Patent Description:
Mitral regurgitation (MR) refers to that the mitral valve is not closed tightly when the heart contracts, which makes the blood reversely flow from the left ventricle to the left atrium. There are many other causes of valve regurgitation, such as valve prolapse, valve sclerosis in the elderly, rheumatic valve disease in young and middle-aged people, infective inflammation of valve, cardiac enlargement and so on. This causes to prevent the left ventricle from filling during diastole.

According to the severity, the manifestations of mitral regurgitation vary greatly. Mild mitral regurgitation cannot appear clinical symptoms for a long time and has a good prognosis; severe mitral regurgitation can lead to pulmonary hypertension, atrial fibrillation, heart failure, shock and death. According to severity of the disease, mitral regurgitation can be divided into acute and chronic MR. Patients with acute severe mitral regurgitation have poor tolerance, which may cause severe pulmonary edema and shock, and have poor prognosis. For chronic severe MR, patients will appear symptoms within <NUM>-<NUM> years. The incidence rate of all-cause death, cardiac death and cardiovascular events for asymptomatic ones within <NUM> years are <NUM> ± <NUM>%, <NUM> ± <NUM>% and <NUM> ± <NUM>%, respectively. And the mortality rate of patients with severe heart failure is <NUM>% per year. A number of studies have shown that mitral regurgitation is a powerful and independent predictor of prognosis in patients with heart failure, and the mortality rate of patients with moderate or severe mitral regurgitation is significantly higher than that of patients without or with mild mitral regurgitation.

There are about <NUM> million patients with mitral regurgitation currently in China. At present, the standard mitral valve operation in China is open sternotomy, which uses cardiopulmonary bypass to stop the heart and implants mechanical or biological prosthetic valve, wherein the artificial biological valve is a central blood flow type, which is close to the normal function of the prosthetic valve, has good hemodynamic performance, little damage to the blood components, low incidence of thromboembolism, and no need for lifelong anticoagulation after operation, and thus avoid bleeding complications caused by over dosage of anticoagulants. Although the biological prosthetic valve replacement technology is relatively mature, long-term durability has been clinically proven, but the operation is very difficult and the trauma is large. Most of patients are in a dilemma that they cannot be cured by taking medicines, while there is a high risk in the thoracotomy operation of mitral valve repair.

Recently, a transcatheter technique has been developed to introduce and implant artificial heart valves by utilizing soft catheters in a much less invasive manner than open heart surgery. In this technique, the prosthetic valve is installed on the end part of the soft catheter in a curled state and advances through the patient's blood vessels until the valve reaches the implanted position. The valve at the end of the catheter is then located at the defective native valve, and a valve stent is anchored at the native valve through balloon dilation or self-expansion.

Another known technique for implanting an artificial aortic valve is a transapical approach, which creates a small incision in chest wall of the patient, and the catheter moves through the apex (i.e., the bottom end) until the valve reaches the implanted position.

The unique anatomical structure of the mitral valve presents a great challenge to the transcatheter mitral valve replacement device. Firstly, the contour shape of mitral valve annulus is not symmetrical and uniform, but non-circular D shape or kidney like shape. This unpredictability makes it difficult to design a mitral valve replacement device that fits the contour shape of the mitral valve annulus completely. If the mitral valve replacement device and the native valve leaf and/or the valve annulus cannot fully fit, it may leave gaps in them, which will cause the blood to flow back to the left atrium through these gaps, forming a perivalvular leakage.

Secondly, the mitral valve annulus lacks radial support from surrounding tissue. Unlike the aortic valve, which is completely surrounded by fibrous elastic tissue, the mitral valve annulus can support and fix the prosthetic valve by providing its native structure characteristics; the mitral valve is bound to the outer wall only by muscle tissue. The inner wall of the mitral valve is bound by a thin vascular wall, which separates the mitral valve annulus from the internal part of the aortic outflow tract. Therefore, if a relatively large radial support force is applied to the mitral valve annulus, such as the support force provided by the dilated stent, it may lead to collapse of the internal part of the aortic outflow tract, with potentially fatal consequences.

The patent application <CIT> discloses prosthetic heart valve device for percutaneous replacement of a native heart valve.

The patent <CIT> discloses a prosthetic mitral valve with a frame.

The patent application <CIT> discloses prosthetic heart valve devices and associated methods for percutaneous heart valve replacement.

In view of the difficulties associated with current methods, there is still a need for devices and methods that can be firmly positioned, effective and less invasive for the treatment of dysfunctional heart valves.

Based on the above purposes, the present invention provides a transapical implantable mitral valve device, which includes: an outer valve stent comprising an outer valve stent body that is composed of a plurality of first structure units arranged in a circumferential direction, and an anchoring unit that is disposed on the outer valve stent body for anchoring the mitral valve device within a human body; an inner surface and/or an outer surface of the outer valve stent body being covered with outer skirt; an inner valve stent disposed inside the outer valve stent and interconnected with the outer valve stent, a cavity being formed between the outer valve stent and the inner valve stent; and a valve leaflet structure disposed inside the inner valve stent to form a prosthetic valve.

In a specific embodiment, the inner valve stent includes an inner valve stent body composed of a plurality of second structure units arranged in the circumferential and axial directions.

In a specific embodiment, an inner surface and/or an outer surface of the inner valve stent are covered with inner skirt.

In an alternative embodiment, materials of the outer valve stent and the inner valve stent are selected from hyperelastic alloy and shape memory alloy materials.

In a specific embodiment, tail ends of a plurality of the second structure units at the left ventricular end of the mitral valve device extend and turn out to form a first connecting structure that is connected with the first structure units of the outer valve stent body so as to connect the outer valve stent with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent; optionally, an angle of turning out is <NUM> degrees to <NUM> degrees.

In a specific embodiment, the left ventricular end of the first structure units turns in to form a second connecting structure that is connected with the second structure units of the inner valve stent body so as to connect the outer valve stent with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent; optionally, an angle of turning in is <NUM> degrees to <NUM> degrees.

