Suture catheters and related systems for percutaneous relief of mitral regurgitation

Abstract

At least one suture thread (1) folded into a "U" shape, each end of the suture thread is provided with a suture needle (13); at least one pair of probes (12), each probe is provided with a capture needle (15); the capture needle (15) is provided with a first connection part (152), and the suture needle (13) is provided with a second connection part (132), and the first connection part (152) and the second connection part (132) can enable the capture needle (15) and the suture needle (13) to be mechanically engaged; a lever (110), which includes a stapling arm (112), the suture needle (13) extends from the stapling arm, and the capture needle (15) extends from the catheter body, and the stapling arm and the suture catheter body (101) together define the capture area (113) of the cusp of the mitral valve; a relative operating arm (114), which together with the suture catheter body (101) defines the operating area (115) of the lever (110).

Description

[0001] The object of the present invention is to provide a suture catheter for relieving mitral regurgitation by percutaneous application of suture points, and a related system for relieving mitral regurgitation by percutaneous application of suture points ("edge-to-edge" technique).

[0002] Mitral regurgitation is a heart condition that affects the mitral valve, one of the four valves located within the heart that regulates the passage of blood between the left atrium and the left ventricle. The mitral valve consists of two cusps, including a posterior cusp (thicker) and an anterior cusp attached to a base (mitral annulus), with the free edge of each cusp surrounded by chordae tendineae attached to the papillary muscles.

[0003] Under physiological conditions, during diastole when the ventricles are filling, blood flows from the left atrium to the left ventricle through the opening of the mitral valve. During systole, when the ventricles contract and empty, the mitral valve closes rapidly, preventing blood from flowing back from the left ventricle to the left atrium.

[0004] When the mitral valve does not close properly during the emptying phase of the left ventricle, some blood can flow back into the left atrium, a condition known as mitral regurgitation.

[0005] Moderate to severe mitral regurgitation is traditionally treated by open heart surgery (open heart surgery) because the disease has a high mortality rate of 5% per year in addition to disability (dyspnea (due to exertion), palpitations, functional impairment).

[0006] Surgical correction of mitral regurgitation can be performed based on different techniques, including, for example, the "edge-to-edge" technique developed by Professor Ottavio Alfieri. In this procedure, the two cusps of the mitral valve are connected at their central part with suture points (the so-called "Alfieri suture") to form a double outlet mitral valve.

[0007] In recent years, a technique has been developed to repair the mitral valve percutaneously using an "edge-to-edge" technique without the need for conventional surgery such as thoracotomy, cardiac arrest, and extracorporeal circulation. This technique is based on the use of a small metal prosthesis that is placed in the heart under the guidance of transesophageal angiography, radiology, and echocardiography through a complex control system. An example of such a prosthesis is shown in U.S. Patent Document 2012 / 0041453A1.

[0008] However, there are some disadvantages to using such prostheses or clips. In some cases, it is impossible to position the clip because the cusp is too damaged. Often, more than one clip cannot be placed at a single suture point. In addition, the clip cannot be removed when it is not positioned correctly.

[0009] The use of a suture catheter to percutaneously apply suture points for relieving mitral regurgitation is known in the art, for example as shown in documents US2019 / 150903A1 or US2011 / 190793A1.

[0010] The object of the present invention is to provide a system for alleviating mitral regurgitation which is both simple and safe.

[0011] In particular, it is an object of the present invention to provide a system for the percutaneous application of suture points by an "edge-to-edge" technique to relieve mitral regurgitation.

[0012] Furthermore, it is an object of the present invention to provide a system for alleviating mitral regurgitation which is capable of percutaneously providing at least one suture point even on a very deteriorated cusp of the mitral valve, as well as percutaneously providing multiple suture points when necessary, and also of removing any suture points that are poorly percutaneously positioned.

[0013] The above objects are achieved by a suture catheter for relieving mitral regurgitation by percutaneously applying suture points, and a related system for relieving mitral regurgitation by percutaneously applying suture points ("edge-to-edge" technique).

