Patent Publication Number: US-2020289258-A1

Title: Heart Valve Comprising A Crown Piece Interconnected To Leaflets, A Top Cuff And A Bottom Cuff; And A Medical Implant

Description:
The present invention relates to a heart valve according to claim  1  and to a medical implant (short hereinafter: implant) according to claim  7 . 
     From WO 2009/109348 A1, implants comprising a frame and a heart valve attached to the frame are known. 
     One object of the present invention is to provide another heart valve and another medical implant comprising such a heart valve. 
     This object may be solved by a heart valve having the features of claim  1 . Insofar as the terms “invention” and/or “embodiment” are used in the following, and/or features are presented as being optional, this should be interpreted in such a way that the only protection sought is that of the invention as claimed. 
     According to the present invention, a heart valve is suggested which comprises at least two heart valve leaflets. It also comprises at least one crown piece (also referred to as ‘triangle’ hereinafter) interconnected to the leaflets. The crown piece is preferably intended to be interconnected, directly or indirectly, for example sewed, to a frame (also referred to as the support or the body of the implant or a stent by way of example hereinafter). 
     The heart valve further comprises a top cuff and a bottom cuff. 
     The crown piece, the top cuff and the bottom cuff are each rings or ring-shaped, and both the top cuff and the bottom cuff are interconnected with the crown piece. 
     Also, according to the present invention, a medical implant comprising a heart valve according to the present invention is suggested. The implant has a frame or support or stent that is foldable and/or unfoldable. 
     The frame comprises at least or exactly one first guiding structure for guiding or comprising at least one tension thread for folding and/or unfolding the frame around or along the frame, for example at an outside or an circumference thereof. 
     The frame comprises at least or exactly one second guiding structure different from the first guiding structure also for guiding or comprising at least one tension thread for folding and/or unfolding the implant around or along the frame, for example at an outside or an circumference thereof. 
     The frame further comprises at least two, preferably three, posts. The posts are arranged between the first and the second guiding structure such that they interconnect the first and the second guiding structure with each other and/or maintain the distance between them. 
     In the following, the use of the expression “may be” or “may have”, and so on, is to be understood synonymously with “in exemplary embodiments is” or “in exemplary embodiments has”, respectively, and so on, and is intended to illustrate exemplary embodiments according to the present invention. 
     Exemplary embodiments according to the present invention are each also subject of dependent claims. 
     Exemplary embodiments according to the present invention may comprise one or more of the features named hereinafter. 
     In certain exemplary embodiments according to the present invention, the implant may be folded or unfolded upon implantation by using one or several tension threads or filaments wound around the implant. 
     In particular exemplary embodiments according to the present invention, the crown piece is foldable and unfoldable. 
     In certain exemplary embodiments according to the present invention, the crown piece does not comprise a threading, particular exemplary embodiments according to the present invention, the frame of the heart valve does not comprise threading either. 
     In particular exemplary embodiments according to the present invention, a foldable and/or unfoldable frame or support or stent is a structure that can unfold from a crimped state to an unfolded state, for example because of its, optionally provided, shape memory material. 
     In some exemplary embodiments according to the present invention, altering the shape of the implant means reducing or increasing a diameter, particularly an external diameter, of the implant. Such an alteration may or may not involve an alteration of the implant&#39;s length or any other kind of alteration. 
     In certain exemplary embodiments according to the present invention, folding the implant means reducing the diameter of the implant. Folding also covers “re-folding” of an once expanded implant. 
     In some exemplary embodiments according to the present invention, unfolding should be understood as increasing the diameter of the implant, or as expanding. 
     In certain exemplary embodiments according to the present invention, the diameter of the implant is arranged in a plane perpendicular to a main flow direction of the implant in case fluids flow through the implant after its implantation. 
     In some exemplary embodiments according to the present invention, at least one of the top cuff and the bottom cuff is formed from a stripe (or strap) or comprises a stripe (or strap, e.g. a thin band that is longer than broad). The stripe is (in its flat state) curved along its length, preferably or at least in a plane of its width. 
