CN111938869A - Tissue holder and valve clamping device - Google Patents

Abstract

The invention discloses a tissue clamping piece which comprises a connecting frame and two clamping arms, wherein the connecting frame comprises two connecting sheets which are opposite at intervals; the two clamping arms are respectively arranged on the opposite side edges of the two connecting sheets, each clamping arm extends to one side far away from the other clamping arm, each clamping arm comprises a bending section connected to the corresponding connecting sheet and a clamping section connected to the bending section far away from the corresponding connecting sheet, and the width of the bending section is smaller than that of the clamping section and smaller than that of the connecting sheet; the valve clamping device has the advantages that the weight of the valve clamping device can be reduced, the pulling force required for pulling the two clamping arms of the valve clamping device to the fit central shaft through the control wires can be reduced, the reverse acting force born by the control wires is reduced, the control wires are prevented from being broken, and the operation is facilitated. The invention also provides a valve clamping device provided with the tissue clamping piece.

Description

Tissue holder and valve clamping device

technical field

The invention relates to the field of interventional medical instruments, in particular to a tissue clamping piece and a valve clamping device provided with the tissue clamping piece.

Background technique

Please refer to Figure 1, the mitral valve 1 is a one-way valve located between the left atrium 2 and the left ventricle 3 of the heart. A normal healthy mitral valve 1 can control the flow of blood from the left atrium 2 to the left ventricle 3, while preventing blood from flowing from the left atrium 2 to the left ventricle 3. Left ventricle 3 flows into left atrium 2. The mitral valve 1 includes a pair of leaflets, referred to as an anterior leaflet 1a and a posterior leaflet 1b. The anterior lobe 1a and the posterior lobe 1b are fixed to the papillary muscle of the left ventricle 3 through the chordae tendineae 4 . Under normal circumstances, when the left ventricle 3 of the heart contracts, the edges of the anterior lobe 1a and the posterior lobe 1b are completely aligned, preventing blood from flowing from the left ventricle 3 to the left atrium 2. Please refer to Fig. 2, when the leaflets of mitral valve 1 or their related structures change qualitatively or functionally, such as partial rupture of chordae tendineae 4, the anterior leaflet 1a and posterior leaflet 1b of mitral valve 1 are misaligned , thus, when the left ventricle 3 of the heart contracts, the mitral valve 1 cannot be completely closed, causing the blood to flow back from the left ventricle 3 to the left atrium 2, thereby causing a pathophysiological change in the primary system, known as "mitral regurgitation" flow".

Surgical procedures such as edge-to-edge suturing are usually used to treat mitral regurgitation. However, this type of surgery has disadvantages such as complex surgical procedure, high surgical cost, high degree of patient trauma, high risk of complications, long hospital stay, and painful recovery process for patients. There is a minimally invasive treatment operation, which is based on the principle of edge-to-edge operation of the valve. The valve clamping device is delivered to the mitral valve through an interventional catheter, and then the anterior and posterior leaflets of the mitral valve are clamped at the same time, so that the valve is clamped. The leaves are drawn closer to each other, alleviating "mitral regurgitation". The valve clamping device uses a pair of concave jaw arms and a tissue holder made of shape memory material to cooperate with each other to fix the leaflet of the mitral valve between the jaw arms and the tissue holder. That is, the forceps arm and the tissue holding member simultaneously grasp the anterior leaflet and the posterior leaflet of the mitral valve, so as to achieve the purpose of fixing the valve leaflet and reducing mitral valve regurgitation.

Specifically, when the valve clamping device is in the delivery state, the tissue clamping member is pulled by the slender control wire and then attached to both sides of the central axis of the valve clamping device, and is delivered to the mitral valve through the slender delivery catheter Then adjust the position of the valve clamping device, after releasing the pulling of the control wire on the tissue clamping member, the tissue clamping member expands due to its own shape memory property and presses the valve leaflet into the forceps arm, thereby matching with the forceps arm. The clamp arms cooperate to hold the valve leaflets. Please refer to FIG. 3 , the tissue clamping member 3a includes a base 3a1 and clamping arms 3a2 disposed on opposite sides of the base 3a1. Each clamping arm 3a2 is provided with an opening 3a3 to reduce the stress at the position and reduce the Small pulling force increases the resilience; however, this clamping arm 3a2 reduces its own fatigue resistance; if the clamping arm 3a2 does not have an opening 3a3, the clamping arm 3a2 is pulled up to fit the valve The central axis of the clamping device requires a large pulling force, and has high requirements on the control wire and the proximal handle, which may easily lead to the breakage of the control wire.

SUMMARY OF THE INVENTION

In view of this, the present invention provides a tissue clamping member and a valve clamping device, which can not only improve the fatigue resistance of the tissue clamping member, but also reduce the stress when the tissue clamping member is in a folded state, so as to reduce the amount of tissue clamping. The tension required to pull the piece up to the tucked state prevents the control wire from breaking.

In order to solve the above technical problems, the present invention provides a tissue clamp, which includes a connection frame and two clamp arms, the connection frame includes two spaced opposite connection pieces; the two clamp arms are respectively arranged in the On the opposite sides of the two connecting pieces, each of the clamping arms extends to a side away from the other clamping arm, and each clamping arm includes a bending section connected to the corresponding connecting piece and a bending section connected to the corresponding connecting piece. The bending section is far away from the clamping section of the corresponding connecting piece, and the width of the bending section is smaller than the width of the clamping section and smaller than the width of the connecting piece.

