Patent Description:
With medical advances, conventional high-risk surgeries are being gradually replaced by minimally invasive catheter procedures. At present, minimally invasive techniques mainly developed and applied in markets include indirect annuloplasty, direct annuloplasty, edge-to-edge repair, and chordae tendineae repair.

The edge-to-edge repair gradually becomes mature in clinical practices of surgical treatment for mitral valve regurgitation and has a desirable treatment effect.

Valve clamp devices developed based on the technical principle of the surgical edge-to-edge suture of the valve are currently most recognized due to high safety, simple technical principle, and high feasibility.

<CIT> describes a clip treatment tool for an endoscope, which is used, for example, to close a wound and to stop bleeding in a living body. A clip treatment tool includes a clip unit and a treatment tool body. The clip unit includes a fixing pin, and a clip body, which has a first clip piece and a second clip piece. The arm portions of the two clip pieces open in accordance with movement of the clip body from the proximal end side toward the distal end side, and the arm portions of the two clip pieces close in accordance with movement of the clip body from the distal end side toward the proximal end side.

According to the prior art, to use a valve clamp device, it needs a delivery assembly for delivering the valve clamp device to a target location on the heart. Then, the valve clamp device may be fixed there and stay in the heart as an implant, while the delivery assembly may be relatively separated from the valve clamping device by means of a clutch mechanism. However, existing clamps are restricted in length to some extent, because they need to pass through narrow channels and make a turn, which limits a capturing distance. Moreover, existing connecting rod mechanisms for driving the clamp also limit a turning angle of the clamp, which makes it more difficult to capture a valve leaflet. To sum up, it is desired to improve both the driving means and the separating means of the clamp.

In order to solve the above-mentioned technical problems, the present disclosure provides a system for clamping a tissue, which may include an improved mechanism to capture a valve leaflet more stably and reliably.

The invention is a heart valve clamp device as defined by the features of the independent claim.

Specifically, the present disclosure employs the following solutions:.

A system for clamping a tissue includes:.

Further, the clamp mechanism may include the pair of closure members and a pair of capture members, each capture member in one-to-one correspondence with a respective one of the closure members; and the pair of closure members may include closure connecting portions and the closure clamping portions arranged to cooperate with the pair of capture members to clamp the tissue; and
the guide slots may be formed in the closure connecting portions.

Further, the support mechanism may include a fixed connecting assembly, and the slot driving members at least partially located in the guide slots may be provided on the fixed connecting assembly, and the drive assembly may be connected to the two closure clamping portions, and may be arranged to allow each of the slot driving members to slide in the respective one of the guide slots when the drive assembly moves relative to the fixed connecting assembly.

Further, each of the guide slots may include at least two slot regions in communication with each other, and a radian of the first slot region of the two slot regions may be greater than a radian of the second slot region of the two slot regions.

Further, each of the guide slots may further include a third slot region in communication with the second slot region and having a radian greater than the radian of the second slot region, and the second slot region may be located between the first slot region and the third slot region, respectively.

Further, the clutch mechanism may include an actuator rod connected to the drive assembly in a non-rotatable and axially separable manner such that rotation of the actuator rod directs the drive assembly to move axially; and
the actuator rod may be configured to disengage the clutch mechanism from the fixing device when the actuator rod is moved proximally.

Further, the support mechanism may include a fixed connecting assembly and the drive assembly which may be moveable relative to the fixed connecting assembly, and the fixed connecting assembly may include a base clutching end;.

Further, the coupling seat may include a coupling seat connecting end, a coupling seat clutching end, and a coupling seat inner cavity defined through the coupling seat, the engagement member may be provided in the coupling seat inner cavity, the coupling seat clutching end may be connected to the base clutching end via the engagement member, and the coupling seat connecting end may be connected to a delivery device.

Further, the delivery control device may further include a manipulation wire for controlling capture members of the clamp mechanism to open and close, the engagement member may include a manipulation wire limiting groove for preventing separation of the manipulation wire when the coupling seat is connected to the base clutching end.

Further, the fixed connecting assembly may include a base housing with a base inner cavity formed therein, a base threaded portion may be provided in the base inner cavity, the drive assembly may include a drive shaft, the drive shaft may include a drive shaft threaded portion cooperating with the base threaded portion, and wherein a lead angle at which the base threaded portion is cooperating with the drive shaft threaded portion may be less than a friction angle.

The present disclosure achieves the following beneficial effects.

In order to illustrate the technical solutions in the embodiments of the present disclosure more clearly, the drawings for the description of the embodiments or the prior art are briefly described below. Apparently, the accompanying drawings described below are merely some embodiments of the present disclosure, and those of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

The technical solutions of the embodiments of the present disclosure are clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are merely a part rather than all of the embodiments of the present disclosure. In the description of the embodiment, the term "proximal end" refers to an end proximal to the operator, while the term "distal end" refers to an end distal to the operator. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without making inventive efforts shall fall within the scope of protection of the present disclosure.

In an embodiment, a system for clamping a tissue is provided, specifically including:.

The clamp mechanism <NUM> includes a pair of closure members <NUM>. A guide slot <NUM> including at least a nonlinear segment is formed in each of the pair of closure members <NUM>. The support mechanism <NUM> is provided with slot driving members <NUM>, each of which is at least partially located in one of the guide slots <NUM>. Each of the slot driving members <NUM> is relatively slidable in the one of guide slots <NUM>, so as to drive two closure clamping portions <NUM> to move towards or away from each other.

