Balloon dilatation valve with clamping piece

Abstract

The invention discloses a balloon dilatation valve with a clamping piece, and relates to the technical field of medical instruments, the balloon dilatation valve comprises a valve support capable of expanding in the radial direction, a functional valve arranged on the inner side of the valve support and the clamping piece connected to the valve support; the clamping piece can move relative to the valve support and is matched with the valve support to clamp the autologous valve leaflet, the clamping piece comprises a plurality of rebounding components with deformation parts, and the rebounding components are converted between bunchy lines and fan-shaped distribution through deformation of the deformation parts. The valve stent further comprises a control sleeve which is used for restraining the clamping piece in the conveying state and adjusting and controlling the included angle between the clamping piece and the valve stent by changing the restraining degree. The mitral valve anterior leaflet is clamped and shortened through the clamping piece, and left ventricular outflow tract obstruction is effectively prevented; meanwhile, stable clamping force is formed by the clamping piece and the valve support, and displacement of the valve is prevented; in addition, the delivery system is small in outer diameter, good in trafficability and suitable for patients with small mitral valve openings and small heart cavities.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and specifically to a balloon dilatation valve with a clamping element. Background Technology

[0002] Mitral stenosis is a common heart disease. Its main cause is rheumatic, which is prevalent in developing countries with underdeveloped economies. It is still prevalent in small towns and remote mountain villages in my country. Another important cause is calcification, which is often accompanied by mitral valve annulus calcification (MAC). It is more common in elderly patients, and the number of patients with this cause is increasing with the aging population.

[0003] Traditional treatments for mitral stenosis primarily include percutaneous mitral balloon dilation and surgical mitral valve replacement. While percutaneous mitral balloon dilation is currently the preferred treatment recommended by guidelines, postoperative valvular disease continues to progress, resulting in a 5-year restenosis rate of 30%-50%, requiring repeated surgeries. Furthermore, in practice, most patients with severe calcification or regurgitation are not suitable candidates for this procedure. Surgical mitral valve replacement, although improving hemodynamics, is highly invasive and carries significant risks. For elderly patients, surgery is often not tolerated; therefore, transcatheter mitral valve replacement is a promising development direction for elderly patients with mitral stenosis.

[0004] Currently, there are no transcatheter valve replacement devices specifically designed for mitral stenosis, either domestically or internationally. All transcatheter mitral valve replacement devices currently in clinical trials are designed for mitral regurgitation. For patients with mitral stenosis, these valves are too large, easily causing left ventricular outflow tract obstruction. The delivery system is also too large, making it prone to vascular damage. Furthermore, the device's anchoring mechanism is not suitable for mitral stenosis patients. Another approach is to try using interventional valves (balloon-dilated valves) designed for aortic valve replacement in mitral stenosis patients. However, these valves lack additional anchoring devices and rely solely on radial support for fixation, which can easily lead to valve displacement. Since these devices also easily cause left ventricular outflow tract obstruction, and because the mitral valve annulus is not circular and has a triangular region, these circular valves are prone to paravalvular leakage.

[0005] The two devices mentioned above have not been widely used in clinical practice, and there are only case reports of selective cases. Therefore, there is currently a clinical need for transcatheter replacement artificial valves specifically for mitral stenosis to solve the problems that non-dedicated valves can easily cause outflow tract obstruction, valve displacement, and paravalvular leakage. Summary of the Invention

[0006] The purpose of this invention is to provide a balloon dilatation valve with a clamping device, which solves the problems that valve displacement and left ventricular outflow tract obstruction are easily caused by relying solely on radial support force for fixation without additional anchoring devices.

[0007] The present invention solves the above-mentioned technical problems through the following technical solutions, the present invention comprising:

[0008] Radially expandable valve stent;

[0009] A functional valve located inside the valve stent;

[0010] A clamping member connected to the valve stent, the clamping member being movable relative to the valve stent and cooperating with the valve stent to clamp the autologous valve leaflet.

