The object of the invention is a formable balloon for a heart valve and a method for its manufacturing, a balloon endovascular system comprising such a formed balloon dedicated to a heart valve and a set comprising the balloon endovascular system with the formable balloon and a valve.

More specifically, the invention relates to the field of endovascular procedures of replacing a native heart valve with a replacement valve, which comprises a specially designed balloon-expandable support frame, on which valve cusps and a sealing flange are seated, and the whole valve, i.e. a system of the frame with the valve cusps, is implanted using an endovascular system comprising elements known in this field and a specifically designed balloon, on which the valve is clamped in order to be delivered to the target location in the patient’s body. The introduction of the system along with the valve takes place by way of minimally invasive percutaneous methods.

Currently, there is a shift away from invasive surgical heart valve replacement procedures, and minimally invasive endovascular methods are being perfected as faster, safer, not requiring the use of general anaesthesia and shortening the period of convalescence. In addition, criteria for the selection of patients for minimally invasive methods are much gentler than those used for surgical procedures. For this reason, these methods can be used for patients unsuitable for surgical procedures due to extensive risk.

The invention relates to the procedures of implantation of a balloon-expandable valve, and thus a system for the implantation of such a valve comprises a flexible balloon which has a folded position with a minimum size, i.e. a smaller diameter, and an unfolded position with a larger diameter, when the balloon is being inflated during the valve implantation procedure. When the balloon is expanding to an inflated position, the valve takes on its desired unfolded shape.

From European application EP1057460A1 there is a known endovascular system for the implantation of a replacement valve, the system comprising an inflatable balloon, cylindrical in its middle part and conical on both ends, on which a cylindrical support body of the valve is placed, seated in its target location by inflating and subsequently deflating the balloon, when the valve is already in its fixed position.

From international patent applications W02008011261 A2, W02011106354A1 and WO2017053138A1 there are known endovascular systems for the implantation of a balloon-expandable valve, wherein the system can comprise a balloon with various target shapes took on upon inflation, so that the individual sections of the balloon are not always cylindrical, or the individual parts of the balloon have various diameters, or a part of the balloon is pear-shaped and a part is cylindrical. In its compressed (folded) position, the balloon exhibits no particular shape, but it is uniformly folded.

From international patent application WO2013096553A1 there is a known endovascular system for the implantation of a heart valve, comprising an inflatable balloon which comprises a middle part, a distal part and a proximal part, these parts being able to be susceptible to inflation in various ways and, as a consequence, the target shape, achieved upon inflating, comprising a constriction in its central part, so that wider segments delimiting the middle constriction are formed on both the distal and the proximal end. The abovementioned shape of the balloon is only achieved upon its inflation, and in its folded state the balloon exhibits no particular shape.

Balloons included in the abovementioned systems for the implantation of a heart valve have a modified shape, not visible until inflating the balloon, so that the performed valve implantation procedure would take into account the variable shape of the tissue surrounding a replacement valve, as well as for the replacement valve to be maintained stable in the final balloon inflation stage on a properly shaped balloon, in the target position, up until the end of the implantation process.

From the description of Polish patent application P.430463, submitted by the applicant of the present invention, there is a known design of a heart valve support frame. The endovascular system and set according to the present invention preferably comprise a heart valve made on the basis of the valve frame described in application P.430463.

The object of the invention is a formable balloon for a heart valve, having a folded form with a smaller diameter of its cross-section and an inflated form with a larger diameter of its cross-section, characterised in that in the folded form, in the area of the middle part, the balloon comprises a constriction delimited from the distal side and the proximal side by bulges. Preferably, the length n of the constriction is smaller or equal to the length l of the middle part of the balloon, and the bulges delimiting the constriction have the same or different shapes and/or sizes.

The object of the invention is also a method for manufacturing a formable balloon for a valve, characterised in that a folded balloon is placed in a closed space of a mould having within this space a constriction and bulges delimiting it, the mould is heated up along with the balloon; subsequently, a pressure differential is applied between the pressure inside the balloon and the pressure inside the mould to achieve adhesion of the balloon material to the mould walls, giving the balloon a shape delimited by the mould, with a constriction in the middle part of the balloon and bulges delimiting this constriction, upon which the mould along with the balloon are cooled down, maintaining inside the balloon a pressure ensuring adhesion of the balloon to the mould, and upon reaching room temperature, the pressure inside the balloon is lowered to the atmospheric pressure and a formable balloon with a fixed shape is taken out.