     In certain exemplary embodiments according to the present invention, the top cuff has a width that is smaller than a width of the bottom cuff. 
     In certain exemplary embodiments according to the present invention, the ‘width’ refers to an average width of the stripe. 
     In some exemplary embodiments according to the present invention, the top cuff and the bottom cuff are equally long (or almost equally long). 
     In particular exemplary embodiments according to the present invention, the top cuff is arranged closer to the leaflets than the bottom cuff. 
     In some exemplary embodiments according to the present invention, all leaflets are sewed to the crown piece by means of one or exactly one suture or stitch. 
     In particular exemplary embodiments according to the present invention, a suture is a filament or a thread or yarn. In these embodiments, One suture&#39; means one filament (or thread or yarn) used for sewing two pieces together. In these embodiments, no second filament is used and, in consequence, only one knot is required. 
     In some exemplary embodiments according to the present invention, both the top cuff and the bottom cuff are sewed to the crown piece by means of one or exactly one suture. 
     In particular exemplary embodiments according to the present invention, the crown piece is sewed to the posts, preferably using (or via or through) through holes or eyelets of the posts, preferably through at least three or four, preferably consecutive through holes, preferably by means of tabs being small extensions of the crown piece or by leaving out the tabs, preferably by means of one or exactly one suture per post. 
     In some exemplary embodiments according to the present invention, the suture for interconnecting the crown piece to one post was started from an outer side of that post to an inner side of the post. Preferably, the single knot that interconnects both ends of the suture is arranged on an outside of the post. 
     In particular exemplary embodiments according to the present invention, the posts are arranged inside a circle or an area circumscribed by the crown piece. 
     In some exemplary embodiments according to the present invention, the posts are arranged outside the circle or the area circumscribed by at least one of the top cuff and the bottom cuff. 
     In particular exemplary embodiments according to the present invention, at least one of the first and the second guiding structure comprises or consists of bars (can be struts instead) that are interconnected to each other so as to form a zig-zag pattern or an undulating or meandering pattern. Neighbouring or adjacent or contacting bars are provided for moving relative to each other or for changing a distance or an angle between them (or between sections thereof, respectively) upon folding or unfolding of the implant or frame. The bars are preferably arranged outside the circle or the area circumscribed by at least one of the top cuff and the bottom cuff. In preferred embodiments according to the present invention the bars are covered on their inner side (being the side towards the inner space of the frame or implant) at least in part (s) by at least one of the top cuff and the bottom cuff. 
     In some exemplary embodiments according to the present invention, the leaflets have a first tab and a second tab arranged at opposite ends of the respective leaflet. The tabs are sewed onto the post of the frame. 
     In certain exemplary embodiments according to the present invention, the tabs extend from the body of the leaflet. 
     In particular exemplary embodiments according to the present invention, tabs of two adjacent leaflets are sewed to one post in an overlapping manner. 
     In certain exemplary embodiments according to the present invention, the tab of a first leaflet is or was sewed onto a post first, and wherein the tab of a second leaflet was sewed onto both the tab of a first leaflet and the post the tab of the first leaflet had been sewed to, all in one running stitch or with one suture. 
     In some exemplary embodiments according to the present invention, the medical implant comprises exactly three posts. 
     In certain exemplary embodiments according to the present invention, the heart valve comprises exactly three leaflets. In particular exemplary embodiments according to the present invention, the implant is a heart or cardiac valve assembly. 
     In certain exemplary embodiments according to the present invention, the crown piece may have up to three sections that are triangle in shape (at least once the crown piece&#39;s free ends are put together such that the crown piece forms a ring). 
     In particular exemplary embodiments according to the present invention, the frame (or support or body) of the implant is made of or comprises a metal or a shape memory material, such as, for example, Nitinol. 
     In certain exemplary embodiments according to the present invention, the top cuff and the bottom cuff are originally separate pieces, directly or indirectly interconnected with each other by sewing. 
