effects can be difficult to achieve. A typical case is a parachute-type vena cava filter, such as the Gunther Tulip manufactured and sold by William Cook^TMFilter and Celect^TMFilter, related documents such as US 5324304A. Such filters are mainly constituted by an umbrella filter portion, which is constituted by an array or weave of elongated supports, at least one end of which is gathered in the central position of the umbrella, in order to block the passage of the thrombus in the vein through the filter, and usually provided with a release or recovery portion, such as a recovery hook, for releasing or recovering the umbrella in cooperation with a sheath or the like. The parachute-shaped vena cava filter lacks effective limit near the recovery hook, and the filter is higher in probability of inclining during implantation and during implantation. The inclination of the filter is defined as the angle between the longitudinal axis of the filter and the central longitudinal axis of the vena cava>The serious inclination of the filter at 15 degrees causes the recovery hook to be attached to or adhered with the wall of the inferior vena cava, the umbrella shape is unfolded unevenly, and the serious events of incapability of recovering the filter, reduction of thrombus filtering effect, perforation and the like are caused. It is well documented that the cause of filter tilting may be related to factors such as aortic pulsation, gastrointestinal motility, the anatomical morphology of the inferior vena cava itself, and the location of the filter placement.

Improved filter constructions have been disclosed, for example in patent publications US20100049239a1, WO2018120414a1, CN105193521A, which add a stop mechanism near the recovery hook, with improved filter tilt and increased neutrality. However, these improved filter structures still have some drawbacks, such as that the limiting mechanism is usually formed by rods arranged near the filter, which can help to improve the neutralization effect when the rods are arranged longer or in a larger number, but at the same time, the difficulty of releasing the filter is increased remarkably, the resistance of the limiting mechanism in a compressed state when the limiting mechanism is released from the sheath tube is very large, the releasing operation in the body cavity is difficult to use a large force due to the fineness of the limiting mechanism, and the filter can not be realized when passing through a zigzag conveying cavity, and the requirement of a conveying system is high. On the other hand, the instant when the limiting mechanism is released from the sheath tube can generate a remarkable forward jump phenomenon, the cavity can be damaged by the impact similar to pumping out, and the final placement position and the posture of the filter cannot be effectively controlled.

However, reducing the number of rods or the length of the rods provides a low degree of support stability, such that neutral effects may not be achieved, for example the spacing mechanism rods may deflect sideways when pressed and lose spacing effect. Particularly typically, under the condition that the sheath tube and the cavity are not coaxial, the extension space and the compression force of the inner wall of the cavity are different when the rods in all directions of the limiting mechanism are released, and the probability of lateral deflection of the limiting mechanism rod close to one side of the inner wall of the cavity is higher. And, the bigger the distance between stop gear and the bottom end of the filter, i.e. the bigger the height of the filter, this phenomenon is more unavoidable.

Disclosure of Invention

The utility model provides an intracavitary implant structure and have the vena cava filter of structure, it has the characteristic of solving or improving one or more above-mentioned shortcomings at least.

One aspect of the present invention is to provide an endoluminal implant structure, including a central portion having a central axis and a functional portion having a periphery comprising a plurality of bars extending outwardly from the central portion, the functional portion periphery surrounding the central axis to be compressible.

The functional part can be at least used as a positioning structure of the implant, the functional part can be compressed to enable the functional part to have elasticity, and the implant can be anchored in a human body cavity, such as a blood vessel, by utilizing the elastic force of the functional part which tends to restore the uncompressed state when the functional part is in the compressed state. In the anchoring state, the central axis may be oriented in the central position of the body lumen, or the functional portion may conform to the body lumen shape.

At least one rod is provided with a bending part protruding towards the outer side direction of the functional part, the upper part and the lower part of the bending part are divided into an upper branch section and a lower branch section, the included angles of the upper branch section and the lower branch section are different from those of the central axis, the rod is further provided with a side branch section extending outwards at the bending part or the position near the bending part, and the farthest end of the side branch section, away from the central axis, is positioned between the tail end of the lower branch section and the bending part in a non-compression state.

In an embodiment of the present invention, the lateral branch section is coplanar with the central axis, two lower branch sections are drawn out below the bending portion, and the two lower branch sections are respectively located on two sides of the coplanar.

In an embodiment of the present invention, the extension direction of the upper branch section is greater than the included angle of the central axis, and the extension direction of the lower branch section is greater than the included angle of the central axis.

The utility model discloses an embodiment, the other branch section is including the crooked section of arc that upwards extends, the terminal deflection angle for its initiating terminal of the crooked section of arc is greater than 90 degrees.

In a preferred embodiment of the present invention, the curvature radius of the curved section increases gradually towards the end thereof.

In a preferred embodiment of the present invention, the lateral branch section further comprises a straight section, the straight section is substantially parallel to the lower branch section, the bent portion is led out, and the curved section is transited to.

In a preferred embodiment of the present invention, the number of the lower branch sections is at least two, and the straight sections located therebetween are arranged in the width direction of the rod.

In a preferred embodiment of the present invention, the portion of the curved segment near the end is substantially parallel to the central axis or is approximately parallel to the central axis.

The utility model discloses an embodiment, other branch section still includes the tail section, its by the end of the crooked section of arc is drawn forth, the tail section is directional the central axis direction, just the pole width of tail section is less than the pole width of other parts in the crooked section of arc.

The tail section may have a flanged spherical structure terminating in a spherical or spheroid-like body.