Preferably, the temperature used falls within a range of between 70 and 150°C.

The object of the invention is also a balloon endovascular system for the implantation of a heart valve, characterised by comprising the formable balloon defined above.

Preferably, the system comprises a tie in the form of a rope, controlling the controllable part of the outer tube.

Preferably, the system comprises an assembly of balloon tubes, which along with the balloon is independently controllable in its rotary motion relative to the lengthwise axis of the system.

The object of the invention is also a set for the implantation of a heart valve, characterised by comprising a balloon endovascular system for the implantation of a heart valve as defined above and a balloon-expandable heart valve.

Preferably, the balloon-expandable heart valve present in the set has such a length that after being clamped on the constriction of the balloon it does not exceed the length n of this constriction.

Preferably, the assembly of balloon tubes included in the balloon system along with the balloon is controllable independently in its rotary motion relative to the lengthwise axis of the system, the controllability of the angle of rotation depending on the position of radiographic markers in the support frame of the valve. An embodiment of the object of the invention is presented in a drawing, wherein fig. 1 presents a distal part of the endovascular system with an inflated balloon for the implantation of a balloon-expandable valve, fig. 2 shows the distal part of the system with a folded formed balloon in a position intended for clamping the valve thereon and introducing the system to a patient’s body, fig. 3 shows the distal part of the system with a folded formed balloon, with the valve clamped thereon, fig. 4 presents the distal part of the system with an inflated balloon and the valve expanded thereon, fig. 5 shows an endovascular system for the implantation of a heart valve comprising a folded formed balloon prepared for clamping the valve thereon, fig. 6 presents the system with an inflated balloon without a valve, fig. 7A presents the system with a folded formed balloon and a valve clamped thereon, indicating the places of cross sections A-A, B-B and C-C, fig. 7B shows a magnified cross-section of the system in the plane A-A, fig. 7C shows a magnified cross-section of the system in the plane B-B, fig. 7D shows a magnified cross-section of the system in the plane C-C, fig. 8 shows a magnified example of a final valve frame with connectors formed by lock members and with elements for mounting the commissures of the valve, with an “S” area marked; fig. 9 shows the magnified “S” area of fig. 8 as a fragment of the frame with a sample distribution of markers in the form of black dots; fig. 10 shows a magnified fragment of the valve frame with multirow locks and their corresponding lock-receiving means, in a disconnected position; fig. 11 presents a fragment of the frame and several magnified types of locks in the valve frame; fig. 12 shows a magnified fragment of the frame with indicated widths of the individual strut members or elements of the valve frame pattern; fig. 13 shows several magnified examples of elements for mounting the commissures of the valve; and fig. 14 shows a sample magnified valve in the form of valve cusps mounted on a support frame.

The formable balloon for a heart valve according to the invention is characterised by consisting of a conical proximal part 22 with the length k, a conical distal part 24 with the length m and a preferably cylindrical middle part 23 placed between them, with the length /, the balloon 21 having the indicated shapes of its individual parts in its inflated (unfolded) state, with a larger diameter. In the folded state, meaning in a state ready for a valve to be clamped thereon (and transported in the patient’s body to a target location), with a smaller diameter, the formed balloon 21 comprises a constriction 26 with the length n, preferably lower than the length l of the middle part 23, the constriction 26 being delimited at the distal and proximal sides by the proximal 27 and distal bulges 28, widened relative to the diameter of the constriction 26. The constriction 26 has a cylindrical or partially cylindrical shape, or it constitutes a portion of a cone, or it is a combination of the abovementioned shapes, and the boundary between the constriction 26 and the bulges 27, 28 can be approximately stepped and identical from the sides of both bulges 27, 28. The constriction 26 can have a diverse shape (varied diameter) over the length n and, e.g. have a smaller diameter in the place where the bulged part with the valve cusps will be located after clamping the valve. Regardless of the diverse shape of the constriction 26, the bulges 27, 28 delimiting it have a larger diameter (or thickness) than their neighbouring edges of the constriction 26. The distal and proximal edges of the constriction 26 are preferably placed at the same distance from the distal and proximal ends of the balloon 21, meaning that the constriction 26 is placed symmetrically in the middle of the balloon 21, in the area of its cylindrical middle part 23, preferably symmetrically in the middle of this part 23. The proximal bulge 27 partially comprises the proximal fragment of the cylindrical middle part 23 of the balloon, and the distal bulge 28 partially comprises the distal fragment of the cylindrical middle part 23 of the balloon. The proximal 27 and distal 28 bulges are the widest (they have the largest diameter) in the vicinity of the constriction 26, and then their diameter or width can be decreased in such a manner that the bulges 27, 28 become narrower when moving away from the constriction 26, in order to, in a sample variant, become equal to the diameter of the distal soft tip 25 from the distal side and become equal to the diameter of the inner tube of the system from the proximal side. The bulges 27, 28 are shown in a sample embodiment; however, modifications of the shape of the formable balloon aimed at producing an analogical result will be obvious to a person skilled in the art, i.e. the bulges can have the shape of an elongated cone, a pear-like shape, a cylindrical shape or the shape of an elongated water drop. The bulges may not have a symmetrical shape relative to the lengthwise axis of the system, i.e., e.g. in a section crosswise relative to the abovementioned axis, these bulges can have an oval shape. The described bulges 27, 28 have a spatially fixed shape in a form partially unfolded relative to the constriction 26, which is folded more tightly. In the area of the bulges 27, 28, the balloon material is folded more loosely than in the area of the constriction 26. Therefore, the formable balloon has a varying degree of packing of the balloon material, i.e. in the space of balloon bulges there is more unoccupied space compared to the space of the constriction.

