CN112617917A

CN112617917A - Medical system and occluder

Info

Publication number: CN112617917A
Application number: CN202110003943.XA
Authority: CN
Inventors: 任凯炳; 朱泽荀; 李�杰; 姚瑶; 李俊菲
Original assignee: Shanghai Zuoxin Medical Technology Co Ltd
Current assignee: Shanghai Zuoxin Medical Technology Co Ltd
Priority date: 2021-01-04
Filing date: 2021-01-04
Publication date: 2021-04-09

Abstract

The invention relates to a medical system and an occluder, wherein the occluder comprises a degradable occlusion main body and a sealing element, the occlusion main body comprises an occlusion support, a near-end connecting piece and a far-end connecting piece which are connected with the two ends of the occlusion support; the sealing element is connected with the near-end connecting piece; the conveyor comprises a push rod and a balloon; the balloon is arranged at the far end of the push rod; the pushing rod is provided with a conveying channel, the far end of the conveying channel is provided with at least one outlet, and the outlet is communicated with the saccule; the balloon is arranged in the plugging bracket through the sealing piece, and applies pressure to the plugging device after filling, so that the plugging device expands from a collapsed configuration to an expanded configuration. The invention solves the problem that the degradable occluder can not expand to a preset shape and can not be fixed in the body.

Description

Medical system and occluder

Technical Field

The invention relates to the technical field of body cavity occlusion, in particular to a medical system and an occluder.

Background

Atrial fibrillation is the most common sustained arrhythmia in the clinic and is at risk of inducing ischemic stroke. The data show that more than 90% of cardiogenic thrombi are formed in the left atrial appendage in patients with non-valvular atrial fibrillation. Recent studies have shown that plugging the left atrial appendage is effective in preventing the risk of ischemic stroke due to atrial fibrillation. Since the first clinical application of plugging of the left auricle in 2001 for preventing the thromboembolic event of atrial fibrillation, the clinical application of plugging of the left auricle at home and abroad is rapidly developed, and the plugging of the left auricle becomes an important method for preventing the thromboembolic event of atrial fibrillation patients. Meanwhile, different types of left atrial appendage occlusion devices are continuously published, so that the clinical requirements are better met, and the curative effect and the safety of the operation are improved.

The occluder used for left atrial appendage occlusion in the prior art can be basically divided into two types, one type is a cage-shaped occluder represented by Watchman, and the occluder is characterized in that a self-expansion frame formed by integral cutting is provided with anchoring hooks around the self-expansion frame, the atrial surface is covered with a porous osmotic membrane, and the occluder is placed in the left atrial appendage cavity to play a role in occlusion when in use. The other type of double-disc type occluder represented by lamb is characterized by being formed by connecting a positioning disc and an occluding disc, wherein the positioning disc is embedded in the left auricle to achieve the riveting effect and also can achieve a certain occluding effect when in use, and then the occlusion disc attached to the left auricle is mainly used for achieving the occluding effect. Both current occluders share a common feature, namely being made primarily of nitinol, which once implanted in the human body will accompany the patient throughout their life. Because the materials can not be degraded, the materials can react with human tissues to inflammation, blood coagulation and the like after long-term implantation, and even can cause certain damage.

Furthermore, there may be the following risks: (1) nitinol is a non-degradable metallic material, and although its biocompatibility has been demonstrated, the long-term risk of permanent implantation is still not fully predictable and controllable; (2) the left auricle occluder permanently remains in the heart and lacks long-term follow-up data on the safety of the human body; (3) there is no clear scientific demonstration of complications such as nickel precipitation and allergy. In addition, when the left atrial appendage is completely endothelialized, the left atrial appendage occluder loses its effect and is not necessary to remain in the body. Therefore, the ideal left atrial appendage occluder should provide a temporarily-built bridge for the endothelialization of the left atrial appendage, and be degraded by the organism after the endothelialization is completed, so that the left atrial appendage occlusion is finally completed by the self tissue completely, thereby avoiding long-term complications and potential safety hazards caused by the retention of foreign matters.

Although the degradable left atrial appendage occluder is designed in the prior art, the material and the processing technology of the degradable left atrial appendage occluder are mainly researched, and a certain structural design is also provided, but the problem that the degradable material has no shape memory capacity and cannot be self-expanded to a preset shape after being pushed out of a sheath tube is still not solved.

Disclosure of Invention

In order to solve the above technical problems, an object of the present invention is to provide a medical system and an occluder, which can solve the problem that the conventional degradable occluder cannot self-expand to a predetermined shape due to the fact that the degradable material has no shape memory ability by expanding the degradable occluder with a balloon, and can also solve the problem that the conventional degradable occluder cannot be fixed to a target tissue due to insufficient mechanical properties.