The utility model discloses a in some embodiments, the width of going up the section is greater than respectively the width of lower limb section and other limb section, the arc bending section of other limb section include basically with the parallel section that the central axis parallels to form the pressure with the coelomic wall and touch. The curvature radius of the arc-shaped bending section is gradually increased from the starting end to the tail end of the press-contacting section, a bent tail section extends towards the direction of the central part after the parallel section, and the width of the tail section is smaller than that of other sections in the side branch section. The variation in width can reduce the resistance to withdrawal of the rod into or out of the sheath, and the filter can be more easily handled in both withdrawal and withdrawal. The width of the tail section is processed, so that the bypass section can be effectively prevented from being stuck at the opening of the sheath when being recovered into the sheath, because the central axis of the central part of the filter implanted in the blood vessel is almost impossible to coincide with the central axis of the opening of the sheath when the filter implanted in the blood vessel is recovered, at least some bypass sections are necessarily collected into the opening of the sheath in an inclined posture, and the phenomenon that the bypass section is stuck at the opening of the sheath is high.

In an alternative embodiment of the present invention, the endoluminal implant structure may further comprise one or more of the following structural features:

the structure I is characterized in that the straight section and the central axis form an included angle;

a second structure, wherein the arc-shaped bent section is internally provided with a lowest point along the direction of the central axis, and the lowest point is positioned between the near end and the far end of the arc-shaped bent section;

and in a third structure, the deflection angle of the far end of the arc-shaped bent section relative to the near end of the arc-shaped bent section is not more than 180 degrees.

And in a fourth structure, the deflection angle of the far end of the bypass section relative to the near end of the bypass section is larger than 180 degrees.

In an alternative embodiment of the present invention, the rods constituting the functional part are not fixedly connected to each other.

It is another aspect of the present invention to provide a vena cava filter having an endoluminal implant structure as described above.

Wherein, each rod of function portion evenly distributes along circumference for block the thrombus in the vena cava passes through the function portion.

In an embodiment of the present invention, each rod of the functional portion respectively leads out two lower branch sections extending in opposite directions at the bending portion, and when in a compressed state, the two lower branch sections adjacent to each other or cross each other between the adjacent rods, so that the functional portion forms a mesh structure.

The two lower branch sections can improve the supporting performance of the periphery, and the lower branch sections are staggered with the side branch sections, so that the release resistance of the rod can be reduced. The filter can take place endothelialization phenomenon after implanting a period of time in the blood vessel, and the endothelium climbs the pole of covering the implant for the filter is retrieved the degree of difficulty and is big, retrieves the damage increase to the blood vessel, can not retrieve even. The two lower branch sections are not fixedly connected, so that the lower branch sections have larger freedom degree, and are easier to extract from endothelial tissues, the damage to blood vessels is reduced, and meanwhile, the contact of the two lower branch sections can also improve the support capability and the shape stability of the rod, so that the filter can be more stably kept at the position released by a fixed point in the blood vessel according to the required shape, and the filter is prevented from migrating.

In one embodiment of the present invention, when in the non-compressed state, two adjacent lower branch sections between the adjacent rods are offset away from the end thereof.

In another aspect of the present invention, there is provided a structure of an endoluminal implant or an endoluminal implant having the same, which includes a central portion having a central axis and a functional portion having a periphery and formed by a plurality of rods extending outwardly from the central portion, wherein the functional portion is compressible.

The utility model relates to an intracavity implant structure, when non-compression state, the functional part includes at least the first periphery, the second periphery and the third periphery that are formed by the flange or the free end of a plurality of poles surrounding the central axis arrangement, the first periphery, the second periphery and the third periphery are arranged outwards from the central part in proper order and are not coplanar with each other, the first periphery and the second periphery are closer to the central part than the third periphery along the central axis direction;

the flange or free end of the rod may be pressed to move towards the central axis, and the second and third peripheries may be pressed to positionally retain the implant in a first position within the cavity in which it is implanted;

any one or more of the flanges or free ends forming the first outer perimeter, when compressed, may cause the implant to be positionally retained towards the first position within the cavity in which it is implanted.

Obviously, said flange is meant to be directed towards the outer side of said functional part, in order to provide a possible support site in the anchored state of the implant.

The second periphery and the third periphery form two layers of supporting sites distributed along the long axis direction of the cavity of the functional part, can be contacted with the inner wall of the cavity implanted by the implant, and relative to the non-compressed state, the second periphery and the third periphery are pressed by the inner wall of the cavity, can resist the inclination of the central part or the central axis to the direction of the inner wall of the cavity, keep a certain distance between the central part and the inner wall of the cavity, and form a desired first posture. When the support of the flange or free end of any one or more of the rods of the second periphery is lost due to various factors, such as the flange or free end being displaced laterally thereof and the support being lost or weakened, the flange or free end of the rod of the first periphery in the vicinity of the support site may abut against the inner wall of the cavity to form a second posture, the central portion is prevented from adhering to the wall against the inclination of the central portion or said central axis to the direction laterally of the displaced support site to the inner wall of the cavity, i.e. the implant may try to maintain the second posture towards the first posture.

In one embodiment, the number of flanges or free ends forming the first periphery is not less than the number of flanges or free ends forming the second periphery, and at least one to one. Wherein the flange or free end constituting the first outer periphery and the corresponding flange or free end constituting the second outer periphery may be located substantially in the same radial direction. For example, a preferred embodiment of the one-to-one correspondence may mean that one flange or free end constituting the first outer periphery and the other flange or free end constituting the second outer periphery corresponding thereto are substantially in the same radial direction.

In one embodiment, the first outer periphery is located between the second outer periphery and the third outer periphery in the direction of the central axis. Or the second outer periphery is located between the first outer periphery and the third outer periphery in the central axis direction.

In one embodiment, the first outer periphery is formed by a flange of the rod.