The indicated lengths k, l, m, n refer to segments defined relative to the lengthwise axis of the balloon and the system in which the balloon is included.

The endovascular system for the implantation of a valve comprises an assembly of balloon tubes 29, on which the balloon 21 is seated, an outer tube assembly 30, a first knob 31 controlling the bending of the distal part of the outer tube 37, a handle 32, a second knob 33 controlling the displacement of the assembly of balloon tubes 29, the balloon 21, the distal soft tip 25 and the valve 2’ clamped on the balloon 21, as well as a third knob 34 constituting a barrier for the ability to rotate the assembly of balloon tubes 29, the balloon 21, the soft tip 25 and the valve 2’ clamped on the balloon 21, by means of a fourth knob - the rotation adjustment knob 35, the balloon 21 being a formable balloon as described above, comprising, in its folded state, with a smaller diameter relative to an inflated balloon, a constriction 26 included in its entirety in the middle part 23 of the balloon 21 and being delimited from the distal and proximal sides by the bulges 27, 28. The endovascular system also comprises a Y-type tip 36 with a liier-lock with at least two entrances into two channels of the system - the balloon inflation channel and the guide channel. The handle 32 of the system, the adjustment knobs 31, 33, 34, 35 and the tip with entrances to channels of the system together constitute a proximal part for an operator, and this part remains outside the patient’s body during the implantation of a valve.

The outer tube assembly 30 is made of an outer tube 37 in which a dual-channel tube 38 is placed over a specified length. The dual -channel tube 38 has a first channel with a diameter larger than the diameter of the second channel placed in the wall space of the dual-channel tube 38. Both abovementioned channels are led substantially along the axis of the system, and they are parallel to each other, at least over a part of the length of the dual-channel tube. The assembly of balloon tubes 29 is led via the first channel, while the second channel, with a smaller diameter, constitutes a tie channel 39, through which the tie 40 is led. The dual-channel tube 38 can have a thicker wall in an area where the tie channel 39 is placed.

The tie 40 has the form of a rope, meaning a bundle of wires, due to which it does not stiffen a catheter shaft, since it is easily bendable when applying force, therefore facilitating its introduction into a patient’s body. At the same time, placement of the tie 40 in the closed space of the channel of the dual-channel tube minimises the deformation of the middle part of the outer tube where the dual-channel tube 38 is placed. The tie 40 extends between a mechanism controlled by an operator by means of a knob 31, and a controllable distal end of the resulting bend of the outer tube 37. It transmits the force necessary to bend the distal part of the outer tube 37 between the mechanism controlled by the knob 31 and the distal end of the outer tube 37.

The assembly of balloon tubes 29 comprising a middle tube 41 and an inner tube 42 is led inside the first channel of the dual-channel tube 38 . The tube channel 41 is used to inflate the balloon and the tube channel 42 is a channel for the guide.