In order to achieve the above object, according to a first aspect of the present invention, there is provided a medical system comprising a delivery device and an occluder;

the plugging device comprises a degradable plugging main body and a sealing element, wherein the plugging main body comprises a plugging bracket, a near-end connecting piece and a far-end connecting piece which are connected with two ends of the plugging main body; the sealing element is connected with the proximal end connecting piece;

the conveyor comprises a push rod and a balloon; the balloon is arranged at the far end of the push rod; the push rod is provided with a conveying channel, the distal end of the conveying channel is provided with at least one outlet, and the outlet is communicated with the balloon; the balloon is disposed within the occluding stent via the sealing member and is configured to apply pressure to the occluding device after filling to expand the occluding device from a collapsed configuration to an expanded configuration.

Optionally, the occlusion stent comprises an anchor.

Optionally, the blocking bracket includes a support rod, a hollow groove is disposed on the support rod, the blocking bracket includes an anchor connecting member connected to the anchor, and the anchor is wholly or partially accommodated in the hollow groove.

Optionally, the occluding stent is a braided stent or a cut stent and the anchoring elements are made of a shape memory alloy material.

Optionally, the width of the anchor is less than the width of the hollowed out groove, and/or the width of the anchor connection is greater than the width of the hollowed out groove.

Optionally, the anchoring connector is cemented, welded or lashed to the support bar.

Optionally, the sealing element is made of a shape memory alloy material and comprises a hollow tubular body, and a plurality of valve leaflets are arranged at one end opening of the body; a plurality of the leaflets are arranged along a circumference of the body.

Optionally, the body is in a shape of a circular tube, and the height of each valve leaflet is 0.55-0.75 times of the outer diameter of the body.

Optionally, a plurality of the leaflets form a taper when the seal is closed, the tapered tip being disposed outside of the body and towards a proximal end of the medical system.

Optionally, the number of the leaflets is three, and/or the length of the body is 1.0mm to 2.0 mm.

In order to achieve the above object, according to a second aspect of the present invention, there is provided an occluder comprising:

a metal stent made of a degradable material; and the number of the first and second groups,

a metal anchor made of a non-degradable material, the metal anchor being connected to the metal stent, the metal anchor automatically opening outward after the restraining force is removed;

the metallic stent is configured to expand from a collapsed configuration to an expanded configuration upon being subjected to a radial compressive force.

Optionally, the metal bracket includes a support rod, a hollow groove is formed in the support rod, the metal anchor includes an anchor connecting member connected to the metal anchor, and the metal anchor is wholly or partially accommodated in the hollow groove.

Optionally, the anchor connector is disposed inside and connected to the metal bracket.

Optionally, the width of the metal anchor is less than the width of the hollowed out groove, and/or the width of the anchor connector is greater than the width of the hollowed out groove.

Optionally, the metal bracket comprises a support rod, and a proximal end connector and a distal end connector connected to both ends of the support rod, wherein the proximal end connector comprises a sealing member configured to be opened and closed.

The whole occluder bracket in the medical system can be degraded, the problems of long-term complications and potential safety hazards caused by long-term implantation of the occluder are solved, and on the other hand, even if the degradable material of the occluder does not have shape memory capacity, the balloon in the conveyor can be used for applying expansion force to the occluder to enable the occluder to expand to a preset shape after going out of a sheath tube, so that effective occlusion of target parts (such as patent foramen ovale, atrial septal defect, ventricular septal defect, patent ductus arteriosus or other congenital heart diseases and the like) is realized, the occlusion effect is ensured, and the surgical curative effect is improved. Therefore, the invention solves the problem that the traditional degradable occluder cannot self-expand to a preset shape due to the fact that the degradable material has no shape memory capability.

When the occluder expands, the anchoring piece can automatically expand outwards after the constraint force is removed, and finally the anchoring piece penetrates into the target position to be fixed in the expansion process of the occluder, so that the stable and reliable connection between the occluder and the target position is realized, the fixation firmness of the occluder is improved, the safety of occlusion is ensured, and the life safety of a patient is ensured. Therefore, the invention also solves the problem that the traditional degradable occluder cannot be fixed with target tissues due to insufficient mechanical properties.

