In-wall supporting frame of heart valve bioprosthesis and heart valve bioprosthesis

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an intramural or intraparietal, rigidity reinforcing frame intended for integration in the heart valve bioprosthesis, which is based on biological heart valve in which the valve plane defined by the flaps, laterally attached, along with the commissures to the outer tubular wall. The frame is designed to be placed in the organic tissue of the cardiac valve; it consists of a bearing and secured to the stabilizing part intended for insertion within the outer tubular wall of the heart valve in order to increase the rigidity of its design, which ensures the preservation of shape of the heart valve after implantation. The invention also relates to a bioprosthetic valve, so the strong frame.

BACKGROUND

In the field of cardiac surgery associated with replacement heart valves, are currently used mainly artificial valve prostheses typically are metal valves whose surface is covered with a synthetic cloth or bioprosthetic normally forming valves of animal origin, prepared for implantation in the human body. Bioprosthesis can be divided into two groups: the prosthesis with the stent and prosthesis without a stent.

For prostheses, bioprostheses belonging to the category, the present invention provides a new approach to enhance the biological part of the prosthesis is usually an animal heart valve; This approach consists in the introduction of the reinforcing rigidity (reference) of the frame into the tissue of the heart valve and differs both from the manner in which the valve of animal origin is used without increasing its stiffness (in the case of prostheses without stent) and the method of stiffening the valve by fixing the stent on the surface of the valve (in the case of prostheses with a stent). Frame that allows to manufacture and apply this new type bioprosthesis has outlined short support on which are fixed rods introduced into the fabric outer tubular wall of the biological valve parallel to the lines of intersection of this wall with the plane of the valve commissures. The proposed support frame allows to produce reinforced bioprosthetic valve, combines the advantages of having no stent valve bioprosthesis and traditional bioprosthesis stent. Indeed, on the one hand, this framework allows to receive bioprosthetic Larger (and therefore the maximum amount that characterizes the performance of the basic function of the heart valve), which is typical prosthesis without a stent (because they lack significant amounts of device, like a traditional stent ). On the other hand, this frame allows, without using traditional stent enhance rigidity of the prosthesis and thus ensure that he retains the desired shape, it can be used for this new type of reinforced bioprostheses relatively simple and rapid implantation technique used in the case of conventional bioprostheses with the stent; this is achieved by increased rigidity of the heart valve bioprosthesis and the fact that in this case needs only one seam in the plane of the valve rather than two seam for prostheses without a stent.

In this context, however, it proved that the introduction of said support frame in the outer wall of the biological valve in some cases problems may arise. It turned out that the area around the point of intersection of the line along which the plane of commissure heart valve intersects with the outer tubular wall and the plane of the valve prosthesis is particularly the structure of its constituent fibers exhibit reduced strength (referred to in the document is a point to be called "singular point commissure" or " the point of intersection "). The introduction of the rod in this area can lead to dissection of the fibers and the weakening of the organic tissue that could adversely affect the stability and workmanship of the prosthesis in such a way; in particular, the damage may further initiate a tear or detachment commissure of the heart valve.

Furthermore, since the rod of the supporting frame is fixed at a relatively short support, the implantation of the prosthesis fitted with such a frame is relatively more difficult, and therefore requires the surgeon performing the implantation, great experience.

Disclosure of invention

The object of the present invention is to solve the above problems and provide such a supporting framework for the valve bioprosthesis, which does not damage the organic tissue of the biological valve and allows for quick and easy implantation of the heart valve prosthesis produced in this way.

This invention describes a support frame for intramural valve bioprosthesis; anti carcass part comprises at least two intraparietal rod adapted to be inserted into the organic tissue of the biological cardiac valve; these intraparietal rods arranged on the base so that when the frame is placed in the biological valve rods are displaced in the lateral direction along the arc of a circle, from the point at which the line of intersection of the outer wall of the tube with the commissure plane intersects the plane of the valve prosthesis; The invention also describes a valve bioprosthesis, reinforced by at least one such frame.

The frame may further have a foundation, which is a closed ring or an open ring, ie a ring on the circumference of which there is an arc, not a member of the foundation frame.

The base and / or a fastening unit that is fastened to the opposite ends of rods of the support frame, can be coated with a biological material, such as pericardial tissue.

With the help of these funds can get the frame, giving the bioprosthetic heart valve sufficient stability and rigidity required to maintain the valve after implantation of the desired shape without damaging the organic tissue of the biological heart valve and allows not to use a traditional stent, which occupies a significant amount. In this framework can be implanted, - particularly when the substrate is an arc of a circle - with a relatively simple and rapid implantation technique which provides (assuming that all the metallic elements of the frame are closed biological material) that after implantation with the body of the patient touches only biological tissue bioprosthesis.