In a specific embodiment, tail ends of a plurality of the second structure units at the left ventricular end of the mitral valve device extend and turn out to form a first connecting structure, the left ventricular end of the first structure units turns in to form a second connecting structure that is connected with the first connecting structure so as to connect the outer valve stent with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent; optionally, both an angle of turning out and an angle of turning in are <NUM> degrees to <NUM> degrees.

In an alternative embodiment, an inside or outside of the first connecting structure and/or an inside or outside of the second connecting structure is provided with joint skirt.

In a specific embodiment, the first structure units are provided with a plurality of sets of holes, the left ventricular end of the second structure units, the structure unit joint of the second structure units and/or the left atrial end of the second structure units are provided with filamentous connecting structures, each filamentous connecting structure penetrates into each hole of a set of the holes and is fixed, so as to connect the outer valve stent with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent; optionally, an angle formed between the filamentous connecting structures and the axial direction of the mitral valve device is <NUM> degrees to <NUM> degrees.

In an alternative embodiment, the number of holes for each set of the holes is <NUM>-<NUM>.

In a preferred embodiment, in case that the left ventricular end of the second structure units is provided with filamentous connecting structures, and the structure unit joint or the left atrial end of the second structure units is provided with filamentous connecting structures, the number of filamentous connecting structures at the structure unit joint or the left atrial end is less than the number of filamentous connecting structures at the left ventricular end.

In an alternative embodiment, the number of filamentous connecting structures at the left ventricular end is <NUM>-<NUM>; the number of filamentous connecting structures at the structure unit joint or at the left atrial end is <NUM>-<NUM>.

In a specific embodiment, the inner valve stent is an improved surgical biological prosthetic valve, which includes a frame, a valve leaflet structure arranged inside the frame, and an annular sealing ring arranged at the left atrial end of the frame, wherein the frame and the annular sealing ring are compressible.

In a specific embodiment, the improved surgical biological prosthetic valve after compression in the radial direction has a radius of less than <NUM>, so that the mitral valve device is loaded into the sheath.

In a specific embodiment, a plurality of filamentous connecting structures are arranged at periphery of the annular sealing ring, and a plurality of sets of holes are arranged on the outer valve stent, each filamentous connecting structure passes through a set of said holes and is fixed, so that the outer valve stent is connected with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent; optionally, the acute angle formed by the filamentous connecting structures and the axial direction of the mitral valve device is <NUM> degrees to <NUM> degrees.

In a specific embodiment, a clip structure is provided at the end of the first structure units of the outer valve stent near the left atrial, which is used to hold the annular sealing ring, so that the outer valve stent is connected with the inner valve stent, and a cavity is formed between the outer valve stent and the inner valve stent.

The anchoring unit includes a U-shaped structure unit and an S-shaped structure unit, wherein the U-shaped structure unit is provided at the left atrial end of the outer valve stent body to locate the mitral valve device at the mitral valve annulus, and the S-shaped structure unit is provided at the left ventricular end of the outer valve stent body to fix with the mitral valve leaflet.

In a specific embodiment, terminal of the left atrial end of the U-shaped structure unit and terminal of the left ventricular end of the S-shaped structure unit are provided with pull rings; optionally, the shape of the pull rings is circular, rounded rectangle, preferably rounded rectangle.

In a specific embodiment, a vertical distance between the horizontal plane on which endpoint of the S-shaped structure unit near the left atrial end locates and the horizontal plane on which endpoint of the U-shaped structure unit near the left ventricular end locates is <NUM> to <NUM>.

In a specific embodiment, the S-shaped structure unit has a thickness on the radial direction of <NUM> to <NUM>.

In a specific embodiment, a plurality of the U-shaped structure units constitute a circular structure which has a large circle diameter of <NUM> to <NUM>.

In a specific embodiment, the first structure unit and/or the second structure unit are provided to be <NUM>-<NUM>.

In a specific embodiment, the cavity formed between the outer valve stent and the inner valve stent has a thickness in the radial direction of not less than <NUM>.

In a specific embodiment, the outer skirt, the inner skirt and/or the joint skirt are arranged to seal the mitral valve device, leaving an opening only at the valve leaflet structure to pass through blood.

In an alternative embodiment, material of the valve leaflet structure is animal pericardium or polymer material, preferably, material of the valve leaflet structure is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane; material of the outer skirt is animal pericardium or polymer material, preferably, material of the outer skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane; material of the inner skirt is animal pericardium or polymer material, preferably, material of the inner skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane; material of the joint skirt is animal pericardium or polymer material, preferably, material of the joint skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane.

It can be seen that the transapical delivery mitral valve device provided by the present invention is used to implant into the in-situ mitral valve with lesions caused by mitral valve stenosis or mitral valve regurgitation/insufficiency, which has the following advantages:.

Hereinafter, the present invention will be further described in combination with the accompanying drawings.

It should be understood that the appended drawings are not drawn to scale, but merely to illustrate a properly simplified representation of various features of the basic principles of the present invention. The specific design features of the present invention disclosed herein including, for example, specific dimensions, directions, positions and shapes will be determined in part by the specific application and use environment.

The present invention concept of the present invention includes a plurality of specific embodiments, different embodiments have different technical or application emphases, different embodiments can be combined and matched to meet different application scenarios and solve different application requirements. Therefore, the following description of specific embodiments shall not be understood as a limitation of the technical solutions intended to be protected by the present invention.

<FIG> is a partial structure schematic view of the transapical implantable mitral valve device provided in the first embodiment of the present invention. As shown in <FIG>, in this embodiment, the transapical implantable mitral valve device includes an outer valve stent <NUM>, an inner valve stent <NUM> and a valve leaflet structure <NUM>, and an outer skirt <NUM> covering an inner surface and/or an outer surface of the outer valve stent <NUM> and an inner skirt <NUM> covering an inner surface and/or an outer surface of the inner valve stent <NUM>.