The present invention also provides a valve clamping device, which includes a fixing seat, a pair of forceps arms that are open and closed relative to the fixing seat, and a tissue clamping member, wherein the tissue clamping member is arranged on the fixing seat Between the clamp arms, the two clamp arms of the tissue clamp are respectively matched with one of the pair of clamp arms to clamp the valve leaflets.

Each clamping arm of the valve clamping device provided by the present invention has a bending section, and the width of the bending section is smaller than the width of the clamping section and smaller than the width of the connecting piece; thus not only can reduce the weight of the valve clamping device, but also It is beneficial to the rebound of the gripping arm, reducing the difficulty of gripping, improving the fatigue resistance of the tissue gripper, and reducing the tension required to pull the gripping arm up to fit the central axis through the control wire, reducing the burden on the control wire. The reverse force can prevent the control wire from breaking, improve the fatigue resistance of the valve clamping device implanted in the human body for a long time, and improve the safety and effectiveness of the device.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the implementation manner. As far as technical personnel are concerned, other drawings can also be obtained based on these drawings without any creative effort.

Figure 1 is a schematic view of the mitral valve in a normal state.

Fig. 2 is a schematic diagram of the mitral valve with lesions.

Fig. 3 is a schematic three-dimensional structural diagram of a tissue holder in the prior art.

FIG. 4 is a schematic three-dimensional structural diagram of a valve clamping device provided in one embodiment of the present invention.

FIG. 5 is a schematic three-dimensional structural diagram of the tissue clamping member and the fixing seat of the valve clamping device in FIG. 4 .

FIG. 6 is an exploded schematic diagram of the three-dimensional structure of the tissue holder and the fixing base in FIG. 5 .

FIG. 7 is a side view of the tissue gripper of FIG. 6 .

FIG. 8 is a top view of the tissue gripper of FIG. 6 .

FIG. 9 is a schematic structural diagram of another embodiment of the tissue holder in FIG. 7 .

FIG. 10 is a side view of the tissue gripper and mount of FIG. 5 .

FIG. 11 is an enlarged view of part XI in FIG. 10 .

FIG. 12 is a side view of the valve clamping device of FIG. 4 .

FIG. 13 is a diagram of one of the states of use of the valve clamping device in FIG. 4 .

FIG. 14 is a schematic structural diagram of a valve clamping device provided by another embodiment of the present invention.

FIG. 15 is a schematic structural diagram of the clamping arm of the valve clamping device in FIG. 14 .

FIG. 16 is a statistical chart of the results of the fatigue test and the performance test of the tissue clamp for the valve clamping device of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Furthermore, the following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the invention may be practiced. Directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", "inside", "outside", "side", etc., only Reference is made to the directions of the accompanying drawings, therefore, the directional terms used are for better and clearer description and understanding of the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, in a specific orientation construction and operation, and therefore should not be construed as limiting the invention.

In the description of the present invention, it should be noted that in the field of interventional medical devices, the proximal end refers to the end closer to the operator, while the distal end refers to the end farther away from the operator; the axial direction refers to the end parallel to the natural The direction of the line connecting the center of the distal end and the center of the proximal end of the medical device in the state. The above definitions are only for the convenience of expression, and should not be construed as limiting the present invention.

Please refer to FIG. 4 to FIG. 6 together. The first embodiment of the present invention provides a valve clamping device 100 , which includes a fixing base 20 , at least a pair of clamp arms 40 hinged with the fixing base 20 , and a clamp arm 40 connected to the fixing base 20 . A tissue holding member 60 and a drive assembly 70 for driving the forceps arm 40 to open and close relative to the fixed seat 20; a pair of forceps arms 40 to open and close relative to the fixed seat 20, and the tissue holding member 60 is provided on the fixed seat 20 and the forceps arm Between 40 , in order to cooperate with the forceps arm 40 to hold the valve leaflet, the tissue holding member 60 includes a connecting frame 62 and two holding arms 64 . When in use, the proximal end of the valve clamping device 100 is releasably connected to the delivery device, and the two clamping arms 64 of the valve clamping device 100 are pulled up to the center axis of the abutment through the control wire, and the operator clamps the valve. The device 100 is pushed to the patient's mitral valve, and then the valve clamping device 100 is remotely operated, so that the clamp arm 40 is opened relative to the fixed seat 20, and then the pulling force of the control wire on the two clamping arms 64 is released, and the mitral valve is clamped. The anterior and posterior leaflets of the valve are respectively clamped by the clamp arms 40 and the corresponding clamping arms 64, so that the leaflets of the mitral valve are abutted together edge-to-edge, and then the delivery device is released and clamped with the valve The connection between the devices 100, the valve clamping device 100 remains in the patient as an implant in order to keep the coapted position of the valve leaflets together, achieve "edge-to-edge repair" of the mitral valve, relieve the patient's mitral Valve regurgitation.

It should be noted that, the valve clamping device 100 and the delivery device can be delivered to the patient's body by using an existing guide device such as an adjustable sheath tube, a plastic sheath tube, and the like.

Specifically, the connecting frame 62 includes a base plate 621 and two connecting pieces 623 disposed on opposite sides of the base plate 621; two clamping arms 64 are respectively disposed on the opposite sides of the two connecting pieces 623, A side extending away from the other clamping arm 64; each clamping arm 64 includes a bending section 641 connected to the corresponding connecting piece 623 and a clamping section 643 connected to the bending section 641 away from the corresponding connecting piece 623, The width of the bending section 641 is smaller than the width of the clamping section 643 and smaller than the width of the connecting piece 623; the two clamping arms 64 of the tissue clamping member 60 are respectively matched with one of the pair of clamp arms 40 to clamp the flap Leaflet 300 (shown in FIG. 13 ), ie, the gripping section 643 of each gripping arm 64 cooperates with one of the gripper arms 40 to grip a piece of leaflet 300 .