[0014] The features and advantages of the catheter and system for alleviating mitral regurgitation according to the invention will become apparent from the following description of non-limiting examples based on the accompanying drawings. In the drawings:

[0015] Figure 1A shows a cross-sectional view of a heart into which components of the system for alleviating mitral regurgitation according to the present invention are inserted, in particular a suture catheter in a positioning step;

[0016] Figure 1B Shows Figure 1A details, especially the approach of the suture catheter to the cusp of the mitral valve;

[0017] Figure 2A The step of applying suture points on the cusp of the mitral valve is shown. Figure 1A Suture catheters;

[0018] Figure 2B Shown from different angles Figure 2A The suture catheter in the to better show the application of the suture point;

[0019] Figure 3A A suturing catheter in a closed advancement configuration according to the present invention is shown;

[0020] Figures 3B to 3D Shown in detail Figure 3A Components of a suture catheter;

[0021] Figure 4A A suture catheter according to the present invention is shown in a configuration for applying a suture point;

[0022] Figures 4B to 4D Shown in detail Figure 4A Components of a suture catheter;

[0023] Figure 5A Another component of the system for alleviating mitral regurgitation according to the present invention is shown, in particular, a knotting catheter for knotting suture wire;

[0024] Figure 5B Shows Figure 5A Details of the suture threads;

[0025] Figure 6 Another component of the system for alleviating mitral regurgitation according to the present invention is shown, in particular a cutting catheter for cutting suture wires.

[0026] Figure 1A A cutaway heart C is shown in which there is a defect in the mitral valve VM, whose function is to regulate the passage of blood between the left atrium AS and the left ventricle VS. The mitral valve is formed by two cusps, the posterior one being called LP (larger) and the anterior one being called LA.

[0027] like Figures 1A to 4D As shown, the system for alleviating mitral regurgitation according to the present invention includes at least one suture catheter 100 .

[0028] The suturing catheter 100 includes a suturing catheter body 101 extending between a proximal end (not shown) and a first distal end 102 .

[0029] Preferably, the first distal end 102 is closed and may be rounded and / or tapered to avoid suturing the catheter 100 when advancing the suture catheter 100 to the distal end. Figure 1A damage or puncture cardiac tissue during the working position.

[0030] like Figure 3D As shown, the suture catheter body 101 is provided with at least one inner cavity, which is defined as a suture cavity 103 and is suitable for accommodating the suture wire 1 that can slide therein.

[0031] In particular, the suture wire 1 is folded into a “U” shape, with the connecting portion (not shown) of the suture wire facing the proximal end of the suture catheter body 101 and the two free ends 11 of the suture wire facing the distal end of the suture catheter body 101 .

[0032] Therefore, from Figure 3D It can be seen that the two free ends 11 of the same suture thread 1 are connected together at the downstream and slide in parallel in the suture cavity 103 .

[0033] like Figure 3C As shown, the two free ends 11 of the suture thread 1 are located at the distal end position in the suture catheter body 101. Each free end 11 of the suture thread 1 is connected to a suture needle 13. Therefore, the suture thread 1 is connected to a pair of suture needles 13.

[0034] Preferably, the suture needle 13 is elastic and flexible, made of Nitinol, thus having shape memory, and has a straight trajectory.

[0035] like Figure 3D As shown, the suture catheter body 101 is also provided with an inner cavity defined as a capture cavity 104, which is suitable for accommodating a pair of stylets 12 that can slide therein.

[0036] Therefore, from Figure 3D It can be seen that the two probes 12 slide in parallel in the capture chamber 104 .

[0037] like Figure 3C As shown, the distal end of the probe 12 is disposed at the distal end position of the suture catheter body 101. The distal end of the probe is connected to the corresponding capture needle 15. Therefore, inside the suture catheter body 101, a pair of capture needles 15 are disposed at the distal end position.

[0038] Preferably, suture cavity 103 has a cross section that is roughly 8-shaped or groove-shaped. This shape allows suture needle 13 to remain in the correct position, that is, side by side and relative to each other (such as) at corresponding capture pin 15 places. Figure 3C As shown), the U-shaped connecting portion of the suture thread 1 is allowed to slide.