Specifically, the clamp mechanism <NUM> in the example includes a pair of closure members <NUM> and a pair of capture members <NUM>, each capture member <NUM> in one-to-one correspondence with one of the closure members <NUM>. The closure members <NUM> can be opened and closed by the drive assembly <NUM>. The capture members <NUM> can be opened and closed by a manipulation wire <NUM>. In order to clamp the tissue, the closure members <NUM> maybe extended inward, while the capture members <NUM> may be extended outward, to achieve cooperation with each other. The system may be used for clamping of a heart valve leaflet as an implementation to describe a specific working principle of the fixing device for clamping the tissue. Referring to <FIG>, the fixing device in the example is delivered to a target location in a heart by the delivery control device. Specifically, the delivery control device includes a push shaft <NUM> for introducing the fixing device to the target location and a clutch mechanism <NUM> for allowing the push shaft <NUM> and the fixing device to be separably connected. In one example of the present disclosure, the push shaft <NUM> may be a rod-like body with an inner cavity or a hollow tubular body, which is made of a biocompatible material. In the example, an engagement shaft <NUM> is shaped as a circular rod or a circular tube. The push shaft <NUM> has a smooth surface to avoid damage to a valve leaflet or a chordae tendineae. The push shaft <NUM> first enters a surgical channel together with a catheter <NUM>. After reaching a vicinity of the lesion, the push shaft <NUM> may be advanced out of the catheter <NUM> to deliver the fixing device to the mitral valve. Preferably, a distal end of the fixing device, namely a distal end of the clamp mechanism <NUM>, may be coated with a protective covering layer. The protective covering layer is made of a biocompatible material and completely coats a periphery of the clamp mechanism <NUM>. The protective covering layer can prevent a damage of the device to the tissue. When the fixing device stays in the heart as an implant, an outer surface of the fixing device can be completely protected by the protective covering layer.

After the fixing device arrives at the valve, regions of the anterior valve leaflet and the posterior valve leaflet of the heart valve (which cannot be properly closed) are clamped by cooperation of the closure members <NUM> and the capture members <NUM> of the clamp mechanism <NUM> in the embodiment. As a result, the leaflets that cannot be closed properly are clamped together, such that the mitral valve can be tightly closed or closed with a smaller opening, thereby treating or relieving "mitral regurgitation".

After the mitral valve is clamped, the fixing device is separated from the delivery control assembly by the clutch mechanism <NUM>. The fixing device remains at the lesion to fix the valve.

The guide slot <NUM> includes at least two guide slot regions (namely a first slot region and a second slot region) in communication with each other. A radian of the first slot region may be greater than a radian of the second slot region. <FIG> illustrates an implementation of the guide slot according to a first example of the present disclosure. Herein, the guide slot may be divided into a first slot region, a second slot region, and a third slot region extending from a distal end to a proximal end. In the example, the first slot region and the third slot region are arc segments, while the second slot region is a linear segment. With the arc feature, the turning angle can be changed in a larger range. Meanwhile, it has a small torque with a nonlinear variation in a small range, and a dead point where the torque is zero. With a linear feature, the torque is large, and changes linearly and stably. It can be changed in a larger range without a dead point, but the turning angle can be changed in a smaller range. Therefore, with the guide slot <NUM> defined as a first curved slot region, a second linear slot region, and a third curved slot region, the closure member <NUM> may experience a relatively smaller torque and a faster change process during opening at an initial position and at a position with a maximum opening angle, compared with the intermediate capturing process, and meanwhile has a relative slow angular change at the capturing process, , thereby facilitating fine operation by the operator, and improving system reliability.

Referring to <FIG>, the slot driving member <NUM> is shaped as a circular push shaft, and located in the guide slot <NUM>. A width of the guide slot <NUM> is matched with an outer diameter of the slot driving member <NUM>. At an initially unopened position, the slot driving member <NUM> is located at the most proximal end, as shown in <FIG>, namely the most proximal end of the third slot region. A distance between the slot driving member <NUM> and a closure member matching portion <NUM> is h1. During opening of the closure clamping portion <NUM>, the slot driving member <NUM> slides in the third slot region toward the distal end, and enters the second slot region from a distal-most end of the third slot region. In such a case, the closure clamping portion <NUM> is rotated by an angle of α1. When the slot driving member <NUM> further slides to a distal-most end of the second slot region, namely at an extreme end of the linear segment, the closure clamping portion <NUM> is rotated by an angle of α2. A distance between the slot driving member <NUM> and the closure member matching portion <NUM> is h2, as shown in <FIG>. When the slot driving member <NUM> further slides toward a distal end in the first slot region and arrives at a distal-most end of the guide slot <NUM>, the closure clamping portion <NUM> is rotated by an angle of α3. Herein, the α1, the α2, the α3, the h1, and the h2 can be selected and ranged according to an actual need. In an embodiment, the angle α1 is preferably in a range of <NUM>° to <NUM>°, more preferably in a range of <NUM>° to <NUM>°, and even more preferably <NUM>°. The angle α2 is preferably in a range of <NUM>° to <NUM>°, more preferably in a range of <NUM>° to <NUM>°, and even more preferably <NUM>°. The angle α3 is preferably in a range of <NUM>° to <NUM>°, more preferably in a range of <NUM>°to <NUM>°, and even more preferably <NUM>°. The distance h1 is preferably in a range of <NUM> to <NUM>, and more preferably <NUM>. The distance h2 is preferably in a range of <NUM> to <NUM>, and more preferably <NUM>. As can be seen from the above descriptions, to rotate the closure clamping portion <NUM> by the angle of α2, the actuator needs to drive the closure member matching portion <NUM> to move relative to the slot driving member <NUM> by a distance of h2-h1. When the angle α2 is <NUM>°, h1 is <NUM>, and h2 is <NUM>, namely the two closure clamping portions <NUM> are opened relatively at <NUM>°, the closure member matching portion <NUM> moves by a distance of <NUM>. With the cooperation of the first curved slot region, the second linear slot region and the third curved slot region, the closure member has the faster change process during opening at the initial position and at the position with the maximum opening angle compared with the intermediate capturing process, and meanwhile has a relative slow angular change at the capturing process, such that the capture is more stable. Compared with a common linear slot, the clamp mechanism <NUM> may achieve a shorter driving distance to reach a preset capturing angle. Moreover, at a position to perform fine operation, the clamp mechanism of the present closure may be safer and more reliable than that with a curved slot.