Other advantages of the invention result from its characteristics set out in the dependent claims and the following description in which the invention is described in more detail with reference to the drawings.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings schematically illustrate several methods of the invention, taken as examples.

1 and 2 schematically show the principle of the device and method of using two different in-wall support frame for the valve bioprosthesis.

3 shows a perspective view diagram of a third method of using the reference frame for intramural valve bioprosthesis.

4 schematically shows a perspective bioprosthesis valve equipped with intraparietal support frame used in accordance with the fourth method of use; in this example the prosthesis between the root of the aorta and the ascending aorta.

EMBODIMENTS

The invention will be described in detail with reference to the accompanying drawings. The object of the invention is enhanced valve bioprosthesis prepared to replace a heart valve. Such a heart valve prosthesis can be implanted in a position semilunar (aortic), in the mitral position (bicuspid), tricuspid or gap (tricuspid) valve must be oriented according to the direction of blood flow. The invention relates primarily to the reference carcass devices needed for the manufacture and implantation of the prosthetic heart valve.

Before proceeding to the description of intramural support frame and reinforced them to the heart valve prosthesis, it is useful to give a brief description of the structure of the natural human heart valve, starting from the structure of a biological valve replacement. This description will contribute to a better understanding of the functioning of the support frame and means of administration carcass valve bioprosthesis to enhance its rigidity.

Such a valve (as an example we can consider the animal aortic valve or valve bioprosthesis schematically represented in Figure 4) located in the aorta 20 between the aortic root 21 and the ascending aortic arch 22. Heart valve 10 in general has three leaflets 11a, 11b and 11c defining the plane of the valve and an outer tubular wall 12, which is a portion of the tubular wall of the animal aorta and now surrounds the valve plane; flaps affixed to the outer tubular wall 12 at the edges. The valve has, moreover, for each pair of flaps 11a, 11b and 11c, separating the sash triangular (in general appearance) vertical walls called commissures (13) extending from the outer tubular wall towards the center of the valve or to the mitral and tricuspid positions, - towards the center of the respective cavity of the heart. Commissures 13 are connected, on the one hand, the two edge portions of the valves 11a, 11b and 11c directed to the interior of the valve or to the mitral and tricuspid positions - to the middle of the respective cavity of the heart, and on the other hand, they are connected to the outer tubular wall 12. Therefore, blood can flow from the root of the aorta 21 into the ascending aortic arch 22 (or from the respective atrium to ventricle cavity) as shown by the arrows in Figure 4, whereas blood flow in the reverse direction is impossible. The biological valve, which serves as the biological components of the amplified bioprosthesis generally taken their aorta of the animal, and in case of replacement of the aortic valve, taken here as an example, the boundary of the outer tubular wall 12, to which are attached commissure 13 (this boundary is located relative to the plane of the valve in the direction blood flow) usually has a shape close to a sine wave. Such a shape allows, on one hand, include prosthesis points belonging sinotubular junction 14 to be the highest (with respect to the plane of the valve) the points of contact between the outer tubular wall 12 and the commissures 13, and on the other hand, leave sufficient space for the right coronary 23a artery or left coronary artery 23b, which runs close to the boundary of the right sinus of Valsalva 24a or 24b of the left sinus of Valsalva, respectively. Tubular side wall 12 corresponding to the non-coronary sinus 24 may also have a sinusoidal border.

Having considered the structure of the natural aortic valve, which in general is the structure of a biological heart valve 10 used for the manufacture of heart valve bioprostheses can better understand the structure of the invention reference frame intraparietal, an example of which is shown in Figures 1 and 2.

1 illustrates a first method of using the essence of the invention intraparietal support frame 1 intended to be integrated into the valve bioprosthesis comprising biological heart valve 10 having the structure described above. This intraparietal support frame 1 is adapted to accommodate - at least partly - inside the organic tissue of the heart valve 10, as long as it contains base 3 and the stabilizing part 2 attached to the base 3. The stabilizing part 2 intended for insertion into tissue the outer tubular wall 12 of the heart valve 10 to enhance the rigidity of its structure that is necessary for preservation of the heart valve 10 its shape after implantation.

To prevent damage to areas of weakness surrounding a singular point commissures 13, which was mentioned in the introduction, the stabilizing part 2 of the support frame has at least two intraparietal rod 2a, 2b, adapted to be inserted into the organic tissue of the heart valve 10; these intraparietal rods 2a, 2b are fixed on the basis of 3 so that after introduction of the frame in heart valve 10, these rods are displaced along the circular arc in the lateral direction from the intersection of a line along which the plane of the commissures 13 of the heart valve 10 collides with the outer tubular wall 12, and the plane of the valve 10 of the valve prosthesis.