[0039] The capture chamber 104 has a substantially 8-shaped or elliptical cross section and accommodates two probes 12 at the same time.

[0040] In a modified embodiment not shown, the suture catheter body 101 is provided with a pair of parallel capture cavities 104, each of which is suitable for accommodating a probe 12 sliding therein.

[0041] Therefore, the suturing cavity 103 and the capturing cavity 104 extend in parallel within the suturing catheter body 101 (eg, Figure 3D In other words, it is important that the plane where the axes of the two free ends 11 of the suture thread 1 are located is parallel to the plane where the axis of the probe 12 is located.

[0042] from Figure 4D As can be seen in FIG. 1 , each capture needle 15 is provided at its end with a piercing tip 151 suitable for piercing the cusp of the mitral valve.

[0043] The catching needle 15 and the suturing needle 13 are both provided with a connecting portion at their free ends, which is suitable for allowing the catching needle 15 to be mechanically engaged with the corresponding suturing needle 13 (such as Figure 4D shown).

[0044] The suturing needle 13 has a second connection portion 132, which is preferably in the form of a through hole, a slit, or a groove. The capturing needle 15 has a first connection portion 152, which is preferably in the form of a harpoon or a hook.

[0045] Back to Figure 3A The suture catheter 100 includes a lever 110 at its distal end portion, which is connected to the suture catheter body 101 via a pin 111, which forms a fulcrum of the lever 110. Therefore, the suture catheter body 101 and the lever 110 together define a stapling structure 109 for the suture catheter 100.

[0046] The lever 110 includes a stapling arm 112 which, together with the suturing catheter body 101, defines a capture region 113 of the cusp of the mitral valve.

[0047] Preferably, the suturing cavity 103 extends at least partially into the interior of the stapling arm 112. Thus, the suturing cavity 103 has an initial straight path in the suturing catheter body 101, a curved path in the passage area toward the lever 110, and finally a straight path again in the stapling arm 112. It should be noted that the suturing needle 13 is disposed inside the stapling arm 112 and is at least partially located at the bend of the suturing cavity 103 ( Figure 3C ).

[0048] The staple arm 112 is provided with a joint opening 119 in the form of a through hole, preferably a slit. At the joint opening 119, the connecting portion of the catching needle 15 and the connecting portion of the suturing needle 13 meet and engage with each other (such as Figure 4D shown).

[0049] The suture lumen 103 terminates at the engagement opening 119 with a distal outlet 107 obtained in the suture arm 112. The capture lumen 104 terminates with a distal outlet 108 obtained in the suture catheter body 101, which is directed toward the engagement opening 119.

[0050] Thus, the suturing catheter 100 includes two suturing needles 13 (in parallel) and two capturing needles 15 (in parallel), and they are contained within respective channels (the suturing cavity 103 and the capturing cavity 104 ) that open toward the engagement opening 119 .

[0051] The lever 110 also includes an opposing operating arm 114 , which together with the suturing catheter body 101 defines an operating area 115 of the stapling structure 109 .

[0052] Preferably, the capture area 113 is disposed at a position close to the fulcrum 111 and / or the operating area 115 .

[0053] like Figure 3D As shown, the suture catheter body 101 is further provided with an inner cavity, which is defined as a control cavity 105 and is suitable for accommodating the control core shaft 16 slidably therein.

[0054] Preferably, the control chamber 105 has a substantially circular cross-section.

[0055] like Figure 3C As shown, the distal end of the control mandrel 16 is disposed at a distal position within the suturing catheter body 101. The distal end of the control mandrel 16 is connected to the operating arm 114 of the lever 110 via a connecting device 161. By retracting the control mandrel 16, the operating arm 114 is pulled into the closed position of the stapling structure 109. By advancing the control mandrel 16, the connecting device 161 pushes the operating arm 114 into the open position of the stapling structure 109.

[0056] Preferably, the connecting device 161 is a relatively rigid ring engaged with the operating arm 114. This solution is preferred because the traction force on the operating arm 114 will be better distributed.

[0057] In an alternative example, the connection device is a pull wire that engages the operating arm 114 .