<FIG> illustrates an implementation of the guide slot <NUM> according to another embodiment of the present disclosure. The guide slot is divided into a first slot region and a second slot region from a distal end to a proximal end of the guide slot. As shown, the slot region is an arc segment, and the second slot region is a linear segment. This example is mainly intended to facilitate quick closure from the capturing position to the position with the maximum opening angle. In the tissue capturing process, the angular changing rate is reduced at the capturing segment by the linear segment, such that the capture is more stable. Specifically, from the most proximal end of the guide slot <NUM> to an intersection between the first slot region and the second slot region, the slot driving member may traverse along a varying angle of θ1, namely the slot driving member <NUM> may traverse the varying angle of θ1 in the linear slot region of the guide slot <NUM>. With a further movement to the most distal end, the single closure clamping portion <NUM> has an opening angle of θ2. Preferably, the angle θ1 is in a range of <NUM>° to <NUM>°, and the angle θ2 is in a range of <NUM>° to <NUM>°.

Referring to <FIG> and <FIG>, the drive assembly <NUM> includes a movable seat <NUM>. The movable seat <NUM> specifically includes a drive connecting member <NUM>. Side surfaces of the drive connecting member <NUM> include first mounting surfaces and second mounting surfaces perpendicular to each other. The drive connecting member <NUM> is hinged to the closure connecting portion <NUM> through the closure member matching portion <NUM> on the first mounting surfaces. This allows a movement of the closure member matching portion <NUM>, and further allows a relative movement between each guide slot <NUM> and slot driving member <NUM>.

Further, referring to <FIG>, each one of the capture members <NUM> of the disclosure includes a rigid capturing portion <NUM>, a flexible connecting portion <NUM>, and a capture connecting portion <NUM> that are connected sequentially. The flexible connecting portion <NUM> is located between the rigid capturing portion <NUM> and the capture connecting portion <NUM>. The second mounting surfaces are fixedly connected to the capture connecting portion <NUM>.

In the example, the capture member can cooperate with the closure member to capture a moving valve leaflet. A captured valve leaflet may be located between the closure member and the capture member. The capture connecting portion may be connected to the second mounting surfaces. The capture member is presented as spreading wings of a bird in a natural state. The flexible connecting portion is specifically a deformable component with a certain resilience force. By applying an external turning force to the rigid capturing portion, the flexible connecting portion elastically deforms to change an angle between the rigid capturing portion and an axial direction, thereby achieving turning of the capture member. When a moving valve leaflet to be captured is located above the closure member at a same side with the capture member, the elastic flexible connecting portion may be instantaneously restored to an initial shape in a natural state once the external turning force is removed. In such a case, the valve leaflet can be captured between the closure member and the rigid capturing portion. In the valve capture process, the rigid capturing portion is mainly used to fix the moving valve leaflet. The structure of the rigid capturing portion needs to have a certain rigidity, so as to prevent the captured valve leaflet from escaping from the capture member.

More preferably, the rigid capturing portion <NUM> includes a rigid surface <NUM>, and capturing barbules <NUM> provided outside the rigid surface. The rigid surface <NUM> has uniformly thick and is bent.

The rigid surface <NUM> has a rigid section, which is curved as shown in <FIG> or bent as shown in <FIG>. In the structure, the bent or curved portion is similar to a reinforcing rib formed on a main body. Consequently, the sheet-like thin-wall section has a high flexural coefficient and the rigidity of the rigid capturing portion is improved, without need of an additional component for reinforcing the rigidity. Moreover, in the example, when pushing and pulling the manipulation wire in the delivery control assembly, the manipulation wire applies a force to the capture member where the guide wire orifice <NUM> is located, thereby achieving turning of the capture member.

In the example, the two capture members <NUM> share one capture connecting portion <NUM>. The capture connecting portion <NUM> is U-shaped, with symmetrical vertical portions being respectively and fixedly connected to the second symmetrical mounting surfaces of the drive connecting member <NUM>. The capture connecting portion <NUM> may be fixedly connected to the drive connecting member <NUM> by hinging, riveting or welding, such that the capture member <NUM> may move axially with the drive connecting member <NUM>.