Fig. 7A shows the system according to the invention with indication of cross- sections, i.e. section A-A in the distal part of the assembly of balloon tubes 29 located in the vicinity of the balloon, section B-B in the controllable part of the system and section C-C in the stiffening part of the system. The controllable part of the system is a part of the outer tube assembly 30 over the length pi amounting to, for example, between 120 mm and 220 mm (preferably between 150 mm and 180 mm) and extends from the distal end of the outer tube 37 to the distal end of the stiffening part extending over the length j>2 of the outer tube assembly 30, and the length p ₂ amounts to between 1000 mm and 1100 mm. Two segments: the controllable one with the length pi and the stiffening one with the length p2 are in each other’s direct vicinity, and in the place where these parts meet there is a change in the design of the outer tube assembly 30; namely, the outer tube 37, being a concentric tube over its part with the length p ₂ , becomes a nonaxial tube in part p with a lengthwise constriction of its side wall. The thinner side wall of the outer tube 37 is subjected to the action of a force applied to the tie 40, and the controllable part bends in a controlled manner. Moreover, the dual channel tube 38 ends along with the distal end of the stiffening part, and therefore the tie 40 is no longer led through the tie channel 39 and it is placed in a space between the outer tube 37 and the middle tube 41, which ensures easier movement of the tie when bending the controllable part. Fig. 7C shows a cross-section of the controllable part comprising the outer tube 37 and the tie 40 inside it, as well as the assembly of balloon tubes 29 next to it. Fig. 7D shows a cross-section of the stiffening part, in which the following are placed in sequence starting from the outside: the outer tube 37, the dualchannel tube 38 with the assembly of balloon tubes 29 and with the tie channel 39 placed in the side wall. The controllable part can be made of a material different from the stiffening part, materials enabling additional stiffening and strengthening of the stiffening part and providing higher flexibility of the controllable part being known to persons skilled in the art.

The assembly of balloon tubes 29, on which the balloon 21 along with the clamped valve 2’ is seated, is connected by its proximal part to the fourth rotation adjustment knob 35. The rotation adjustment knob 35 enables an operator to adjust the rotation of the valve clamped on the balloon relative to its axis, so that, during its expansion, the risk of obstructing coronary vessels by elements of the valve would be limited to a minimum. In addition, the knob 34 enables the adjustment of force necessary to rotate the assembly of balloon tubes 29. At the proximal side of the balloon 21 there is an assembly of balloon tubes 29, whose cross-section A-A is shown in an embodiment in fig. 7B.

The system can comprise markers visible via imaging techniques, indicating the position of specific crucial elements of the system, e.g. the beginning and the end of the balloon, the beginning and the end of the middle part of the balloon, edges of the bulges of the formable balloon, etc. Along with the rotation adjustment system, these markers allow minimising the risk of obstructing coronary vessels during the implantation of the valve.

The process of manufacturing a formable balloon according to the invention involves subjecting a balloon folded in a known manner to processing under the impact of temperature and pressure and shaping it in a defined manner: The balloon is first folded by conventional, typical methods by arranging the balloon into wings and folding them by placing one over the other, in order to achieve an ordered structure with a minimum diameter. The balloon is subsequently placed in the closed space of a mould with a shape corresponding to the planned shape, i.e. in the inner space, where the balloon is placed, this mould has a constriction in the middle part and bulges delimiting this constriction. In the next stage, the mould is heated up along with the balloon to a temperature ensuring plasticity of the balloon, i.e. the susceptibility of plastic of which the balloon has been made to being shaped. The temperature can fall within a range of 70-150°C. Subsequently, via the pressure differential between the pressure inside the balloon and the pressure inside the mould, i.e. negative pressure in the mould or positive pressure in the balloon (for example, achieved by inflating the balloon with a neutral gas), in the closed space of the mould the balloon is given its shape with the constriction in the middle part and bulges on both sides of the constriction. The mould is subsequently cooled down along with the balloon, with the pressure differential maintained. The balloon material is given a fixed shape. The term “fixed” means that the shape of the balloon is maintained during its mounting in the endovascular system and when clamping a valve thereon, and it will change during its inflation during the implantation procedure, it being apparent to a person skilled in the art that the formable balloon material remains flexible and its imposed shape will, e.g. succumb to squeezing, but it returns to its imposed shape. The pressures are equalised after cooling the balloon and the mould to ambient temperature. The balloon is removed from the mould by unfolding the mould. The balloon retains its imposed shape until its inflation during the valve implantation procedure.

The final balloon is seated in a known manner on the distal end of the assembly of balloon tubes.