In the present invention, each clamping arm 64 of the valve clamping device 100 has a bending section 641, and the width of the bending section 641 is smaller than the width of the clamping section 643 and smaller than the width of the connecting piece 623; thus not only can reduce the valve The weight of the clamping device 100 is beneficial to the rebound of the clamping arm 64, reduces the difficulty of clamping, improves the fatigue resistance of the tissue clamping member 60, and can also reduce the pulling up of the clamping arm 64 to the center axis of the fit through the control wire The required pulling force reduces the reverse force borne by the control wire, prevents the control wire from breaking, can improve the fatigue resistance of the valve clamping device 100 implanted in the human body for a long time, and improve the safety and effectiveness of the device.

As shown in FIG. 4 , in this embodiment, the valve clamping device 100 includes a pair of clamp arms 40 disposed opposite to each other, and each clamp arm 40 can be opened and closed relative to the fixing seat 20 . Each clamp arm 40 includes a connection frame 42 and a clamping frame 44 connected to one end of the connection frame 42 away from the fixing base 20 . The ends of the connection frames 42 of the two clamp arms 40 away from the clamping frame 44 are stacked on each other and then hinged to the fixing base. 20. A leaflet accommodating space is formed between the clamping arm 64 and the forceps arm 40 . The surface of each clamp arm 40 facing the clamping arm 64 is recessed inwardly to form a receiving groove 45, so that in the delivery state of the valve clamping device 100, the clamping arm 64 is at least partially accommodated in the receiving groove 45 of the clamp arm 40, In order to reduce the outer diameter and volume of the valve clamping device 100, it is convenient for delivery in the body. After the clamp arm 40 cooperates with the clamp arm 64 to clamp the valve leaflet 300, the valve leaflet 300 is clamped in the receiving groove 45, which can increase the contact area between the clamp arm 40 and the valve leaflet 300, and enable the clamp arm 64 to hold the valve leaflet 300. The 300 is pressed into the receiving groove 45 of the forceps arm 40 to increase the clamping force of the valve leaflet 300 .

Specifically, each clamp arm 40 includes a rectangular connecting plate 442 and side plates 444 disposed on opposite sides of the connecting plate 442 . The connecting plate 442 and the two side plates 444 enclose a receiving groove 45 . The connecting plate 442 defines a number of material removal holes 446 along its length to reduce the weight of the clamp arm 40 . One end of the side plate 444 adjacent to the fixing base 20 extends obliquely and is hinged on the fixing base 20 to form a connecting portion 42 of the clamp arm 40 , and the connecting portion 42 defines a pin hole for inserting a pin.

The clamp arm 40 is opened and closed relative to the fixed seat 20 through the drive assembly 70 . The driving assembly 70 includes a driving shaft 72 passing through the fixing base 20 , a connecting base 74 disposed at the distal end of the driving shaft 72 , and a pair of connecting rods 76 movably connected to both sides of the connecting base 74 . One end of each link 76 is connected to a corresponding one of the clamp arms 40, and the other end is connected to the connection seat 74 by pivoting, that is, each clamp arm 40 is connected to the connection of the driving assembly 70 through the connecting rod 76 on the corresponding side. Seat 74 is distal. The drive shaft 72 movably passes through the fixing base 20 and is connected to the connecting base 74 . When the drive shaft 72 slides relative to the fixed seat 20 in the axial direction, the connecting seat 74 moves in the axial direction to rotate the connecting rod 76 and drive the clamp arm 40 to open and close relative to the fixed seat 20 .

As shown in FIG. 6 , the fixing base 20 includes a rectangular fixing frame 21 , a connecting block 22 arranged at the proximal end of the fixing frame 21 , and bosses 23 arranged on opposite sides of the fixing frame 21 , and the fixing base 20 is axially arranged. A through hole 24 is provided to penetrate through the connecting block 22 and the fixing frame 21 , and the through hole 24 is used for inserting the drive shaft 72 therethrough. The opposite ends of the connecting block 22 are respectively provided with pin holes 26 . The axis of the pin holes 26 is perpendicular to the axis line of the through hole 24 . The fixing frame 21 is respectively provided with a first attaching curved surface 212 and a second attaching curved surface 214 on opposite sides of the connecting block 22 , wherein the first attaching curved surface 212 is closer to the connecting block 22 than the second attaching curved surface 214 . The curvature radius of the attaching curved surface 212 is K1, and the curvature radius of the second attaching surface 214 is K2.