Alternatively, either periphery may optionally be formed by a flange or free end. For example, both the third outer periphery and the second outer periphery are constituted by the free end, or the third outer periphery is constituted by the free end and the second outer periphery is constituted by the flange.

The rods constituting the outer periphery may include at least a first array rod and a second array rod.

In one embodiment, the third perimeter is formed by an arrangement of free ends of the first array of rods and the second perimeter is formed by an arrangement of free ends or flanges of the second array of rods.

In one embodiment, the third periphery is formed by an arrangement of free ends of the first array of stems, the first array of stems further being provided with branches, and the second periphery is formed by an arrangement of free ends or flanges of the branches of the first array of stems.

In a further development, the first array of rods is further provided with a flange, the first periphery being constituted by the flange of the first array of rods. For example, the first array rods each have a bent portion, the first array rods form an included angle at the bent portion at a front section and a rear section of the respective bent portion, and the bent portions of the first array rods form the flange.

In one embodiment, the rod forming the free end or flange of the second periphery has a curved section extending in a direction away from the third periphery, the terminal or projecting end of the curved section forming the free end or flange of the second periphery.

Preferably, the second outer periphery is radially close to the first outer periphery.

Optionally, the first periphery, the second periphery and the third periphery are all located on the same side of the central portion.

Preferably, the flange or the free end has a smoothly curved surface, and can be brought into contact with the inner wall of the cavity in which the implant is implanted through the smoothly curved surface.

Preferably, the number of flanges or free ends constituting the third outer periphery is greater than the number of flanges or free ends constituting the second outer periphery.

In a further improvement, the number of the flanges or free ends constituting the third outer periphery is twice the number of the flanges or free ends constituting the second outer periphery, and the flanges or free ends constituting the third outer periphery are distributed in pairs, each pair of the flanges or free ends constituting the third outer periphery and the flanges or free ends constituting the second outer periphery being distributed in a staggered manner in the circumferential direction of the central axis.

Preferably, each rod of the functional part is made by integrally cutting a pipe and then shaping.

The utility model discloses a vena cava filter with the intracavity implant structure as described above, wherein the function portion comprises a plurality of rods, and the rods are evenly distributed along the circumferential direction and are used for blocking thrombus in the vena cava to pass through the function portion.

In another aspect of the present invention, there is provided a recoverable endoluminal implant structure or a recoverable endoluminal implant having the same, comprising a central portion having a central axis and a functional portion formed by arranging the central axis and surrounded by a plurality of rods extending outwardly from the central portion, wherein the implant is positioned and held by compression of the functional portion through an endoluminal wall in an implanted chamber of the implant.

Wherein at least one rod includes an arcuate curved segment having a radius of curvature that increases from its proximal end proximate the central portion to its distal end.

In one embodiment of the utility model, the curvature radius is gradually increased, the curved section of the arc tends to be straight more to the far end direction, and the resistance when the sheath pipe is recovered is also smaller.

In one embodiment of the present invention, the curved segment is substantially parallel to the central axis or is nearly parallel to the central axis near its distal end.

In one embodiment of the present invention, the rod further continues to have a tail section extending from the distal end of the curved section.

In an embodiment of the present invention, the tail section is parallel to the central axis or is bent toward the central axis.

In one embodiment of the present invention, the end of the rod is a sphere or a similar sphere having a flange spherical structure.

In one embodiment of the present invention, the rod as a whole tends to decrease in width toward its distal end.

In one embodiment of the present invention, the diameter of the terminal sphere or similar sphere of the rod is greater than the rod width of the segment adjacent thereto. For example, the rod width of the tail section is less than the rod width of the arcuate bend section.

The utility model discloses an embodiment, the pole is in the proximal end side of arc bending section still is provided with straight section, the pole is extended by straight section the arc bending section, straight section with the central axis is the contained angle.

In one embodiment of the present invention, the curved section has a lowest point along the central axis, the lowest point is located between the proximal end and the distal end of the curved section.

In one embodiment of the present invention, the distal end of the curved segment is angled more than 90 degrees relative to its proximal end.

It is another aspect of the present invention to provide a vena cava filter having the above-described recoverable endoluminal implant structure.

In summary, the preferred or preferred embodiment of the present invention, the endoluminal implant structure and the vena cava filter having the same, can have good neutrality, transportability, safety, and ease of operation.

The embodiment of the utility model provides an in, intracavity implant or vena cava filter can regard as the recoverable apparatus, can have longer implantation period, the success rate of retrieving is higher, to the low equivalent effect of the damage of vena cava.

Drawings

FIGS. 1 and 2 are schematic views of a single rod of two embodiments of implant structures of the present invention;

FIGS. 3-9 are schematic views of two symmetrical rods of different implant configuration embodiments of the present invention;

FIGS. 10-12 are views along the central axis of three embodiments of the implant structure of the present invention;

FIGS. 13 and 14 are schematic views of a preferred embodiment of the vena cava filter of the present invention in different orientations, respectively;

FIG. 15 is an enlarged view of a portion of FIG. 13;

FIGS. 16 and 17 are two different graphs illustrating the effect of a preferred embodiment of a vena cava filter of the present invention after release from the implanted chamber;

fig. 18 and 19 are finite element analysis graphs of two examples of vena cava filters simulating forces after implantation in a lumen, respectively.