A medical product in the form of an endovascular system comprising a formable balloon has a design known to persons skilled in the art, and modification of the system according to the invention involves using a specific formable balloon described above. The system according to the invention also uses a tie for bending the controllable part and a mechanism enabling rotation of the balloon relative to the lengthwise axis of the system, in a controlled manner. The endovascular system is dedicated to the implantation of a replacement valve, the valve material having to be stored up until the moment of implantation under specific, sterile conditions, in a specially prepared protective fluid. The medical product constitutes a set of an endovascular system comprising a formable balloon along with a valve as a separate element, which comprises a support frame, as well as valve cusps and a sealing flange seated thereon (stitched). The seating of the valve (the support frame along with the stitched cusps and sealing flange) on the formable balloon takes place prior to the implantation of the valve. The valve in its unfolded or partially unfolded form is slid over the constriction of the formable balloon and it is clamped on the balloon to reach the minimum diameter of the valve.

The valve frame, as well as the valve, are adjusted in their size to the size of the constriction in the formable balloon, and, more precisely, the length of the valve measured along the valve axis upon clamping on the formable balloon fits in its entirety in this constriction, meaning that the length n of the constriction of the balloon is larger or equal to the length of the valve upon being clamped on the balloon. Preferably, the distal and proximal edges of the valve clamped on the balloon abut the edges of bulges delimiting the constriction of the formable balloon. At the same time, it is preferable for the valve clamped on the balloon to result in a diameter of the endovascul ar system which in this place is close to the diameter of bulges of the balloon neighbouring the valve clamped on the constriction, e.g. the valve clamped on the balloon should have a diameter ranging from 0.6 to 1.4 of the diameter of the bulges of the balloon, preferably from 0.9 to 1.1 of this diameter.

The diameter of the bulges of the balloon can be larger by from 0.3 mm to 0.5 mm or up to 1.0 mm or up to 3 mm, or even up to 4 mm compared to the diameter of the constriction, so that the profile of the valve upon its clamping over this area of the constriction would not protrude beyond the delimiting bulges (as shown for example in fig. 3).

The balloon formed during inflation is at first inflated in the space of the bulges, which are partially “open” in a state prior to the implantation of the valve. Higher resistances must be overcome over the length of the constriction; therefore, the balloon is inflated slightly more slowly. This causes the valve to be continuously delimited by inflatable bulges during inflation of the balloon and during expansion of the support frame, which enables controlling the position of the valve and prevents its displacement, deformation in the final phase of implantation. Due to the constriction applied thereto, the formable balloon also has a highly precisely indicated place in which the valve is positioned prior to its clamping on the balloon.

A preferable valve support frame used in a set according to the invention is a support frame presented in patent application P. P.430463, as presented in. fig. 8. Figures 9, 10, 11, 12, 13 present a detailed structure of the frame, using a segment of this frame as an example, which has been indicated by wavy lines on the sides of images.

The valve frame has been made out of a special material in the form of specially prepared sheets of metal or metal alloys, which sheets, by subjecting the material to special processing, exhibit anisotropy of the crystalline structure of the base material, obtained by proper orientation of the crystalline structure during the preparation of a blank. Said effect of an arranged, linear crystalline structure of metal (a metal alloy) occurring in the entire sheet of which the frame is made follows the direction of fibres generated when subjecting it to plastic processing. Such anisotropic arrangement of the structure in a sheet of metal or a metal alloy in which fibres are arranged linearly can be achieved by any known methods of plastic processing, such as, e.g. cold rolling, with or without additional heat processing. The sheets used are rectangular or square, with dimensions which are fixed for the dimensions of the target valve frame, or it is also possible to use sheets with a surplus on sheet margins, so that their specified dimensions (length and width) are not applied until cutting out the frame or cutting out the locks or cutting out the stmt-based structure.