Take the slot driving members <NUM> as a reference point. When the drive connecting member <NUM> axially moves close to the slot driving member <NUM>, the closure member <NUM> is opened and turned, and the overall capture member <NUM> also axially moves close to the slot driving member <NUM>. If an external turning force toward the slot driving member <NUM> is applied to the rigid capturing portion of the capture member <NUM> at the same time, the capture member <NUM> is turned toward the slot driving member <NUM>. When a suitable valve leaflet contacts the opened closure member <NUM>, the external turning force applied on the capture member <NUM> can be removed, and the valve leaflet can be clamped between the closure member <NUM> and the capture member <NUM>.

In an embodiment, the capture member <NUM> is expanded in the natural state. The manipulation wire <NUM> is arranged to constrict the capture member <NUM> to an unexpanded state. By removing a constraint force of the manipulation wire <NUM>, the capture member <NUM> can be turned. In another embodiment, the capture member <NUM> may also be a flexible member, and may be directly turned under pushing of the manipulation wire <NUM> for capture.

Further, when the drive connecting member <NUM> starts to move axially away from the slot driving member <NUM>, the closure member <NUM> performs closing and turning movement together with the captured valve leaflet and the opened capture member <NUM>. Meanwhile, the drive connecting member <NUM> also moves axially away from the slot driving member <NUM> together with the capture member <NUM>. In this case, the capture member <NUM> and the valve leaflet have or trend to have a relative displacement. A pressure arising from an elastic deformation of the capture member <NUM> is applied to the valve leaflet. As a consequence, a friction force occurs on a contact surface between the capture member <NUM> and the valve leaflet that have the relative displacement. A direction that the capture member <NUM> applies the friction force to the valve leaflet refers to a direction toward the drive connecting member <NUM>, such that the capture member "pulls" the valve leaflet. By increasing a friction force or barbs features, such as the capturing barbs <NUM> in the embodiment, on the rigid capturing portion of the capture member <NUM>, the valve leaflet "pulling" effect will be more evident. Compared with the proximal element that is merely turned in the background art, the present disclosure may provide a connection between the valve leaflet and the fixing device more firm.

Further, referring to <FIG>, the closure clamping portion <NUM> in the embodiment includes a free end and a connecting end connected to the closure connecting portion <NUM>. In a direction from the connecting end to the free end, an outer surface of the closure clamping portion <NUM> at least partially tends to shrink toward an inner side. Due to the closure clamping portion <NUM> having a concave shape with a recess, a contact area with the valve leaflet can be increased when the valve leaflet is clamped. When the closure clamping portion clamps the valve leaflet in cooperation with the capture member <NUM>, the valve leaflet clamped in the recess of the closure clamping portion <NUM> can limit a radial displacement of the fixing device on the valve leaflet. With a flange, a damage of an edge of the closure clamping portion <NUM> to the valve leaflet can be prevented. After the valve leaflet is closed by the fixing device, due to the concave bend of the closure clamping portion <NUM>, end portions at two sides of the closure clamping portion are formed into a receiving portion, which makes the valve leaflet to be clamped more firmly in an axial direction. In addition, the clamp mechanism <NUM> in other embodiments of the present disclosure can also be arranged to relieve or treat "tricuspid regurgitation". That is, in addition to the original pair of closure members <NUM> and the original pair of capture members <NUM>, one more additional closure member and additional capture member are added to treat the "tricuspid regurgitation". The principle and structure for treating the tricuspid regurgitation are the same as those for treating the mitral regurgitation, and will not be repeated herein. It can be understood that other embodiments of the present disclosure can be apply to clamp several sheet-like tissues in other minimally invasive surgeries in other, and a number of the closure members <NUM> and a number of the capture members <NUM> are determined according to an actual use requirement.

In the embodiment, the clutch mechanism <NUM> includes an actuator rod <NUM> connected to the drive assembly <NUM> in a non-rotatable and axially separable manner. By rotating the actuator rod <NUM>, the drive assembly <NUM> is driven to move axially. The actuator rod <NUM> is arranged to be preset to drive the clutch mechanism <NUM> to disengage from the fixing device when the actuator rod is moved proximally. Following descriptions are made to a separation principle between the clutch mechanism <NUM> and the support mechanism <NUM> in combination with <FIG>, <FIG> and <FIG>.

The support mechanism <NUM> for carrying the clamp mechanism <NUM> includes a fixed connecting assembly <NUM> and a drive assembly <NUM> moveable relative to the fixed connecting assembly <NUM>. Specifically, the drive assembly <NUM> includes a push shaft <NUM>. The push shaft <NUM> includes a push shaft threaded portion <NUM> in cooperation with a base threaded portion <NUM>. The push shaft <NUM> may be directed axially by rotary movement between a drive output push shaft <NUM> and a base housing. The drive output push shaft <NUM> is rotated by applying a rotating torque to the actuator rod <NUM> in the clutch mechanism <NUM>. Specifically, the actuator rod includes an actuator rod clutching end <NUM> connected to the drive assembly <NUM> in an axially separable and non-rotatable manner, and an actuator rod supporting portion <NUM>. Specifically, the drive assembly <NUM> includes a transmission rod clutching end <NUM>. The actuator rod clutching end <NUM> is non-rotatably connected to the transmission rod clutching end <NUM>. When a tensile force between the actuator rod clutching end <NUM> and the transmission rod clutching end <NUM> is greater than a preset value, the actuator rod clutching end <NUM> is disengaged from the transmission rod clutching end <NUM>. Since a lead angle of a spiral annular groove is less than a friction angle of a contact surface between two spiral grooves, when the base housing or the drive shaft <NUM> is stopped, no axial displacement will occur if an axial force is only applied to the base housing or the drive shaft <NUM>. Therefore, in order to disengage the actuator rod clutching end <NUM> from the transmission rod clutching end <NUM>, the actuator rod <NUM> may simply be directed proximally relative to the transmission rod grasping end <NUM>, thereby implementing disengagement from the drive assembly <NUM> when the preset value is reached.

