WO2017137577A1

WO2017137577A1 - Method for manufacturing a stent, and stent

Info

Publication number: WO2017137577A1
Application number: PCT/EP2017/053032
Authority: WO
Inventors: Kathrin KURTENBACH; Isabel BALZ; Uwe Reisgen; Stefan JOCKENHÖVEL; Thomas Gerhard Gries
Original assignee: Innovations- Und Informationszentrum Scheiden Und Fügen E.V.; ITA GmbH
Priority date: 2016-02-12
Filing date: 2017-02-10
Publication date: 2017-08-17
Also published as: DE102016102503A1

Abstract

The invention relates to a method for manufacturing a stent in the form of a tubular support structure consisting of at least one thread, and to a stent of said type. In said method, at least one thread is helically wound onto a core, the at least one thread being laid on top of itself crosswise at points of intersection such that a tubular, helically wound non-woven fabric is created from the at least one thread on the core. In particular a selection of points of intersection is then joined, in particular welded.

Description

Method of making a stent and stent

description

Field of the invention

The invention relates to a method for producing a stent in the form of a tubular

Support structure of at least one thread and such a stent.

Background of the invention

If there is a constriction in a lumen or vessel, a stent can be implanted at that location to keep the constriction open. Such a stent thus forms a hollow or tubular vascular support.

Thus, such stents are typically cylindrical tube-like structures that are inserted into a vessel to support and hold it open. Such stents are e.g. used in coronary vessels, but also find use e.g. in arteries, esophagus, trachea, bile duct, gastrointestinal tract or urethra. One cause of such bottleneck may be e.g. Inflammation or a tumor.

In its research, the World Health Organization (WHO) states that cardiovascular disease is the leading cause of death in age-related diseases

Diseases in the western world is. In 2004, 8.5 million people died as a result of the disease. One year later there were 152,510 deaths in Germany. In the same year, more than 230,000 stents were used. In 77% of all vessel dilations

(Angioplasty) in Germany, a stent is used, on average, is calculated with 1, 3 stents per person. The current cost of a stent typically varies from $ 300 for metal stents to $ 1200 for stents with one

Drug coating, cf. Akmaz, B.L.: "Medical-technical progress in

Germany ", dissertation, University of the Federal Armed Forces Hamburg, publishing house Dr. Hut, 2008.

Typically, a distinction is made in medicine between three stent structures.

Accordingly, a distinction is basically made between spiral stents, tube stents and braid stents. In this regard, the contribution of Butany, J .; Carmichael, K .; Leong, S.W .; Collins, M.J., "Coronary Artery Stents: Identification and Evaluation," Journal of Clinical Pathology

(2005), p. 58, p. 795-804, which is hereby incorporated by reference. Spiral stents are wound from a flat rolled material and form a simple stent shape. Due to their spiral shape, they are very flexible and easily adapt to the shape of the vessel. However, such spiral stents have the disadvantage that they have a low or limited radial force and low expansion properties. The radial force is the force with which the stent is able to impart the vessel radially outwards and can therefore also be referred to as deformation resistance or radial rigidity.

Tube stents are typically made by spark erosion or laser beam welding. The stent structure is made from a semifinished product, e.g. a metal tube

cut out. Due to the diversity of these two methods come these

Manufacturing process is often used. A disadvantage of this technique, however, is the complicated post-treatment by heat treatment and electrolytic polishing to obtain a functional surface, as well as the large material loss, which is due to the manufacturing process.

European Patent EP 0 801 934 B1 describes a welded one

sine wave-shaped stent, in which a preformed sine wave-shaped wire is used. Neighboring wave trains are welded together in certain patterns. Disadvantageously, undesirable folding can occur with radial compression of such a structure.

Braid stents are typically divided into machine-braided and hand-braided stents, with machine-braided stents typically braided from multiple wires and hand-braided stents made from a single wire. Machine braided stents, such as e.g. The commercially available WALLSTENT® from Boston Scientific, Natick, MA / USA (see www.bostonscientific.com) is manufactured as a braided continuous tube and fabricated to the desired length in a subsequent process step. Due to the very flexible structure, such a braided stent is suitable for curved

Vessel walls. A disadvantage of these machine-braided stents is that the subsequent length-tailoring produces wire ends which can be sharp-edged, since the underlying braiding tube is manufactured as an endless product by machine. Such sharp-edged wire ends can lead to injuries, tissue damage and irritation when placing the stent. Tissue damage and irritation can lead to the formation of granulation tissue (scarring). This Granulation tissue can grow through the mesh of the metal stent and again lead to stenosis (constriction of the vessel).