In the finite element analysis diagrams shown in fig. 18 and 19, the stress levels of different positions of the vena cava filter are distinguished by colors, the minimum stress area is marked by blue, the maximum stress area is marked by red, the middle stress area is shown by transition color gradient, for example, the stress of the corresponding stress area is gradually increased from small to large, and the corresponding position area of the vena cava filter is sequentially shown by blue, green, yellow, orange and red. In fig. 18, the filter is shown with the greatest force area near the root of the side branch segment, which is shown as orange or red, with a gradual decrease in force from the end of the side branch segment leading from the superior segment toward the end of the side branch segment, and with a portion of the side branch segment near the root having an orange or yellow color that is significantly more force-bearing than the remainder of the vena cava filter (blue or green). In fig. 19, the area of the filter with the greatest stress is not located at the root of the bypass section, but is located near the bottom of the bypass section, i.e., near the position of the bypass section farthest from the root of the bypass section along the central axis of the filter, and the area with the greatest stress of the filter is mainly green, and has no red or orange area, and other parts of the vena cava filter are blue or green, especially the bending part of the upper bypass section and the root of the bypass section are blue or green, and the display stress is small.

In the drawings, reference numerals are explained as follows:

1. a central portion; 2. a first array of rods; 21. an upper branch section; 211. a bending part; 22. 221, 222, a lower support section; 23. a bypass section; 31. a first outer periphery; 32. a second outer periphery; 33. a third outer periphery; 4. a second array bar; 5. the inner wall of the cavity.

Detailed Description

One type of prior art endoluminal implant structure includes a central portion having a central axis and a functional portion having a periphery formed by a plurality of bars extending outwardly from the central portion, the functional portion periphery surrounding the central axis and being compressible by the luminal inner wall toward the central axis such that the implant is positionally retained within the lumen in which it is implanted. A typical such implant structure is described in WO2017186025a1 by the present inventors and incorporated herein in its entirety. The implant in the strong compression state has small shape and volume and can be placed in the sheath tube and conveyed in the cavity of the human body through the sheath tube, the implant is released from the sheath tube at the position where the implant is required to be placed through the operation of an operator, the implant in the strong compression state expands and tends to the non-compression state, the functional part rod of the implant is far away from the central axis and expands and presses against the inner wall of the implanted cavity, the plurality of rods support the circumferential direction of the implant, and the functional part expands and keeps in the weak compression state relative to the strong compression state so as to position and keep the implant in the implanted cavity.

However, the above description is not limiting, and the endoluminal implants disclosed in, for example, CN1399530A, CN1842354A, CN105208947A, etc. have similar structures.

The embodiments of the present invention will be described in further detail with reference to the accompanying drawings and detailed description.

Endoluminal implant Structure

It is an object of the present invention to provide an improved endoluminal implant structure, wherein in a non-compressed state, the functional portion comprises at least a first periphery 31, a second periphery 32 and a third periphery 33, which are formed by arranging flanges or free ends of a plurality of rods around a central axis, the first periphery 31, the second periphery 32 and the third periphery 33 are sequentially arranged outward from the central portion 1 and are not coplanar with each other, the first periphery 31 and the second periphery 32 are closer to the central portion 1 than the third periphery 33 along the central axis;

the flange or free end of the stem may be pressed to move towards the central axis, and the second outer periphery 32 and the third outer periphery 33 may be pressed to hold the implant in a first position within the cavity in which it is implanted;

any one or more of the flanges or free ends forming the first outer perimeter 31, when compressed, will allow the implant to be held in position as it approaches the first position within the cavity in which it is implanted.

Wherein the flange faces in an outer direction of the functional portion.

The embodiment of the utility model provides a flange can be for the portion 211 of bending of pole, towards the outside direction of functional portion, refer to fig. 1-9, also can be for the curved section distance of arc the most distal end of central axis refers to the section that the curvature radius of fig. 15 is D2. However, without limitation, one skilled in the art may select other types of flanges that may serve as support sites for the implant to position and support in contact with the inner walls of the implanted cavity. The flange is preferably the bending part 211 of the rod, and referring to fig. 1-9 or fig. 13, the bending part 211 has a non-arc bending, so that the rod forms a relatively fixed included angle above and below the bending part 211, which makes it possible to reduce the transmission of the compressive force to the root of the rod when the end of the rod is pressed by the inner wall of the cavity, because the included angle of the bending part 211 can be reduced due to the pressing of the end of the rod, which plays a role in buffering or reducing the force transmitted to the root of the rod. Meanwhile, the lower leg of the rod led out below the bending part 211 provides the tail end of the rod, and the lower leg has greater elastic restoring force due to the smaller included angle of the bending part 211, thereby providing stronger support and positioning for the implant in the implantation cavity.

With continued reference to fig. 15 and 16, the segment having a radius of curvature D2 may be a press-contact segment substantially parallel to or inclined to be parallel to the central axis and may be in press-contact with the inner wall of the implanted cavity to support or bolster the positioning of the implant. The curvature radius of the whole arc-shaped bending section is gradually increased from the starting end to the tail end of the pressing contact section. The inclined part is parallel to the central axis, and the included angle between the press contact section which can be basically a straight line and the central axis is not more than 15 degrees. This kind of setting, when the implant was retrieved, the pressure was touched the section and was taken in and retrieve the sheath pipe, reduced the body cavity inner wall, retrieve the recovery resistance to implant deformation that the sheath mouth produced, when being favorable to implanting state again, the pressure touched the section and provides the contact with the great area of body cavity inner wall, improved the stable effect of anchoring.

Referring to fig. 10-12, three implant structural embodiments of the present invention are shown, each having a first outer perimeter 31, a second outer perimeter 32, and a third outer perimeter 33 of the flange or free end of the stem, with radii a, b, and c in that order. The shape of each rod constituting the functional part of the implant of fig. 12 may be any one of fig. 7 to 9, and the shape of each rod constituting the functional part of the implant of fig. 10 and 11 may be any one of fig. 1 to 6. The main difference between the implant functions of fig. 10 and 11 is the number and shape of the lower branch of the stem.