Due to lateral displacement intraparietal rods 2a, 2b apart from the intersection point avoids damage to the fiber structure in the area surrounding this point of weakness, thereby increasing the stability and quality of the amplified valve bioprosthesis. If intended for an adult heart valve 10 has an outer tubular wall 12, the circumference of which is approximately 3-4 cm, then the magnitude of lateral displacement of the point of intersection is at least about 2 mm and may be increased up to about half the distance in height between the sinotubular compound 14 and the lowermost points of the sine wave, which is the boundary wall of the outer tube 12 located between the (circular arc) uppermost points 14 belonging to the sino-tubular junction. In fact, outside the area of ​​weakness surrounding the point of intersection, the rigidity outer tubular wall 12 rather constant, and the location of the input is this sensitive area intraparietal rods 2a, 2b is chosen so that the rods of the support structure 1 is far enough away from this area, but This would still provide the desired shape stability of the heart valve prosthesis.

When the frame 1 is placed in the heart valve 10, preferably to intraparietal rods 2a, 2b, forming the stabilizing part 2 are arranged on the basis of 3 so as to be equal to each other, their lateral displacement of the point on 3 corresponding to the point of intersection. This is shown schematically in Figures 1 and 2; at the last, a second method of use according to the present invention, the support frame 1, having more than two cores; in this example there are six intraparietal rods 2a-2f. In configurations that differ greatly from that described, the number of cores 2 and the magnitude of lateral offset relative to the point of intersection can of course be chosen different than the configurations taken as examples; in particular, the lateral displacement may be irregular. In particular, when used for more than two intraparietal rods 2, displacement rods can be selected larger than the above-mentioned half the distance in height between the sino-tubular junction 14 and the lowermost points of the sine wave, which border the outer tubular wall 12 located between points belonging to the sino-tubular junction 14.

Preferably, two intraparietal rods form a right angle with the base 3. Then, after placing the frame 1 in the heart valve 10 to obtain amplification valve prosthesis rods 2 will be displaced laterally and parallel to each of the lines of intersection of the outer tubular wall 12 with the planes of the prosthetic valve commissures 13 heart 10. Essentially perpendicular connection between the rod 2 and the base 3 where both the rod 2 are parallel to the axis of the heart valve 10, facilitates the introduction of the frame 1 in the heart valve 10.

Preferably, two intraparietal rods supporting frame 1 according to the present invention are straight. They can also take the form of a helix, forming miniature "corkscrews"; in that case they will include surface portion is a spiral line, which can contribute to stable fixation of the frame 1 in the position in which it is introduced into the tissue of the heart valve 10. Further, the ends intraparietal rod 2 is not attached to the base 3, - i.e., opposite ends attached to the base 3 - can be sharpened, and thus penetrate into the organic tissue of the heart valve without significant damage to this tissue.

The base 3 of the intraparietal support frame 1 can be made of bent rods 3a, as shown in Figures 1 and 2, or may be of a straight bar, if the displacement rods 2 relative to each other slightly.

It is also preferable that the substrate 3 was made of a closed ring 3b (see FIG. 4) or the open ring 3c (which has a free area of ​​the circle), allowing to vary the position of the frame number in the heart valve 10, as shown in Figure 3. In the case of three bases, having a circular arc shape (3a) of the ring (3b) or the open ring (3c) positioning reinforced prosthetic valve surgeon performing the implantation considerably simplified and accelerated due to the rigidity of structure, which has a heart valve prosthesis base.

Intraparietal support frame 1 according to the present invention may also include at least one remote from the base portion, which is a fastening element 4 which can be attached to the distal ends of the rods from the base 2 for more secure fixation of the outer tubular wall 12. For example, fastening link may be useful, in particular when further from the base ends of the rods 2 are sharp; In this case, the fastening element can act as a protective cover covering the pointed ends and ensures the stability of the frame 1 and the immutability of the position in which he was inducted into the organic tissue heart valve 10. A fastening element 4 can be straight or curved, having a curvature corresponding to the curvature of the outer circumference of the heart valve 10 in the region where the fastener is to be placed element. Regarding the position of the fastening link on the support frame 1 of the present invention, the fastening element 4 can be oriented parallel to the bases of the segment 3 or obliquely, following the shape of sine wave, which is the boundary wall of the outer tube 12 positioned relative to the plane of the valve in the direction of blood flow. The fastening element may be bonded with only one or, if necessary, with several intraparietal rod 2 as shown in Figure 2.

