INSTRUMENT FOR REPAIRING AN ATRIOVENTRICULAR HEART VALVE

Abstract

An instrument for repairing an atrioventricular heart valve, mitral heart valve or tricuspid heart valve includes a first tube having a tube axis defining an axial direction. A leaflet grabbing structure is arranged at a distal part of the first tube and contiguous to the first tube. The leaflet grabbing structure has a main body and a jaw, the jaw being movable relative to the main body. The jaw has a first proximally facing abutment surface and the main body has a second, distally facing abutment surface. The instrument has a needle that is cannulated and forms an inner tube. The needle is releasable from the first tube and movable relative to the main body in axial directions. The leaflet grabbing structure clamps a leaflet of the heart valve between the first and second abutment surfaces, while the jaw allows the needle to extend therethrough.

Claims

1. An instrument for repairing an atrioventricular heart valve in a minimally invasive manner, the instrument comprising: a tubular arrangement defining an axis and an axial direction; a leaflet grabbing structure, the leaflet grabbing structure comprising a main body and a jaw; wherein the jaw comprises a first proximally facing abutment surface and the main body comprises a second, distally facing abutment surface; the instrument further comprising a needle, wherein the needle is cannulated and forms an inner tube, and wherein the needle is movable relative to the main body in axial directions, whereby the leaflet grabbing structure is capable of clamping a leaflet of the heart valve between the first and second abutment surfaces; and wherein the main body and the jaw have a channel being formed to allow the needle to extend there through while the leaflet is being clamped.

2. The instrument according to claim 1, wherein the channel has a position that is not central with respect to the tube axis.

3. The instrument according to claim 1, wherein the jaw is movable relative to the main body in the axial direction.

4. The instrument according to claim 1, wherein the instrument further comprises an anchor carrier being arranged within the inner tube and being axially movable relative to it, the anchor carrier being configured to carry at least a part of an implant that is secured or capable of being secured to an artificial chord.

5. The instrument according to claim 4, being configured for a distal implant part and a proximal implant part being arranged beside one another, with the proximal implant part arranged proximally of the distal implant part, wherein the anchor carrier forms an anchor seat is configured to carry the proximal implant part of the implant.

6. The instrument according to claim 5, wherein the inner tube or a sleeve element inside the inner tube prevents the proximal implant part from escaping from the anchor carrier as long as the anchor carrier is received in the anchor seat and is within the inner tube or sleeve element.

7. The instrument according to claim 4, wherein the anchor carrier comprises a marker for determining a position by echography and/or radiography, and wherein the main body and/or the jaw comprises a marker for determining a position by echography and/or radiography, for determination of relative positions of the anchor carrier and of the main body and/or jaw.

8. The instrument according to claim 1, wherein the channel is open to a lateral side.

9. The instrument according to claim 8, wherein the channel has a main body channel and a jaw channel aligned with the main body channel, wherein the jaw channel is open to the lateral side along its full axial length.

10. The instrument according to claim 9, wherein also a distal portion of the main body channel is open to the lateral side.

11. The instrument according to claim 10, wherein the channel is open to the lateral side by a recess that has a distal recess portion and proximally thereof, an implant release portion, wherein the implant release portion of the recess runs in the main body, and wherein the implant release portion of the recess is wider than the distal recess portion.

12. The instrument according to claim 11, wherein the distal recess portion has a first sub-portion running in the jaw and a second sub-portion running in the main body, distally of the implant release portion.

13. The instrument according to claim 10, wherein an opening angle α of a lateral recess by which the channel is open to the lateral side is at least 45°.

14. The instrument according to claim 8, further comprising a needle guide being a tube encompassing the cannulated needle and being accommodated inside the channel.

15. The instrument according to claim 8, wherein the channel is open a single lateral side.

16. The instrument according to claim 1, wherein the first and second abutment surfaces at a position around a mouth of the channel in the first and second abutment surfaces, define at least one plane being at an angle different from 90° to the tube axis.

17. The instrument according to claim 16, wherein a distal end of the needle defines a distal needle end plane that is at an angle different from 90° to the axis, and wherein the distal needle end plane and the plane defined by the first and second abutment surfaces are inclined in different directions.

18. The instrument according to claim 1, further comprising an operating mechanism suitable to operate the axial movement of the jaw relative to the main body and to adjust the distance between the main body and the jaw, wherein the operating mechanism comprises a push-pull rod or a threaded rod.