The second outer periphery 32 and the third outer periphery 33 constitute two layers of support sites of the functional part distributed along the long axis direction of the cavity, and can be contacted with the inner wall of the cavity implanted by the implant, and the second outer periphery 32 and the third outer periphery 33 can resist the inclination of the central part 1 or the central axis to the direction of the inner wall of the cavity by the pressure of the inner wall of the cavity in a non-compressed state, and keep a certain distance between the central part 1 and the inner wall of the cavity to form a desired first posture. When the support of the flange or free end of any one or more of the rods of the second outer circumference 32 is lost due to various factors, for example, the flange or free end is shifted to the side thereof and the support thereof is lost or weakened, the flange or free end of the rod of the first outer circumference 31 in the vicinity of the support site may abut against the inner wall of the cavity to form a second posture, and the central portion 1 is prevented from abutting against the cavity wall against the inclination of the central portion 1 or the central axis to the side of the shifted support site of the inner wall of the cavity, that is, the implant may maintain the second posture as close to the first posture as possible.

However, the above description is not restrictive, and the implant can directly assume the second posture after being released through the sheath in the cavity, but not assume the first posture, and in this case, the first posture can be the ideal implant implantation state desired by the operator. For example, the implant is released in the case of poor overlap of the sheath with the cavity along the long axis.

As a non-limiting example, another possibility is that peristaltic movement, contraction, etc. of the cavity causes a change in the position or shape of the implanted implant from an initial first posture to a second posture.

Fig. 13 and 14 show a preferred embodiment of the implant of the invention, with a top view along the central axis of the central part 1 similar to fig. 11, with three peripheries, fig. 16 and 17 showing two positions of the implant in the implanted cavity, fig. 16 showing the position of the implant generally desired, fig. 17 showing at least one of the support sites of the second periphery 32 being disabled by lateral offset, and the bent portion 211 of the rod constituting the first periphery 31 in its vicinity acting as a support site, avoiding a more excessive tilt of the central part 1 or central axis, keeping the central part 1 at a suitable distance from the cavity wall.

As a preferred embodiment, the number of flanges or free ends constituting the first periphery 31 is not less than the number of flanges or free ends constituting the second periphery 32, and at least one-to-one correspondence. Fig. 10 and 11 show a corresponding manner in the radial direction of the periphery, in which the number of flanges or free ends constituting the first periphery 31 is equal to the number of flanges or free ends constituting the second periphery 32, and the two corresponding flanges or free ends of the periphery are located in substantially the same radial direction, which gives the first periphery 31 a better complementary support effect for the support sites, a more precise complementary support for the failure sites of the second periphery 32, and a smaller angle of inclination of the filter which can thus be controlled. Fig. 12 shows another non-radial correspondence between the flanges or free ends of any two adjacent second peripheries 32 for a flange or free end of a first periphery 31. Wherein the number of flanges or free ends of the first outer circumference 31 is equal to the number of flanges or free ends of the second outer circumference 32 in fig. 10-12.

As a preferred embodiment, the first periphery 31 is located between the second periphery 32 and the third periphery 33 in the direction of the central axis, see the distribution of the respective peripheral radii shown in fig. 1 and 2. In other alternative embodiments, the second outer periphery 32 is located between the first outer periphery 31 and the third outer periphery 33 in the direction of the central axis, such as in fig. 5.

The third, second and

first peripheries

33, 32, 31 may each be constituted by free ends of bars, for example of the first, second and third array bars 2, 4, respectively.

In a preferred embodiment, the first periphery 31 is constituted by a flange of the rod, the third periphery 33 and the second periphery 32 are constituted by free ends, or the third periphery 33 is constituted by a free end and the second periphery 32 is constituted by a flange. For example, the third outer periphery 33 is formed by an arrangement of free ends of the first array of rods 2 and the second outer periphery 32 is formed by an arrangement of free ends or flanges of the second array of rods 4, each of which may have the shape of any of FIGS. 7-9, with reference to FIG. 12; for another example, the third outer periphery 33 is formed by an arrangement of free ends of the first array rod 2, the first array rod 2 is further provided with branches, the second outer periphery 32 is formed by an arrangement of free ends or flanges of the branches of the first array rod 2, and referring to fig. 10 or 11, the shape of the first array rod 2 and its branches may be any of fig. 1-9.

Wherein the first array bar 2 may also be provided with a flange, the first periphery 31 being constituted by the flange of the first array bar 2. For example, the first array rods 2 each have a bending portion 211, the first array rods 2 form an included angle at the bending portion 211 at the front and rear sections of the respective bending portion 211, and the bending portions 211 of the first array rods 2 form a flange, refer to fig. 1-6.

Wherein the free end or flange forming the second periphery 32 is provided in the stem with a curved section extending in a direction away from the third periphery 33, the end or protruding end of the curved section forming the free end or flange of the second periphery 32. Referring to fig. 1 to 4 and 6, the first array rod 2 has branches from the upper branch section 21 to extend the lower branch section 22 and the side branch section 23, wherein the side branch section 23 has a bent section, and the second outer circumference 32 may be formed by an end of the bent section as a free end or by an outermost protruding end of the bent section as a flange according to the shape of the bent section.

In a preferred embodiment, the second outer periphery 32 is radially close to the first outer periphery 31. I.e. the distance in the radial direction between the first 31 and second 32 outer peripheries may be smaller than the distance in the radial direction between the second 32 and third 33 outer peripheries.