     In some exemplary embodiments according to the present invention, the crown piece may have sections ending in a tip of a triangle section of the crown piece or in a tab extending from the tip of the triangle, the tab having a free end (before being fixed to, for example, the leaflets). 
     In certain exemplary embodiments according to the present invention, the crown piece is interposed between the top cuff and the bottom cuff. 
     In certain exemplary embodiments according to the present invention, at least one of the top cuff and the bottom cuff is made from porcine pericardium or is a fabric. 
     In some exemplary embodiments according to the present invention, the leaflets are interconnected with, preferably glued or sewed to, the crown piece. 
     In some exemplary embodiments of the apparatus according to the present invention, the at least one tension thread is a thread. The thread may be a surgical suture thread or similar to it. The thread may have the shape of a rope, a filament or a cord. The thread may be designed as a chain having a plurality of engaging chain links. 
     In this specification, the term thread or tension thread may also define a plurality of threads or tension threads whenever a person skilled in the art recognizes the exchangeability of the terms. 
     In certain exemplary embodiments according to the present invention, the implant or its frame is permeable for fluids in its implanted state in its longitudinal direction. “Permeable” means that the fluid may flow through the implant, for example, through an inner lumen thereof. 
     In particular exemplary embodiments according to the present invention, the frame has features as described in WO 2011/063972 A1 or WO 2009/109348 A1 with respect to the implant. 
     In certain exemplary embodiments according to the present invention, the implant is configured to have or has tension applied to it by using at least one tension thread. The tension is preferably controlled by altering a length of the pulling device by which it extends out of the interior of the shaft or a catheter or sections thereof. 
     In some exemplary embodiments according to the present invention, at least one of the heart valve and the frame comprises exclusively, i.e. only, (one or more) materials that are MRI (short for: magnetic resonance imaging) compatible. 
     In certain exemplary embodiments according to the present invention, at least one of the heart valve and the frame comprises exclusively (one or more) materials that are not magnetic, ferromagnetic, or both. 
     In some exemplary embodiments according to the present invention, at least one of the heart valve and the frame does not comprise metal or any metal alloy. 
     In certain embodiments according to the present invention, eat least one of the posts has at least two openings through which tension threads are guided from an inside or inner space of the implant to an outside of the implant and back from the outside to the inside. The tension threads are guided to the outside through a first opening of a first one of the posts and back to the inside—or vice versa—through any second first opening of any second post, the first opening being different from the second opening, and the first post being different from the second post. 
     In particular exemplary embodiments according to the present invention, the crown piece is interconnected to the frame of a medical implant or a heart valve assembly. 
     In certain exemplary embodiments according to the present invention, both the top cuff and the bottom cuff are interconnected to bars of a guiding structure of the frame, preferably by sewing, preferably in direct contact to the bars. 
     Some or all advantages achievable by the heart valve according to the present invention may in certain exemplary embodiments of the present invention also be achieved by medical implant according to the present invention. 
     Some or all exemplary embodiments according to the present invention may provide for one, several or all of the advantages named above and/or hereafter. 
     According to the present invention, the top cuff and the bottom cuff may have different widths. If the top cuff and the bottom cuff is now everted to the outside face of the bars both at an upper end and an lower end of the bars by an equal distance (the equal distance is usually equal since it takes the same amount of material or overlap to secure the cuffs on the tips of both the upper parts and the lower parts of the bars), a suture interconnecting the two cuffs (plus the crown piece) will not be positioned in a middle line of the bars. That way, the suture will not be damaged by the bars in a folded state of the implant in which the middle of the bars will usually have to face the highest pressure. At the same token, the suture does not contribute to applying pressure on the leaflets starting about the height of the bars of the guiding structure as the suture will not contribute to narrowing the space about the middle line of the bars due to its position beyond the middle line. 
     Further, sewing parts by just one suture may contribute in avoiding knots which in turn require space and are prone to damaging neighboring structures such as leaflets. 