<FIG> is a structure schematic view of the transapical implantable mitral valve device provided in the first embodiment of the present invention implanted into the human body. <FIG> is a structure schematic view of the outer valve stent of the transapical implantable mitral valve device provided by the first embodiment of the present invention. As shown in <FIG>, the special contour shape of the outer valve stent <NUM> can be firmly anchored to the human mitral valve annulus. Moreover, the outer valve stent <NUM> provides radial support force for the mitral valve annulus, and can grasp the diseased mitral valve leaflet of human body and fix it on the mitral valve annulus. Specifically, in this embodiment, the outer valve stent <NUM> includes an outer valve stent body of an annular network structure that is composed of a plurality of first structure units <NUM> arranged in a circumferential direction, which provides radial support force for the mitral valve annulus, so that the valve device can be positioned in the mitral valve annulus. In the present embodiment, the first structure units <NUM> may be a diamond shape defined by stent rods; it also can be a square, circular, rectangular or other shape, but the diamond shape is preferable. These shapes allow the valve stent to be stretched axially while being compressed radially for easy delivery into the body. The outer valve stent <NUM> also includes an anchoring unit for anchoring the mitral valve device, which anchors the mitral valve device at the mitral valve annulus in combination with the radial support force of the outer valve stent body.

As shown in <FIG> the anchoring unit includes a U-shaped structure unit <NUM> and an S-shaped structure unit <NUM>. The U-shaped structure unit <NUM> and the S-shaped structure unit <NUM> can grasp the diseased mitral valve leaflet of human body and fix it on the mitral valve annulus. The mitral valve device is implanted into the patient, the U-shaped structure unit <NUM> is close to the left atrial end of the patient, and the S-shaped structure unit <NUM> is close to the left ventricular end of the patient. Therefore, in this specification, when the mitral valve device is implanted into the patient, the end of the U-shaped structure unit of the mitral valve device is also called the left atrial end (or head end) of the mitral valve device, and the end of the S-shaped structure unit of the mitral valve device is also called the left ventricular end (or tail end) of the mitral valve device. In addition, in this specification, it is defined that after the mitral valve device is implanted into the patient, the surface of the mitral valve device that contacts the heart tissue is the outer surface (or exterior, outside surface, outside) of the mitral valve device; corresponding to the outer surface, the surface of the mitral valve device providing the prosthetic valve leaflet structure is the inner surface (or interior, inside surface, inside) of the mitral valve device. In addition, as shown in <FIG>, it is defined in the specification that the direction from the left atrial end (or head end) to the left ventricular end (or tail end) of the mitral valve device in <FIG> is vertical direction (or axial direction), and the corresponding direction perpendicular to the vertical direction is horizontal direction (or radial direction).

As shown in <FIG>, in this embodiment, the number of the first structure units <NUM> is between <NUM> and <NUM>. Preferably, the number of the first structure units <NUM> is between <NUM> and <NUM>. The left atrial end of each first structure unit <NUM> is connected with one U-shaped structure unit <NUM> whose opening is toward the interior of the mitral valve device. Therefore, the U-shaped structure unit <NUM> is also arranged in the circumferential direction to form a ring. As shown in <FIG>, the annularly arranged U-shaped structure unit <NUM> can be positioned at the left atrial end of the human mitral valve annulus, so that the mitral valve device cannot move to the left ventricular end, thus further fixing the position of the mitral valve device. In this embodiment, the S-shaped structure unit <NUM> is formed by bending the left ventricular end of each first structure unit <NUM> outwards to form an S-shaped structure. As shown in <FIG>, the S-shaped structure unit <NUM> can grasp the diseased mitral valve leaflet of human body and further fix the mitral valve device on the mitral valve annulus.

As shown in <FIG>, in this embodiment, both a terminal of the U-shaped structure unit <NUM> near the left atrial end and a terminal of the S-shaped structure unit <NUM> near the left ventricular end are provided with pull rings <NUM>. Alternatively, the shape of the pull rings <NUM> may be a circle, a rounded rectangle, etc., preferably a rounded rectangle. The pull rings <NUM> can fix the mitral valve device on a delivery system, which is convenient for transferring the mitral valve device into the human body.

<FIG> is a top schematic view of the outer valve stent of the transapical implantable mitral valve device provided by the first embodiment of the present invention. As shown in <FIG>, the largest circumscribed circle A (i.e. the large circle of the ring) of the plurality of U-shaped structure units <NUM> which form the ring has a diameter between <NUM> and <NUM>, and the diameter range can make the mitral valve device unable to move from the left atrial end to the left ventricle through the mitral semi-annulus. At the same time, in this embodiment, when using the mitral valve device, the depth of the whole mitral valve device invading the left atrium is less than <NUM>; the depth of the whole mitral valve device invading the left ventricle is less than <NUM>. Preferably, the depth of the invasion into the left atrium ranges between <NUM> and <NUM>, and the depth of the invasion into the left ventricle ranges between <NUM> and <NUM>. The invasion depth of the above-mentioned mitral valve device is determined by the overall length of the outer valve stent in the axial direction. Therefore, the overall length ranges between <NUM> and <NUM>, and said appropriate length can make the mitral valve device placed in the valve leaflet and avoid touching the tissue in the ventricle.

As shown in <FIG>, the vertical distance B between the horizontal plane on which the endpoint of the S-shaped structure unit <NUM> near the left atrial end locates and the horizontal plane on which the endpoint of the U-shaped structure unit <NUM> near the left ventricular end locates is between <NUM> and <NUM>, preferably between <NUM> and <NUM>. The above-mentioned gap between the U-shaped structure unit and the S-shaped structure unit forms a shape of a C-shaped clip. When in use, the gap is clamped at the valve annulus to fix the mitral valve device.