19. The instrument according to claim 18, further comprising at least one guiding rod configured to prevent non-axial movements of the jaw relative to the main body.

20. The instrument according to claim 1, wherein the main body and the jaw further comprise a guide wire channel suitable to incorporate a guide wire.

21. The instrument according to claim 1, wherein the needle has a sharpened distal end and proximally therefrom a laser cut section.

22. The instrument according to claim 1, wherein the tubular arrangement comprises a first tube, wherein the leaflet grabbing structure is arranged at a distal part of the first tube and is contiguous to the first tube, and wherein the needle is releasable from the first tube and movable relative to the main body in axial directions.

23. The instrument according to claim 1, wherein the tubular arrangement comprises an outer catheter being configured as a guide catheter, the outer catheter being dimensioned to accommodate the leaflet grabbing structure within an interior of the outer catheter.

24. The instrument according to claim 1 wherein the jaw and the main body each comprise a marker for determining the relative positions of the jaw and the main body by echography and/or radiography.

25. The instrument according to claim 1, further comprising a fold-out structure equipped to fold out and to protrude, when folded out, radially-outward out of the cylindrical volume defined by the outer surface of the main body and jaw.

26. The instrument according to claim 25, wherein the fold-out structure is a fold-out support extending an area of at least one of the abutment surfaces.

27. A set, comprising an instrument according to claim 1, and further comprising an implant that has a proximal implant part, a distal implant part, and a chord connecting or equipped to connect the proximal implant part and the distal implant part.

28. A method of replacing or supplementing damaged natural chordae tendineae of a human or animal heart of a patient in need thereof, the method by using an instrument according claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0087] Hereinafter, principles and embodiments of the invention are described referring to drawings. Same reference numbers in the drawings refer to same or analogous elements. The drawings show:

[0088] FIG. 1: A schematic drawing of an instrument with a grabbing structure including a main body, a jaw and a counter portion.

[0089] FIG. 2: A schematic drawing of the instrument of FIG. 1, wherein the counter portion has been moved in axial direction towards the jaw.

[0090] FIG. 3: A schematic drawing of the instrument of FIG. 1, wherein the needle has been moved in axial direction through the jaw.

[0091] FIG. 4: A schematic drawing of an instrument according to the invention with a grabbing structure including a main body and a jaw.

[0092] FIG. 5: A schematic drawing of the instrument according to FIG. 4, wherein the view is changed.

[0093] FIG. 6: A schematic drawing of the instrument according to FIG. 4 in a closed configuration.

[0094] FIG. 7: A schematic drawing of the instrument according to FIG. 4, wherein the needle reaches through the jaw.

[0095] FIGS. 8A-8C: Schematic drawings of the instrument of FIG. 4 in open configuration in a perspective view with different orientations.

[0096] FIGS. 9A-9C: schematic drawings of an instrument according to the invention, wherein the first and second abutment surfaces define a plane being oblique to the tube axis.

[0097] FIGS. 10A and 10B: Two representations of a grabbing structure including support wires and lateral grooves for the attachment of marker stripes.

[0098] FIG. 11: A schematic drawing of a main body being part of an instrument according to the invention showing a lateral groove for a marker.

[0099] FIG. 12: A schematic drawing of a jaw being part of an instrument according to the invention showing a lateral groove for a marker.

[0100] FIGS. 13 and 14: A grabbing structure with antennae, in an open and a closed configuration;

[0101] FIGS. 15-17: A main body of an alternative grabbing structure and the grabbing structure in two different states, respectively;

[0102] FIGS. 18 and 19: Variants of the grabbing structure of FIGS. 15-17 with markers; and

[0103] FIGS. 20 and 21: A grabbing structure with wing-like fold-out structure, in a folded-in and a folded-out configuration, respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0104] The following more detailed description of the embodiments of the instrument is a representative of exemplary embodiments of the technology, wherein similar parts are designated by same numerals throughout. Standard medical planes of reference and descriptive terminology are employed in this specification. In particular, proximal means toward the trunk, or, in the case of an inanimate object, toward a user and distal means away from the trunk, or, in the case of an inanimate object, away from a user.