Alternatively, the first 31 and second 32 peripheries are located on either side of the central portion 1 and the third periphery 33 is located on one of the sides. Preferably, however, the first 31, second 32 and third 33 peripheries are all located on the same side of the central portion 1.

In a preferred embodiment, either the flange or the free end has a smooth curved surface and can contact the wall of the lumen in which the implant is implanted via the smooth curved surface.

In a preferred embodiment, the number of flanges or free ends constituting the third outer periphery 33 is greater than the number of flanges or free ends constituting the second outer periphery 32. For example, in the implant shown in fig. 11, the first array rod 2 is divided into two

lower branch sections

221, 222 from the bending part 211, and the adjacent lower branch sections of two adjacent first array rods 2 can be in contact with each other but not fixedly connected with each other, refer to fig. 12, 16 or 19. At this time, the number of the flanges or free ends constituting the third outer periphery 33 is twice the number of the flanges or free ends constituting the second outer periphery 32, and the flanges or free ends constituting the third outer periphery 33 are distributed in pairs of two by two, each pair of the flanges or free ends constituting the third outer periphery 33 and the flanges or free ends constituting the second outer periphery 32 being distributed alternately in the circumferential direction of the central axis, see fig. 14.

The utility model discloses each pole of implant function portion is preferably made through the setting after the integrative cutting of tubular product. The tubular product can be made of shape memory materials such as stainless steel, nickel-titanium alloy and the like, and the design shape of the non-compression state is obtained through heat setting.

A rod constituting the functional part

The utility model discloses in the partial implant embodiment, among a plurality of poles that constitute the functional part, at least one pole is equipped with the portion 211 of bending that is outstanding to the outside direction of functional part to be divided into the last section 21 and the lower section 22 that differ with the contained angle of central axis in the top and the below of the portion 211 of bending, the pole still is equipped with the other section 23 of branch that outwards stretches out near the portion 211 of bending or the portion 211 of bending, during the non-compression state, the most remote end of other section 23 distance central axis is located between the end of lower section 22 and the portion 211 of bending.

Taking fig. 1 and 2 as an example, two types of rods constituting the functional part are shown, in which the distance from the central axis of the aforementioned farthest end of the side branch 23 is b, the distance from the central axis of the bent part 211 is c, and the distance from the central axis of the end of the lower branch 22 is a, and it is apparent that a > b > c in the non-compressed state. The side branch section 23 in this embodiment includes an upwardly extending arcuate curved section. The flange formed at the tail end or the outermost side end of the arc-shaped bending section can be propped against the inner wall of the implanted cavity body in the cavity to play a supporting role.

The rod with the bending part 211 is implanted in the cavity, and two support points with functional parts distributed along the long axis direction of the cavity are formed by the most far end of the side branch section 23 and the tail end of the lower branch section 22, so as to resist the inclination of the central part 1 to the side direction of the rod on the inner wall of the cavity and keep a certain distance between the central part 1 and the inner wall of the cavity, as shown in the embodiment of fig. 12.

When the side branch 23 is in its non-compressed state, laterally influenced by various factors, and its function as a support point may be lost, the bent portion 211 of the rod may abut against the inner wall of the cavity to resist the inclination of the central portion 1 toward the inner wall of the cavity in the direction of the side on which the rod is located. At this time, the bending part 211 and the lower section 22 can be integrally abutted against the inner wall of the lumen, the support area of the rod is increased, the support of the functional part is more stable, but the unit pressure to the inner wall of the lumen is weak, so that the inner wall of the blood vessel can be prevented from being crushed or punctured, see the embodiment of fig. 17.

The side branch section 23 can be arranged to be led out from the bent part 211 of the rod, see fig. 1 and 5, the side branch section 23 shown in fig. 1 is an arc-shaped bent section extending upwards, and the side branch section 23 shown in fig. 5 is a straight section extending downwards.

Alternatively, the bypass portion 23 is provided so as to be drawn out from the vicinity of the bent portion 211 of the lever.

In one embodiment, the side branch section 23 is derived from the upper branch section 21. referring to fig. 2 and 4, the side branch section 23 shown in fig. 2 may be an upwardly extending arcuate curved section, and the side branch section 23 shown in fig. 4 is a downwardly extending arcuate curved section.

In another embodiment, a bypass leg 23 may be provided from the lower leg 22, see fig. 3 and 6.

Those skilled in the art can select different styles of the side branch sections 23 according to the needs, and the invention is not limited to the embodiment of the invention.

The structure and shape of the rod shown in fig. 6 is a preferred embodiment, the rod having an upper leg 21 leading from the central portion 1 and a lower leg 22 leading via a bend 211. The side branch section 23 is led out from the lower branch section 22 and comprises an arc-shaped bent section. The end of the side branch section 23 is deflected by an angle of more than 180 degrees with respect to its starting end, and its end points in the direction of the central axis.

In a further preferred embodiment, the curved section has a radius of curvature which increases towards its end. Referring to fig. 13 and 15, the curved section in fig. 15 is formed by three sections, and the radius of curvature of the curved section is sequentially D1, D2 and D3, and the curved section is sequentially increased, so that the side branch section 23 can be attached to the vessel wall as much as possible. On the one hand, the side branch 23 may have a shorter length than the central portion 1, leading from the vicinity of the bent portion 211, and thus may have a greater resistance to deflection, and on the other hand, the gradual increase in the radius of curvature may cause the side branch 23 to contact the blood vessel wall in a line contact rather than a point contact.