The tissue gripper 60 is at least partially made of a shape memory material and has undergone a heat setting process so that the tissue gripper 60 has a natural expanded state and a collapsed state. During production, the shape memory material is first cut into the desired shape by laser cutting, and then placed in a mold for heat setting at about 550°C to make it have a specific shape. As shown in FIG. 7 , in the natural state, the clamping arms 64 on both sides of the tissue clamping member 60 extend radially outward relative to the connecting frame 62; preferably, the clamping arms 64 extend obliquely toward the distal end so as to facilitate and The clamp arms 40 cooperate to clamp the valve tissue, that is, the angle between the clamping arms 64 on both sides in the natural unfolded state should be slightly larger than the angle between the two clamp arms 40 to provide more stable clamping Therefore, there is a certain clamping force between the clamping arm 64 and the clamping arm 40 to clamp the valve leaflet located therebetween; specifically, the length direction of the clamping section 643 of each clamping arm 64 The included angle a between the axial direction of the fixing seat 20 is greater than the included angle between the clamping arm 40 and the axial direction of the fixing seat 20 when the clamp arm 40 corresponding to the clamping arm 64 is fully opened with respect to the fixing seat 20, so that each The free end of a clamping arm 64 and the corresponding clamping arm 40 are close to each other and have a certain clamping force, so as to provide a more stable clamping force. Specifically, in the natural state, the angle a between the length direction of the clamping segment 643 and the axial direction of the fixing seat 20 is in the range of 0-150 degrees, that is, the angle between the two clamping segments 643 is the largest Up to 300 degrees, preferably 160-200 degrees, in this embodiment, the angle between the two clamping segments 643 is greater than 180 degrees.

In this embodiment, the tissue holding member 60 is entirely made of superelastic nickel-titanium alloy, so as to provide elastic force for the tissue holding member 60 to drive the holding arm 64 to move closer to the forceps arm 40 to hold the valve tissue and reduce production Process difficulty, simplify the process flow, and reduce production costs.

In other embodiments, different parts of the clamping arm 64 can be made of different materials separately and then fixedly connected. For example, the gripping section 643 of the gripping arm 64 is made of stainless steel to improve the gripping force, and the bending section 641 should have a bending function to provide the tissue gripper 60 with a natural unfolding state and a folded state that facilitates delivery. Therefore, The bent section 641 is made of shape memory material.

In this embodiment, each connecting piece 623 and the corresponding bending section 641 are connected by a bent fixing piece 625 , and the fixing piece 625 on each connecting piece 623 is bent toward the other connecting piece 625 . The segment 641 is bent away from the other bent segment 641 . Each connecting piece 623 is provided with a slot 6230 along its length direction, and the slot 6230 extends into the corresponding fixing piece 625 for cooperating and fixing with the fixing base 20 . The shape of the card slot 6230 can be a rectangle, an ellipse, a prism or other shapes. In this embodiment, a rectangle is preferred for higher stability. The base plate 621 , the two connecting pieces 623 and the two fixing pieces 625 enclose a connecting frame 62 with an open proximal end, the fixing seat 20 is accommodated in the inner cavity of the connecting frame 62 , and the drive shaft 72 is inserted through the opening of the proximal end of the connecting frame 62 . on the fixing base 20 and the connecting frame 62 . Specifically, the substrate 621 has a through hole 6210 , after the fixing seat 20 is accommodated in the inner cavity of the connecting frame 62 , the through hole 24 of the fixing seat 20 corresponds to the through hole 6210 of the substrate 621 , and the driving shaft 72 is inserted through the fixing seat 20 . The through hole 24 and the through hole 6210 of the substrate 621 . It can be understood that the fixing piece 625 should have a certain deformation ability to be clamped outside the fixing seat 20, so the fixing piece 625 should be made of shape memory material, and other parts of the connecting frame 62 can be made of relatively hard materials such as stainless steel. , thereby improving the connection strength. That is, the fixing piece 625 of the connecting frame 62 and the bending section 641 connected to it can be integrally formed with Nitinol, and the base plate 621 and the connecting piece 623 of the connecting frame 62 can be integrally formed with stainless steel and then welded or bonded to the fixing piece 625. , and each bending segment 641 is welded or bonded to the clamping segment 643 for fixing.

As shown in FIGS. 6-8 , the bending segment 641 includes a first end 6412 connected to the corresponding fixing piece 625 and a second end 6414 connected to the corresponding clamping segment 643 , and the bending segment 641 is a variable diameter structure That is, the width of the bent segment 641 at the first end 6412 is greater than the width of the bent segment 641 at the second end 6414 , and the width of the bent segment 641 gradually decreases from the first end 6412 to the second end 6414 . In this embodiment, the width of the first end 6412 of the bending section 641 is equal to the width of the fixing piece 625 , the width of the second end 6414 of the bending section 641 is equal to the width of the clamping section 643 , and the first end of the bending section 641 is equal to the width of the clamping section 643 . Smooth transition between 6412 and second end 6414. Since the valve clamping device 100 often needs to be repeatedly opened and closed during the operation, and the valve leaflets are often caught for many times, if the rebound stress of the clamping arm 64 is too large, the pulling force of the control wire is required to be higher. , will increase the risk of control wire breakage. The reduction structure of the bending section 641 can effectively reduce the stress of the clamping arm 64 in the folded state, thereby reducing the risk of breakage of the control wire. In addition, in the prior art, in order to reduce the stress, a hole is opened in the middle of the bending section, but microcracks are prone to appear at the opening position, and the microcracks are often difficult to observe, and the valve clamping device is implanted in the human body. The state of long-term stress The micro-cracks near the opening position are prone to fatigue fracture. Therefore, in this embodiment, the stress is reduced by the variable diameter structure, and the risk of fatigue fracture caused by the opening is avoided at the same time.

Preferably, the width ratio between the second end 6414 and the first end 6412 of the bent segment 641 ranges from 0.4 to 0.8; more preferably, the width ratio between the second end 6414 and the first end 6412 of the bent segment 641 ranges from 0.5 -0.65. If the ratio of the width of the second end 6414 to the first end 6412 is too large, that is, the width of the second end 6414 is too large, the stress of the bending section 641 in the retracted state of the clamping arms 64 is relatively large, and the required pulling force is relatively large. If the width ratio of the second end 6414 to the first end 6412 is too small, that is, the width of the second end 6414 is too small, the clamping force of the clamping arm 64 on the tissue will be affected , causing the clamping device 100 to slip off easily.

