This application claims the benefit of German Application No. DE 10 2008 022 673.4, filed May 7, 2008, which is incorporated herein by reference as if fully set forth.
The invention relates to an occlusion element for unwanted openings in the heart for atrial-septal defects (ASD), wherein this element is formed or braided from threads made from biocompatible metal and/or plastic, from absorbable plastic, from memory material threads, from memory-plastic threads, from Nitinol wires, or from wires or threads sheathed with plastic. This occlusion element has two occlusion disks formed from the threads. Between these disks the occlusion element has a region with smaller radial dimensions that passes through the opening in the heart. In the position of use, the occlusion disks grip over the edges of the unwanted opening in the heart on both sides.
Such an occlusion element is known from DE 10 2006 040 415 B3 and has proven effective and has the advantage compared with an occlusion element according to DE 695 34 505 T2 that only one holder, which is formed as a sleeve and projects opposite the occlusion element on one side, is required for the threads and as a connection for a feed element with which the occlusion element can be brought and placed at its defined position.
From US 2003/0055455 A1, a comparable occlusion element is known in which two occlusion disks that can be connected and one insertion instrument for each of these occlusion disks are provided and the occlusion disks can be connected to each other in the interior of the heart with the help of coupling means, such as hooks and loops or magnets.
From US 2007/0179527 A1, a comparable occlusion element is known in which the occlusion disks have an umbrella-like construction and there is a mutual connection that allows one disk to shift one inside the other with a telescoping motion. Due to its stiffness, this connection makes the insertion and the handling more difficult.
Therefore, the invention is based on the objective of providing an occlusion element of the type noted above in which a projecting sleeve or holder can be avoided and nevertheless the simplest possible insertion into a heart can be performed.
To meet this objective, the occlusion element according to the invention provides that the two occlusion disks each have a holder that fixes the radially extending threads forming the disks on one side and that project from the occlusion disks, and the holders are connected to each other for forming a spacing between the two occlusion disks that forms the region with the reduced radial dimension in the position of use. The holder of one occlusion disk has an axial opening or recess that extends outward and in which a projection of the holder of the second occlusion disk can be inserted and connected in this position. In this manner, the projection of one holder fits with a positive fit, can be screwed, and/or can be welded into the opening or recess or depression of the other holder, and at least one of the holders has a coupling point or opening facing away from the connection point to the other holder for the detachable engagement of an insertion instrument, and the coupling point or opening has a thread to which a counter thread of the insertion instrument fits.
The occlusion element can be formed according to the invention from two initially individual disks that are connected to the holders which hold the braiding or the threads of these disks together, so that the holders come to lie between the two disks. That is, no disks require a holder that projects outward and that could negatively affect the blood flow in the heart atria. In this way, not only is a tension-resistant connection produced, but in the case of welding, a connection is produced that is no longer even detachable for the two disks and thus features correspondingly greater stability.
Furthermore, a detachable connection of the insertion instrument with the occlusion element is possible in a simple way. For example, the opening on the holder could have internal threading and the insertion instrument could have matching external threading at its distal end.
Here it is useful if the holder of at least one occlusion disk has a coupling point or opening that faces away from the connection point to the holder of the other occlusion disk and that is used for connecting to the feed instrument, wherein the threads or the mesh width of the braiding of the occlusion disk are open or leave a passage for the feed instrument.
The braiding of such an occlusion disk usually has a wide mesh and is pliant so that a feed instrument can be pushed through in a simple manner, in order to reach one of the holders located between the occlusion disks and here the holder that has the coupling point for connecting to this feed instrument. Thus, the occlusion element can be gripped in a known manner with a feed element and brought to its defined position, without a holder or sleeve having to project outward on one side of the occlusion element and possibly negatively affecting the blood flow in one of the atria. It is especially favorable if the holders of the two occlusion disks facing each other in the position of use are connected to each other in a load-resistant manner. Thus, on one hand they can easily withstand the forces during the implantation procedure and, on the other hand, the forces possibly occurring during use, without being able to be moved apart from each other.
An advantageous construction provides that the two disks are connected to each other elastically in the position of use, that is, the spacing can be changed somewhat against a spring force, in order to allow a tight contact of the two disks on both sides of a heart wall and in this way to be able to take into account heart walls of different thicknesses.
The axial opening or recess of the holder of one occlusion disk can have internal threading and the matching projection of the holder of the second occlusion disk can have a matching threaded piece or external threading for screwing the two holders together. Thus, through such screwing, the tension-resistant connection can be established and secured by additional welding.