[0011] Optionally, the valve stent is made of cobalt-chromium alloy or stainless steel, and is a hollow cylindrical shape composed of multiple interconnected polygonal grid units.

[0012] In one embodiment, the functional valve is composed of bovine pericardium, porcine pericardium, or a polymeric valve.

[0013] Preferably, the clamping member includes a plurality of spring-loaded components with deformable portions, the deformable portions being located at the connection between the spring-loaded components and the valve stent;

[0014] The spring-loaded component transforms between axially contracted bundle-like lines and radially expanded fan-shaped distribution through the deformation of the deformation section.

[0015] It should be noted that the deformable part is the core joint for the clamping member to perform the clamping action. Its preset memory shape allows the clamping member to spontaneously transition from the longitudinal arrangement in the conveying state to the reverse arrangement in the working state when it is not constrained by the control sleeve.

[0016] Preferably, it further includes a movable control sleeve for constraining the clamping member in the conveying state and controlling its deformation by changing the degree of constraint on the clamping member.

[0017] Optionally, the control sleeve is a polymer hollow thin-walled flexible tube.

[0018] Preferably, by changing the degree to which the control sleeve accommodates the clamping member, the angle between the clamping member and the valve stent varies between 0° and 180°.

[0019] When the control cannula fully restrains the clamping element, the angle between the clamping element and the valve stent is close to 0°, and the two form a bundle-like line. As the control cannula is gradually withdrawn, the clamping element gradually reverses, forming an initial angle of approximately 90° with the valve stent, establishing a wide radial capture window in the left ventricle. When the control cannula fully releases the clamping element, the angle can reach 180°, and the clamping element and the valve stent form a strong clamping structure, locking the autologous leaflet between them.

[0020] Preferably, the deformation vectors of the deformable portions of the plurality of rebound components are set to be different, such that the plurality of rebound components are distributed radially in an umbrella shape with the central axis of the valve stent as the reference in a fan-shaped distribution.

[0021] Preferably, the end of the springback component away from the deformation portion has a passivation portion.

[0022] It should be noted that the passivation part is bent or passivated to avoid scratching or perforating the heart tissue (such as mitral valve leaflets, chordae tendineae, and ventricular septum) during the flipping or clamping process of the spring-loaded part, thereby improving the implantation safety of the device.

[0023] Preferably, it also includes a delivery system comprising an inflatable balloon and a catheter connected to the proximal end of the balloon;

[0024] In the delivery state, the valve stent is compressed and attached to the outside of the balloon. In the working state, the balloon is inflated, causing the valve stent to be stretched and radially expanded.

[0025] It should be noted that when the balloon is emptied, it is in a soft, thin membrane state. After fluid is filled into the balloon through the catheter, the balloon fully expands, and its outer diameter is similar to the inner diameter of the valve stent when it is in working condition.

[0026] Preferably, the catheter contains a hollow thin catheter in the central axis of the balloon cavity so that the balloon can always be in a straight state, and the catheter has protrusions at both ends of the balloon. The distance between the two protrusions is 1-4 mm greater than the length of the valve stent in the delivery state, for fixing the valve stent in the compressed state.

[0027] Preferably, the balloon near the clamping member has a notch for receiving the clamping member.

[0028] Preferably, the upper half of the valve stent has a skirt on its outer periphery.

[0029] Preferably, the outer side of the skirt is provided with a paravalvular leakage prevention component, which consists of two sets of expandable polymer strips arranged along the longitudinal axis of the valve stent. The paravalvular leakage prevention component maintains an angle difference of 50°-80° with the clamping component in cross-section, which can target and block paravalvular leakage at the junction of the inner and outer surfaces of the mitral valve after the valve stent is implanted.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. This invention achieves a high degree of unity between multi-dimensional shape transformation and strong anchoring by setting up a clamping component with shape memory and cooperating with a control sleeve: it can achieve a large-angle reversal switching of 0°-180° in the axial direction, and can achieve dynamic expansion from a compact bundle shape to an expanding umbrella shape in the cross section; while significantly reducing the delivery profile and improving the convenience of retrieval and delivery, it greatly increases the capture range and clamping density of autologous valve leaflets, so that the clamping component can cooperate with the valve stent to form a more stable clamping force, effectively improving the fixation reliability of the overall device under ventricular high pressure environment and reducing the risk of displacement.