As shown in FIGS. 5-8 , the clamping section 643 of each clamping arm 64 is provided with at least one row of barbs 6433 along its length, and the end of each barb 6433 is rounded to avoid piercing the flap leaf. Specifically, the clamping section 643 includes a clamping piece 6431 connected with the second end 6414 of the bending section 641, and two barbs 6433 connected with both sides of the clamping piece 6431. In this embodiment, the clamping piece The number of barbs 6433 on each side of 6431 is four.

There is an angle between each barb 6433 and the clamping piece 6431, and the angle ranges from 30 degrees to 85 degrees, preferably 45 degrees to 65 degrees. Too large or too small an angle will increase the difficulty of capturing the valve leaflets. The included angle A between each barb 6433 and the clamping piece 6431 may be the same or different. In this embodiment, the included angle A between each barb 6433 and the clamping piece 6431 is 60 degrees.

The effective length of each barb 6433 is in the range of 0.3 mm to 2.0 mm, preferably 0.5 mm to 1.2 mm. The effective lengths of the barbs 6433 may or may not be the same. In this embodiment, the barbs in each row of barbs 6433 have the same extension length; specifically, the four barbs 6433 in the same bay on each side of the clamping piece 6431 extend from one end adjacent to the bending section 641 to the end The effective lengths of L1, L2, L3, and L4 are respectively, and L1=L2=L3=L4; in this embodiment, the effective lengths of L1, L2, L3, and L4 are all 0.8 mm.

As shown in FIG. 9 , in another embodiment of the tissue clamping member 60 , the included angle between the barbs in at least one row of barbs 6433 of each clamping segment 643 and the corresponding clamping segment 643 is along the clamping The extension direction of the holding arm gradually increases, and the effective length of the barbs 6433 from one end adjacent to the bent section 641 to the end also gradually increases. Specifically, the number of barbs 6433 in each row is four, and the included angles between the barbs 6433 from one end to the end of the adjacent bending segment 641 and the clamping segment 643 are A1, A2, A3, and A4, respectively, and A1 ≤A2≤A3≤A4; the effective lengths of the barbs 6433 from one end of the adjacent bending section 641 to the end are L1, L2, L3, and L4, respectively, and L1≤L2≤L3≤L4. In this embodiment, the angle of A1 is 45 degrees, the angle of A2 is 50 degrees, the angle of A3 is 55 degrees, and the angle of A4 is 60 degrees; the effective length of L1 is 0.4 mm, the effective length of L2 is 0.8 mm, and the effective length of L3 is 0.4 mm. The effective length of the L4 is 1.0 mm and the effective length of the L4 is 1.2 mm. The reason for this setting is that due to the uneven thickness of the valve leaflets, the edge of the valve leaflet is the thinnest, and the thickness gradually increases to the point where the valve leaflet connects with the valve annulus. Ensure that the force depth of each barb 6433 at different contact positions with the valve leaflet tissue is approximately the same, to ensure the clamping force of the clamping segment 643 to the valve leaflet, and not to pierce the valve leaflet, so as to adjust the angle of the barbs 6433 to Adapt to the force depth of leaflet tissue of different thicknesses.

As shown in FIG. 8 , the width D1 of the clamping section 643 (width D1 = the width of the clamping piece 6431 + the width of the barbs 6433 on both sides), the width D2 of the second end 6414 of the bending section 641 , and the fixing piece 625 The range of the ratio of the width D3 is (1.5~2):1:(1.5~2), that is, D1:D2:D3=(1.5~2):1:(1.5~2). In this embodiment, the width D1 of the clamping segment 643 : the width D2 of the second end 6414 of the bending segment 641 : the width D3 of the fixing piece 625 =1.5:1:1.5. If the width of D2 is too narrow, the fatigue resistance and tensile strength of the valve clamping device 100 will be reduced; if D2 is too wide, it means that the weight of the valve clamping device 100 will increase, which will cause the valve clamping device 100 to be implanted. After falling under the valve for a long time, it is not only easy to slip off, but also may strain the target tissue or even lead to cardiac dysfunction; and, since the tissue holder 60 is made of shape memory alloy, if D2 is too wide, the bent section 641 will be caused The compressed leaflets are subjected to greater pressure during the expansion and contraction of the heart, resulting in excessive tissue damage.

As shown in FIG. 10 and FIG. 11 , the distal end of the fixing piece 625 is connected to the connecting frame 62 , the proximal end of the fixing piece 625 is connected to the bending section 641 , and the fixing piece 625 is used to realize the mutual connection between the tissue clamping member 60 and the fixing seat 20 . The function of buckling and fixing prevents the tissue holder 60 from being displaced or loosened relative to the fixing seat 20 under the unilateral force of the control wire, thereby ensuring the reliability of the tissue holder 60 in the process of capturing the valve.