In the frame, it is possible to use a sheet in which the longer side of the blank follows the direction of fibres created during plastic processing; a sheet in which the longer side of the blank is transverse to the direction of fibres created during plastic processing; or a sheet in which the longer side of the blank is at an angle of 5° - 85° relative to the direction of fibres created during plastic processing. Preferably, the first or third sheet type is used, which means the use of sheets in which the side of the sheet which forms an annular periphery of the frame follows the direction of fibres created during plastic processing, or it is at an angle of 5° - 85° relative to the direction of fibres created during plastic processing. In other words, in preferable sheets, the side of the sheet which forms an annular periphery of the frame is at an angle of 0° - 85° relative to the direction of fibres created during plastic processing; preferably, it falls within a range between 0° and 60° or between 0° and 45°; or it is preferably close to 0° or falls within a range between 0° and 30°, preferably 0° and 20° or 0° and 10°; or it is close to 45° and falls within a range between 35° and 55°. Such orientation of the crystalline structure in the sheet allows using the anisotropy of the structure of the material in order to modify the mechanical properties of the valve frame, and in particular increase its radial force. It is particularly preferable to use the first sheet type, in which, after cutting out the profile (pattern) of the valve frame, the linear arrangement of the crystalline structure in accordance with the direction of fibres created during its processing extends in a direction transverse (at an angle of 90°) in relation to the axis of symmetry of the valve frame, because of the radial force of the final product. It is also preferable to use the third sheet type, in which the linear arrangement of the crystalline structure of the metal (metal alloy) is skewed in relation to the axis of the final valve frame, i.e. at an angle between 5° and 85° relative to this axis, because of the physical features of the resulting frame, i.e. an increased radial force. It is also possible to use a sheet in the form of a laminate resulting from superimposing and combining two, three or four sheets, each sheet of which has an anisotropic crystalline structure, different from the others, e.g. by using two sheets with a crosswise arrangement of the flow direction of the material. A multi-layered sheet (preferably two-layered) constructed in such a manner will allow taking advantage of the anisotropy of mechanical properties of the individual layers of material in order to improve the mechanical properties of the final product: the valve frame. Regarding such laminate, for the needs of the invention, each of its layers is arranged linearly relative to its crystalline structure, and preferably, in these combined layers, it is either directed perpendicular to the frame axis or at an angle falling within a range between 5° and 85° relative to this axis. Preferably, the multi-layered sheet is a two-layered sheet and the layers are arranged crosswise, meaning that each one of the layers has an arranged, linear skewed crystalline structure relative to the frame axis, but the linear structure of one layer relative to the other layer differs by 90° or 45°, or the crossing of structures falls within a range between 10 and 80°.

It is also possible to use more than one sheet of material, e.g. two or three or four sheets of material, in such a manner that the consecutive sheets constitute the consecutive parts of the frame annulus periphery, and a connector based on the combined locks and lock-receiving means is formed between them. Thus, when the frame is made of two sheets, then two lines of locks - lock-receiving means connectors are formed on the periphery of the frame, and in the case of three sheets of material, three lines of locks - lock-receiving means connectors are formed on the periphery of the frame.

The edges with locks are connected to the opposite edges, meaning those with the lock-receiving means, retaining a single plane of the product, i.e. elements with opposite edges are connected in a position moved face to face, with no mutual overlapping of the elements of sheets in any area. In this manner, a single layer of the material - the sheet - is retained in the sheet connection area. It is possible to make a minimal addition of a binder material resulting from the used process of glueing or welding the locks; however, in terms of thickness, the generated connector is either substantially the same as the remaining part of the frame, or it is Only slightly different from the thickness of other areas of the frame structure. Preferably, the cutting of locks in the consecutive rows of frame struts proceeds at an angle relative to the axis of symmetry of the final frame. The frame has a multirow construction, i.e. it consists of rows of strut members surrounding rows of cells (eyelets), and each row of struts has its assigned lock and its corresponding lock receiving means. Therefore, the locks also have a multirow form and they have the form of protruding studs, shaped in a manner adjusted to the shape of the means receiving these studs. The locks engage the lock-receiving means, i.e. the locks and the lock receiving means are mutually adjusted in shape in order to cause an effect of hooking, catching the individual rows of frame struts. A connector formed from the locks and the lock-receiving means bonds each row of struts. In order to maintain the minimal profile of the frame and attain the best possible physical properties of the frame, said connectors are consecutively offset relative to each other on the periphery of the frame, so that the connector from the first row of struts (on the first frame edge) is the most distant from the connector from the last row of struts (on the second frame edge). Such mutual offset of the consecutive neighbouring connectors can extend such that the neighbouring connectors form a skewed line relative to the frame axis, or they extend along a curve or along a spiral line on the outer surface of the frame.

For example, sheets made of cobalt and chromium alloys, produced in a cold rolling process, with thickness of 0.4 - 0.5 mm, were used to manufacture the frame, the cutting steps having been performed using a laser method, and the joining of the locks and the lock-receiving means having been performed using the welding or soldering technique.