[0032] 2. This invention uses a clamping device to clamp the anterior leaflet of the mitral valve, shortening it and fixing it to the outside of the valve stent, thus preventing the anterior leaflet of the mitral valve from bulging into the left ventricular outflow tract during systole, thereby effectively reducing the risk of left ventricular outflow tract obstruction, and is especially suitable for patients with mitral stenosis with small heart chambers.

[0033] 3. Through the design of balloon-expandable valve stents, the valve stent is short, with only a catheter in the proximal section. This section of the delivery system is thinner and softer, making it easier to bend in the narrow atrial space and automatically maintain coaxiality with the guidewire, avoiding the need for complex delivery system adjustment designs. This is something that self-expanding valves (which require long stents and rigid delivery systems) cannot do.

[0034] 4. Compared to ordinary balloon dilatation valves, the control cannula can enhance the fixation of the valve stent on the balloon, making it less prone to dislodgement. At the same time, the flexible design does not mechanically affect the radial morphological changes of the valve delivery system. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the conveying state of the present invention;

[0036] Figure 2 for Figure 1 A three-dimensional structural diagram of the medium-speed conveyor system;

[0037] Figure 3 This is a structural schematic diagram of the working state of the present invention;

[0038] Figure 4 This is a schematic diagram of the extended state of the present invention;

[0039] Figure 5 for Figure 4 A schematic diagram of a half-section structure;

[0040] Figure 6 A schematic diagram of the structure for adding components to prevent periocular leakage.

[0041] The numbers in the diagram represent:

[0042] 1-Control cannula; 2-Valve stent; 3-Functional valve; 4-Skirt; 5-Clamping element; 51-Passivation part; 52-Deformation part; 61-Protrusion; 62-Catheter; 63-Balloon; 64-Notch; 7-Component to prevent paravalvular leakage; 71-Recess. Detailed Implementation

[0043] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0044] This embodiment provides a technical solution: a balloon dilation valve with a clamping element, such as... Figures 1-5 As shown, it includes a valve stent 2, a functional valve 3, a deformable clamping member 5, a control sleeve 1, and a delivery system.

[0045] It should be noted that the valve stent 2 is made of high-hardness rigid metal materials, such as cobalt-chromium alloy and stainless steel. The whole is a hollow cylinder, which is composed of multiple polygonal (such as hexagonal and rhomboid) grid units connected to each other. The polygonal grid design, through reasonable geometric arrangement, can ensure that the stent has good radial compression performance when under pressure (so as to facilitate the insertion of the control sleeve 1), and can provide uniform circumferential support force after expansion.

[0046] Preferably, in order to reduce the possibility of left ventricular outflow tract obstruction, the lower grid area of ​​the valve stent 2 is larger than the upper grid area, so that more blood flow can pass through the grid.

[0047] The functional valve 3 is located inside the valve stent 2 and the two can be connected by sutures. The functional valve 3 is sutured into the upper half of the valve stent 2 and consists of three leaflets made of bovine pericardium, porcine pericardium, or polymer valves. During the process of the valve stent 2 switching from the delivery state (strip-shaped) to the working state (cylindrical), the functional valve 3 expands radially with the stent, forming three movable crescent-shaped leaflet structures to guide unidirectional blood flow during cardiac pulsation.