In this embodiment, the fixing piece 625 includes a first buckling position 6251 and a second buckling position 6253 . The first buckling position 6251 is to prevent the connection frame 62 from moving up and down after it cooperates with the fixing seat 20 , that is, it plays the role of limiting the position of the proximal and distal ends; Move left and right, that is, play the role of left and right limit. The radius of curvature of the proximal portion of the mount 20 is greater than the radius of curvature of the mount 625 . Specifically, the first buckling position 6251 is a curved piece corresponding to the first abutting curved surface 212 of the fixing base 20 , and the second buckling position 6523 is a curved piece corresponding to the second abutting curved surface 214 of the fixing base 20 , wherein The radius of curvature of the first engaging position 6251 is K3, and the radius of curvature of the second engaging position 6523 is K4. The radius of curvature K3 of the first buckling position 6251 is greater than the radius of curvature K1 of the first abutting curved surface 212 of the fixing seat 20 , and the radius of curvature K4 of the second buckling position 6253 is smaller than the radius of curvature of the second abutting curved surface 212 of the fixing seat 20 . K2, so that a first avoidance position P1 is reserved between the first abutting curved surface 212 and the first buckle position 6251, and a second avoidance position P2 is reserved between the second abutment curved surface 214 and the second buckle position 6523 , the contact point between the fixing piece 625 and the fixing frame 21 is just set between the first avoidance position P1 and the second avoidance position P2, so as to prevent the connection between the fixing piece 625 and the fixing seat 20 from interfering, thereby ensuring the first buckle position 6251 stability, that is, to ensure the stability of the proximal and distal limits.

As shown in FIG. 5 and FIG. 6 , when the fixing base 20 is accommodated in the connecting frame 62 , the two bosses 23 of the fixing base 20 are respectively clamped into the two slots 6230 of the tissue holder 60 , so that the fixing base 20 and the tissue holding member 60 are engaged with each other, so as to prevent the tissue holding member 60 and the fixing seat 20 from moving back and forth, that is, it plays the role of front and rear limit.

In order to ensure the safety after implantation, the fixing seat 20 and the forceps arm 40 are respectively made of biocompatible metal materials such as stainless steel, cobalt alloy, cobalt-chromium alloy, titanium alloy or nickel-titanium alloy; the driving component 70 is made of polyester, Silicone resin, stainless steel, cobalt alloy, cobalt chromium alloy or titanium alloy and other biocompatible polymer materials or metal materials. In this embodiment, the fixing base 20 , the clamp arm 40 and the driving assembly 70 are all made of stainless steel.

As shown in FIG. 12 , when the drive assembly 70 drives the clamp arm 40 to open and close relative to the fixed base 20 , the clamp arm 40 can be opened and closed relative to the fixed base 20 in a wide range, and the angle between the two clamp arms 40 can be realized. The maximum can reach 300 degrees, that is, after the forceps arm 40 is opened relative to the fixed seat 20, it can be turned downward to a certain extent, which is conducive to clamping the valve in motion, improving the success rate of clamping, and after clamping If the effect is found to be unsatisfactory, the valve leaflet can be released by flipping the forceps arm 40 downward and re-clamping. In this embodiment, the included angle range between the two clamp arms 40 is preferably 0-240 degrees, more preferably 120-180 degrees.

Preferably, a non-slip structure (not shown in the figure) may be provided on the surface of the forceps arm 40 facing the clamping section 643 to enhance the frictional force when the forceps arm 40 is in contact with the valve leaflet 300 , thereby providing a stable clamping force and enabling The leaflet 300 is prevented from being damaged by the forceps arm 40 . The anti-slip structure may be a protrusion or groove provided on the inner surface of the receiving groove 45 of the clamping frame 44 or a gasket made of a biocompatible material with a high friction coefficient attached to the inner surface of the receiving groove 45 .

Preferably, active drugs may also be applied on the inner surface of the receiving groove 45 of the forceps arm 40 and/or each clamping segment 643 to promote the endothelial cells of the valve tissue on the inner surface of the forceps arm 40 and the clamping arm 64 to crawl cover and grow.

It should be noted that the two gripping segments 643 of the tissue gripping member 60 are also provided with control wires respectively, and the gripping segments 643 can be pulled up to fit the central axis by pulling or loosening the control wires for convenient transportation; The pulling force on the clamping section 643 causes the clamping arm 64 to rebound and restore to its natural state due to its own elastic memory performance, and the clamping section 643 expands relative to the fixing seat 20 to press the valve leaflet 300 to the clamp arm 40 to clamp the valve leaflet 300. Specifically, the control wire may be a metal wire made of nickel-titanium alloy or the like, and since it has nothing to do with the improvement and creation of the present invention, it will not be repeated here.

The following takes the mitral valve repair process as an example to illustrate the operation method of the valve clamping device of the present invention, which mainly includes the following steps:

Step 1: The valve clamping device 100 is detachably connected to the distal end of the delivery device, and the control wire is pulled toward the proximal end to control the clamping arm 64 to retract relative to the fixed seat 20, so that the clamping section 643 of the clamping arm 64 is attached on the surface of the fixing base 20 . Then, the drive shaft 72 is moved proximally to drive the connecting rod 76 to drive the forceps arm 40 to close relative to the fixed seat 20, so that the valve clamping device 100 is in a fully retracted state, and both the tissue holding member 60 and the forceps arm 40 are close to the fixed seat 20 surface, keep the folded state unchanged.

The second step: femoral vein puncture, using a trans-atrial septal route, through the flexible sheath to advance the distal end of the delivery device and the valve clamping device 100 from the left atrium, through the mitral valve to the left ventricle.

Step 3: Adjust the relative positions of the valve clamping device 100 and the mitral valve, so that the valve clamping device 100 is close to the anterior and posterior leaflets of the mitral valve.