The sealing element is arranged at the near end of the plugging device in the medical system, so that the conveyor can be allowed to enter and exit the plugging device, and the near end of the plugging device can be sealed after the conveyor withdraws from the plugging device. Further, considering that the sealing member is small in size, almost having an outer diameter of 2 to 3mm, if such a small-sized switch is to be manufactured, high demands are placed on the manufacturing process and precision, and for this reason, the sealing member is preferably made of a shape memory alloy material, and the opening and closing of the sealing member is achieved by the closing and opening of the plurality of leaflets, so that the small-sized sealing member can satisfy the demands, the manufacturing precision can be ensured, and the structure is simple. Further, the height of the leaflet in the seal is preferably 0.55 to 0.75 times the outer diameter of the body, because the height of the leaflet in the seal is not too large, which may cause thrombus, and not too small, which may not ensure the sealing effect. The anchoring elements in the above-mentioned occluder are preferably connected to the occluding frame by means of anchoring connectors, which on the one hand increase the strength of the anchoring connection and on the other hand also increase the strength of the support rods.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the invention and do not constitute any limitation to the scope of the invention. In the drawings:

FIG. 1 is a schematic diagram of a medical system in accordance with a preferred embodiment of the present invention;

FIG. 2 is a schematic diagram of the construction of the occluding device in the preferred embodiment of the invention;

FIG. 3a is a schematic view of the seal in an open position according to the preferred embodiment of the present invention;

FIG. 3b is a schematic view of the seal in a closed position according to the preferred embodiment of the present invention;

FIG. 4 is a schematic illustration of a seal machined by laser cutting in a preferred embodiment of the present invention;

FIG. 5a-1 is a schematic diagram of the preferred embodiment of the invention after the occluder is pushed out of the sheath and before the balloon is expanded;

FIG. 5a-2 is a schematic view of the configuration of the seal shown in FIG. 5a-1 at position a 1;

FIG. 5b-1 is a schematic view of the preferred embodiment of the invention as the occluding device is being expanded;

FIG. 5b-2 is a schematic view of the configuration of the seal at position a1 in FIG. 5 b-1;

FIG. 5c is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon deflated, with the sealing member in an open position;

FIG. 5d is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon deflated, with the sealing member in an open position;

FIG. 5e-1 is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon removed;

FIG. 5e-2 is a schematic view of the configuration of the seal at position a1 in FIG. 5 e-1;

FIG. 6 is a schematic view of the anchoring element attached to the occluding stent in a preferred embodiment of the present invention;

FIG. 7 is a schematic view of an anchor assembly attached to an occluding stent in accordance with another preferred embodiment of the present invention;

FIG. 8 is a schematic diagram of the preferred embodiment of the invention after the occluder is released and before the balloon is expanded;

figure 9 is a schematic view of the preferred embodiment of the invention as it is being expanded;

FIG. 10 is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon deflated;

FIG. 11 is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon deflated and during withdrawal;

FIG. 12 is a schematic view of the preferred embodiment of the invention after the occluder has been expanded and the balloon has been removed.

The reference numerals are explained below:

100-a medical system; 10-an occluder; 11-plugging the stent; 111-a support bar; 12-a proximal connector; 13-a distal connector; 14-an anchor; 15-a seal; 151-leaflet; 152-a body; 16-an anchor connection; 17-a hollow-out groove; 18-threading holes; 19-a suture; 20-a conveyor; 21-a push rod; 22-a transport channel; 23-a balloon; 200-left atrial appendage.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to the appended drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

It should be understood that the structures, ratios, sizes, and the like shown in the drawings and described in the specification are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions under which the present invention can be implemented, so that the present invention has no technical significance, and any structural modification, ratio relationship change, or size adjustment should still fall within the scope of the present invention without affecting the efficacy and the achievable purpose of the present invention. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention. Herein, proximal refers to the end of the occluding device or medical system close to the operator, distal refers to the end of the occluding device or medical system away from the operator, and radial refers to the direction perpendicular to the axis of the occluding device or medical system.

As background technology, although the existing occluders for occluding left atrial appendage, atrial/ventricular septal defects and the like adopt biodegradable materials, the degradable materials have no shape memory capability and cannot self-expand to a preset shape after being released, so that the reliable connection between the occluders and a target position is influenced, the occluders are easy to fall off, the safety is reduced, and the target position cannot be effectively occluded, thereby influencing the curative effect of the operation. For example, most of the existing left atrial appendage occluders are made of nickel-titanium alloy materials by cutting (such as a Watchman occluder) or weaving (lamb occluder), and once implanted, the left atrial appendage occluder will be permanently retained in the heart of a human body, which brings unknown long-term risks and potential safety hazards. Although the degradable occluder can avoid the problems, the currently proposed degradable occluder does not solve the problems that the supporting force is insufficient, the left atrial appendage is not stably connected with the left atrial appendage, and the plugging cannot be effectively caused by the fact that the degradable occluder cannot restore the preset shape after being pushed out.