     If, as in particular embodiments according to the present invention, the inner side of the top cuff is interconnected to the outer side of the bottom cuff, the resulting geometrical shape will show a profile that extends with a middle portion thereof into the inner space it circumscribes. In a front cut the geometrical shape may be called concave. That shape may fit best to the also concave shape of the bent bars and the resulting concave shape of the guiding structure which is another advantage. 
     Providing at least one of the heart valve and the implant to be MRI compatible allows advantageously for controlling the location and orientation of the apparatus or the implant, or both, by MRI upon use of the apparatus or implantation of the implant. No heat, sparks or artefacts are generated during MRI because of the materials chosen for the apparatus or the implant. 
    
    
     
       In the following, examples of the present invention will be described with reference to the accompanying figures wherein similar or identical assemblies or elements are denoted by same reference numerals. 
         FIG. 1 a    shows three leaflets of a heart valve according to a first exemplary embodiment of the present invention; 
         FIG. 1 b    shows a crown piece of a heart valve according to the first exemplary embodiment of the present invention; 
         FIG. 1 c    shows a top cuff of a heart valve according to the first exemplary embodiment of the present invention; 
         FIG. 1 d    shows a bottom cuff of a heart valve according to the first exemplary embodiment of the present invention; 
         FIG. 1 e    shows three pledges of a heart valve according to the first exemplary embodiment of the present invention; 
         FIG. 2  shows a medical implant according to the present invention in an expanded state which is expandable and can be reduced in its diameter by use of a means; 
         FIG. 3  shows the medical implant of  FIG. 2  in a non- or less expanded state; 
         FIGS. 4 a -4 c    show how the heart valve of  FIGS. 1 a  to 1 e    is being fixed or secured to a frame according to  FIG. 2 or 3 ; 
         FIGS. 5 a -5 c    show how tabs of adjacent leaflets of the heart valve according one embodiment of the present invention are commonly attached to one post of the frame; 
         FIGS. 6 a -6 c    show how a pledge is used for reinforcing the connection of the heart valve according to the frame of the present invention; and 
         FIGS. 7 a -7 b    show a top cuff and a bottom cuff sewed to the crown piece. 
     
    
    
       FIG. 1 a    through  FIG. 1 e    show parts of a heart valve  100  according to a first exemplary embodiment of the present invention. 
       FIG. 1 a    shows three leaflets  101 ,  101 ′ and  101 ″ of the heart valve  100  of the first exemplary embodiment of the present invention. Instead of three leaflets  101 ,  101 ′ and  101 ″ the heart valve  100  according to the present invention may comprise any other number of leaflets, for example two. In the exemplary embodiment of  FIG. 1 a   , all leaflets  101 ,  101 ′ and  101 ″ are identical. In other embodiments according to the present invention, at least two of them may, however, be different from each other. 
     In the exemplary embodiment of  FIG. 1 a   , each leaflet  101 ,  101 ′,  101 ″ has a body  103 ,  103 ′,  103 ″, respectively, having a round or curved bottom section  103   a ,  103   a ′,  103 ′ and a rim section  103   b ,  103   b ′,  103   b ″ opposing the corresponding curved section  103   a ,  103   a ′ or  103   a ″. The rim section  103   b ,  103   b ′,  103   b ″ extends into opposing tabs  103   c ,  103   c ′,  103 ″ and  103   d ,  103   d ′,  103   d ″ which form the outmost portions to the opposing sides of the respective body  103 ,  103 ′ or  103 ″ (i. e. left and to the right of in the illustration of  FIG. 1 a   ). 
       FIG. 1 b    shows a crown piece  111  of the heart valve  100 . In use, the crown piece  111  is formed to a ring by connecting together the free ends  111   a  and  111   b  of the stripe shown in  FIG. 1 b    with each other. 
     The crown piece  111  optionally comprises small tabs  113 ,  113 ′,  113 ″ and round portions  115 ,  115 ′  115 ″. The tabs  113 ,  113 ′,  113 ″ may be arranged between neighboring round portions  115 ,  115 ′  115 ″, respectively, or each. 
     The round portions  115 ,  115 ′  115 ″are shaped such that their curved rims correspond to the curved sections  103   a ,  103   a ′ or  103   a ″ of the leaflets  101 ,  101 ′,  101 ″. 