[0048] In this embodiment, "upper" refers to the side facing the atrium when the valve device is implanted into the mitral valve of the heart, "lower" refers to the side facing the ventricle, "proximal" refers to the end of the valve device that is closer to the outside (operator) after it is loaded into the delivery system, "distal" refers to the end facing the patient's heart, "medial" refers to the direction towards the central axis of the valve stent 2, and "lateral" refers to the direction away from the central axis of the valve stent 2.

[0049] Preferably, a skirt 4 is provided around the outer periphery of the upper half of the valve stent 2. The skirt 4 is a polymer film that can be sutured onto the valve stent 2 to prevent paravalvular leakage. The lower half of the valve stent 2 has a hollowed-out area without the covered skirt 4, which allows blood flow to reduce the occurrence of left ventricular outflow tract obstruction.

[0050] In the description of this embodiment, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0051] like Figure 4 and Figure 5 As shown, the clamping member 5 includes multiple spring-loaded components made of shape memory metal. The spring-loaded components are connected to the outer side of the lower end of the valve stent 2. The spring-loaded components have planar convergence and axial deformability.

[0052] Furthermore, the connection end between the rebound component and the valve stent 2 is provided with a deformation part 52 that can be rotated at a large angle. The deformation part 52 is the core joint for realizing the clamping action. Its preset memory shape allows the clamping part 5 to spontaneously transition from the bundle-shaped lines in the delivery state to the fan-shaped distribution in the working state when it is not constrained by the control sleeve 1.

[0053] In order to maximize the capture range, the deformation vector (direction) of the deformation part 52 of each rebound component in this embodiment is designed to be different. Under the guidance of the deformation part 52, the multiple rebound components are not simply arranged in parallel after release, but present a fan-shaped distribution (or umbrella-shaped radial distribution) with the central axis of the valve stent 2 as the reference.

[0054] Preferably, the end of the spring-loaded component away from the deformation portion 52 has a passivation portion 51, which is bent or passivated to avoid scratching the heart tissue when the spring-loaded component flips over.

[0055] In the delivery state, the valve stent 2 and the clamping member 5 are both inserted into the control sleeve 1. The deformed part 52 and the passivated part 51 (bent and shaped) will be smoothed out, and each rebound component and the valve stent 2 will extend into a bundle-like line in the axial direction, such as Figure 1 As shown, this facilitates compression and delivery into smaller channels; in the working state, each rebound component overlaps with the valve stent 2 axially to form a clamp, which holds the autologous valve leaflet, with the upper ends converging together and the lower ends separating to form a fan-shaped distribution covering the outer periphery of the valve stent 2, as shown. Figure 4 As shown.

[0056] The control sleeve 1 is a hollow, thin-walled polymer flexible tube that can tightly accommodate the valve stent 2 and clamping member 5 in the delivery state within the inner cavity of the tube. When the valve stent 2 is inserted to the designated position, the control sleeve 1 is retracted, changing the degree of containment of the clamping member 5. The clamping member 5 returns to its free working state. When the control sleeve 1 no longer covers the deformable part 52 of the clamping member 5, the various rebound components of the clamping member 5 lose their constraint and undergo axial deflection. This allows the angle between the rebound components of the clamping member 5 and the valve stent 2 to vary between 0° and 180°. The rebound components of the clamping member 5 and the valve stent 2 form multiple clamps, ultimately achieving the clamping and fixation of the autologous valve leaflet through the action of the rebound components and the valve stent 2.

[0057] The delivery system includes a cylindrical balloon 63. When the balloon 63 is emptied, it is in a soft, thin membrane state. A catheter 62 is connected to the proximal end of the balloon 63, through which fluid can be filled into or removed from the balloon 63. When the balloon 63 is fully inflated, its outer diameter is similar to the inner diameter of the valve stent 2 when it is in the working state. When the balloon 63 is emptied, its outer diameter is smaller than the inner diameter of the valve stent 2 when it is in the delivery state.