The fourth step: moving the drive shaft 72 toward the distal end, thereby driving the connecting rod 76 to drive the clamp arm 40 to open relative to the fixed seat 20 .

Step 5: withdraw the entire valve clamping device 100 toward the proximal end, so that the forceps arm 40 supports the valve leaflet on the left ventricle side.

Step 6: Release the control of each control wire to the corresponding clamping arm 64 to release the clamping arms 64 on both sides, and the clamping arms 64 on each side press the valve leaflet 300 on the atrial side and connect with the clamp arm on that side. 40 fits to hold the leaflets (as shown in Figure 13).

Step 7: Move the drive shaft 72 toward the proximal end, and the drive shaft 72 drives the connecting rod to drive the forceps arm 40 to close relative to the fixed seat 20 until the valve clamping device 100 is fully retracted.

Step 9: Release the connection between the valve clamping device 100 and the delivery device and the control wire, and withdraw the delivery device and the control wire from the patient's body. Pulled toward each other to obtain a bi-ported mitral valve, edge-to-edge repair of the mitral valve is completed, and the valve clamping device 100 is indwelled in the patient.

Please refer to FIG. 14 and FIG. 15 , the structure 100a of the valve clamping device provided by the second embodiment of the present invention is similar to the structure of the valve clamping device 100 in the first embodiment, the difference is that in the second embodiment The structure of the clamp arm 64a is slightly different from that of the clamp arm 64 in the first embodiment. Specifically, a curved portion 645 is provided between the clamping segment 643 of each clamping arm 64a and the corresponding bending segment 641, and the curved portion 645 is bent toward the side away from the connecting frame 62, so that the valve clamping device 100a can be In a natural state, the clamping section 643 of the clamping arm 64 is substantially parallel to the clamping frame 44 of the clamp arm 40 . Therefore, when the clamping arm 64a captures the valve leaflet, the gap between the barbs 6433 and the clamping frame 44 of the forceps arm 40 is relatively uniform, and the barbs 6433 can simultaneously contact the valve leaflet 300 to improve the success of capturing the valve leaflet 300 rate and stability.

Performance testing of tissue grippers and fatigue testing of valve gripping devices.

Tissue Holder Performance Testing

The same nickel-titanium alloy material and manufacturing process were used to make three groups of clamping arms, of which the first group was the tissue clamping member used in the present invention (the width and diameter of Examples A1-A4 in Figure 16), and the second group It is the constant diameter (equal diameter and equal width) tissue clamps in the prior art (the equal width and constant diameter of the comparative examples B1-B4 in FIG. 16 ), and the third group is the equal width tissue clamps in the prior art A tissue holder with holes formed by laser cutting on the holder (the equal-width openings of Comparative Examples C1-C4 in Figure 16), the following performance tests were performed on several groups of tissue holders respectively, and the test results are shown in Figure 16. shown.

1. Fatigue resistance test of tissue holder

To test the fatigue resistance of the tissue holder itself, the test equipment is the AWT-1000 artificial heart valve fatigue resistance tester of Shanghai Heart Valve Testing Equipment Co., Ltd. It is tested whether the tissue holder is fractured or cracked due to load during the fatigue test cycle. The test results are shown in Figure 16.

The fatigue resistance test parameters are as follows: cyclic tension (peak value): 0.80N±0.30N, amplitude: 1mm, frequency: 50Hz, water bath temperature: 37℃±0.5℃, cycle: ≥400 million times.

2. Test of the retraction force of the control wire on the tissue holder

The retraction force of the same control wire on three sets of tissue grippers was tested. The testing equipment is HY-0580 electronic universal tensile testing machine produced by Shanghai Hengyi Precision Instrument Co., Ltd. The test method is as follows: connect the valve clamping device to the simple handle, respectively use two U-shaped control wires to pass through the control holes of the two free ends of each clamping arm, and the control wires pass through the proximal end of the simple handle, Fix the simple handle on the machine table of the tension machine, the moving end of the tension machine hooks the proximal end of the control wire, move the moving end at a constant speed of 4.5mm/min, and record the tissue clamps are retracted to the basic gripping section on both sides. The force value in parallel, the test results are shown in Figure 16.

3. Control wire fatigue resistance test

The fatigue resistance of control wires of three groups of tissue holders was tested. The testing equipment is HY-0580 electronic universal tensile testing machine produced by Shanghai Hengyi Precision Instrument Co., Ltd. The test method is as follows: connect the valve clamping device to the simple handle, respectively use two U-shaped control wires to pass through the control holes of the two free ends of each clamping arm, and the control wires pass through the proximal end of the simple handle, The simple handle is fixed on the table of the tension machine, the moving end of the tension machine is hooked to the proximal end of the control wire, and the action of the tissue holder being closed and released under the control of the control wire is repeated, and the number of tests is 50 times. After the test, observe the control wire. If any of scratches, abrasions, cracks, and breaks occur, it is judged that the test has not passed. The test results are shown in Figure 16.

From the test results shown in Figure 16, it can be seen that:

1). The present invention can effectively reduce the retraction force required to control the retraction of the tissue clamp by setting the reducing structure on the tissue clamp, which can not only ensure the fatigue resistance of the control wire, but also ensure the tissue clamp itself. Fatigue resistance;

2). The tissue holder in the prior art is not provided with a variable diameter structure, and the required retraction when controlling the tissue holder is significantly larger. Although it can ensure the fatigue resistance of the tissue holder itself, it cannot guarantee the control wire. fatigue resistance;

3). The opening of the tissue holder in the prior art can reduce the retraction force required to control the retraction of the tissue holder and ensure the fatigue resistance of the control wire, but cannot guarantee the fatigue resistance of the tissue holder itself. .