     In  FIG. 1 b   , the reference number  113 ″ is used twice. In practice, both small (half-) tabs  113 ″ will contact each other so as to form one single small tab afterwards. 
     In certain embodiments according to the present invention, the leaflets  101 ,  101 ′ and  101 ″ and/or the crown piece  111  (and, if applicable, also the pledges (also referred to a pledgets, these terms being, hence, synonyms)  141 ,  141 ′,  141 ″, see  FIG. 1 e   ) are cut (e. g. laser cut) from a (e. g. jib-fixed) bovine pericardium having a preferred thickness between 0.35 and 0.55 mm. 
     In some embodiments according to the present invention, the leaflets  101 ,  101 ′ and  101 ″are all of identical or similar stiffness. 
       FIG. 1 c    shows a top cuff  121  of the heart valve  100 . As can be seen from  FIG. 1 c   , the top cuff  121 , which is used in a ring-shaped form after having united the top cuffs ends  121   a  and  121   b  with each other, is formed from a flat stripe. The same applies to a bottom cuff  131  discussed below with reference to  FIG. 1 d    showing a bottom cuff  131  with ends  131   a ,  131   b  of the heart valve  100  according to the first exemplary embodiment of the present invention. 
     The width of the top cuff  121  is denoted with wtc. The width of the bottom cuff  131  is denoted with wbc. In certain embodiments according to the present invention, wtc is smaller than wbc. 
     The length of the top cuff  121  is denoted with 1. The length of the bottom cuff  131  is denoted with 1 as well since in the exemplary embodiment shown in the figures the top cuff  121  and the bottom cuff  131  are of the same length, at least with respect to a first side  121   c  of the top cuff  121  and a second side  131   c  of the bottom cuff  131 . “ 1 ” also denotes the length of the lower rim or side  111   c  of crown piece  111 . All lengths denoted with 1 are identical in certain embodiments according to the present invention. 
     The reference numerals rtc and rbc of  FIGS. 1 c  and 1 d    denote the radius of the curvature of the top cuff  121  and the bottom cuff  131 , respectively. The radius rtc and the radius rbc indicate that the stripes shown in  FIGS. 1 c  and 1 d    are not straight but bent within the drawing plane of  FIGS. 1 c  and 1 d   . rtc and rbc may be identical, without being limited hereto. 
     The inner side of top cuff  121  is denoted with  121   c , the outer side with  121   d.    
     The inner side of bottom cuff  131  is denoted with  131   c , the outer side with  131   d.    
     Because of the radius of top cuff  121  and bottom cuff  131 , their inner sides  121   c ,  131   c  are shorter than their outer sides  121   d ,  131   d , respectively. 
     In particular embodiments according to the present invention, the inner side  121   c  of top cuff  121  is interconnected with the outer side  131   d  of bottom cuff  131 . This way, the resulting structure will be generally cylindrical with a middle (or about middle) portion that protrudes into the inner space formed by the resulting structure. 
     In certain embodiments according to the present invention, top cuff  121  and the bottom cuff  131  are cut (e. g. laser cut) from a (e. g. surface-tension) porcine pericardium having a preferred thickness between 0.15 and 0.25 mm. 
     The small tabs  113 ,  113 ′,  113 ″ may be used fora temporary stitch for temporarily securing the crown piece  111  to the frame  1 . Both the provided temporary stitch and the small tabs  113 ,  113 ′,  113 ″ may be cut off and disposed later on. 
       FIG. 1 e    shows three pledges  141 ,  141 ′ and  141 ″ of the heart valve  100  according to the first exemplary embodiment of the present invention. The pledges  141 ,  141 ′ and  141 ″ are optional. The benefit of the potential pledges  141 ,  141 ′ and  141 ″ are discussed with regards to  FIGS. 6 a  to 6 c   . The number of the pledges may correspond to the number of posts  3 . 