The European patent EP 1 755 491 B1 of Boston Scientific Limited therefore describes a method for reducing stent sutures and a reduced stent

Seam profiles and closed wire configuration. For this purpose, the capped wire ends are bent over at the ends of the stent and welded.

Nevertheless, such stents, which are initially mechanically braided as an endless tube, have the disadvantage that they have a limited or low radial force. Moreover, disadvantageously, a radial elongation of these stents can result in a significant elongation, which may be e.g. Drug eluting stents (DES) can affect the drug-based coating. The same applies vice versa in the case of dilatation. Also, when loosening a weld at the wire ends again a vulnerable open wire end arise.

European patent EP 0 975 279 B1 discloses a stent with selected welded crossed threads. In this stent, a plurality of individual wires are welded together according to a selected pattern at certain crossing points. Even with this stent, however, an undesirably large elongation can occur with radial compression. Furthermore, open wire ends may also be present at the axial ends of the stent, which may involve the risk of tissue damage. In addition, it may e.g. in pulmonary stents due to stent migration / dislocation or infection, it may be necessary to remove the implanted vascular support. In this case, such stents can disintegrate if damaged in several threads, so that the removal of the doctor can be difficult and also there is a risk of tissue damage.

Hand-braided stents are manufactured manually in a complex manufacturing process. Here, the stent structure is braided by hand from a single wire. Unfortunately, the results of manual braiding of stents are poorly reproducible. Furthermore, the productivity of this manufacturing process is in need of improvement, since manual braiding requires a great deal of working time and is therefore expensive.

Typically, these stents are therefore individually hand plaited in very low cost environments.

General description of the invention The object of the invention is therefore to provide an efficient, in particular mechanized, method for producing a stent, or a stent made of a thread structure which can be produced efficiently, inexpensively and mechanistically.

A further aspect of the object is to provide a method for producing a stent or a stent from a thread structure which is safe in use and meets high medical quality requirements, in particular good mechanical properties

Characteristics relating to the radial force and length change in radial compression or dilation.

A further aspect of the object is to provide a method for producing a stent or a stent from a thread structure which has a radial force that is well adjustable within the desired limits.

A further aspect of the object is to provide a method for producing a stent or a stent from a thread structure which, despite radial compression and / or dilatation, poses a small risk of injury to the tissue. In particular, the stent should be fault-tolerant and even in the case of a hypothetical release of a connection point, as far as possible, there should be no injury-causing open end of the wire.

The object of the invention is solved by the subject matter of the independent claims. Advantageous developments of the invention are defined in the subclaims.

A method is disclosed for producing a stent from a thread structure in the form of a tubular wound fabric with the following steps:

Providing a winding core,

helical or helical winding of at least one thread on the winding core, wherein when wound on the winding core of the at least one thread at intersections cross over one another laid over, so is not braided, so that a tubular, preferably axially limited helically wound scrim from the at least one thread the winding core arises, and

Separating or detaching the tubular helically wound web from the hub.

The stent therefore essentially consists only of one or more threads wound into a tubular support structure. So there is a stent in the form of a tubular

Thread support structure of the at least one thread in the form of a tubular Geleges generated, which is therefore not braided, but only from the or in a certain Pattern superimposed filaments or helical windings exists. The thread (s) are thus deposited on the at least almost all of the successive winding layers and thus on the lateral surface, which are arranged next to one another only on the thread (s) previously laid down, ie laid thereon and not led underneath. That is, the thread or threads are not in particular by means of braiding

alternately on top of each other and under each other. The suture support structure of the stent is therefore formed by a tubular scrim where the scrim is not a braid. Furthermore, the tubular clutch is wound directly in tubular form from the at least one thread.

Advantageously, such a winding method can be very well automated or mechanically carried out on a winding core. Furthermore, such a wind-up process can be performed quickly on a winding core, so that the method disclosed here is particularly efficient and inexpensive. Nevertheless, the method is variable with respect to the desired stent parameters, e.g. Thread material, radial force, winding distance, etc., and it can produce stents of high quality, safety, reproducibility and low tolerance. In particular, the method allows a locally variable force distribution. In comparison to conventional stents, the stent according to the invention offers the possibility of a "mechanical force distribution", which makes it possible to provide the stent with a locally higher radial force at the points where, for example, an increased pressure prevails on the vessel for tracheal and esophageal stents.