[0058] By controlling the mandrel 16 in the closed position (such as Figure 3A ) and the open position (as Figure 4A As shown in the figure, the operating arm 114 is operated to operate the stapling structure 109 of the suturing catheter 100.

[0059] In use, the suturing catheter 100 is advanced when the stapling structure 109 is in the closed position ( Figure 1B Once the area to be treated is reached, the control mandrel 16 is advanced, thereby pushing the operating arm 114 of the lever 110 toward the open configuration of the stapling structure 109 ( Figure 4A It should be noted that the operating arm 114 of the lever 110 is also pushed toward the open configuration of the stapling structure 109 by the blood flow and the elastic force of the suture needle 13, which has a straight configuration when idle and is now pressed into the curved portion of the suture cavity 103.

[0060] The suturing catheter 100 is retracted with the staple structure 109 open until the suturing catheter 100 captures the cusp LP of the mitral valve in the capture area 113. By retracting the control mandrel 16, the operating arm 114 of the lever 110 is pulled toward the closed state of the staple structure 109, thereby clamping and firmly holding the cusp LP of the mitral valve in the capture area 113.

[0061] At this time, the distal outlet 107 of the suturing cavity 103 is aligned with the distal outlet 108 of the capturing cavity 104. The capturing needle 15 is advanced, and the capturing needle 15 pushes the corresponding probe 12 so as to pierce the cusp LP of the mitral valve from one side to the other. The capturing needle 15 is advanced to the inside of the engagement opening 119, where the capturing needle 15 (by its harpoon shape) is aligned with the corresponding suturing needle 13 ( Figure 4A ) for mechanical joining.

[0062] By retracting the probe 12 and the catching needle 15 connected to the probe 12, the suture needle 13 in the suture cavity 103 and the suture filament 1 connected to the suture needle 13 can be dragged until the U-shaped connecting part of the filament itself is located on the cusp LP of the mitral valve. In this way, a suture point is obtained.

[0063] Due to the presence of the suture needle 13 , the two free ends 11 of the suture filament 1 are inserted into a microcatheter 20 , preferably a monorail catheter, which allows the suture catheter 100 to be removed without friction of the ends of the suture filament 1 .

[0064] The above operation is repeated to position a second suture point on the cusp LA of the opposing mitral valve, and if necessary, a third or fourth suture point may also be positioned.

[0065] Preferably, if Figure 5A and 5B As shown, the system for alleviating mitral regurgitation according to the present invention further comprises at least one knotting catheter 200 for knotting the suture wire 1 .

[0066] The knotting catheter 200 includes a knotting catheter body 201 extending between a proximal end (not shown) and a second distal end 202 terminating in a second distal opening 203 .

[0067] The knotting catheter body 201 is provided with at least one inner cavity, which is defined as a receiving cavity 204, suitable for receiving at least one microcatheter 20 sliding therein, wherein the microcatheter 20 contains a suture wire 1 for forming a suture point on the cusp LP of the mitral valve and previously positioned together with the suture catheter 100.

[0068] At the second distal end 202 , preferably along the edge of the knotting catheter body 201 , a second distal opening 203 is defined, accommodating a tightening wire 210 , which is suitable for connecting the two free ends 11 of the suture wire 1 together.

[0069] The tightening wire 210 includes a loop (not shown because it is housed in a dedicated base 214), a slip knot 211, a contraction tongue 212 that can reduce the diameter of the loop, and a fixing tongue 213 that can tighten the slip knot 211. Preferably, the contraction tongue 212 and the fixing tongue 213 are different in geometry, surface, or color so that they can be easily distinguished.

[0070] The loop is received in a base 214 (eg, an annular base) located at the edge of the knot tying catheter body 201 , defining a second distal opening 203 .

[0071] The base 214 is provided with an opening portion 215 which is also annular and is obtained by pre-cutting or pre-cutting or weakening.

[0072] Preferably, the opening portion 215 faces the interior of the accommodating cavity 204 .