     The medical implant according to some embodiments of the present invention comprises a heart valve  100 , for example the one discussed with reference to  FIGS. 1 a  to 1 d    or  1   e  and a frame  1  or supporting structure, for example the one discussed with reference to  FIGS. 2 and 3 . In certain embodiments according to the present invention, the medical implant consists of the heart valve  100  and the frame  1 . 
       FIG. 2  shows a frame  1  of an exemplary implant according to the present invention. The frame  1  is expandable and can be reduced again in its diameter. The diameter refers to a plane perpendicular to a longitudinal axis of the frame  1 . The longitudinal direction also corresponds to the direction of the extension of the catheter  6  shown in  FIG. 2 . 
     Frame  1  comprises at least a first or upper—preferably circular—guiding structure or ring  2   a  and a second or lower—preferably also circular—guiding structure  2   b . The guiding structures  2   a ,  2   b  are connected to rods or posts  3 . In some embodiments, the guiding structures  2   a ,  2   b  can—additionally or alternatively or exclusively—fulfill the function of guiding structures for reins  5 . The reins  5  form part of a catheter  6  and serve for applying force or tension or stress, respectively, to the guiding structures  2   a ,  2   b  for the purpose of expanding or folding the frame  1  in a targeted manner. In the example of  FIG. 2 , the guiding structures  2   a ,  2   b  are each designed having the shape of an outwardly half-open channel through which the reins  5  are guided. The half-open channel is opened in a direction away from the centre of the frame  1 . However, the channel can also be shaped to be open to the implant or to any other direction. 
     In the example of  FIG. 2 , the guiding structures  2   a ,  2   b  are interrupted by posts  3 , i.e. the posts  3  are integrated into the guiding structures  2   a ,  2   b  such that they form sections of the guiding structures  2   a ,  2   b.    
     In the embodiment of the frame  1  according to the invention shown in  FIG. 2 , the posts  3  and/or the guiding structures  2   a ,  2   b  have (round or differently shaped, e. g., oval, rectangular, elliptic, and so on) passage means or apertures  10 . In the embodiment shown in  FIG. 2 , they serve as a passage for the reins  5 . The posts  3  also have through openings  8 , for example eyelets, which can be arranged in two parallel rows as in  FIG. 2 , in one row as in  FIGS. 4 a  to 4 c   , or in any other arrangement. 
     Furthermore, the frame  1  can also comprise a number of guiding means  2   a ,  2   b  other than two, for example, one, three, four or more guiding means. 
     The guiding structures  2   a ,  2   b  can be arranged circularly, however, they can also be arranged non-circularly. 
     The guiding structures  2   a ,  2   b  can be formed integrally with the implant; however, they can also be fabricated separately. 
     The guiding structures  2   a ,  2   b  can have the shape of a wave or undulation, respectively; however, they can also be fabricated in any other form, in particular, a non-wavy or non-undulating form. 
     Independent of all other features, frame  1  or parts thereof can be fabricated from flat material, e. g., a material which has been cut with a laser, wherein, e. g., after having designed a pattern in the flat material, the material is reformed into a tube (optionally by connecting, such as welding, longitudinal sides of the former flat material lane or web, respectively). However, frame  1  can also be fabricated from a tubular material directly. 
     The guiding structures  2   a ,  2   b  of frame  1  comprise or consist of a plurality of bars  11  which are each connected to another by means of connecting sections  9 . The plurality of bars  11  may be arranged in a zig-zag pattern or an undulating or meandering pattern as is exemplary shown in  FIG. 2 . 
       FIG. 3  shows the frame  1  of  FIG. 2 . Two reins  5  have been led or guided around the frame  1  and return back to the catheter  6  through the respectively same passage means or apertures  10 . The reins  5  apply a tension or stress on the frame  1 , and, in consequence, frame  1  is not completely expanded or unfolded. Rather, the diameter of the frame  1  has been reduced or is being hindered from expanding in a free manner. 