[0058] In the delivery state, the valve stent 2 is compressed into a thin strip shape and maintains that shape (e.g., Figure 1 The valve stent 2 in the middle is in the form of a thin strip. It is compressed and attached to the outside of the deflated balloon 63. When the balloon 63 is inflated, the balloon 63 expands, and the valve stent 2 is stretched into its designed cylindrical state, while maintaining a high radial support force and not easily collapsing due to external forces.

[0059] The distal end of the catheter 62 continues to travel within the lumen of the balloon 63, and this journey contains two protrusions 61. The distance between the two protrusions 61 is slightly greater than the length of the valve stent 2, and the outer sides of the two protrusions 61 extend to the periphery of the valve stent 2. The two protrusions 61 can restrain the valve stent 2 in its thin strip shape and prevent the valve stent 2 from detaching from the balloon 62 during delivery.

[0060] Furthermore, the protrusion 61 near the clamping part 5 does not radially encircle the balloon 63; instead, it has a notch 64 in the circumferential direction of the cross-section of the balloon 63, such as... Figure 2 As shown. The notch 64 allows the valve stent 2 to be installed on the balloon 63, accommodating its clamping member 5 so that it does not rest on the protrusion 61, thus preventing the overall device from being too large for transport.

[0061] The control cannula 1 can enhance the compression of the valve stent 2 and prevent the valve stent 2 from detaching from the balloon 63. The control cannula 1 is a soft film, so it does not affect the radial mechanical changes of the valve stent 2's matching balloon 63 and catheter 62, and therefore does not affect the coaxiality of the overall device with the mitral valve during surgery.

[0062] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] Furthermore, two anti-valve leakage components 7 are provided on the outer side of the skirt 4. These two anti-valve leakage components 7 are located on opposite sides of the clamping member 5. The anti-valve leakage components 7 are expandable polymer sheets, and maintain an angle difference of 50°-80° with the clamping member in cross-section. Figure 6 As shown, it can target and seal paravalvular leakage at the junction of the mitral valve and its interior / exterior after the implantation of the valve stent 2. Additionally, a recess 71 corresponding to the clamping member 5 is provided on the skirt 4.

[0064] The paravalvular leakage prevention component 7 forms a flexible sealing barrier on the outside of the valve stent through its expandable polymer sheet structure, achieving precise targeted sealing at the junction of the mitral valve's inner and outer surfaces. At the same time, the component can adaptively fit irregular gaps, assist in stabilizing the valve stent, reduce postoperative paravalvular leakage and related complications, and promote endothelialization and tissue healing, thereby significantly improving the success rate and long-term efficacy of transcatheter valve replacement surgery.

[0065] The specific surgical steps are as follows:

[0066] 1. The valve stent 2 and the clamp 5 are loaded together in the inner cavity of the control cannula 1. At this stage, since the clamp 5 is made of a material with shape memory properties, it is radially constrained by the inner wall of the control cannula 1 and is in a compact bundle-like line, which reduces the outer diameter of the delivery system and ensures that the device can pass smoothly through narrow veins.

[0067] 2. It is inserted through the femoral vein, punctured through the interatrial septum into the left atrium, and further delivered to the predetermined position in the left ventricle;

[0068] 3. Slowly retract the control cannula 1. When the control cannula 1 is withdrawn from the deformable part 52 of the clamping member 5, the clamping member 5 undergoes axial reversal movement using the elasticity of the material. At this time, the clamping member 5 forms an initial angle of approximately 90° with the valve stent 2, transforming from a "bundle-like line" to a "vertical unfolding". In effect, a large radial capture window is established in the left ventricle, which significantly increases the probability and physical space for capturing the autologous valve leaflet.