In order to solve the technical problem, the invention provides a novel medical system which comprises an occluder and a conveyor. The occluder can be applied to the left atrial appendage, and can also be applied to the environments of patent foramen ovale, atrial septal defect, ventricular septal defect, patent ductus arteriosus or other congenital heart diseases and the like. The plugging device is made of degradable materials, and the technical problem that the degradable materials cannot automatically expand in the prior art is solved. The invention also provides a plugging device which comprises a degradable metal stent and a metal anchor connected with the metal stent, wherein the metal anchor is non-degradable, and has shape memory capacity due to the non-degradable metal anchor, and can automatically open outwards along with the expansion of the metal stent after the constraint of the sheath is removed, so that the non-degradable metal anchor can automatically open or puncture without being pushed by the expansion of the degradable metal stent.

In the following, to illustrate the technical solution provided by the present invention, a left atrial appendage occluder is taken as an application example. The occluder provided by the invention can be degraded, the problems of long-term complications and potential safety hazards caused by long-term implantation of the occluder are avoided, the purpose of expanding the occluder to a preset shape can be achieved under the condition that the material does not have shape memory capacity, the occlusion performance of the left auricle is ensured, the stable and reliable connection between the occluder and the left auricle can be realized, the firmness of fixation of the occluder is improved, the safety of the occluder is improved, and the life safety of a patient is ensured. More specifically, the occluder of the present invention is delivered to the left atrial appendage by a delivery device and then pushed out of the sheath, after which the occluder is controllably inflated or expanded by means of a balloon to expand the occluder to a predetermined shape and, after the occluder has been expanded to a predetermined size, to push the anchoring elements on the occluder into the inner wall of the left atrial appendage. Thus, the occluding device can expand from a collapsed configuration to an expanded configuration upon application of an expansion force (i.e., radial pressure) thereto by a balloon (i.e., an external mechanism).

Next, in order to make the above objects, features and advantages of the present invention more comprehensible, preferred embodiments of the present invention are described in detail with reference to the accompanying drawings. Whilst for the purposes of explanation the following description assumes that the occluder is a left atrial appendage occluder, those skilled in the art will be able to modify the following description where appropriate with appropriate modification in detail for situations other than a left atrial appendage occluder.

Fig. 1 is a schematic structural view of a medical system in a preferred embodiment of the invention, and fig. 2 is a schematic structural view of an occluder in a preferred embodiment of the invention.

As shown in fig. 1 and 2, the present embodiment provides a medical system 100 including an occluding device 10 and a delivery device 20; the occluder 10 is used for occluding the left atrial appendage; the conveyor 20 is used to control the delivery, release, inflation, etc. of the stopper 10.

The occlusion device 10 comprises a degradable occlusion main body, the occlusion main body comprises an occlusion bracket 11, and the entire occlusion bracket 11 is made of degradable materials. The processing technology of the plugging support 11 is not limited, and the plugging support can be formed by weaving or pipe laser cutting. Preferably, the plugging support 11 is formed by cutting a degradable metal pipe, and at the moment, the plugging support 11 is a degradable metal support and has good strength and good shaping capability. The shape of the plugging frame 11 is not limited to the cage shape shown in the figure, and may be a disk shape, a dumbbell shape, a peanut shape, or the like, and the mesh shape of the plugging frame 11 is not limited to the single-layer mesh shown in the figure, or may be a multi-layer mesh. The material of the plugging support 11 can be degradable high molecular material, such as one or more of polylactic acid, polydioxanone, polycaprolactone, polyglycolide, and polyglycolide. The material of the plugging stent 11 may be degradable metal material, such as one or more of degradable magnesium alloy, zinc alloy and pure iron. Preferably, the material of the plugging stent 11 is a degradable metal material, such as a magnesium alloy which is more commonly used.

The plugging main body further comprises a proximal connecting piece 12 and a distal connecting piece 13 which are both degradable. The proximal connector 12 and the distal connector 13 are connected to the proximal end and the distal end of the occlusion stent 11, respectively. The proximal connecting element 12 may be formed separately from the plugging support 11 or may be formed integrally with the plugging support 11, and is preferably cut integrally with the plugging support 11. The distal connecting element 13 may be formed separately from the plugging frame 11 or may be formed integrally with the plugging frame 11, preferably by cutting integrally with the plugging frame 11. Preferably, the occluding stent 11 further comprises an anchor 14, and more preferably, the anchor 14 is made of a non-degradable material, and is primarily made of a non-degradable shape memory material, such as a shape memory alloy material, including but not limited to nitinol, so that the anchor 14 has a shape memory capability and is capable of automatically expanding outward when the restraining force is removed. The blocking bracket 11 has a body formed by cutting or weaving, and the anchoring element 14 and the body of the blocking bracket 11 are preferably manufactured separately, and after the separate manufacturing, the anchoring element 14 and the body of the blocking bracket 11 are connected in a non-limited manner, such as welding, binding, glue bonding, and the like. Furthermore, the anchoring elements 14 are used to penetrate the inner wall of the left atrial appendage in order to achieve a secure connection of the occluder 10 to the left atrial appendage. The shape of the anchor 14 is not required and is not limited to the illustrated linear anchor. The anchoring elements 14 extend, after expansion of the occluder 10, towards the outside of the occluder 10 in the direction of the inner wall of the left atrial appendage.