     At least one of the top cuff  121  and the bottom cuff  131  can be secured to the bars  11  of the second or lower guiding structure  2   b , for example by using a whip stitch, with, e. g. four stitches per bar  11 , preferably evenly spaced. At some or all of the top portions of bars  11 , indicated by  2   b ′ in  FIG. 2  and  FIG. 3 , and/or at some of all of the bottom portions of the bars  11 , indicated by  2   b ″ in  FIG. 2  and  FIG. 3 , the curved bottom sections  103   a ,  103   a ′,  103   a ″ of the leaflets  101 ,  101 ′,  101 ″ are additionally secured to the frame  1 , for example once again by means of one or more surgeon&#39;s knots. Care should be taken to secured the body  103   a ,  103   a ′,  103   a ″ only at its rim or seam section. 
       FIGS. 4 a -4 c    show how the heart valve  100  of  FIGS. 1 a  to 1 d    or  1   e  is being fixed or secured to an exemplary post  3  of a frame  1  according to  FIG. 2 or 3  in temporal subsequence. 
     As can be seen in  FIG. 4 a   , a suture  201  is pierced through the crown piece  111  and then let through a through hole  8  of the post  3 . In doing so, the suture is guided from the outside of the heart valve  100  to the inside of the heart valve  100 , leaving a suture tail of at least 2 cm on the outside of the heart valve  100 . This tail will later be used to make a knot. Next, a running stitch is created down the post  3  going in and out of the through holes  8  (eyelets) until the suture has been guided through four (preferably neighbouring) through holes  8 . The suture is then returned back up the post  3  in and out of the through holes  8  until the through hole  8  below the suture tail is reached, see  FIG. 4 b   . The suture is tied off using the starting suture tail using a surgeon&#39;s knot  203  or any other knot or fixture. The knot  203  should be on the outside of the heart valve  100  and/or on an outer side  3   o  of the post  3  as in  FIG. 4   c.    
       FIGS. 5 a  to 5 c    show how a tab  103   c  and a tab  103   d ′ of adjacent leaflets  101  and  101 ′ are attached to a common post  3  of the frame  1 . 
     As can be seen from  FIG. 5 a   , tab  103   c  of leaflet  101  is folded over onto the body  103  of leaflet  101 , and a knot  161  is created at the top of tab  103   d ′. Knot  161  secures the heart valve  100  in place on the frame  1 . A suture tail  163  of the suture is not cut. With a running stitch  165  going in and out of preferably each eyelet  8  downwards on the tab  103   d ′ which is placed on an outside of the post  3  the tab  103   d ′ is secured more and more to the post  3  until the bottom of tab  103   d ′ is reached. 
     Now, as is shown in  FIG. 5 b   , tab  103   c  is folded back over tab  103   d ′ (and hence also on an outside of post  3  although not in contact with the post  3 ) and the stitch  165  is continued back up the tabs  103   c  and  103   d ′, again while going in and out of the eyelets  8  until the top of the tabs is reached. 
     Tail  163  is used for tying off using a suitable knot such as a surgeon&#39;s knot  167 , see  FIG. 5   c.    
       FIGS. 6 a  to 6 c    show how one of optional pledges  141 ,  141 ′,  141 ″ as described above is used for reinforcing the connection of the heart valve  100  to the frame  1 . 
       FIGS. 6 a  to 6 c    show a post  3  having an outside face  3   o  and an inside face  3   i . Outside face  3   o  is directed to an outside of frame  1  whereas inside face  3   i  is directed to an inside of frame  1 . 
     A section of post  3  which is enwrapped by a leaflet  101  is now also enwrapped by a pledge  141  such that the free ends of pledge  141  are put above each other or superposed (only separated from each other by the leaflet  101  arranged between the free ends of the pledge  141 ) in a inner space of frame  1 , i. e. at the inside face  3   i  of post  3 . 
     Starting from the top of pledge  141 , a running stitch  171  is run down to the bottom of the pledge (see  FIG. 6 a   ) and then back up to the top (see  FIG. 6 b   ). A knot  173  is made using the beginning suture&#39;s tail (see  FIG. 6 c   ). Preferably, the knot  173  is on the side of the pledge  141  and does not contact the leaflet  101 . 