Specifically, an implementation for the disengagement of the fixing device from the drive assembly <NUM> when the preset value is reached is as follows.

One of the actuator rod clutching end <NUM> and the transmission rod clutching end <NUM> is provided with a deformable buckle <NUM>, while the other one of the actuator rod clutching end and the transmission rod clutching end is provided with a connecting groove <NUM>. The deformable buckle <NUM> may be made of an elastic biocompatible material, such as a biocompatible high polymer material. The engagement shaft <NUM> which can be cooperatively connected to the deformable buckle <NUM> is provided in the connecting groove <NUM>. The engagement shaft <NUM> is inserted into an engagement shaft hole <NUM>. Specifically, the deformable buckle <NUM> is provided with a bayonet <NUM> and a clamping hole <NUM> matched with the engagement shaft <NUM> through the bayonet <NUM>. The actuator rod clutching end <NUM> and the transmission rod clutching end <NUM> are connected to the engagement shaft <NUM> through the deformable buckle <NUM>. When the tensile force between the actuator rod clutching end <NUM> and the transmission rod clutching end <NUM> is greater than a preset value, the deformable buckle <NUM> is disengaged from the engagement shaft <NUM>. In the embodiment, the deformable buckle <NUM> is provided at the actuator rod clutching end <NUM>, while the connecting groove <NUM> is provided at the transmission rod clutching end <NUM>. However, an opposite arrangement is also conceivable.

In order to ensure an outer housing of the support mechanism <NUM> is separated from an outer housing of the clutch mechanism <NUM> when the actuator rod clutching end <NUM> is separated from the transmission rod clutching end <NUM>, specifically, the clutch mechanism <NUM> in the embodiment is further provided with a coupling seat <NUM> separably connected to the base clutching end <NUM>, and an engagement member <NUM> for connecting the base clutching end <NUM> and the coupling seat <NUM>. The actuator rod <NUM> is arranged to be moveable relative to the engagement member <NUM> between a first position and a second position. When the actuator rod <NUM> moves toward the proximal end from the second position, an actuator rod supporting portion <NUM> can drive the engagement member <NUM> to move toward the proximal end as well, such that the coupling seat <NUM> can be relatively separated from the base clutching end <NUM>. Therefore, when the actuator rod clutching end <NUM> is separated from the transmission rod clutching end <NUM>, the coupling seat <NUM> can also be synchronously separated from the base clutching end <NUM>.

Specifically, the coupling seat <NUM> in the embodiment includes a coupling seat connecting end <NUM>, a coupling seat clutching end <NUM>, and a coupling seat inner cavity <NUM> defined through the coupling seat <NUM>. The engagement member <NUM> is provided in the coupling seat inner cavity <NUM>. The coupling seat clutching end <NUM> is connected to the base clutching end <NUM> via the engagement member <NUM>. The coupling seat connecting end <NUM> is connected to a delivery device.

A main body of the base clutching end <NUM> is an extension of a tubular base structure. The coupling seat clutching end <NUM> can be sleeved on the base clutching end <NUM>, or inserted into the base clutching end <NUM>. Contact surfaces of the two ends are respectively referred to as a base matching surface and a coupling seat matching surface. A base clamping hole <NUM> is formed on the base matching surface in a radial direction. Correspondingly, a coupling seat clamping hole <NUM> having a same orientation is formed on the coupling seat matching surface in a radial direction. The coupling seat clutching end <NUM> is provided with the coupling seat clamping hole <NUM>. The base clutching end <NUM> is provided with the base clamping hole <NUM> corresponding to the coupling seat clamping hole <NUM>. The engagement member <NUM> includes buckles <NUM>, each of which pass through both the coupling seat clamping hole <NUM> and the base clamping hole <NUM>, such that the coupling seat <NUM> and the base clutching end <NUM> are fixed relatively to one another. The buckle <NUM> is arranged in such a manner that, when the engagement member <NUM> moves toward the proximal end relative to the coupling seat <NUM>, the buckle <NUM> gets away from the coupling seat clamping hole <NUM> and/or the base clamping hole <NUM>, such that the coupling seat <NUM> and the base clutching end <NUM> can be separated from each other.

The buckle <NUM> is made of a flexible material. When the engagement member <NUM> moves toward the proximal end relative to the coupling seat <NUM>, the buckle <NUM> deforms such that it can directly exit the coupling seat clamping hole <NUM> and the base clamping hole <NUM>, without resilience to cause failure of the separation. The buckle <NUM> is made of a biocompatible plastic or metal material that is not resilient after being bent.

Further, the engagement member <NUM> in the embodiment further includes one claw bottom ring <NUM> and claw connecting rods <NUM>. The number of the claw connecting rods <NUM> is the same as the buckles <NUM>, and the claw connecting rods <NUM> connect the buckles <NUM> to the claw bottom ring <NUM>, respectively. The claw bottom ring <NUM> is provided with a bottom ring opening. There may be three to six claw connecting rods <NUM> that are uniformly connected to a side of the claw bottom ring <NUM>. Preferably, there are three claw connecting rods <NUM>. A movement of the buckle <NUM> to a center is obstructed by a radial surface of the push shaft-like or rod-like joystick supporting portion <NUM>. It can prevent the buckle <NUM> from accidentally separating from the base clamping hole <NUM> and the coupling seat clamping hole <NUM>, and ensure the connection between the base clutching end <NUM> and the coupling seat <NUM>.