The occluder 10 further comprises a sealing member 15, wherein the sealing member 15 is connected to the proximal connector 12, and the sealing member 15 is configured to be opened and closed. In particular, the seal 15 has an open state and a closed state. When the seal 15 is in the open state, the seal 15 forms a balloon channel that allows the conveyor 20 to pass through the seal 15 so that the conveyor 20 can enter and exit the occluding stent 11; when the sealing member 15 is in the closed state, the balloon channel is sealed to seal the proximal end of the occluding device 10 and prevent blood leakage during occlusion. In a preferred embodiment, the seal 15 is in a normally closed state. Further to the dimensional constraints, the seal 15 cannot be designed to be large enough, typically only 2-3mm in size, and designing such a small seal 15 presents challenges to both structure and process. Preferably, the sealing member 15 is made of a shape memory non-degradable metal material, such as a shape memory alloy material, for example, nitinol, to make the sealing member 15 itself elastic, thereby realizing automatic opening and closing.

As shown in fig. 3a and 3b, the sealing member 15 has a shape memory capability and can be restored from the open state shown in fig. 3a to the initial closed state shown in fig. 3b after the balloon 23 and the pushing rod 21 are withdrawn from the inside of the occluding device 10. It should be understood that the seal 15 is in a normally closed state, meaning that the seal 15 is in a closed state when the medical system is manufactured, assembled, shipped, stored, or pre-operatively prepared. In the illustrated embodiment, the sealing member 15 includes a hollow tubular body 152, a plurality of valve leaflets 151 are disposed at an opening at one end of the body 152, and the valve leaflets 151 are arranged along a circumference of the body 152, generally uniformly. When the ends of the leaflets 151 remote from the body 152 are close to each other, the opening at one end of the body is closed, i.e., the balloon channel is closed, and the sealing member 15 is in a closed state; when the ends of the leaflets 151 away from the body 152 are moved away from each other, the opening at the end of the body 152 is opened, i.e., the balloon channel is opened, so that the sealing member 15 is in an open state. The structure is simple, the processing is convenient, and the requirement of the size can be met. Or other suitable structure to effect opening and closing of the seal 15, such as a small wireless valve or the like.

The present invention is not limited to the processing of the sealing member 15. In a non-limiting manufacturing method, as shown in fig. 4, the sealing member 15 is formed by laser cutting and then heat setting the degradable metal tube. Preferably, the sealing element 15 is sleeved on the proximal connecting element 12 and welded with the proximal connecting element, so that the connection strength is high and the connection is convenient. For this purpose, the inner diameter of the sealing element 15 is slightly larger than the outer diameter of the proximal connecting element 12. In another embodiment, the proximal connector 12 fits over the seal 15. In further embodiments, the proximal connector 12 itself is configured to include a seal 15. Further, 3 leaflets 151 of the same shape and size can be uniformly cut out of the degradable metal tube. Further, the body 152 is in a shape of a circular tube, the height H of each leaflet 151 is preferably (0.55-0.75) D, and D is the outer diameter of the body 152, so as to avoid the problem that the leaflet 151 will cause thrombus when being too long, and avoid the problem that the sealing is not good when the leaflet 151 is too short. The body 152 of the sealing member 15 is fitted over the proximal connector 12, and preferably, the length L of the body 152 of the sealing member 15 is 1mm to 2 mm. In addition, after the cutting is completed, the 3 leaflets 151 are folded and then heat-set in the relevant equipment at a high temperature, for example, in a salt bath furnace or an air furnace at 500-600 ℃ for 15-30 minutes. The heat-set seal 15 is then placed over the proximal connector 12 and the two welded together. Further, a plurality of the leaflets 151 taper when closed, with the tip of the taper disposed on the exterior of the body 152 and toward the proximal end of the medical system 100.