The S-shaped structure unit <NUM> shall be as close as possible to the body composed of the first structure units <NUM> in the horizontal direction, that is, the thickness of the S-shaped structure unit <NUM> in the radial direction shall be as small as possible. Specifically, the thickness of the S-shaped structure unit <NUM> in the radial direction is <NUM> to <NUM>, which can ensure that the mitral valve device does not touch the tissue in the ventricle.

<FIG> is a structure schematic view of the inner valve stent of the transapical implantable mitral valve device provided by the first embodiment of the present invention. As shown in <FIG>, in this embodiment, the inner valve stent <NUM> is an interventional mitral valve stent. Specifically, the inner valve stent <NUM> includes a plurality of second structure units <NUM> which are arranged along the circumferential and axial directions to form an inner valve stent body of a circular network structure. In the present embodiment, the second structure unit <NUM> may be a diamond shape defined by stent rods; it also can be a square, circular, rectangular or other shape, but a diamond shape is preferable. These shapes allow the valve stent to be stretched axially while being compressed radially for easy delivery into the body. The tail ends of the plurality of second structure units <NUM> close to the left ventricular end extend and turn out to form first connecting structures <NUM>. The diameter of circumscribed circle of the plural first connecting structures <NUM> formed through turning out is consistent with the inner diameter of the outer valve stent body, so that when the inner valve stent <NUM> is placed inside the outer valve stent <NUM>, the plurality of first connecting structures <NUM> can be in contact with the inner wall of the outer valve stent body, which further facilitates fixation of the two. The inner valve stent <NUM> and the outer valve stent <NUM> are rigidly connected by the first connecting structures <NUM>. Because the first connecting structures <NUM> are formed by turning out the second structure units <NUM>, there is a certain distance between the inner wall of the outer valve stent and the outer wall of the inner valve stent, and a cavity is formed, which cavity can prevent impact on the inner valve stent when the outer valve stent is deformed. Preferably, the number of the second structure units <NUM> arranged in the circumferential direction is the same as the number of the first structure units <NUM>.

Specifically, as shown in <FIG>, in the radial direction, there is a certain distance between the outer valve stent <NUM> and the inner valve stent <NUM>, forming a cavity <NUM>. The outer valve stent <NUM> will be deformed by compression of the irregular mitral valve annulus in the human body, while the cavity <NUM> can provide a buffer space to keep the shape of the valve leaflet structure <NUM> always unchanged. In this embodiment, in the radial direction, there is a certain distance between the outer valve stent <NUM> and the inner valve stent <NUM> which is not less than <NUM>, that is, the thickness of the cavity formed between the outer valve stent <NUM> and the inner valve stent <NUM> in the radial direction is not less than <NUM>. Preferably, the thickness of the cavity in the radial direction is <NUM> to <NUM>.

Alternatively, as shown in <FIG>, in this embodiment, the first connecting structure <NUM> is a triangular structure or other shaped structure formed by turning out the left ventricular end of the second structure units <NUM>. The number of the first connecting structures <NUM> is between <NUM> and <NUM>, preferably <NUM> or <NUM>, that is, the number of the second structure units <NUM> arranged in the circumferential direction.

Further, as shown in <FIG>, in this embodiment, a layer of outer skirt <NUM> is wrapped on the inner surface and/or outer surface of the outer valve stent <NUM>, and the outer skirt <NUM> is laid flat around the surface of the outer valve stent <NUM> to cover a circle and covers the first connecting structure <NUM> of the inner valve stent <NUM> at the same time, and is fixed by means of suturing, pressing or bonding, etc. The inner surface and/or outer surface of the inner valve stent <NUM> is wrapped with a layer of inner skirt <NUM>, which is laid flat around the surface of the inner valve stent <NUM> to cover a circle, and is fixed by means of suturing, pressing or bonding, etc. The valve leaflet structure <NUM> is fixed on the inner skirt <NUM> by suturing to replace the in-situ mitral valve diseased in human body. The inner valve stent <NUM> and the outer valve stent <NUM> are rigidly connected by the first connecting structures <NUM>, and at the same time, they are flexibly connected by the outer skirt <NUM>. Therefore, the outer skirt <NUM> and the inner skirt <NUM> are arranged so that the blood flowing from the left atrium to the left ventricle can only pass through the valve leaflet structure <NUM> of the inner valve stent <NUM> when passing through the mitral valve device, but not through the other parts of the mitral valve device, that is to avoid peripheral leakage.

In this embodiment, material of the valve leaflet structure is animal pericardium or polymer material. Preferably, material of the valve leaflet structure is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane. In this embodiment, material of the outer skirt is animal pericardium or polymer material. Preferably, material of the outer skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane.

In this embodiment, material of the inner skirt is animal pericardium or polymer material. Preferably, material of the inner skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane.

<FIG> is a three-dimensional structure schematic view of an assembly manner for the outer valve stent and the inner valve stent of the transapical implantable mitral valve device provided by the first embodiment of the present invention; <FIG> is a top schematic view of the assembly manner of <FIG>. <FIG> is a partial schematic view of connecting portion of a kind of rigid connection of the assembly manner of <FIG>. As shown in <FIG>, <FIG> and <FIG>, the first connecting structure <NUM> formed by turning out the inner valve stent <NUM> includes two first straight rods <NUM> which intersect to form a first vertex <NUM>. Accordingly, there is a structure unit joint <NUM> between the adjacent first structure units <NUM> of the outer valve stent <NUM>. After the inner valve stent <NUM> is placed into the inner valve stent, the first vertex <NUM> corresponds to and contacts with the structure unit joint <NUM>, and the two are fixed by means of suturing, pressing or bonding, etc., so that the inner valve stent <NUM> is connected with the outer valve stent <NUM> (as shown in <FIG>).