The actuator rod <NUM> further includes an actuator rod connecting end <NUM> connected to a proximal end of the actuator rod supporting portion <NUM>. A proximal end of the actuator rod connecting end <NUM> is connected to a drive source through the bottom ring opening. An outer diameter of the proximal end of the actuator rod supporting portion <NUM> is greater than an inner diameter of the bottom ring opening.

The actuator rod supporting portion <NUM> is shorter than each of the claw connecting rods <NUM>. An outer diameter of the actuator rod supporting portion <NUM> is provided in such a manner that, when the actuator rod supporting portion <NUM> is located in the coupling seat clamping hole <NUM>, an outer surface of the actuator rod supporting portion <NUM> prevents the buckle <NUM> from getting away from the coupling seat clamping hole <NUM> and the base clamping hole <NUM>. Hence, the buckle <NUM> deforms only when the actuator rod supporting portion <NUM> contacts the claw bottom ring <NUM> and further moves toward the proximal end.

On the basis of the above structure, to separate the base clutching end <NUM> from the coupling seat <NUM>, the actuator rod <NUM> needs to move toward the claw bottom ring <NUM> under an axial force. When the claw bottom ring <NUM> is squeezed by the actuator rod, the actuator rod supporting portion <NUM> is disengaged from the buckle <NUM> and no longer limits a radial movement of the buckle <NUM>. Under a condition of a sufficient external force, the buckle <NUM> can be pulled out from the base clamping hole <NUM> and the coupling seat clamping hole <NUM>, to achieve separation of the base clutching end <NUM> from the coupling seat <NUM>.

The above example is further described below. The coupling seat clutching end <NUM> is sleeved on the base clutching end <NUM>. As shown in <FIG>, the coupling seat <NUM> includes a manipulation wire limiting groove <NUM>. The manipulation wire <NUM> for controlling the capture members <NUM> of the clamp mechanism <NUM> to open and close in the delivery control assembly includes an expanded head end. The expanded head end is provided in a base clutching end hole <NUM>. The minimal size of the expanded head end is greater than the manipulation wire limiting groove <NUM> and less than the base clutching end hole <NUM>. When the coupling seat <NUM> is connected the base clutching end <NUM>, the separation of the manipulation wire <NUM> is limited through the manipulation wire limiting groove <NUM>.

In an embodiment, the actuator rod <NUM> is provided therein with a channel extending through the proximal end to a channel of the actuator rod clutching end <NUM>. The actuator rod <NUM> in this embodiment is internally hollow and is different from those solid ones for threaded connection in the prior art. Due to the cooperation between the connecting groove <NUM> and the deformable buckle <NUM>, and additionally a flexible push shaft for controlling a direction, an external operation structure for controlling turning can be omitted.

The structure and principle of the support mechanism <NUM> are described below in combination with <FIG> and <FIG>. The support mechanism <NUM> includes a fixed connecting assembly <NUM> and a drive assembly <NUM> moveable relative to the fixed connecting assembly <NUM>. A distal end of the drive assembly <NUM> is connected to two closure members <NUM>, so as to control the closure members <NUM> to open or close when the drive assembly <NUM> moves relative to the fixed connecting assembly <NUM>. Specifically, the closure members <NUM> of the clamp mechanism <NUM> each include a closure connecting portion <NUM> and include a closure clamping portion <NUM>. The closure clamping portions <NUM> serve to cooperate with the capture members <NUM> to clamp a tissue. The guide slots <NUM> are formed in the closure connecting portion <NUM>. A slot driving member <NUM> at least partially located in the nonlinear guide slot <NUM> is provided on the fixed connecting assembly <NUM>. The guide slot <NUM> includes at least a nonlinear segment. The drive assembly <NUM> is connected to the two closure clamping portions <NUM>, and is arranged to allow the slot driving member <NUM> to slide within the guide slot <NUM> when the drive assembly <NUM> moves relative to the fixed connecting assembly <NUM>, thereby driving the two closure clamping portions <NUM> to relatively move close to or away from each other.

Further, the base housing is further provided with a base lug <NUM> at the distal end. The slot driving member <NUM> is disposed outside the base lug <NUM>. By controlling the drive assembly <NUM> to move relative to the slot driving member <NUM>, the closure member <NUM> is opened or closed.

Specifically, the fixed connecting assembly <NUM> includes a base housing. A base inner cavity <NUM> is formed in the base housing. A base threaded portion <NUM> is provided in the base inner cavity <NUM>. The drive assembly <NUM> includes a push shaft <NUM>. The push shaft <NUM> includes a push shaft threaded portion <NUM> in cooperation with the base threaded portion <NUM>. A lead angle at which the base threaded portion <NUM> is cooperated with the push shaft threaded portion <NUM> is less than a friction angle.

In the example, the push shaft threaded portion <NUM> and the base threaded portion <NUM> slidably cooperate with each other. They have a same thread pitch and a same sectional shape. By rotating either the base housing or the push shaft <NUM>, the base housing and the push shaft <NUM> can move axially relative to each other. Since a lead angle of a spiral annular groove is less than a friction angle of a contact surface between the two spiral grooves, no axial displacement would occur when the base housing or the push shaft <NUM> is stopped, if only an axial force is applied to the base housing or the push shaft <NUM>. Therefore, a self-locking function can be achieved without using a spring piece or other structures, unlike in the prior art, and can hold its position through a thread fit.