Intraparietal support frame 1 according to the present invention may be constructed of materials capable of providing sufficient dimensional stability and at the same time sufficient elasticity, such as flexible, semi-rigid and / or rigid polymers, as well as of a resilient metal, such as titanium. It should produce supporting frames of different sizes, to have a set of support frames 1, allowing enhance biological valves 10 and valve prostheses have all sizes needed in surgical practice. Furthermore, the use as a basis of the open ring 3 3c can further vary the position of the reference frame in the valve 10 of the heart.

After the description of the supporting frame 1 of the present invention has been brought to this point, it remains to describe in detail the introduction of the frame 1 in the biological heart valve bioprosthesis 10 during the formation of heart valve according to the present invention.

As stated above, Figure 4 schematically shows an exemplary valve bioprosthesis 10 for replacement of the aortic valve, reinforced intraparietal support frame 1, according to the invention; bioprosthesis 20 is positioned in the aorta between the aortic root 21 and the ascending aorta 22.

This valve bioprosthesis is formed from a biological cardiac valve 10, which according to the above general description of the plane defined by the valve flaps 11 attached to the outer tubular wall 12 and extending from it along with the commissures 13, in the lateral direction. The valve 10 has at least one intraparietal support frame 1 located as described above. The valve may be equipped with three frames 1, arranged as shown in Figures 1 and 2; the frame may include as a basis three bent bars 3a; the preferred method shown in Figure 4, the valve can also be equipped with a single support frame 1, the base 3 has a shape of a closed ring 3b (Figure 4) or the shape of an open ring 3c (3).

With regard to the biological part of the prosthesis, in most cases it is a heart valve 10 of animal origin, in particular porcine aortic valve which during processing prior to implantation, is equipped with one or more one intraparietal support frame.

Once in the biological valve 10 is placed a support frame 1, two intraparietal rods such bioprosthesis normally located within the outer tubular wall 12 of a biological valve 10 parallel to the lines of intersection of the tubular wall 12 with the planes 13 commissures of the heart valve 10.

The base 3 of the frame 1 is located inside the bioprosthesis so that surrounds the valve at the valve plane; this region is also the region of insertion into tissue heart valve 10 of the support frame 1 or 2. The fastening rods units 4 are placed on the other end of the rod 2 in such a manner as required in certain cases.

The lengths of the bars 2 of the frame 1 depends on the size frame is equipped with aortic, mitral or tricuspid valve and the position of the rod relative to the sinusoidal external borders of the tubular wall 12; These lengths are usually in the range of from 3 to 30 mm. The thickness of the frame members is typically a few tenths of a millimeter. Therefore intraparietal support frame 1 allows to provide adequate stability after implantation forms a biological cardiac valve 10, in particular the form stability of its outer tubular wall 12 and the regions near the commissures 13.

Preferably, the base 3 and / or, if desired, a fastening element 4 intraparietal support frame 1 were coated with a biological material, such as pericardial tissue. In this case, since the artificial (non-biological origin), the elements are covered bioprosthesis pericardium or any other suitable biological material, biological material alone will bioprosthesis after implantation into contact with the circulatory system and body tissues of the patient.

Alternatively the base 3 and / or the fastening element 4 intraparietal support structure may be coated with only one fabric, made of synthetic material such as teflon, dacron, gorteks.

Bioprosthetic valve reinforced intraparietal support frame, of this invention can be used for replacement of the aortic, mitral or tricuspid valve, the space occupied by the device, which serves to enhance the rigidity of the prosthesis is reduced as much as possible, as not applicable conventional stent for a substantial a place. Therefore, the space reserved for the blood flow, is less crowded, and it is one of the most important positive factors after implantation.

In particular, this allows the support frame to give sufficient stability and rigidity bioprosthetic heart valve that required to maintain its shape after prosthesis implantation, while avoiding damage to the organic tissue of the biological cardiac valve, especially in the areas around the particular points commissures.

Further, bioprosthesis valve reinforced intraparietal support frame corresponding to the present invention allows the use of relatively simple and rapid implantation technique, especially in the case where the substrate has a circular arc shape, as in this case, the rods of the support frame simultaneously serve as a means of stiffening and as "reference system" to help the surgeon in charge of the implantation, precise positioning bioprosthesis inside the hard-natural lumen.

Additionally, after implantation of the valve bioprosthesis amplified, because the metallic components of the heart valve bioprosthesis closed biological material such as pericardium, biological tissue only bioprosthesis will be in contact with the circulatory system and body tissues of the patient.