The valve frame is made of, i.e. it comprises in its structure a sheet or sheets connected in a cylindrical shape, out of which the frame pattern is cut out, so that it has a latticed (meshed) construction consisting of two areas: an area with smaller cells 5 located at one end of the frame 2 and an area with larger cells 6 located at the opposite end of the frame 2, the structure of the frame consisting of several rows of struts, which in the inner area with smaller cells 5 of the frame 2 form nodes X, so that four arms (couplings) Y extend from each of them and the cells of this area have the shape of a regular polygon. The rows of smaller cells 5 in the neighbouring rows are offset relative to each other by half of a cell, relative to the frame axis, so that the nodes X, in every second row of these nodes, are situated in a single line along the frame (one above the other). In a row on the frame edge, the area with smaller cells ends with the tops V, which in pairs form the arms Y extending from the nodes X in a row neighbouring the edge row of the cells 5. The area with larger cells 6 neighbours the area with smaller cells and it is formed such that mutually parallel brackets Z extend from the tops U of the arms Y in a row surrounding the smaller cells in the last row (ending the area of small cells), passing on the frame edge through the couplings W into arms ending the frame with tops analogical to the tops V on the opposite end of the frame 2. The larger cells 6 of the frame 2 have the shape of a regular polygon, whose two lower edges and two upper edges are formed of arms Y neighbouring each other in pairs, and two longer opposite sides parallel to the frame axis are formed of brackets Z. The brackets Z in the frame are arranged substantially parallel to each other. The length of the larger cells 6 is at least 10% larger than the length of the smaller cells 5, said dimensions being assessed in the expanded position of the frame, relative to the axis of symmetry of the frame.

The individual elements of the strut structure of the frame can have a varying width, as shown in more detail in fig. 12, where the widths of the arms Y and the brackets Z have been indicated in the individual rows of struts of the valve frame. The width d of the arms Y equals the width c of the arms Y in the neighbouring row of arms (in the opposite arms surrounding the smaller cell of the meshed structure); the width of the arms b in the outermost row surrounding the larger cells from the side of the smaller cells can be larger by approx. 5% to 30% than the width c, or it equals 1 to 1.2 times the width c; likewise, the width f of the bracket Z, located in the area of larger cells, can be larger by 5% to 30% of the width c, or it equals 1 to 1.2 times the width of the strut c, and the width a and e of the arms Y from the outermost rows, located on the opposite edges ending the frame, is larger by 10% to 150% of the width c, or it equals 1.2 to 2 times the width c. Such distribution of the width of individual elements of the frame pattern has provided the attainment of proper frame geometry during expansion of the frame with a valve on a balloon; it has provided the attainment of proper radial force and rigidity in the upper part of the frame necessary to maintain the commissures of the mounted valve.

The frame based on the above design can also have another form, i.e. another number of rows, struts, another size thereof; it can also have another meshed shape, e.g. the arms of the individual struts can be undulated, sinusoidal, elongated, connected by additional couplings in a lengthwise and/or transverse direction in relation to the frame axis. The designs of valve frames known from prior art dedicated to implantation in the procedure of expansion on a balloon, as well as, in an auxiliary manner, the designs of stents, can be applied to manufacturing of the frame. It is obvious to a person skilled in the art that the cut-out design of the frame in an assembled state, clamped on a balloon, should provide a minimal size of the prosthesis, i.e. the cut-out elements of frame patterns in a folded position abut each other, so that the contracted structure would form a cylindrical shape with a minimal diameter, and during expansion it would easily unfold and expand in a transverse direction caused by the inflations of the balloon. The frame is cut out of a sheet or sheets of material which, after combining, forms (form) the shape of an annulus; however, during expansion of the frame on a balloon, it is possible to attain a modified shape of the frame, which can be cuplike at one side or have an extended form at both ends, etc.

Apart from the strut-based design described above, the frame 2 is provided with locks 3 and, at the side abutting these locks, with receiving means 4 for these locks. Fig. 10 presents an example of a frame outline fragment with the locks 3 in a disconnected position, which after connecting form a fixed connector 7. The locks 3 are shaped in the form of studs protruding beyond the outline of the frame, provided with concave and convex elements from the side, which is to be hooked to analogical elements of means 4 receiving the locks 3. After engaging the locks 3 and the means 4, they interlock each other, providing application of a force maintaining a closed, cylindrical form of the frame. The number of the used assemblies of locks 3 and lock-receiving means 4 corresponds to the number of rows of struts forming the outline of the frame.