<FIG> is a partial schematic view of a connecting portion of another kind of rigid connection of the assembly manner of <FIG>. As shown in <FIG>, there is a structure unit joint between the adjacent first structure units <NUM> of outer valve stent <NUM>, and the left ventricular end of the structure unit joint includes respective second straight rods <NUM> of two adjacent first structure units <NUM>. As shown in <FIG>, in this embodiment, one of the second straight rods <NUM> is aligned with one of the first straight rods <NUM>, and the first straight rod <NUM> and the second straight rod <NUM> are fixed by means of suturing, pressing or bonding, etc., so that the inner valve stent <NUM> is connected with the outer valve stent <NUM>. The rigid connection described above is achieved by contacting the stent rod of the outer valve stent with the stent rod of the inner valve stent; therefore, the combination manner between the second straight rod <NUM> and the first straight rod <NUM> is not limited to the above exemplary ways.

Alternatively, the above first straight rod <NUM> may be in a straight line shape, and the first straight rod <NUM> may also be in an arc shape.

Alternatively, in the present embodiment, as previously described, the outer skirt <NUM> is laid flat around the surface of the outer valve stent <NUM> to cover a circle, and covers the first connecting structure <NUM> of the inner stent <NUM> at the same time, which is used as a flexible connection. In addition, on such basis, joint skirt is sutured on the inside or outside of the first connecting structure <NUM> simultaneously, which is further used as a flexible connection to play a reinforcing role. In other embodiments, the joint skirt may also not be added. The skirt of the flexible connection can play the role of strengthening and blocking the blood. Like the outer skirt and inner skirt, material of the joint skirt is animal pericardium or polymer material. Preferably, material of the joint skirt is bovine pericardium, pig pericardium, polytetrafluoroethylene, fiber cloth or fiber membrane.

In this embodiment, the outer valve stent <NUM> and the inner valve stent <NUM> are integrally made of hyperelastic alloy and/or shape memory alloy materials, in particular, formed by laser cutting pipes of such materials.

In order to ensure that the inner valve stent will not be compressed to deform by the diseased mitral valve annulus, the inner valve stent has a certain degree of freedom, that is, the position of the inner stent in the outer stent is not stationary, because the cavity between the inner valve stent and the outer valve stent can be deformed by force, so the contour of the inner valve stent is not affected and its function is guaranteed. The first connecting structure <NUM> of a triangular shape or other shape formed by turning out the second structure units has an out-turning angle C of between <NUM> degrees and <NUM> degrees (see <FIG>). The out-turning angle refers to the angle formed by the line connecting the terminal of the first connecting structure <NUM> with the place where it turns out and bends with respect to the vertical direction, see <FIG>. As mentioned previously, in the radial direction, there is a certain distance between the outer valve stent <NUM> and the inner valve stent <NUM> (that is, to form a cavity), which can buffer the impact on the inner stent due tocompression deformation of the outer stent.

<FIG> is a top schematic view of the outer valve stent of the transapical implantable mitral valve device provided by the second embodiment of the present invention; and <FIG> is a structure schematic view of the outer valve stent of the transapical implantable mitral valve device provided by the second embodiment of the present invention. As shown in <FIG>, in this embodiment, the outer valve stent <NUM> provides radial support force for the mitral valve annulus, and can grasp the diseased mitral valve leaflet of human body and fix it on the mitral valve annulus. Specifically, the outer valve stent <NUM> includes a body of annular network structure that is composed of a plurality of first structure units <NUM> arranged in the circumferential direction to provide radial support force for the mitral valve annulus, and a U-shaped structure unit <NUM> and an S-shaped structure unit <NUM> which play an anchoring effect on the mitral valve device. The U-shaped structure unit <NUM> and the S-shaped structure unit <NUM> can grasp the diseased mitral valve leaflet of human body and fix it on the mitral valve annulus.

In the present embodiment, the number of the first structure units <NUM> ranges between <NUM> and <NUM>. Preferably, the number of the first structure units <NUM> is between <NUM> and <NUM>. In the present embodiment, two adjacent first structure units <NUM> form a structure unit joint, and two adjacent structure unit joints are connected with a U-shaped structure unit <NUM> along the left atrial end, whose opening is toward the inside of the mitral valve device, and is connected with the S-shaped structure unit <NUM> along the left ventricular end. The U-shaped structure unit <NUM> and the S-shaped structure unit <NUM> can grasp the diseased mitral valve leaflet of human body and fix it on the mitral valve annulus.

As shown in <FIG>, in the present embodiment, the end of the first structure unit <NUM> of the outer valve stent <NUM> close to the left ventricle folds toward the interior of the mitral valve device, forming an in-turning triangular second connecting structure <NUM>. The diameter of the inscribed circle of the plurality of second connecting structures <NUM> formed through turning in is consistent with the outer diameter of the inner valve stent body, so that the plurality of second connecting structures <NUM> can be in contact with the outer wall of the inner valve stent body.

<FIG> is a structure schematic view of the inner valve stent of the transapical implantable mitral valve device provided by the second embodiment of the present invention. As shown in <FIG>, the inner valve stent <NUM> in this embodiment has a structure basically similar to that of the inner valve stent in Embodiment <NUM>, but the end of the second structure unit close to the left ventricle in this embodiment does not turn out.

<FIG> is a three-dimensional structure schematic view of the assembly manner for the outer valve stent and the inner valve stent of the transapical implantable mitral valve device provided by the second embodiment of the present invention; and <FIG> is a top schematic view of the assembly manner of <FIG>. As shown in <FIG>, <FIG> and <FIG>, the tip <NUM> of the inner valve stent <NUM> close to the left ventricular end is aligned with the second vertex <NUM> of the in-turning triangular second connecting structure <NUM> of the outer valve stent 201close to the left ventricular end, and the tip <NUM> and the second vertex <NUM> are fixed by suturing, pressing or bonding, etc., so as to make the outer valve stent <NUM> and the inner valve stent <NUM> interconnected. In this embodiment, the second vertex <NUM> is formed by intersection of two sides (two third straight rods <NUM>) of the same first structure unit <NUM> close to the left ventricular end (i.e., an angle of the diamond).