[0105] FIGS. 1 to 3 show one exemplary embodiment of a grabbing structure being part of an instrument for repairing an atrioventricular heart valve. FIG. 1 shows a grabbing structure 3 including a main body 4 and a jaw 5 in an open position. The grabbing structure may be formed as a bullet tip grasper (bullet tip grabber). The grabbing structure may have a length of 0.75 to 1.2 cm. The jaw may be formed as a distal nosecone tip able to be advanced over two guiding rails to create a grasping opening. As shown in FIG. 2, the main body includes a second abutment surface 7 formed by a press pad at the distal end of a counter portion 19 that is releasable from the main body as shown in FIG. 2. The press pad is movable in axial direction towards the jaw to grasp and hold a leaflet. As can be seen in FIG. 3, a cannulated needle 8 forming an inner tube 9 can be advanced from a proximal end of the grabbing structure (within a first tube which is not shown in FIGS. 1-3) through the main body, the counter portion and a channel within the jaw to protrude out of the grabbing structure. When the needle is advanced, it is able to puncture the grabbed leaflet. Within that needle, an implant may be arranged so that at least one part of the implant (distal implant part) may be implanted distally of the leaflet. The counter portion may be formed having a base being tube shaped or being elongated with an angular cross section and a channel for the cannulated needle. The press pad at the distal end of the counter portion may be round with at least one cut out to be sliceable on the guiding rails.

[0106] FIGS. 4 to 8 and 8A-8C show an exemplary embodiment of an instrument 1 according to the present invention. The instrument is shown in different perspective views. The proximal end of the main body 4 is attached to a first tube 2. The grabbing structure 3, the needle 8 and the implant can be manipulated via the first tube. This tube may be an implant catheter. For accessing the heart, the instrument may include a further, outer catheter (for example a transseptal and guide catheter) that is, for example, capable of being advanced through a suitable vein into the right atrium and from there into the left atrium, and from which the main body attached to the first tube 2 is deployed further into the left atrium to grab, together with the jaw, the leaflet. The tube may be a braided sheath with flexible section at the distal tip and a maneuvering section at the proximal end. For example, it may be a Pebax® Catheter including a distal flexible section provides appropriate column strength and stiffness. The first tube can provide depth translation through and with the transseptal and guide catheter providing trajectory alignment to the heart valve, such as a mitral valve. The first tube may further include at least one marker band, such as a platinum band.

[0107] In contrast to the structure shown in FIGS. 1-3, in the embodiment of FIGS. 4-8, 8A-8C and the embodiments described hereinafter, there is no separate counter portion capable of being advanced relative to the main body, but the main body 4 itself serves as the counter portion by including the distally facing second abutment surface 7.

[0108] The main body 4 can include a channel 20 for the cannulated needle 8 and a (central) guide wire channel 16 for a guide wire. The guide wire channel continues within the jaw 5 (see FIGS. 8 C and D; jaw guide wire channel portion 116 aligned with main body guide wire channel portion 16). The channel 20 for the cannulated needle is also continued within the jaw by the jaw portion 120 of the channel. This channel allows that the cannulated needle is advanced through the main body and the jaw and punctures the leaflet when held between the first and second abutment surfaces, and that one part of the implant can be released and implanted within a ventricle tissue (see hereinafter).

[0109] In the embodiment of FIGS. 4-8, 8A-8C, the channel, more specifically the jaw portion 120 of the channel, has a slit-like lateral opening 13. After implantation of at least the distal part of the implant this opening allows to release an artificial chord attached to the implant parts carried by the cannulated needle. After withdrawal of the needle, the artificial chord can be released from the grabbing structure by a lateral movement.

[0110] The grabbing structure includes a mechanism to move the jaw in relation to the main body in axial directions. The mechanism includes an operating structure such as an operating rod any may further include one or more guiding rods 15 (guiding rails).

[0111] In many embodiments, the operating structure is an operating rod (which can have a dimension to be bendable and therefore may be viewed as operating wire also), which is subject to axial movements from outside directly by the operator. Alternatively, as shown here, the movement may be facilitated by a threaded rod 14. In this alternative mechanism, the operator causes an axial movement by causing a rotation of the threaded rod. The embodiment with a threaded rod has the advantage of allowing a more precise determination of the axial position without the necessity of a feedback by means of monitoring but has the disadvantage that it may be sometimes difficult to transfer a rotational (torsional) movement across a comparably long distance of for example up to 1 m through the tubing.

[0112] Generally, while for illustration purposes most figures show an operating structure in the form of a threaded rod, a direct axial movement by an operating rod (operating wire) as well as an operating structure in the form of a threaded rod or other operating structures are options for all embodiments of the present invention.