The flange formed at the tail end or the outermost side end of the arc-shaped bending section can be propped against the inner wall of the implanted cavity body in the cavity to play a supporting role. The rod with the bending part 211 is implanted in the cavity, and two support points with functional parts distributed along the long axis direction of the cavity are formed by the most far end of the side branch section 23 and the tail end of the lower branch section 22, so as to resist the inclination of the functional parts to the side direction of the rod on the inner wall of the cavity and keep a certain distance between the central part 1 and the inner wall of the cavity, as shown in the embodiment of fig. 16. When the side branch section 23 is in its side of non-compressed state, which is affected by various factors, its function as a support point may be lost, and the bent portion 211 of the rod may abut against the inner wall of the cavity to resist the inclination of the functional portion to the inner wall of the cavity in the direction of the side of the rod. At this time, the bending part 211 and the lower section 22 can be integrally abutted against the inner wall of the lumen, the support area of the rod is increased, the support of the functional part is more stable, but the unit pressure to the inner wall of the lumen is weak, and the inner wall of the blood vessel can be prevented from being crushed or punctured, see the embodiment of fig. 17.

In a further improvement, referring to fig. 13 and 15, the side branch segment 23 further includes a straight segment L, and the straight segment is substantially parallel to the lower branch segment 22, led out by the bending portion 211, and transited to an arc-shaped bending segment. The lower branch section 22 may be one, two or more, and may be set as required by those skilled in the art. When there are at least two lower branch sections 22, in a preferred embodiment, the side branch section 23 is located between the two

lower branch sections

221, 222, and the straight section and the lower branch section of the side branch section 23 are aligned in the pole width direction.

Based on the above description, the side branch section 23 may be selected to be coplanar or non-coplanar with the central axis. The non-coplanar bypass sections 23 may be more difficult to release and retrieve.

The side branch 23 is shown in figure 10 to be coplanar with the central axis, with the bend 211 of the bar in which the side branch 23 is located leading out of the lower branch 22. The side branch section 23 shown in fig. 11 is coplanar with the central axis, two

lower branch sections

221, 222 are led out from the bending part 211 of the rod where the side branch section 23 is located, and the two

lower branch sections

221, 222 are respectively located on two sides of the coplanar.

The implant functional part of fig. 10 and 11 has the third outer circumference 33 formed by the ends of the lower branch sections of 6 first array rods 2 arranged at equal intervals around the central axis, the second outer circumference 32 formed by the farthest ends of the side branch sections 23 of 6 first array rods 2 arranged at equal intervals around the central axis, and the first outer circumference 31 formed by the bent sections 211 of 6 first array rods 2 arranged at equal intervals around the central axis. Whereas the implant function of fig. 12 is composed of 6 first array rods 2 alternating circumferentially with 6 second array rods 4.

In the uncompressed state, the diameter of the third outer periphery 33 is preferably 1.5 to 4 times the diameter of the second outer periphery 32, and the second outer periphery 32 is radially closer to the first outer periphery 31.

The upper leg section 21 and the lower leg section 22 may have a bend or bend. The

lower leg sections

221, 222 shown in figures 11, 13, 14 each have an S-shaped curved section.

Wherein the implant of fig. 10 has 6 inferior branch ends, while the implant of fig. 11 may have 6 or 12 inferior branch ends. Alternatively, two adjacent rods of the implant of fig. 8 are butted or crossed by two adjacent lower branch sections, so that the functional part forms a net structure, but 12 of the ends are kept as free ends, see fig. 13 and 14. Alternatively, however, each two adjacent rods of the implant of fig. 8 are fixed at one end by the convergence of two adjacent lower leg segments, so that the implant can have 6 such ends.

On the basis of the above description, the preferred embodiment of the present invention, referring to fig. 1 and fig. 2, the included angle α between the extending direction of the upper branch section 21 and the central axis is larger than the included angle β between the extending direction of the lower branch section and the central axis. Such a construction may have a relatively small height (i.e. length along the central axis) given the maximum circumference of the functional part, which may be very advantageous in most cases.

The width of the functional part rod of the present invention is preferably reduced from the central part 1 to the outside as a whole.

For example, the width of the superior branch 21 is greater than the inferior branch 22 (or 221, 222) and the lateral branch 23.

In a further preferred embodiment, the width of the side branch 23 decreases overall from its starting end to its end. For example, the side branch section 23 is divided into two sections different in width from the bottom of the upwardly extending curved section. The tail end of the rear half section with narrower width can be provided with a round head similar to a sphere, so that the inner wall of the cavity can be prevented from being punctured.

The utility model discloses the length of preferred upper branch section 21 is far less than the length of lower branch section 22 (or 221, 222), and its length ratio can be in 0.2-0.05.

The preferred end of the side branch 23 of the present invention is located at or near the central portion 1 along the central axis.

Vena cava filter

Another aspect of the present invention is to provide a vena cava filter having any one of the above-mentioned intracavity implant structures, wherein the respective rods of the functional part are uniformly distributed along the circumferential direction, so as to block the thrombus from passing through the functional part in the vena cava.

Referring to fig. 10-12, three vena cava filters are shown.

Fig. 13 and 14 show a preferred vena cava filter according to the present invention, each rod of the functional portion has two oppositely extending

lower branches

221 and 222 respectively led out from the bending portion 211, and when in a compressed state, the adjacent rods are abutted or crossed by the adjacent two lower branches, so that the functional portion forms a net structure, see fig. 16, 17 and 19.

Optionally, in the non-compressed state, two adjacent lower branch sections between adjacent rods are abutted away from the ends thereof, and the two lower branch sections are parallelly gathered from the abutted points to the ends, see fig. 13 and 14.