As in Embodiment <NUM>, in this embodiment, a layer of outer skirt is wrapped on the inner surface and/or outer surface of the outer valve stent <NUM>, the inner surface and/or outer surface of the inner valve stent <NUM> is wrapped with a layer of inner skirt, and the inner skirt and/or outer skirt can be covered to the second connecting structure <NUM> as a flexible connection. Alternatively, joint skirt can also be provided at the second connecting structure <NUM>.

In this embodiment, the number of the second connecting structures <NUM> ranges between <NUM> and <NUM>, preferably <NUM> or <NUM>. In order to ensure that the inner stent will not be compressed to deform by the diseased mitral valve annulus, the inner valve stent has a certain degree of freedom, and the in-turning second connecting structure <NUM> of a triangle or other shapes of the first structure unit has an in-turning angle D between <NUM> degrees and <NUM> degrees. The in-turning angle refers to an angle formed by a line connecting the terminal of the second connecting structure <NUM> with the place where it turns in and bends with respect to the vertical direction (see <FIG>). There is a certain distance between the outer valve stent <NUM> and the inner valve stent <NUM> (i.e. forming a cavity), which can buffer the impact on the inner stent due to compression deformation of the outer stent.

Other things not specifically described in this embodiment are the same as those in Embodiment <NUM>, such as materials of various parts of the mitral valve device.

In the present embodiment, the inner valve stent of the transapical implantable mitral valve device is the same as that in Embodiment <NUM>, and the outer valve stent is the same as that in Embodiment <NUM>. <FIG> show a plurality of rigid connection combinations optional for the inner valve stent and the outer valve stent of the mitral valve device in the third embodiment of the present invention. As shown in <FIG>, the in-turning triangular second connecting structure <NUM> of the outer valve stent is overlapped with the out-turning triangular first connecting structure <NUM> of the inner valve stent; the third straight rod <NUM> of the outer valve stent intersects with the first straight rod <NUM> of the inner valve stent, enclosing to form a diamond shape, and the second vertex <NUM> of the in-turning triangular second connecting structure <NUM> of the outer valve stent and the first vertex <NUM> of the out-turning triangular first connecting structure <NUM> of the inner valve stent are located on a diagonal line of the diamond shape, and are fixed by suturing, pressing or bonding, etc..

Alternatively, as shown in <FIG>, a third straight rod <NUM> of the in-turning triangular second connecting structure <NUM> of the outer valve stent coincides with a first straight rod <NUM> of the out-turning triangular first connecting structure <NUM> of the inner valve stent <NUM>, and they are fixed by suturing, pressing or bonding, etc..

Alternatively, as shown in <FIG>, the in-turning triangular second connecting structure <NUM> of the outer valve stent and the out-turning triangular first connecting structure <NUM> of the inner valve stent completely coincide, that is, the two first straight rods and the first vertex correspondingly coincide with the two third straight rods and the second vertex, and they are fixed by suturing, pressing or bonding, etc..

The first connecting structure <NUM> and the second connecting structure <NUM> have the same number which is between <NUM> and <NUM>, preferably <NUM> or <NUM>. In order to ensure that the inner stent will not be compressed to deform by the diseased mitral valve annulus, the inner stent has a certain degree of freedom. Both the in-turning angle E of the in-turning second connecting structure <NUM> of a triangle or other shape and the in-turning angle F of the out-turning first connecting structure <NUM> of a triangle or other shape are between <NUM> degrees and <NUM> degrees (see <FIG>). There is a certain distance between the outer valve stent and the inner valve stent (i.e. forming a cavity), which can buffer the impact on the inner stent due to compression deformation of the outer stent.

Other aspects not specifically described in this embodiment are the same as those in Embodiment <NUM>, such as material of each part of the mitral valve device and provision of skirts, etc. In addition, in this embodiment, the joint skirt can be arranged on the outside or inside of the first connecting structure <NUM>, or on the outside or inside of the second connecting structure <NUM>, or the joint skirts are arranged on both the first connecting structure <NUM> and the second connecting structure <NUM>, and the joint skirt can also be arranged between the first connecting structure <NUM> and the second connecting structure <NUM>.

<FIG> is a structure schematic view of a rigid connection of the assembly manner optional for the outer valve stent and the inner valve stent of the transapical implantable mitral valve device provided by the fourth embodiment of the present invention. As shown in <FIG>, the inner valve stent <NUM> includes a plurality of second structure units <NUM>, which are arranged in the circumferential and axial directions to form an inner valve stent body of annular network structure. In the present embodiment, a filamentous connecting structure <NUM> is also provided on the end of the plurality of or each second structure unit <NUM> near the left ventricular.

In the present embodiment, the contour shape of the outer valve stent <NUM> is basically consistent with the structure of the outer valve stent of Embodiment <NUM> or Embodiment <NUM>; however, in the present embodiment, the outer valve stent <NUM> is also provided with sets of holes. As shown in <FIG>, the holes <NUM> are distributed at the structure unit joint <NUM> of the first structure unit <NUM> adjacent to the outer valve stent <NUM> or at the second straight rod <NUM>, meanwhile, a groove structure <NUM> is provided around the holes <NUM> to prevent the suture from displacement and falling off. Alternatively, the opening shape of the hole <NUM> may be a circle, a rounded rectangle, etc..