Fig. 11 presents several examples of locks 3 A, 3B, 3C, 3D, 3E which are used in a multirow arrangement in the frame. The simplest form of the used lock can be the form of a single hook 3D or 3E, seated on the lock stud, to which corresponds the reversed reflection of this hook in the form of the lock-receiving means. Such a design of the connectors is supposed to provide mutual hooking of these elements. The locks can also have the form of a more complex polygonal chain 3A, teeth, e.g. triple teeth 3C, or a double hook, as well as the form of convex rounded forms 3B. Further modifications of the shapes of the locks to which the reflected receiving means correspond (the “jigsaw” principle) will be obvious to a person skilled in the art. An arrangement of such connectors operates based on the principle of concave and convex elements maintaining each other in position when the frame already has its final cylindrical form. The used locks enable obtaining proper frame geometry and the positioning of the opposite ends of the outline relative to each other when being permanently combined. The geometry of a lock preferably affects the strength of the connector by mechanically blocking the possibility of movement of the opposite ends of the valve frame outline relative to each other.

The valve frame also comprises mounting elements 8 intended to mount the commissures - the areas where the cusps forming the valve meet, the elements 8 being placed in the frame in such a manner that they replace certain brackets Z, together with the four arms Y forming the larger cells of the frame. As a consequence, what matters is that the whole construction should be stable and symmetrical due to the symmetry of the acting forces. Preferably, in the case of the presence of 9, 12, 15 or 18 brackets Z in the frame, three of which are replaced by elements mounting the commissures, the remaining 6, 9, 12 or 15 brackets Z are distributed symmetrically among the three elements mounting the commissures.

The use of a branched element for mounting the commissures is preferable in that it is easy to put sutures in the step of mounting the valve/the valve material. Due to the presence of first protrusions 18 for attaching suture threads and second protrusions 19 arranged symmetrically at the opposite side of the element 8 for attaching suture threads, it is easier to mount - stitch the valve. The element for mounting commissures comprises at least two protrusions 18, 19 arranged opposite each other. For mounting the valve, it is also possible to use openings 20, with which the element 8 for mounting the commissures is provided. The tilt of the protrusions 18, 19 at an angle, towards one or the other frame edge, wherein preferably at least some of the protrusions are directed towards the edges enclosing the larger cells of the frame, generates forces extending and contracting the commissure, which has a preferable impact on its tightness and durability of mounting. The tilt of the protrusions 18, 19 relative to the axis of the mounting element 8 (shown in fig. 9, where the axis extends vertically along the element 8 through the openings 20) can fall within a range between 5° and 80°, preferably between 5° and 60°. Since no part of the valve cusp is folded outside the frame, and only threads/sutures are placed on the outer side of the frame, the solution preferably reduces the diameter of the frame clamped on the balloon with the valve cusps mounted and protects the material of the cusps in the place of the formation of commissures against possible damage when introducing the frame into the area of implantation. As shown in fig. 13, in the simplest variant (version 8A), the element 8 comprises straight skewed protrusions 18, 19 and openings 20 which are also used to mount threads/sutures, or constitute an area for markers. In version 8B, the element for mounting the commissures additionally comprises lower protrusions directed opposite to the remaining protrusions, towards the second frame edge, to additionally protect the sutures against slipping. In versions 8C and 8D, the protrusions 18, 19 are provided with widened ends or with bulges on their ends, providing protection against the slipping of threads/sutures. Version 8E presents another variant of the element for mounting commissures, lacking the central openings.

Fig. 9 presents possible areas for placing radiographic markers in the valve frame. From a clinical point of view, such markers can define key locations for the elements of the frame and the valve, e.g. a marker 9 of the element 8 indicates location for the mounting of the commissures, markers 10, 17 of the tops V indicate two outermost ends of the valve frame. The markers 11 of the brackets Z indicate space for placing the valve and distinguish the position of the brackets Z from elements for mounting the commissures (where two markers are placed). The markers 12 of the nodes X along with the markers 13, 14, 15, 16 of the arms Y allow assessing the position of the whole area with the smaller frame cells. The markers can take on a circular, oval or polygonal shape. Depending on the place of their positioning on the frame, they can differ in size. The markers can be placed on each row of struts or every 2, 3, 4 or 6 struts.

The valve cusps do not constitute the object of the invention; they are elements known to those skilled in the art and can be made of polymeric materials, or they can originate from animal tissues. An example of the valve in the form of valve cusps mounted on the support frame described above (of fig. 8) is shown in fig. 14.

For a person skilled in the art, it will be apparent that a balloon formed according to the invention and an endovascular system comprising such a balloon can be used with various types of balloon-expandable valves, i.e. they can include valves comprising a frame woven using wires or with a pattern cut out of metal sheets or metal alloys or tubes made of metal alloys intended for medical purposes.