[0113] The length of the grabbing structure in the open configuration may be 25-40 mm. Thereby the opening width is 8 to 15 mm, preferably 12 mm, the length of the main body is 10-20 mm and the jaw may have a length of 4-10 mm. The diameter of the grabbing structure may between 4.5 and 8 mm.

[0114] FIG. 6 shows the grabbing structure in a closed or nearly closed configuration. Between the second abutment surface 7 of the main body 4 and the first abutment surface 6 of the jaw 5 a leaflet can be clamped and held.

[0115] FIG. 7 shows the grabbing structure in a closed or nearly closed configuration and with a cannulated needle 8 advanced to protrude distally from the jaw 5. The cannulated needle has a sharpened distal end 17.

[0116] The first abutment surface 6 and the second abutment surface 7 define a plane. This plane and the tube axis form an angle of 90° in the embodiment shown in FIGS. 4-8, 8A-8C. In alternative embodiments, see also the embodiments described hereinafter, the angle may also be smaller.

[0117] As can be seen in FIGS. 8 A and B as well as in other figures, the first abutment surface 6 and/or second abutment surface 7 may be structured by having a surface structure 106, 107 forming a pattern of protrusions/indentations. Exemplarily, small pyramids having a square base are shown as the surface structures 106, 107. The surface structures 106, 107 may be formed to be complementary. This means that the structures fit to each other in case the grabbing structure is in a closed configuration. Therefore, the structures allow to increase the grip but in closed configuration there exists no risk for unwanted clamping of other structures than the leaflet because no open spaces are left between the main body 4 and the jaw 5.

[0118] FIGS. 9A-9C show another embodiment of a grabbing structure 3 being part of an instrument 1 according to the present invention.

[0119] A first difference between the hereinbefore described embodiments and the embodiment of FIGS. 9A-9C is that the abutment surfaces 6, 7—which are parallel to each other—are not at a right angle to the axis 10 but have at least a section that is not perpendicular thereto. Especially, in the embodiment of FIGS. 9A-9C, the abutment surfaces are not perpendicular to the axis at the position where the channel for the cannulated needle 8 goes through them.

[0120] In the specific depicted embodiment, the first abutment surface and the second abutment surface include each three portions. In closed position (FIG. 9A) the corresponding portions of these abutment surfaces thus define three planes. Two planes form with the tube axis an angle of 90° or nearly 90°. The plane defined by a middle portion connecting the perpendicular portion forms with the tube axis an angle β of for example between 25 and 80°, for example between 30° and 60°. The cannulated needle 8 is pushed through the abutment surfaces within this section defining the plane being oblique in relation to the tube axis.

[0121] Other shapes of the abutment surfaces other than perpendicular are possible, including locally curved surfaces.

[0122] One possible feature of embodiments having abutment surfaces that are not perpendicular to the axis is also illustrated in FIG. 9B. The plane 206 defined by the abutment surfaces in vicinity of the channel for the cannulated needle is non-parallel to the plane 117 defined by the distal end 17 of the needle 8. Thereby, when the needle pierces the grabbed leaflet, the distal needle end does not lie flat against the leaflet, but for example the tip pierces the leaflet first.

[0123] Especially, the middle plane 117 defined by the distal end may be inclined, with respect to the axis, in a direction different from the direction of inclination of the plane 206 defined by the abutment surfaces around the channel (being a middle plane of the mouth of the channel in the abutment surfaces) and, for example, inclined in approximately the opposed direction, as illustrated in the shown embodiment.

[0124] The cannulated needle 8 may include a laser cut section 18 proximal of the sharpened distal end. Such section includes a plurality of cuts in the otherwise cylindrical body, increases the flexibility of the needle and allows to implant one implant part within a ventricle tissue such as the ventricle wall or a papillary muscle. The laser cuts run on the circumference of the needle in form of an open ring. Thus, the cuts may have the form of circle arcs. It is preferred that the laser cuts in form of circle arcs are arranged alternating, so that the not cut part on each circle varies in position.

[0125] The cannulated needle 8 is shown to be in advanced position so that the distal end of the cannulated needle protrudes over the distal end of the jaw 5. Anchor carrier or implant carrier 11 is located within the needle and surrounded by an optional implant sleeve 12 or alternatively directly by the needle. The implant sleeve 12 and the implant carrier may be advanced to protrude distally from the needle. The implant carrier is designed to accommodate the implant parts. After the implant sleeve is withdrawn, the implant may be released. The implant carrier may have a lateral seat 61 at least for the proximal implant part. A portion distally thereof serves as foot portion 62 for preventing the proximal implant part from slipping out of the implant sleeve 12 as long as the proximal implant part is within the implant sleeve 12 (or, if there is no implant sleeve 12 within at least the cannulated needle 8).