In this embodiment, the filamentous connecting structure <NUM> passes through each hole of a set of holes <NUM> on the outer valve stent <NUM> successively from an end near the left atrium to an end near the left ventricle (<FIG>) or from an end near the left ventricle to an end near the left atrium (<FIG>), and the hole <NUM> is fixed with the filamentous connecting structure <NUM> passing through the hole with the suture <NUM>, so that the outer valve stent <NUM> and the inner valve stent <NUM> are fixed (as shown in <FIG>). The number of holes in each set of holes <NUM> ranges between <NUM> and <NUM>, preferably <NUM>. In this embodiment, the number of the sets of holes <NUM> is the same as the number of the filamentous connecting structures <NUM>, and the number of the filamentous connecting structures <NUM> ranges between <NUM> and <NUM>, preferably <NUM> or <NUM>, which are evenly distributed in the circumferential direction of the inner valve stent <NUM>. The angle G of the lateral wall of the outer valve stent <NUM> formed by the filament connecting structure <NUM> and the structure unit <NUM> of the outer valve stent <NUM> is between <NUM> degrees and <NUM> degrees. There is a certain distance between the outer valve stent <NUM> and the inner valve stent <NUM> (i.e. forming a cavity), which can buffer the impact on the inner stent due to compression deformation of the outer stent. Other aspects not specifically described in this embodiment are the same as those in Embodiment <NUM>, such as material of each part of the mitral valve device and provision of skirts.

<FIG> and <FIG> are structure schematic views of rigid connection of the assembly manners optional for the outer valve stent and the inner valve stent of the transapical implantable mitral valve device provided by the fifth embodiment of the present invention. As shown in <FIG> and <FIG>, in this embodiment, the structure of the outer valve stent <NUM> is basically consistent with that of the outer valve stent in Embodiment <NUM>. The difference lies in that in the present embodiment, a set of holes are arranged on the left atrial end and the left ventricular end on a plurality of or each first structure unit of the outer valve stent <NUM>, as shown in <FIG> and <FIG>, a set of second holes <NUM> arranged at the end near the left atrium and a set of first holes <NUM> arranged at the end near the left ventricle, respectively. As in Embodiment <NUM>, in this embodiment, the first holes <NUM> close to the left ventricular end may be distributed near the left ventricular end of the structure unit joint of the adjacent first structure units of the outer valve stent or at the second straight rod, and the second holes <NUM> close to the left atrial end may be distributed at the left atrial end of the structure unit joint.

In this embodiment, the structure of the inner valve stent <NUM> is basically the same as that of the inner valve stent in Embodiment <NUM>; however, in this embodiment, the inner valve stent <NUM> is provided with filamentous connecting structures at both the left atrial end and the left ventricular end, that is, the second filamentous connecting structure <NUM> close to the left atrial end and the first filamentous connecting structure <NUM> close to the left ventricular end. The second filamentous connecting structure <NUM> may extend from the left atrial end of the inner valve stent <NUM> (see <FIG>) or from the middle of the body of the inner valve stent <NUM> (see <FIG>) to form.

In this embodiment, the first filamentous connecting structure <NUM> and the second filamentous connecting structure <NUM> pass through the first hole <NUM> and the second hole <NUM> on the outer valve stent <NUM> from the end near the atrium to the end near the ventricle or from the end near the ventricle to the end near the atrium, respectively. Furthermore, the filamentous connecting structure passing through each set of holes is fixed with the first structure unit with sutures (such as polymer suture), so that the outer valve stent is fixed with the inner valve stent.

In the present embodiment, the number of holes for each set of second holes <NUM> or for each set of first holes <NUM> is between <NUM> and <NUM>, preferably <NUM>. The number of the filamentous connecting structures <NUM> at the left atrial end of the inner valve stent <NUM> ranges between <NUM> and <NUM>, preferably <NUM>. In order to ensure the stability of the valve, the position of the inner valve stent can be moved within a certain range. The number of the filamentous connecting structures <NUM> at the left atrial end of the inner valve stent <NUM> is less than the number of the filamentous connecting structures <NUM> at the left ventricular end of the inner valve stent <NUM>, wherein the number of the filamentous connecting structures <NUM> at the left ventricular end is between <NUM> and <NUM>, preferably <NUM>.

The included angles between the first filamentous structure <NUM> and the second filamentous structure <NUM> and the side wall of the body formed by the first structure units of the outer valve stent are between <NUM> degrees and <NUM> degrees (see <FIG>), so that there is a certain distance (i.e. forming a cavity) between the outer valve stent and the inner valve stent, which can buffer the impact on the inner stent due to compression deformation of the outer stent.

Other aspects not specifically described in this embodiment are the same as those in Embodiment <NUM>, such as materials of various parts of the mitral valve device and provision of skirts, etc..

<FIG> is a structure schematic view of an inner valve stent of a transapical implantable mitral valve device provided by the sixth embodiment of the present invention, and its appearance is similar to that of a surgical biological prosthetic valve. The surgical biological prosthetic valve has good hemodynamic performance, low incidence of thromboembolism, no need for lifelong anticoagulation after operation, and has long-term durability, but the operation is very difficult and traumatic. In view of this situation, the structure of the surgical biological prosthetic valve is modified so that it can be compressed in a sheath; meanwhile, the modified surgical biological prosthetic valve can be used as the inner valve stent to be fixed with the outer valve stent, and the surgical biological prosthetic valve thus can be fixed on the native diseased mitral valve annulus by intervention, which not only exploits the advantages of the surgical biological prosthetic valve, but also reduces the trauma.

In this embodiment, the inner valve stent <NUM> includes a frame <NUM> that is compressible, a valve leaflet structure <NUM> sewn on the frame <NUM>, and an annular sealing ring <NUM> for sealing and stabilizing the structure. In this embodiment, the radius of the inner valve stent <NUM> after radial compression is less than <NUM>, so that the mitral valve device can be loaded into the sheath.

Specifically, the existing surgical valve stent mainly consists of four parts: a valve, a skirt, an annular sealing ring and a metal frame. The annular sealing ring includes an annular sealing ring frame that is made of polymer material and an outer filler; both the metal frame and the annular sealing ring frame are uncompressible. In the present embodiment, the improved surgical biological prosthetic valve as the inner valve stent changes the materials of the metal frame and the annular sealing ring frame into nitinol with hyperelastic properties, meanwhile the shape of the frame is composed of elements with a shape of orthorhombic wave or rhombic shape or the like shape that is compressible.