With continued reference to fig. 1, the conveyor 20 comprises a push rod 21, the push rod 21 having an axially extending conveying channel 22, the conveying channel 22 being used for conveying a medium (gas or liquid). The transporter 20 also includes a balloon 23 disposed at the distal end of the push rod 21. The far end of the delivery channel 22 is provided with at least one outlet which is communicated with the balloon 23 so as to deliver the medium into the balloon 23 through the delivery channel 22 of the push rod 21 and the outlet, so that the balloon 23 is inflated, and meanwhile, the balloon 23 can be decompressed through the outlet and the delivery channel 22. The connection mode and number of the balloon 23 on the push rod 21 are not limited in the invention. For example, a plurality of balloons 23 are attached to the push rod 21, and the plurality of balloons 23 are arranged around the axis of the push rod 21. Preferably, a balloon 23 is arranged on the push rod 21, one balloon 23 is sleeved on the push rod 21, the near end of the balloon 23 is fixedly connected with the push rod 21 in a sealing manner, and the far end of the balloon 23 is fixedly connected with the push rod 21 in a sealing manner.

In practical use, the distal end of the pushing rod 21 passes through the sealing element 15, the proximal end connecting element 12 and the plugging support 11 in sequence and then is connected with the distal end connecting element 13. The connection between the pushing rod 21 and the distal connecting member 13 is also not required, such as mechanical or non-mechanical connection, such as screw threads, clamping, and snap-fit. The pushing rod 21 serves to load the balloon 23 and also to push, adjust and expand the occluding device 10. In more detail, the balloon 23 is disposed inside the occluding stent 11 via the sealing member 15 and is used for applying pressure (i.e., an expansion force) to the occluding stent 11 after filling to expand the occluding device 10 from the collapsed configuration to the expanded configuration. The situation shown in fig. 1 is that the occluder 10 has been expanded by the balloon 23, and the balloon 23 is still inflated.

The working principle of the medical system 100 is shown in fig. 5a to 5 e. First, as shown in fig. 5a-1 and 5a-2, the distal end of the push rod 21 is connected to the distal end connector 13 through the occlusion stent 11, and the unexpanded balloon 23 is disposed in the occlusion stent 11 via the seal 15, at which time the seal 15 at the position of a1 is in an open state to allow the push rod 21 and the balloon 23 to pass through. Next, as shown in fig. 5b-1 and 5b-2, the medium is delivered to the balloon 23 through the push rod 21, so that the balloon 23 is inflated, and during the expansion of the balloon 23, the occlusion stent 11 is inflated or expanded by the expansion pressure of the balloon 23, and at this time, the sealing member 15 is still in the open state. As shown in fig. 5c, when the balloon 23 is expanded to a suitable size, the expansion is stopped, and the occluding stent 11 is expanded to a suitable size, thereby completing the expansion of the occluder 10. Thereafter, as shown in fig. 5d, the balloon 23 is deflated, and then the push rod 21 and the balloon 23 are withdrawn from the occluder 10 together, so as to obtain the occluding state shown in fig. 5e-1 and 5e-2, wherein the sealing member 15 at the position a1 is closed. In addition, the balloon 23 should be selected to be compliant and have a large diameter to allow sufficient expansion of the occluding device to a larger size.

The operating principle of the medical system 100 can also be understood as follows: after the occluder 10 is delivered to the left atrial appendage and pushed out of the sheath, the balloon 23 is inflated by the medium delivered by the push rod 21, which causes the occluder 10 to expand radially, expanding the occluder 10 to a predetermined shape and size, and during expansion of the occluder 10, the anchoring elements 14 automatically expand outward due to their shape memory and simultaneously pierce the anchoring elements 14 into the inner wall of the left atrial appendage by radial expansion of the occluder 10. Then, the pushing rod 21 is pulled lightly, and if certain resistance is felt, the plugging device 10 is firmly connected; otherwise, continuing to inject gas or liquid, continuing to fill the balloon 23 and driving the occluder 10 to further expand, and repeating the above steps until the occluder 10 is firmly connected. Thereafter, the connection between the pushing rod 21 and the occluder 10 is released, and the balloon 23 is withdrawn from the occluder 10, thereby completing the operation.

Therefore, the medical system 100 of the present invention solves the problem that the conventional degradable occluder cannot self-expand to a predetermined shape after being separated from the sheath due to no shape memory ability by means of expansion of the balloon 23, and also solves the problem that the degradable occluder cannot pierce the anchor into the inner wall of the left atrial appendage by means of radial support force. Therefore, the occluder 10 of the present invention can be degraded and supported on the left atrial appendage to complete occlusion, and overcomes the defects of the traditional non-degradable occluder and the degradable occluder. It should be appreciated that, during the process of withdrawing the balloon 23, the sealing member 15 is opened to ensure the smooth withdrawal of the balloon 23, and after the balloon 23 is withdrawn, the sealing member 15 is re-closed due to the elasticity of the material, so as to ensure the sealing performance of the occluder 10, thereby ensuring that the occluder 10 can still realize the expansion in the left atrial appendage without the shape memory capability, and can form a stable connection with the left atrial appendage without depending on the radial supporting force of the occluder. It will also be appreciated that, if a non-degradable material is chosen for the sealing member 15, there is substantially no problem of retention in the body due to its small size (about 2-3mm outer diameter).