[0126] The implant sleeve and the implant carrier may be made from nitinol and may also include a laser cut section, which may be formed in the same manner as the laser cut section of the cannulated needle.

[0127] An even further feature of the embodiment of FIGS. 9A-9C—which may independently of the other features described referring to these Figs be implemented in any embodiment—refers to markings. The main body 4 includes a groove 21 for a marker stripe and the jaw 5 a groove 22 for another marker stripe. The grooves may be located near the edge of the abutment surfaces and may be curved. In these grooves a stripe of a radiopaque material or of a material yielding a good contrast in echography (sonography) can be attached. For example, stripes of a platinum-iridium alloy can stick in these grooves. Such strips look under X-radiation like two hooks and allow to determine the orientation of the grabbing structure as well as if and to what extent the grabbing structure is open.

[0128] FIGS. 10A and 10B each show a representation of another embodiment of a grabbing structure 3 being part of an instrument according to the present invention. FIG. 10A shows the grabbing structure in closed form, and FIG. 10B depicts the same in an open position.

[0129] The grabbing structure in addition to the features described hereinbefore includes further a fold-out support, such as a wire support 23. A fold-out support or other fold-out structure is equipped to fold out and to protrude radially-outward out of the cylindrical volume defined by the outer surface of the main body and jaw, and for example out of the outer catheter (such as transseptal guide catheter). The fold-out structure may, for example, fold out automatically upon release from such outer catheter, upon the grabbing structure being opened and/or upon a trigger action induced by the operator.

[0130] A fold-out support enhances the effective area for cooperating with the leaflet and hence may facilitate grasping the leaflet. It may be folded out from the jaw or from the main body. It is also possible to combine these two options. Especially, to be able to support the leaflet, the wires may increase the area of at least one abutment surface.

[0131] In the depicted embodiment, the fold-out support is a wire support consisting of, for example, two wires. In the open position the wires support the grasped leaflet, and thus promote the grasping of the leaflet. The wire support can consist of one wire loop or of two wires attached in parallel. Such wires may be bent at the free end. A wire support of two wires is preferably arranged to include a gap between the two wires which is aligned with the recess 13 of the channel 120 so as to allow releasing the chord from the needle arrangement.

[0132] The wire support can be arranged in a way that it is closely attached to the grabbing structure in the closed position but can stick out in the open position. Therefore, the free ends of the wires attached to the jaw may be located in support recesses 123 within the main body. While the jaw moves away from the main body, the wires are pulled out and unfold or flip open. The wire supports may be made of a material having shape memory effect such as nitinol. Alternatively, the wires may be made of a material being radiopaque or contain radiopaque marker.

[0133] A further feature of the embodiment of FIGS. 10A and 10B as well as of embodiments described hereinafter—which further feature may be implemented independent of the other features of this embodiment—is the absence of a threaded rod for causing the axial movement of the jaw relative to the main body. Instead, one or both of the rods 15 that serve as guiding rods may be connected to a push-pull operating mechanism (essentially a push-pull wire) and thereby also serve for operating.

[0134] FIG. 11 shows a drawing of a main body 4 of a grabbing structure including a channel 16 for a guide wire and the channel 20 for a cannulated needle. Besides the abutment surface 7 the main body includes a groove 21. Within the groove 21 a radiopaque marker can be bond. There may be an analogous groove on the other side of the main body. The groove can be 3 to 8 mm long, 0.15 to 0.5 mm deep and has a width between 1.5 and 4 mm.

[0135] FIG. 12 shows a drawing of a jaw 5 of a grabbing structure, the jaw being equipped for cooperating with a main body as shown in FIG. 11. The jaw includes a channel for a cannulated needle, the channel having a recess 13 so that the channel is open to the top. Besides the abutment surface, the jaw includes a groove 22. Within the groove 21 a radiopaque marker can be bond. There may be an analogous groove on the other side of the jaw. The groove can be 3 to 8 mm long, 0.15 to 0.5 mm deep and has a width between 1.5 and 4 mm.