The coupling point or opening for the insertion instrument could be provided on the holder that carries the projection for coupling with the holder of the other occlusion disk. Thus, this holder has sufficient material and substance, in order to be able to form an opening, while the other holder, on its side, already has a recess or depression, so that another recess for the insertion instrument would be possible only through a corresponding extension.
The outer contours of at least one of the occlusion disks could be circular or could have a shape deviating from a circle. The occlusion elements could also have peripheral contours adapted to different anatomical relationships.
A simple embodiment is produced when the two occlusion disks are the same size or especially when the occlusion disk to be arranged in the right atrium is smaller than the other occlusion disk. Above all, the mentioned alternative allows the different blood pressures in the two atria to be taken into account and the larger occlusion disk to be arranged in the left atria in which it must withstand a higher blood pressure.
A modified embodiment can provide that the occlusion disk for the right atrium has a small number of threads or wires compared with the occlusion disk for the left atrium. This is possible because the blood pressure in the right atrium is less than in the left atrium. Thus, the number of wires or threads for the right atrium can be reduced, that is, less metal is to be housed in the heart accordingly. Simultaneously, the insertion instrument, as a rule, a catheter, could have a narrower configuration.
Above all, for the combination of individual or several of the previously described features and measures, an occlusion element is produced for unwanted openings in the heart with two occlusion disks that are spaced apart from each other and that are each formed from threads or a braid. Between these disks there is a region of smaller cross section that is formed at least essentially from the two holders or sleeves, with which the threads or braids of the occlusion disks are held, so that no sleeves or holders are needed on the outer faces of the occlusion element facing away from each other. Furthermore, each occlusion disk can be produced individually, which leads to a simpler production or braiding process than if two occlusion disks are formed by a common braiding process.
Below, an embodiment of the invention is described in greater detail with reference to the drawing. Shown in partially schematized representation are:
An occlusion element shown primarily in
This occlusion element 1 is formed from memory material threads 2, for example, from Nitinol threads or from wires or threads sheathed with plastic or also from memory plastic threads and advantageously braided, but could also be made from threads 2 made from biocompatible metal and/or plastic, e.g., from absorbable plastic. Above all, taking into account
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The projection 10 of the holder 6 here fits with a positive fit into the opening, recess or depression 9 of the other holder 5 and can thus be screwed and/or welded when the mutual connection is completed.
However, it is also conceivable that the axial opening or recess or depression 9 of the holder 5 of one occlusion disk 3 has internal threading and the matching projection 10 of the holder 6 of the other occlusion disk 3 has a matching threaded piece or external threading to allow screwing the two holders 5 and 6 together, which could be sufficient for mutual attachment, but could optionally also be secured by welding.
The holder 6 has the already mentioned coupling point or opening 7 on the side facing away from the connection point with the other holder 3 and provides, in the embodiment, a thread that is complementary to a counter thread on the distal end of the insertion instrument 8, wherein preferably the coupling point or opening 7 has internal threading and the insertion instrument 8 has matching external threading. Thus, the insertion instrument 8 can be coupled in a tension-resistant and compression-resistant way with the occlusion element 1 in the way shown in
The coupling point or opening 7 for the insertion instrument 8 is here provided on the holder that carries the projection 10 for coupling with the holder 5 and its opening or recess 9 of the other occlusion disk 3, because an additional coupling point or opening 7 on the holder 5 would not be possible without extending the holder 5 due to the mentioned opening or recess 9.
The outer contours of the occlusion disks 3 are circular in the embodiment according to
It should also be mentioned that instead of the direct connection of the two holders 5 and 6 like those provided in the embodiment, a connection that also has an intermediate piece would also be conceivable if the dimensions, on one hand, of the holders 5 and 6, and, on the other hand, of an opening to be closed in the heart makes this appear to be useful or necessary.
The occlusion element 1 is used for closing an unwanted opening in the heart and has, for this purpose, two occlusion disks 3 formed from a braid or threads 2, wherein the threads 2 and the braids of these occlusion disks are held by a sleeve or holder 5 and 6. The two occlusion disks 3 are here initially separated and can be connected with their two holders 5 and 6 pointing toward each other for forming the final shape of the occlusion element 1, so that the holders 5 and 6 form a spacing between the two occlusion disks 3 and a region 4 with radial dimensions that are reduced compared with the occlusion disks 3 arranged in parallel, so that there are no projecting holders for the braids or threads on the outsides or end faces of the occlusion element 1 and its occlusion disks 3 facing away from each other.
Number | Date | Country | Kind |
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102008022673.4-35 | May 2008 | DE | national |