Fig. 6 shows one way of connecting the anchoring elements 14 to the occluding stent 11 in a preferred embodiment of the present invention. As shown in fig. 6, the occlusion stent 11 further comprises an anchor connector 16, the anchor 14 is connected with the anchor connector 16, and the anchor connector 16 is connected with the body of the occlusion stent 11. Since the anchor member 14 is small, it is difficult to secure the connection strength by directly connecting it to the body of the occluding stent 11. Specifically, the occlusion stent 11 further comprises a support rod 111, the support rod 111 is provided with an anchoring connector 16, the anchoring connector 16 is usually arranged on the inner side of the occlusion stent 11, the inner anchoring connector 16 does not affect the repeated positioning and recovery of the occluding device 10, the outer anchoring connector 16 is prevented from causing unsmooth surface of the occluding device to damage tissues, and the anchoring connector 16 can also enhance the strength of the support rod 111. The width b1 of the anchor connector 16 is preferably less than or equal to the width b3 of the support bar 111 and greater than the width b2 of the anchor 14. Preferably, the width b1 of the anchor connector 16 is 0.4mm to 0.5mm, the width b2 of the anchor 14 is 0.2mm to 0.3mm, and the width b3 of the support bar 111 is 0.5mm to 0.7 mm.

With continued reference to fig. 6, the anchoring connection 16 is arranged on the inside of the blocking bracket 11 and can be connected to the support rod 111 by laser welding. Further, a hollow groove 17 is preferably formed in the support rod 111 at a position corresponding to the anchor connector 16, and after one end of the anchor 14 is connected to the anchor connector 16, the end of the anchor extends out of the blocking bracket 11 through the hollow groove 17 and extends outward. The hollow-out grooves 17 serve to facilitate the anchoring elements 14 to pass through the hollow-out grooves 17 on the supporting rods 111 and extend out of the plugging frame 11, and facilitate the anchoring elements 14 to be wholly or partially accommodated in the hollow-out grooves 17 during transportation, repeated positioning and recovery, so as to reduce the transportation size and facilitate recovery. Preferably, the hollow-out groove 17 is a long strip, the length of the hollow-out groove is consistent with the length direction of the support rod 111, and the strength of the support rod 111 cannot be reduced due to the arrangement of the hollow-out groove 17, because the anchoring connector 16 is arranged at the hollow-out groove 17 to realize the structural enhancement. Further, the width b2 of the anchor 14 is smaller than the width of the hollow slot 17, so as to facilitate the accommodation of the anchor 14 in the hollow slot 17. Further, the width b1 of the anchor connector 16 is greater than the width of the hollow-out slot 17.

Further, the length of the anchoring element 14 is preferably 1mm to 3mm, and when the occluder 10 is in an expanded configuration, the included angle α between the anchoring element 14 and the occluding stent 11 is preferably 30 ° to 40 °, which can ensure effective fixation of the occluder, and the length can prevent the anchoring element 14 from piercing the inner wall of the left atrial appendage, thereby avoiding the risk of occurrence of pericardial effusion. It will also be appreciated that if a non-degradable material is selected for the anchoring element 14, there is substantially no problem of indwelling within the body due to its small size. Optionally, the material of the anchoring connector 16 is a non-degradable metallic material, such as nitinol. Alternatively, as shown in fig. 7, the anchoring connecting piece 16 may also be bound and fixed with the blocking bracket 11, and specifically, the supporting rod 111 is provided with a threading hole 18 for binding and fixing the anchoring connecting piece 16 on the inner side of the supporting rod 111 by a suture 19. In other embodiments, the anchor connector 16 is glued to the support rod 111.

Next, the operation of the medical system 100 of the present embodiment will be described in more detail with reference to fig. 8 to 12.

Referring first to fig. 8, after the occluder 10 is delivered to the left atrial appendage 200 and pushed out of the sheath, and before expansion, the position and angle of the occluder 10 can be adjusted by the push rod 21, such as adjusting the position back and forth according to arrow a1 and adjusting the position up and down according to arrow a 2.

Referring now to FIG. 9, the operator inflates balloon 23 by inflating the lumen of push rod 21 or by injecting a fluid into the lumen, which inflates balloon 23 and causes occluder 10 to expand radially as shown by arrow A3.

With continued inflation of the balloon 23, and finally after expansion to a predetermined size, as shown in fig. 10, the inflation or filling of the balloon 23 is stopped, and the operator pulls the push rod 21 slightly to confirm whether the occluder 10 is firmly connected to the left atrial appendage 200. If the connection is secure, the push rod 21 is disconnected from the distal connector 13 and the balloon 23 is withdrawn.