[0136] FIGS. 13 and 14 show a variant of the embodiments of FIGS. 9-12 in the closed condition and in the open condition of the grabbing structure, respectively. In contrast to the previously described embodiments, the grabbing structure includes a fold-out structure in the form of at least one fold-out antenna. In the embodiment of FIGS. 13 and 14, it includes two fold-out antennae, both attached laterally to the main body. The antennae increase, by radially protruding away from the main body and/or the jaw in the unfolded condition, the visibility when echography is applied. Much like a wire support of the above-described kind, such antenna can be arranged in a way that it is closely attached to the grabbing structure in the closed position but can stick out in the open position. Also, the free end of the antenna may be seated in an according recess, such as an antenna recess 151 in the jaw. When the grabbing structure is deployed from the outer catheter or when the jaw moves away from the main body, the antenna is folded out. Also, the antenna may be made of a material having shape memory effect such as nitinol and/or of a material being radiopaque or contain radiopaque marker.

[0137] In the embodiments of FIGS. 4-14 described hereinbefore, the channel for the cannulated needle is open towards a single lateral side by there being formed a slit-shaped recess in the jaw, whereas the—proximal—main body does not have such feature. For releasing the proximal implant part, the proximal implant part—for example carried by the anchor carrier as shown in FIGS. 9A-9C—has to be deployed from the main body. If the proximal implant part is to lie proximally of the leaflet, deployment, therefore, may be done after the leaflet has been released from the grabbing structure.

[0138] The embodiments of FIGS. 15-19 described hereinafter are equipped for the option of there being a proximal anchor release while the leaflet is still being grabbed. This makes additional control by the operator possible—i.e., both is possible: release of the proximal implant part while the leaflet is still being grabbed, or release of the proximal implant part after release of the leaflet.

[0139] To this end, not only the channel portion 120 in the jaw but also the main body channel portion 20 is open to a lateral side (i.e. the same side as the jaw channel portion) by the main body 4 having a recess 24 extending from the distal end. In the depicted embodiment, the recess has a narrow distal recess portion 25 and a broader proximal recess portion 26 serving as implant release portion. The length (axial extension) and width of the recess or, if present, of its implant release portion 26 are sufficient for the proximal implant part to be released therethrough. Especially, the opening angle α of the main body recess portion or of its implant release portion may be at least 45° or at least 60° or at least 80° or more. The length is larger than the length of the proximal implant portion and hence larger than the length of the anchor carrier seat 61.

[0140] In FIGS. 16 and 17 a further optional feature is illustrated. Namely, the cannulated needle 8 is encompassed by a needle guide tube 71. The needle guide tube encompasses the needle 8 essentially up to its distal end during the forward (towards distally) movement of the needle for piercing the leaflet while the leaflet is being clamped. The needle guide tube 71 is retracted thereafter for release of the proximal implant part. The needle guide tube 71 makes sure that the needle is guided towards and into the jaw channel portion even if the leaflet causes a mechanical resistance against the forward movement/puncturing and even though the proximal recess portion is relatively wide open.

[0141] FIGS. 18 and 19 illustrate possible positions of markings that may be used to make sure that the axial positions of the anchor carrier 11 and of the implant release portion 26 are properly adjusted for implant release even if the device is too flexible for the operator to be able to define the relative positions precisely enough for the deployment of the proximal anchor just from markings on the handle device. In FIG. 84, the main body 4 includes a circumferential (extending by 280° in the depicted embodiment) marker 84 the axial position of which defines an axial position of a central anchor carrier marker 85. According to a second option, a distal anchor carrier marker 86 may be aligned with the side markers 81, 82 of the main body 4 and/or the jaw 5, which are present in the marker grooves 21, 22 described hereinbefore.

[0142] The embodiment of FIGS. 20 and 21 includes a fold-out structure that is constituted by wing-like elements 160 capable of being folded out from the main body to assist orienting the grabbing structure with respect to the leaflet, especially by being visible by echography and/or radiography. Depending on the position and structure, a wing-like element may, in embodiments different from the one shown in FIGS. 20 and 21, also act to enhance the effective area for supporting the leaflet and thereby also work as fold-out support. In the folded-in condition (FIG. 20), the wing-like elements 160 are accommodated in a seat 161 so as to not protrude radially-outward out of the cylindrical volume defined by the outer surface of the main body and jaw, whereas in the folded-out condition (FIG. 21) they radially protrude outward of this cylindrical volume. The fold-out process may take place automatically upon the grabbing structure being released from the outer tube it is guided in.