<FIG> is a schematic view of a connection manner between the inner valve stent and the outer valve stent of the transapical implantable mitral valve device provided by the sixth embodiment of the present invention. As shown in <FIG>, in this embodiment, the periphery of the annular sealing ring <NUM> is provided with filamentous connecting structures <NUM>. In this embodiment, the structure of the outer valve stent <NUM> is basically the same as that in Embodiment <NUM>, but in this embodiment, the outer valve stent <NUM> has no first hole at the end near the left ventricular, and sets of second holes <NUM> are provided only at the end near the left atrial. As shown in <FIG>, the filamentous connecting structure <NUM> passes through the second hole <NUM> of the outer valve stent <NUM>, and the filamentous connecting structure <NUM> is fixed with the outer valve stent <NUM> with the suture <NUM>, so that the outer valve stent <NUM> and the inner valve stent <NUM> are fixed. Alternatively, the number of second holes <NUM> in each set is between <NUM> and <NUM>, preferably <NUM>.

In the present embodiment, the acute angle between the filamentous connecting structure <NUM> and the axial direction of the mitral valve device ranges from <NUM> degrees to <NUM> degrees, so that there is a certain distance between the inner valve stent and the outer stent after connection (i.e., forming a cavity), which can buffer the impact on the inner stent due to the compression deformation of the outer stent.

In the present embodiment, the number of the filamentous connecting structures <NUM> ranges between <NUM> and <NUM>, correspondingly, the number of sets of the second holes is between <NUM> and <NUM>, and the number of the both is the same. In the present embodiment, the shape of the second hole <NUM> can be a circle, a rounded rectangle and other shapes. In this embodiment, the shape of the filamentous connecting structure <NUM> may be linear, circular arc, sinusoidal wave or irregular waves.

Like the above embodiments, in the present embodiment, a layer of outer skirt is wrapped on the inner surface and/or outer surface of the outer valve stent <NUM>, and is fixed by suturing, pressing or bonding to avoid peripheral leakage.

<FIG> is a schematic view of a connection manner between the inner valve stent and the outer valve stent of a transapical implantable mitral valve device provided by the seventh embodiment of the present invention. As shown in <FIG>, in the present embodiment, the structure of the inner valve stent <NUM> is basically the same as that of Embodiment <NUM>, but there is no filamentous connecting structure. In the present embodiment, the structure of the outer valve stent <NUM> is basically the same as that of the outer valve stent in Embodiment <NUM>, and a clip structure <NUM> for clamping the annular sealing ring <NUM> of the inner valve stent is provided at the end of the first structure unit near the left atrial. In this embodiment, the annular sealing ring <NUM> of the inner valve stent <NUM> is clamped on the clip structure <NUM> of the outer valve stent <NUM>, and the outer valve stent <NUM> and the inner valve stent <NUM> are fixed by means of size matching or suture or glue or the like. There is a certain distance between the inner valve stent and the outer stent (i.e. forming a cavity), which can buffer the impact on the inner stent due to compression deformation of the outer stent.

Alternatively, connection of the outer valve stent and the inner valve stent can be fixed by other mechanical connecting structures such as metal wires or metal bayonets, suture, glue or other connection methods. The number of the mechanical connecting structures such as metal wires or metal bayonets ranges between <NUM> and <NUM>.

As the above embodiments, in the present embodiment, a layer of outer skirt is wrapped on the inner surface and/or outer surface of the outer valve stent <NUM>, and is fixed by suturing, pressing or bonding to avoid peripheral leakage.

When the mitral valve device in each embodiment of the present invention is used, it is loaded on the matched delivery system: the stents are straightened by pulling pull rings at the left ventricular end and left atrial end of the stent, and the mitral valve device is put into the sheath of the delivery system by reducing the outer diameter. With the delivery system, the mitral valve device is implanted into the diseased mitral position of human body through the apex, the outer valve stent of the valve device is anchored at the native mitral valve annulus of human body, and the valve leaflets on the inner valve stent of the valve device open and close under the action of blood dynamics to replace the effect of the native mitral valve.

It can be seen that the transapical implantable mitral valve device provided in the above embodiments connects the outer valve stent with the inner valve stent in different manners, and the design of double layers and incomplete fixation of the inner and outer valve stents makes the outer valve stent and the inner valve stent both relatively fixed and can move independently, so as to ensure that the mitral valve device is not affected by the irregular contour of the diseased mitral valve, the ideal contour is always maintained to ensure functions and avoid leakage of the valve. Moreover, the U-shaped structure unit and S-shaped structure unit arranged in the transapical implantable mitral valve device provided in the above embodiments can be accurately transported to and firmly anchored at the position of the diseased mitral valve. Moreover, the transapical implantable mitral valve device provided in the above embodiments can provide a platform for interventional therapy for the surgical-type mitral valve device.

Claim 1:
A transapical implantable mitral valve device, it comprises:
an outer valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising an outer valve stent body that is composed of a plurality of first structure units arranged in a circumferential direction, and an anchoring unit that is disposed on the outer valve stent body for anchoring the mitral valve device within a human body; an inner surface and/or an outer surface of the outer valve stent body being covered with an outer skirt;
characterised in that an inner valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is disposed inside the outer valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and interconnected with the outer valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), and a cavity being formed between the outer valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and the inner valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>); and a valve leaflet structure (<NUM>, <NUM>, <NUM>) is disposed inside the inner valve stent (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) to form a prosthetic valve;
whereby the anchoring unit comprises a U-shaped structure unit (<NUM>, <NUM>) and an
S-shaped structure unit (<NUM>, <NUM>), wherein the S-shaped structure unit (<NUM>, <NUM>) is arranged at a left ventricular end of the outer valve stent body; the S-shaped structure unit (<NUM>, <NUM>) is formed by bending upwards and then bending downwards to form a folded structure, and the outer side of the S-shaped structure unit (<NUM>, <NUM>) is in contact with an inner side of the mitral valve leaflet for fixing with the mitral valve leaflet.