Figure 11 shows the balloon 23 after decompression and when it is withdrawn from the interior of the occluding device 10. Specifically, in the direction of arrow a4, push rod 21 is pulled to withdraw balloon 23, and in the process, seal 15 is further opened to ensure balloon 23 can be withdrawn smoothly. After the balloon 23 is withdrawn from the inside of the occluding device 10, the sealing member 15 is restored to the closed state due to the elasticity, so as to ensure the sealing performance of the occluding device 10, and the whole occlusion process is completed, as shown in fig. 12.

Further, the number of the leaflets 151 of the sealing member 15 is not limited to 3, but may be 2 or more than 3, and preferably, the number of the leaflets 151 is 3, so that the structure is simple, and the sealing effect is good. Furthermore, the sealing member 15 and the proximal connecting member 12 may be formed separately or integrally. The plugging stent 11 may be provided with a coating film covering the inner surface or the outer surface of the plugging stent 11, and may cover the plugging stent 11 entirely or partially. The coating may or may not be degradable, preferably degradable. In conventional left atrial appendage occluders, the covering membrane typically covers the proximal connector such that the interior of the proximal connector is closed. The film of the present invention does not need to cover the proximal connector 12 and the sealing element 15, but only needs to close the sealing element 15 to seal off the proximal connector. After the stopper 10 is removed from the conveyor 20, the expanded shape thereof can be maintained by plastic deformation.

In conclusion, according to the technical scheme provided by the embodiment of the invention, the problem that the traditional degradable occluder cannot be self-expanded to a preset shape after being released due to the fact that the material has no shape memory capacity is solved through the balloon expansion mode, meanwhile, the anchoring on the occluder is punctured into the inner wall of the left auricle through the expansion of the balloon, the stable connection between the circumferential direction of the occluder and the left auricle is realized, the radial supporting force of the occluder is not required, and the problem of insufficient mechanical property of the degradable material is solved.

The innovations of the present invention, while originating from the field of left atrial appendage occlusion technology, it will be appreciated by those skilled in the art that the present invention is also applicable to other fields of occlusion technology, and that the source of radial pressure for the occluder of the present invention includes, but is not limited to, inflation of a balloon, and may be other suitable means.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the present invention.

Claims

1. A medical system comprising an occluder and a transporter; the plugging device comprises a degradable plugging main body and a sealing element, wherein the plugging main body comprises a plugging support, a near-end connecting piece and a far-end connecting piece which are connected to two ends of the plugging support, and the sealing element is connected with the near-end connecting piece;

2. The medical system of claim 1, wherein the occlusion stent comprises an anchor.

3. The medical system of claim 2, wherein the occlusion stent includes a support rod having a hollowed-out groove formed therein, the occlusion stent including an anchor connector coupled to the anchor, the anchor being received in the hollowed-out groove in whole or in part.

4. The medical system of claim 3, wherein the anchor linkage is adhesively, welded or lashed to the support rod.

5. The medical system of claim 3, wherein the width of the anchor is less than the width of the hollowed out groove and/or the width of the anchor connector is greater than the width of the hollowed out groove.

6. The medical system of any one of claims 2-5, wherein the occluding stent is a braided stent or a cut stent and the anchor is made of a shape memory alloy material.

7. The medical system of claim 6, wherein the seal is made of a shape memory alloy material and includes a hollow tubular body with a plurality of leaflets disposed at one end opening of the body; a plurality of the leaflets are arranged along a circumference of the body.

8. The medical system of claim 7, wherein the body is tubular and each leaflet has a height of 0.55 to 0.75 times an outer diameter of the body.

9. The medical system of claim 7, wherein a plurality of the leaflets form a taper when the seal is closed, the tapered tip being disposed outside of the body and toward a proximal end of the medical system.

10. The medical system of claim 7, wherein the number of leaflets is three, and/or the length of the body is 1.0mm to 2.0 mm.

11. An occluding device, comprising:

the metallic stent is configured to expand from a collapsed configuration to an expanded configuration upon being subjected to radial pressure.

12. The occlusion device of claim 11, wherein the metal bracket includes a support rod having a hollowed-out groove, the metal bracket including an anchor connector connected to the metal anchor, the metal anchor being wholly or partially received in the hollowed-out groove.

13. The occluder of claim 11, wherein the width of said metal anchor is less than the width of said hollowed out groove and/or the width of said anchor connector is greater than the width of said hollowed out groove.

14. The occlusion device of claim 11, wherein the anchor connector is disposed inside and connected to the metal stent.

15. The occlusion device of claim 11, wherein the metal stent comprises a support rod and proximal and distal connectors connected to both ends of the support rod, the proximal connector comprising a seal configured to open and close.