The drive assembly <NUM> further includes a drive output push shaft <NUM> disposed at a distal end of the drive shaft <NUM> and having an outer diameter less than that of the drive shaft <NUM>. The drive connecting member <NUM> is provided with a connection guide hole <NUM> having an inner diameter matched with the drive output push shaft <NUM>. The drive output push shaft <NUM> is axially and rotatably cooperated with the connection guide hole <NUM>. The drive assembly <NUM> further includes a locating sleeve <NUM> disposed at a distal end of the drive connecting member <NUM>. The drive output push shaft <NUM> extends to a locating sleeve mounting hole <NUM> of the locating sleeve <NUM> through the connection guide hole <NUM>, and fixedly connected to the locating sleeve <NUM>.

As can be seen from the above structural descriptions, how the drive output push shaft <NUM> is movably cooperated with the drive connecting member <NUM> is disclosed in the embodiment. An output end of the drive output push shaft <NUM> outputs thrust force and tensile force to the drive connecting member <NUM>, achieve axial movement of the drive connecting member <NUM>. However, as the drive output push shaft <NUM> and the base housing are rotatably moved relative to each other while the drive connecting member <NUM> and the base housing are not, the above structure can realize a rotary driving process without causing any rotation movement of the clamp mechanism to rotate, and the clamp mechanism can move stably in the axial direction. The locating sleeve <NUM> may be a tubular part. End surfaces of the locating sleeve <NUM> are axial end surfaces at two sides. The locating sleeve <NUM> and the output end of the drive output push shaft <NUM> may be fixedly connected by either welding or interference fit, or mechanical connection. For example, the mechanical connection may be as follows. A locating sleeve positioning hole <NUM> may be formed on the locating sleeve <NUM> in a radial direction. A drive output push shaft positioning hole <NUM> is formed, in a radial direction, on the output end of the drive output push shaft <NUM> at the position where the output end of the drive output push shaft <NUM> is cooperated with the locating sleeve <NUM>. Pins <NUM> are respectively provided in each of the locating sleeve positioning hole <NUM> and the drive output push shaft positioning hole <NUM>.

The clamp mechanism <NUM> is described in the embodiment further referring to <FIG> and <FIG>. Specifically, a distal end of the closure connecting portion <NUM> is rotatably connected to the drive assembly <NUM>, in particular to a distal end of the drive assembly <NUM>. In the embodiment, the closure connecting portion <NUM> is provided with a connecting portion push shaft hole <NUM>, and is connected to the drive assembly <NUM> through a rotating push shaft. In other embodiments, other hinged methods may be conceivable. Before the fixing device is delivered to the target location, the closure clamping portion <NUM> is in an initial state in which the slot driving member <NUM> is located at the proximal end of the guide slot <NUM>, and the closure clamping portion <NUM> is closed, as shown in <FIG>. Under driving of the drive assembly <NUM>, when the rotating joint between the drive assembly <NUM> and the closure connecting portion <NUM> moves toward the proximal end, i.e., the connecting portion push shaft hole <NUM> moves toward the proximal end, the guide slot <NUM> moves toward the proximal end synchronously due to the cooperation between the slot driving member <NUM> and the guide slot <NUM>. In such a case, the slot driving member <NUM>, which is not moved, actually moves toward the distal end relative to the guide slot <NUM>. In order to make the closure clamping portion <NUM> adapt to the change of distance, the slot driving member <NUM> rotates the guide slot <NUM> in some extent relative to the connecting portion push shaft hole <NUM>, such that the closure clamping portion <NUM> is rotated with the connecting portion push shaft hole <NUM> as a center. In such a case, the closure clamping portion <NUM> is turned outward with the connecting portion push shaft hole <NUM> as an axial center, to enter the states as shown in <FIG>. By further driving the connecting portion push shaft hole <NUM> to move toward the proximal end, the closure clamping portion <NUM> can enter a state, in which the two closure clamping portions <NUM> form an angle of <NUM>° relative to each other, and the distance between the end portions achieves a maximum capturing distance, as shown in <FIG>.

Due to the design of the guide slots <NUM>, the two closure clamping portions <NUM> may be turned to form an angle of <NUM>°, and further an obtuse angle as shown in <FIG>. It can be applied when the fixing device needs to be withdrawn from the heart in case of inaccurate location or other problems. During the moving-out process, the two closure clamping portions <NUM>, which form an obtuse angle, tend to incline outward relative to the contact surfaces with the tissue and would not hook the tissue. Hence, the withdrawal can be smooth and safe. The specific principle of the process in which the closure clamping portion <NUM> is cooperated with the guide slot <NUM> through the slot driving member <NUM> to achieve the above opening angle will be described below in detail.

In the embodiment, throughout the opening and closing processes of the closure clamping portion <NUM>, the drive assembly <NUM> moves relative to the slot driving member <NUM>, while the slot driving member <NUM> does not move relative to the fixed connecting assembly <NUM> connected therewith. Hence, during the process in which the closure clamping portion <NUM> of the closure member <NUM> is moved from an initial state to an open state, the closure connecting portion <NUM> at the distal end moves toward the proximal end. Compared with the prior art where the clamping element is only opened and turned, the closure member <NUM> in the present disclosure involves two kinds of movement in combination to allow the closure member <NUM> to achieve a wider opening distance in the radial direction. Further, in the initial state of the closure clamping portion <NUM>, the closure connecting portion <NUM> is not provided with other additional mechanisms. In such a case, a height of the overall fixing device can be lowered, and it is more convenient to turn during delivery. In view of this, the closure member <NUM> can also be longer to facilitate a greater capturing distance.