[0073] During use, a microcatheter 20 containing a suture thread 1 is inserted into a knotting catheter 200. The second distal end 202 of the knotting catheter 200 gradually approaches the cusps LP and LA, and at least one suture point has been placed on each cusp. By approaching the knotting catheter 200, and keeping the end of the suture thread 1 under tension, and by reducing the cross-section of the mitral valve, the two cusps of the mitral valve are brought closer together, thereby obtaining the desired effect of the Alfieri operation. In this step, the effectiveness of the cross-section reduction can be evaluated, and it can be modified based on the degree of remaining mitral regurgitation (by placing the knotting catheter 200 more or less forward). Once the optimal remaining cross-section is determined, the suture threads are knotted together. In particular, by pulling the contraction tongue 212 of the tightening thread 210, the diameter of the ring is reduced, and the ring comes out of the base 214 through the opening portion 215. The diameter of the ring is continuously reduced until all the suture threads 1 are surrounded in a bundle. At this time, by pulling the fixing tongue 213 of the tightening wire 210, the slip knot 211 is tightened to lock the loop in a position for tightening the suture wire 1. Once the suture wire 1 has been knotted, the knotting catheter 200 can be removed.

[0074] Preferably, if Figure 6 As shown, the system for alleviating mitral regurgitation according to the present invention further comprises at least one cutting catheter 300 , which is used to cut the ends of the suture wire 1 and the tightening wire 210 .

[0075] The cutting catheter 300 includes a cutting catheter body 301 extending between a proximal end (not shown) and a third distal end 302 terminating in a third distal opening 303 .

[0076] The cutting catheter body 301 is provided with at least one inner cavity, which is defined as a main cavity 304 and is suitable for receiving the end of the suture wire 1 and the end of the tightening wire 210 sliding therein, wherein the suture wire 1 previously forms a suture point on the cusp LP of the mitral valve positioned by the suture catheter 100.

[0077] The main cavity 304 contains a stop member 305 against which the blade 306 stops.

[0078] The cutting catheter body 301 is provided with another lumen, defined as a secondary lumen 308 , which is adapted to receive the blade 306 and an associated manipulating spindle 307 .

[0079] In the idle state, the blade 306 is housed in the secondary chamber 308 so as not to interfere with the filaments sliding in the main chamber 304. By retracting the mandrel 307, the blade 306 comes out of the secondary chamber 308, toward the main chamber 304 and is located inside the main chamber 304. The blade intercepts the filaments until they are pushed against the abutment element 305, so that they can be cut.

[0080] During use, the suture wire 1 and / or the tightening wire 210 are inserted into the cutting catheter 300. The third distal end 302 of the cutting catheter 300 is moved toward the cusps LP and LA until the desired position is reached. At this time, the blade 306 can be manipulated to cut the aforementioned filaments.

[0081] The novelty of the present invention is that the catheter and system for alleviating mitral regurgitation according to the present invention are easy to use, safe and extremely effective.

[0082] One advantage of the present invention is that the system for alleviating mitral regurgitation according to the present invention allows for the treatment of mitral regurgitation by percutaneous application of suture points through an "edge-to-edge" technique.

[0083] One advantage of the present invention is that the catheter and system for alleviating mitral regurgitation according to the present invention are capable of creating at least one suture point even on the cusp of a severely damaged mitral valve.

[0084] One advantage of the present invention is that the system for alleviating mitral regurgitation according to the present invention can position multiple suture points on the cusp of the same mitral valve when needed.

[0085] One advantage of the present invention is that the system for alleviating mitral regurgitation according to the present invention can remove any improperly positioned suture points.

[0086] It is obvious that those skilled in the art may modify the above objects without departing from the scope of protection defined in the following claims.