In conclusion, compared with the prior art, the tissue holder of the present invention has better fatigue resistance, requires less pulling force and retracting force, and lowers the risk of breakage of the control wire.

Valve clamping device fatigue test

It is verified by fatigue test whether the valve clamping device using the tissue clamping member of the present invention can meet the load for 10 years of implantation as a medical device implant after clamping the two leaflets of the mitral valve. Before the test, the artificial mitral valve model was fixed with a valve clamping device to simulate the edge-to-edge treatment effect, and then the mitral valve model with the valve clamping device was placed in a fatigue testing machine that simulates the beating of the left heart system of the human heart. , carry out non-destructive fatigue test, record the sliding of valve clamping device due to load and damage to valve leaflet during the fatigue test cycle.

Test equipment: AWT-1000 artificial heart valve fatigue resistance tester of Shanghai Heart Valve Testing Equipment Co., Ltd.

Test standard: Test according to the method of "fatigue test" in ISO 5840 and GB12279-2008 "Cardiovascular Implant Prosthetic Heart Valve", cycle: ≥400 million times, the test result is that the valve clamping device of this embodiment satisfies According to relevant requirements, the valve clamping device did not slide during the test period, and the valve clamping device did not cause damage to the valve leaflets.

It should be noted that the above contents are all described by taking the valve clamping device for alleviating or treating "mitral regurgitation" as an example. It can be understood that, in other embodiments, the valve clamping device can also be used to alleviate or treat "tricuspid valve regurgitation", and its principle and structure are the same as those used to solve "mitral valve regurgitation" in the embodiments of the present invention. The principle and structure of the valve clamping device are basically the same, and it is only necessary to form multiple clamps by multiple sets of proximal clamps and distal clamps, and each clamp can clamp a valve leaflet respectively, which will not be repeated here. .

The above are the implementations of the embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principles of the embodiments of the present invention, several improvements and modifications can also be made. These improvements and modifications are also It is regarded as the protection scope of the present invention.

Claims (15)

1. A tissue holder, characterized in that, comprising: a connecting frame, the connecting frame includes two connecting pieces opposite to each other at intervals; Two clamping arms, the two clamping arms are respectively disposed on the opposite sides of the two connecting pieces, each of the clamping arms extends to a side away from the other clamping arm, each of the clamping arms The clamping arm includes a bending section connected to the corresponding connecting piece and a clamping section connected to the bending section away from the corresponding connecting piece, and the width of the bending section is smaller than the width of the clamping section and less than the width of the connecting piece. 2 . The tissue holder according to claim 1 , wherein each connecting piece is connected with the corresponding bending segment by a bent fixing piece, and the fixing piece on each connecting piece faces the other connecting piece. 3 . Bend, each bend segment bends away from the other bend segment. 3 . The tissue clamp of claim 2 , wherein the bending segment comprises a first end connected to the corresponding fixing piece, and a second end connected to the corresponding clamping segment, 3 . The width of the bent segment at the first end is greater than the width of the bent segment at the second end. 4. The tissue clamp of claim 3, wherein the width of the bent segment gradually decreases from the first end toward the second end. 5 . The tissue holder according to claim 3 , wherein the width of the first end of the bending segment is equal to the width of the fixing piece, and the width of the second end of the bending segment is equal to the width of the clamping segment. 6 . width, a smooth transition between the first end and the second end of the bent segment. 6. The tissue gripper of claim 1, wherein the gripping section of each gripping arm is provided with at least one row of barbs along its length. 7. The tissue holder of claim 6, wherein the end of each of the barbs is rounded. 8. The tissue gripper of claim 6, wherein the extension lengths of the barbs in the at least one row of barbs gradually increase along the extension direction of the gripping arms. 9 . The tissue gripper according to claim 6 , wherein the angle between the barbs in the at least one row of barbs and the corresponding gripping segments gradually increases along the extending direction of the gripping arms. 10 . Increase. 10 . The tissue clamp of claim 1 , wherein a curved portion is provided between the clamping segment of each clamping arm and the corresponding bending segment, and the curved portion faces away from the connecting frame. 11 . bent on one side. 11. The tissue gripper of claim 1, wherein the tissue gripper is at least partially made of a shape memory material, the tissue gripper having a natural expanded state and a collapsed state. 12. The tissue gripper according to claim 11, wherein the bending section is made of a shape memory material, and in a natural state of the tissue gripper, the gripping sections of the two gripping arms The angle between them is greater than 180 degrees. 13. A valve clamping device, characterized in that it comprises a fixed seat, a pair of forceps arms that open and close relative to the fixed seat, and the tissue holding member according to any one of claims 1 to 12, The tissue clamping member is arranged between the fixing seat and the forceps arm, and the two clamping arms of the tissue clamping member are respectively matched with one of the pair of forceps arms to clamp the valve leaflets . 14 . The valve clamping device according to claim 13 , wherein the fixing seat is accommodated in a connecting frame, at least one connecting piece of the connecting frame is provided with a card slot, and the fixing seat is provided with a card slot. 15 . The protrusion is buckled in the slot. 15. The valve clamping device according to claim 14, wherein each connecting piece is connected with the corresponding bending segment by a bent fixing piece, and the radius of curvature of the proximal portion of the fixing seat is greater than The radius of curvature of the fixed piece.

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