[0069] 4. Under ultrasound guidance, rotate and adjust the axis of the delivery system so that the clamping element 5 is aligned with the anterior leaflet of the mitral valve. As the control cannula 1 is further withdrawn, the clamping element 5 not only deflects axially but also expands from a compact bundle to a fan-shaped distribution in cross-section. Multiple separately distributed rebound components form a dense "claw-shaped" clamp, ensuring that the clamping element can cover a wider leaflet edge and avoiding leaflet tearing or slippage that is easily caused by single-point clamping. Subsequently, by withdrawing the control cannula 1 further, the clamping element 5 is completely released from clamping the anterior leaflet of the mitral valve. Figure 3 As shown;

[0070] 5. The balloon 63 is inflated through the catheter 62. As the balloon 63 expands radially, the valve stent 2 is forcibly stretched to the preset cylindrical working state (e.g., Figure 4 As shown); the valve stent 2 expands radially outward, while the clamping member 5 with shape memory function generates inward restoring stress; the autologous leaflet is firmly locked between the outwardly expanding valve stent 2 and the inwardly rebounding clamping member 5. The "coupling effect" of the internal and external stresses not only increases the friction but also forms a set of physical locking structures to ensure that the overall device does not produce axial displacement under the high pressure environment of the heart beating.

[0071] 6. After confirming that the valve position is fixed and there is no paravalvular leakage, empty the balloon 63, reduce its outer diameter, and remove it from the body along with the catheter 62 and control cannula 1.

[0072] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.

Claims

1. A balloon dilatation valve with a clamping element, characterized in that, include: Radially expandable valve stent (2); The functional valve (3) is located inside the valve stent (2). A clamping member (5) is connected to the valve stent (2), the clamping member (5) is movable relative to the valve stent (2), and cooperates with the valve stent (2) to clamp the autologous leaflet.

2. The balloon dilatation valve with clamping element according to claim 1, characterized in that, The clamping member (5) includes a plurality of spring-loaded components having deformable portions (52), the deformable portions (52) being located at the connection between the spring-loaded components and the valve stent (2); The spring-loaded component transforms between axially contracted bundle-like lines and radially expanded fan-shaped distribution through the deformation of the deformation part (52).

3. The balloon dilatation valve with clamping element according to claim 2, characterized in that, It also includes a movable control sleeve (1) for constraining the clamp (5) in the transport state and controlling its deformation by changing the degree of constraint on the clamp (5).

4. The balloon dilatation valve with clamping element according to claim 3, characterized in that, By changing the degree to which the control sleeve (1) accommodates the clamping member (5), the angle between the clamping member (5) and the valve stent (2) varies between 0° and 180°.

5. The balloon dilatation valve with clamping element according to claim 2, characterized in that, The deformation vectors of the deformation portions (52) of the multiple rebound components are set to be different, so that the multiple rebound components are distributed radially in an umbrella shape with the central axis of the valve stent (2) as the reference in a fan-shaped distribution.

6. The balloon dilatation valve with clamping element according to claim 2, characterized in that, The end of the springback component away from the deformation portion (52) has a passivation portion (51).

7. The balloon dilatation valve with clamping element according to claim 1, characterized in that, It also includes a delivery system comprising an inflatable balloon (63) and a catheter (62) connected to the proximal end of the balloon (63). In the delivery state, the valve stent (2) is compressed and attached to the outside of the balloon (63). In the working state, the balloon (63) is inflated, causing the valve stent (2) to be stretched and radially expanded.

8. The balloon dilatation valve with clamping element according to claim 7, characterized in that, The catheter (62) has protrusions (61) at both ends of the balloon (63), and the distance between the two protrusions (61) is greater than the length of the valve stent (2) in the delivery state; the balloon (63) near the clamp (5) is provided with a notch (64) for accommodating the clamp (5).

9. The balloon dilatation valve with clamping element according to claim 1, characterized in that, The upper half of the valve stent (2) is provided with a skirt (4) on its outer periphery.

10. The balloon dilatation valve with clamping element according to claim 9, characterized in that, The outer side of the skirt (4) is provided with a paravalvular leakage prevention component (7), which consists of two sets of expandable polymer strips arranged along the longitudinal axis of the valve stent (2). The paravalvular leakage prevention component (7) maintains an angle difference of 50°-80° with the clamping component (5) in cross-section.

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