Claims

1. A suture catheter (100) for relieving mitral regurgitation by percutaneously applying a suture point, comprising: A suturing catheter body (101) having a first distal end (102) and at least one lumen, wherein the at least one lumen has a suturing lumen (103) and a capturing lumen (104); At least one suture thread (1) capable of sliding in an inner cavity defined as the suture cavity (103), the suture thread (1) being folded into a "U" shape, and the two free ends (11) of the suture thread being arranged at the first distal end (102) of the suture catheter body (101); at least one pair of suture needles (13), each suture needle being connected to a corresponding free end (11) of the suture thread (1); at least one pair of probes (12) slidable in an inner cavity defined as the capture cavity (104), each pair of probes having a distal end disposed at the first distal end (102) of the suture catheter body (101); At least one pair of capture needles (15), each capture needle being connected to the distal end of a corresponding probe (12), wherein the capture needle (15) is provided with a first connection portion (152), and the suturing needle (13) is provided with a second connection portion (132), and the first connection portion (152) and the second connection portion (132) are capable of mechanically engaging the capture needle (15) with the corresponding suturing needle (13); A lever (110) connected to the first distal end (102) of the suture catheter body (101) via a pin (111), the lever (110) comprising: A stapling arm (112) including the suturing needle (13), which together with the suturing catheter body (101) including the capturing needle (15) defines a capturing area (113) of the cusp of the mitral valve; An opposing operating arm (114) is connected to the control mandrel (16) via a connecting device (161), and the operating arm (114) and the suturing catheter body (101) together define an operating area (115) of the lever (110).

2. The suture catheter (100) according to claim 1, wherein: The probes (12) slide in parallel in the same capture chamber (104), or slide in parallel in a plurality of separate and parallel capture chambers (104).

3. The suture catheter (100) according to claim 1 or 2, wherein: The suturing cavity (103) and / or the capturing cavity (104) has a portion that is generally in the shape of an "8" or a groove.

4. The suture catheter (100) according to claim 1 or 2, wherein: The suturing cavity (103) and the capturing cavity (104) extend in parallel within the suturing catheter body (101), so that the plane where the axes of the two free ends (11) of the suture thread (1) lie is parallel to the plane where the axes of the two probes (12) lie.

5. The suture catheter (100) according to claim 1 or 2, wherein: The second connection portion (132) of the suturing needle (13) is in the form of a through hole, and the first connection portion (152) of the capturing needle (15) is in the form of a harpoon.

6. The suture catheter (100) according to claim 1 or 2, wherein: At least a portion of the suturing cavity (103) also extends into the interior of the stapling arm (112), which initially has a curved shape and ends in a straight shape, wherein at least a portion of the suturing needle (13) is disposed in the curved portion.

7. The suture catheter (100) according to claim 1 or 2, wherein: The stapling arm (112) is provided with a coupling opening (119), the suturing cavity (103) leads to the coupling opening (119), and the capturing cavity (104) faces the coupling opening (119), and the first connecting portion (152) of the capturing needle (15) is coupled with the second connecting portion (132) of the suturing needle (13) in the coupling opening (119).

8. The suture catheter (100) according to claim 1 or 2, wherein: The connecting device (161) is a rigid ring joined to the operating arm (114).

9. A system for relieving mitral regurgitation by percutaneously applying suture points, comprising: at least one pair of suturing catheters (100) according to any one of claims 1 to 8, each of which positions at least one suturing point on the cusp of the mitral valve; at least one knotting catheter (200) for tying a knot on a suture thread defining a suture point located by the suture catheter (100); and At least one cutting catheter (300) for cutting the suture filament (1).

10. A system for relieving mitral regurgitation by percutaneously applying suture points according to claim 9, wherein: The knotting catheter (200) comprises: A knotting catheter body (201) having a second distal end (202) and at least one receiving cavity (204) terminating at a second distal end opening (203); at least one tightening thread (210) for tying a knot on the suture thread (1), the tightening thread (210) comprising a loop, a slipknot (211), a contraction tongue (212) capable of reducing the diameter of the loop, and a fixing tongue (213) capable of tightening the slipknot (211); and A base (214) for the loop of the tightening wire (210), the base (214) being arranged in the second distal opening (203) in the knotting catheter body (201), the base (214) being provided with an openable portion (215), the openable portion being used to allow the loop to come out when tying a knot on the suture wire (1).

11. A system for relieving mitral regurgitation by percutaneously applying suture points according to claim 10, wherein: The cutting catheter (300) comprises: a cutting catheter body (301) having a third distal end (302) having at least one main lumen (304) terminating in a third distal end opening (303); and At least one blade (306) is used to cut the suture wire (1) and / or the tightening wire (210), and the blade is controlled by a control mandrel (307).

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