       FIGS. 7 a    shows the top cuff  121  and the bottom cuff  131  before being interconnected, e. g. sewed, to the crown piece  111 , in an exploded view. 
     If sewed, the arrow indicates the direction of how a first stitch of a suture  211  (see  FIG. 7 b   ) may be made. 
     As can be seen from  FIG. 7 a   , the crown piece  111  may be posed between the top cuff  121  and the bottom cuff  131 . 
     Also, the three elements  111 ,  121 ,  131  may be interconnected such that an end of the inner rim or side  121   c  of the top cuff  121  and an end of the lower rim or side  111   c  of the crown piece  111  are aligned at one side (see the right hand side in  FIG. 7 a   ) such that they end on a common level, whereas an end of the inner rim or side  131   c  of the bottom cuff  131 , which extends remarkably beyond the ends of inner rim  121   c  and lower side  111   c  to the right in  FIG. 7 a   , is not aligned with the ends of the lower rim or side  111   c  and the inner side  121   c.    
       FIG. 7 b    shows the elements of  FIG. 7 a    interconnected with each other, here by means of an exemplary suture, denoted by reference numeral  211 . As mentioned above with respect to certain exemplary embodiments according to the present invention suture  211  may run along the entire length  1  (see  FIGS. 1 b  to 1 d   ). Suture  211  may be the sole or only suture used for interconnecting these three elements. 
     Both the top cuff  121  and the bottom cuff  131  are bend upwards (with regards to  FIG. 7 b   ) to assume a c-shape which is open towards the top of  FIG. 7 b   . The c-shape is very similar to the shape bars  11  assume in  FIG. 2 . Hence, the c-shape is well-suited if the combination of top cuff  121  and bottom cuff  131  is to cover bars  11  in practice from in inner side of the guiding structure  2   a ,  2   b  shown in  FIG. 2 . 
     The expansion of frame  1  may benefit or result from, in the present exemplary embodiment, from the internal stress or from shape-memory capacities of frame  1 . The frame  1  may be manufactured from Nitinol or comprise such material. 
     REFERENCE NUMERALS 
     
         
           1  frame 
           2   a  first or upper guiding structure  2   b  second or lower guiding structure  2   b ′ top portion of the bars 
           2   b ″ bottom portion of the bars 
           3  posts 
           3   i  inside face of post  3   
           3   o  outside face of post  3   
           5  reins or tension thread(s) 
           6  catheter 
           8  through opening (s) or, as in particular embodiments; eyelet (s) 
           9  connecting sections 
           10  apertures 
           11  bars 
           100  heart valve 
           101 ,  101 ′,  101 ″ leaflets 
           103  body of the heart valve  100   
           103   a  curved bottom section 
           103   b  rim section of the body of the leaflet 
           103   c ,  103   d  opposing tabs 
           111  crown piece 
           111   a ,  111   b  free end 
           111   c  lower rim or side of the crown piece 
           111   e  end of the lower rim or side of the crown piece 
           113 ,  113 ′,  113 ″ small tabs 
           115 ,  115 ′  115 ″ round portions 
           121  top cuff 
           121   a ,  121   b  ends of top cuff 
           121   c  inner rim or side of top cuff 
           121   d  outer rim or side of top cuff 
           121   e  end of the inner rim or side of top cuff 
           131  bottom cuff 
           131   a ,  1316   b  ends of bottom cuff 
           131   c  inner rim or side of bottom cuff 
           131   d  outer rim or side of bottom cuff 
           131   e  end of the inner rim or side of bottom cuff 
           141 ,  141 ′,  141 ″ pledges 
           161  knot 
           163  suture tail 
           165  running stitch or suture 
           167  knot 
           173  knot 
           201  suture between crown piece and through hole 
           203  knot 
           211  suture interconnecting both the top cuff and the bottom cuff to the crown piece 
         l length of the stripe 
         rtc radius 
         rbc radius 
         wtc width of top cuff 
         wbc width of bottom cuff cm  1 - 16 . (canceled)