The utility model discloses the other branch section 23 of preferred vena cava filter embodiment is drawn forth by portion 211 of bending, and draws forth earlier for the straight section that is basically parallel with lower branch section retransforms the arc bending section that becomes curvature radius gradually bigger and bigger gradually, and the terminal deflection angle for its initiating terminal of arc bending section is greater than 180 degrees, and the directional central axis direction of its terminal. The side branch section 23 is located between the two

lower branch sections

221, 222, and the straight section of the side branch section 23 and the lower branch section 22 are arranged in the rod width direction.

Under the same condition, compare in the comparison vena cava filter that does not have the portion of bending and the lower limb is direct to draw forth other branch section 23 and is the arc bending section, the utility model discloses preferred vena cava filter embodiment has more excellent structural mechanics, and stress is whole to be reduced, and stress distribution is more even, see fig. 18 and fig. 19, fig. 19 shows the utility model discloses preferred vena cava filter embodiment obviously reduces at the stress of other branch section 23 root (being the initiating terminal), and does not have stress concentration region at this root, compares in the comparison example shown in fig. 18, both can show to reduce other branch section 23 at the cracked risk of root, and lower stress is favorable to the compression and the recovery of other branch section 23 simultaneously, avoids the jump ahead or reduces and retrieves the resistance, and operability and security improve by a wide margin.

The above is to the utility model discloses going on the detailed introduction, the utility model discloses in use specific individual example right the utility model discloses an embodiment has been elucidated, the description of above embodiment is only used for helping understanding the utility model discloses, should point out, to technical personnel in this technical field, under the prerequisite that does not deviate from the principle of the utility model, can also be right the utility model discloses carry out a plurality of improvements, these improvements also fall into the protection scope of the utility model claim.

Claims

1. An endoluminal implant construct comprising a central portion having a central axis and a functional portion having an outer periphery comprised of a plurality of bars extending outwardly from the central portion, said functional portion being compressible, characterized in that:

in a non-compressed state, the functional portion includes at least first, second, and third outer peripheries formed by flanges or free ends of a plurality of rods arranged around the central axis, the first, second, and third outer peripheries being arranged in order outward from the central portion and not coplanar with each other, the first and second outer peripheries being closer to the central portion than the third outer periphery in the direction of the central axis;

the flange or free end of the rod can be pressed to move towards the central axis direction, and the second periphery and the third periphery are pressed to ensure that the implant body is positioned and held in a first posture in the cavity in which the implant body is implanted;

any one or more of the flanges or free ends forming the first outer periphery, when compressed, may cause the implant to be held in position within the cavity in which it is implanted towards the first position;

the flange faces in an outer direction of the functional portion.

2. The endoluminal implant structure of claim 1, wherein: the number of flanges or free ends constituting the first periphery is not less than the number of flanges or free ends constituting the second periphery, and at least one-to-one correspondence.

3. The endoluminal implant structure of claim 2, wherein: the flange or free end constituting the first outer periphery and the flange or free end constituting the second outer periphery corresponding thereto are substantially located in the same radial direction.

4. The endoluminal implant structure of claim 1, wherein: the first outer periphery is located between the second outer periphery and the third outer periphery in the central axis direction, or the second outer periphery is located between the first outer periphery and the third outer periphery in the central axis direction.

5. The endoluminal implant structure of claim 1, wherein: the first periphery is constituted by a flange of the rod.

6. The endoluminal implant structure according to any of claims 1-5, wherein: the third and second peripheries are both constituted by the free end, or the third periphery is constituted by the free end and the second periphery is constituted by the flange.

7. The endoluminal implant structure of claim 6, wherein: the rods comprise at least a first array of rods and a second array of rods, the third perimeter is formed by the arrangement of the free ends of the first array of rods, and the second perimeter is formed by the arrangement of the free ends or flanges of the second array of rods.

8. The endoluminal implant structure of claim 6, wherein: the third periphery is formed by arranging the free ends of the first array rods, the first array rods are further provided with branches, and the second periphery is formed by arranging the free ends or flanges of the branches of the first array rods.

9. The endoluminal implant structure according to claim 7 or 8, wherein: the first array rod is further provided with a flange formed by bending parts, included angles are formed between the front section and the rear section of each bending part of the first array rod at the bending parts, and the first periphery is formed by the flanges of the bending parts of the first array rod.

10. The endoluminal implant structure according to claim 7 or 8, wherein: the rod where the free end or the flange forming the second outer periphery is located is provided with a bent section extending in the direction away from the third outer periphery, and the tail end or the protruding end of the bent section forms the free end or the flange of the second outer periphery.

11. The endoluminal implant structure of claim 1, wherein: the second outer periphery is radially close to the first outer periphery.

12. The endoluminal implant structure of claim 1, wherein: the first, second, and third perimeters are all located on the same side of the central portion.

13. The endoluminal implant structure of claim 1, wherein: the flange or the free end has a smoothly curved surface and can be brought into contact with the inner wall of the lumen in which the implant is implanted through the smoothly curved surface.

14. The endoluminal implant structure of claim 1, wherein: the number of flanges or free ends constituting the third outer periphery is greater than the number of flanges or free ends constituting the second outer periphery.

15. The endoluminal implant structure of claim 14, wherein: the number of the flanges or free ends constituting the third outer periphery is twice the number of the flanges or free ends constituting the second outer periphery, and the flanges or free ends constituting the third outer periphery are distributed in pairs, each pair of the flanges or free ends constituting the third outer periphery and the flanges or free ends constituting the second outer periphery being distributed in a staggered manner in the circumferential direction of the central axis.

16. The endoluminal implant structure of claim 1, wherein: each rod of the functional part is made by integrally cutting a pipe and then shaping.

17. A vena cava filter having an endoluminal implant construct according to any of claims 1-16, wherein the functional portion has circumferentially uniform rods for blocking passage of thrombus through the functional portion.