After the closure clamping portion <NUM> is cooperated with the capture member <NUM> to clamp the tissue, the closure clamping portion <NUM> further needs to be folded. When the closure clamping portion <NUM> is folded, the closure connecting portion <NUM> moves toward the distal end, and thus the closure clamping portion <NUM> has an effect of being pulled toward the distal end. In such a case, a characteristic of "grabbing" movement may present in the folding process. When the tissue is clamped firmly, the valve leaflet on the closure clamping portion <NUM> may be "pulled" in some extent, facilitating a more firm contact between the valve leaflet and the closure clamping portion <NUM>.

In order to illustrate a specific application of the device in the embodiment in surgery, an operation method of a system for clamping a tissue according to the disclosure is described in combination with specific structures in the embodiment, taking mitral valve repair as an example.

First step: pushing the fixing device connected to the push shaft <NUM>, from a left atrium to a left ventricle through the mitral valve by the push shaft <NUM>. In this case, the closure members <NUM> of the clamp mechanism <NUM> are in a closed state, as shown in <FIG>.

Second step: adjusting relative positions of the valve fixing device and the mitral valve by the push shaft <NUM>, such that the two closure members <NUM> of the fixing device are respectively close to the anterior valve leaflet and the posterior valve leaflet of the mitral valve. Then, rotating the push shaft <NUM>. The base threaded portion <NUM> is cooperated with the drive threaded portion <NUM> to drive the drive connecting member <NUM> to move toward the distal end. Taking the slot driving member <NUM> as a reference point, when the drive connecting member <NUM> axially moves close to the slot driving member <NUM>, the closure members <NUM> are opened and turned to enter the states as shown in <FIG>. The closure members may also be further turned to enter the state as shown in <FIG>. In this case, the distance between the end portions of the two closure members <NUM> is maximized. After the two closure clamping portions <NUM> form an angle of <NUM>°, they may further be turned to form an obtuse angle as shown in <FIG>, which can be applied when the fixing device needs to be withdrawn from the heart in case of inaccurate location or other problems. During the moving-out process, the two closure clamping portions <NUM>, which form an obtuse angle, tend to incline outward relative to the contact surfaces with the tissue and would not hook the tissue. Hence, the withdrawal can be smooth and safe.

Third step: After a valve leaflet is captured by the two closure members <NUM>, the capture member <NUM> is turned toward the closure clamping portion <NUM> by the manipulation wire <NUM>, and thus the valve leaflet can be clamped between the closure member <NUM> and the capture member <NUM>, as shown in <FIG>.

Fourth step: When the drive connecting member <NUM> starts to move axially away from the slot driving member <NUM>, the closure member <NUM> is closed and turned together with the captured valve leaflet and the opened capture member <NUM>. Meanwhile, the drive connecting member <NUM> moves axially away from the slot driving member <NUM> together with the capture member <NUM> to enter the states as shown in <FIG>. In this case, the capture member <NUM> and the valve leaflet have a relative displacement or trend to have a relative displacement. A pressure arising from an elastic deformation of the capture member <NUM> is applied to the valve leaflet. As a consequence, a friction force occurs on a contact surface between the capture member <NUM> and the valve leaflet that have the relative displacement. The capture member <NUM> applies the friction force to the valve leaflet in a direction towards the drive connecting member <NUM>, such that the capture member "pulls" the valve leaflet.

When the system for clamping a tissue according to the present disclosure is applied to repair the heart valve, the closure clamping portion has an effect of being pulled to the distal end, and a "grabbing" movement may occur in the folding process. When the tissue is clamped firmly, the valve leaflet on the closure clamping portion is "pulled". By employing the guide slot having the nonlinear segment for assisting driving, and increasing the opening angle and the capturing distance of the closure member, the fixing device makes it easy to capture the valve leaflet, increase the contact with the valve leaflet, and makes the valve leaflet to be captured more firmly.

Apparently, the terms such as "front", "rear", "upper", and "lower" as used in the description, refer to position and orientation relationships of parts and components in accordance with drawings for convenience of description for the purpose of simplicity and convenience. It should be understood that such orientation terms are not intended to limit the protection scope claimed by the present disclosure.

Claim 1:
A heart valve clamp device, comprising:
a fixing device comprising a clamp mechanism (<NUM>) for closing a heart valve, and a support mechanism (<NUM>) carrying the clamp mechanism (<NUM>), the support mechanism (<NUM>) comprising a drive assembly (<NUM>) for driving the clamp mechanism (<NUM>) to open and close; and
a delivery control device comprising a push shaft (<NUM>) for introducing the fixing device to a target location and a clutch mechanism (<NUM>) for enabling the push shaft (<NUM>) and the fixing device to be separably connected; wherein
the clamp mechanism (<NUM>) comprises a pair of closure members (<NUM>) each provided with a guide slot (<NUM>) comprising at least a nonlinear segment, the support mechanism (<NUM>) comprising slot driving members (<NUM>), each of which is at least partially located in the guide slots (<NUM>) and is slidable in the guide slots (<NUM>), so as to drive two closure clamping portions (<NUM>) to move towards or away from each other.