In particular, the winding core has at least at a first axial to be generated

Stent first deflecting means for the at least one thread and the at least one thread is deflected loop-shaped on at least one of the first deflection. For this the following steps are carried out:

a1) The at least one thread is in a first axial direction in either a left-handed or a right-handed helical first Hin-winding on the

Winding core wound up,

a2) Subsequently, the same thread from the step a1) at the first axial end face open stent end to be generated around one of the first

Deflectors looped and looped

a3) then the same thread from the steps a1) and a2) in the

Step a1) opposite second axial direction in a right-handed or

left handed helical first return winding with the opposite to step a1) Handed on the winding core wound back and is stored at intersections on the helical first outward turn from the same thread radially from the outside.

Thus, the same thread is helically wound on the winding core at least once and then rewound in the loop in between. The diverters may e.g. ring-like arranged around the winding core radial deflection pins for each loop to be generated.

In particular, the steps a1) to a3) are carried out several times and, as a result of the multiple loop-shaped deflection of the at least one thread on the first deflection devices, a plurality of first loop-shaped deflections arise from the at least one thread between the helical outward windings and the helical backwindings that the tubular helically wound scrim is already generated during the winding of the at least one thread by the first plurality of loop-shaped deflections between the helical outward turns and the helical return coils axially delimited with at least a first axial end face open stent end. Preferably, at least almost all the thread sections are deflected at the first axial end side open stent end such that there are substantially no open wire ends on the first axial end face open stent end - typically except for the two terminating ends of the axially wound back and forth thread. In other words, the first axial stent end open at the end is formed by the plurality of annular loop-shaped around the stent axis

Deflections formed the at least one thread. The plurality of loop-shaped deflections accordingly forms the annular axial or end edge of the tubular thread support structure, which in particular has the shape of a net-like cylindrical surface.

Advantageously, an axially limited stent with a first axial stent end is thus already generated when winding, which avoids already directly on the loop-shaped deflections sharp-edged wire ends (except for the two terminating ends of the axially wound back and forth thread) and thus reduces the risk of injury, without subsequent steps for bending sharp-edged wire ends are necessary. This is efficient while producing a stent of high quality and safety against

Tissue injury.

According to a particularly preferred embodiment of the invention, the

Winding core on the first axial stent end to be generated to the first deflecting and on the first to be generated axial stent end opposite second to generating axial stent second deflecting means, ie axially on both sides

Bypasses, for the at least one thread, on and

a1) the at least one thread is wound on the winding core in a first axial direction in either a left-handed or a right-handed helical first outward turn,

Diverters looped in a loop,

a3) Subsequently, the same thread from step a2) in the opposite axial direction to step a1) in a right-handed or left-handed helixformigen first reverse winding, but with the opposite to step a1) handedness, wound back onto the winding core and is deposited at intersection points on the helix-shaped first outward turn from the same thread radially from the outside,

a4) Subsequently, the same thread from step a3) at the second axial end-side open stent end to be generated around one of the second

Deflectors looped and looped

b1) Subsequently, the same thread from step a4) in the first axial direction in a helical second outward winding with the same handedness as in step a1) is wound back onto the winding core and becomes at intersection points on the helix-shaped first return winding filed the same thread radially from the outside.

Thus, preferably at least one helical out-turn and at least one helical-back turn are formed by the same thread by looping the same thread at an axial stent end between the helical out-turn and the subsequent helical-back turn.

In simple words, the same thread is wound in the first axial direction and rewound in the opposite second axial direction.

Preferably, the steps a1) to a4) are repeated several times, so that the at least one thread in each helix-rewinding repeatedly on the previously generated helix-wise Hin-windings of the same thread and the same thread in each helixform reverse winding repeatedly on the previously generated helical formations

Windings of the same thread is deposited radially from the outside to produce the tubular helically wound scrim. By schlingenformige deflecting the at least one The first loop-shaped deflections from the at least one thread between the helix-shaped outward windings and the helix-shaped reverse windings are formed at the first deflecting devices, and second loop-shaped deflections from the at least one thread are formed between the at least one thread at the second deflecting devices helixformigen reverse windings and the helix-shaped Hin-windings, so that the tubular helix-shaped scrim already while winding the at least one thread through the first and second loop-shaped deflections between the helix Hin-windings and helixformigen reverse windings, or between the helixformigen Rear windings and the helix-shaped Hin windings, axially limited on both sides with a first and second axial end face open stent end is generated.

In other words, the same thread is wound on the winding core at least once, wound back again and wound again, but preferably several times wound alternately and repeatedly wound back and deflected on both sides between the forward windings and the back windings. In this case, the thread of all out windings and back windings is always stored radially on the previously deposited windings from the outside, i. the thread is not intertwined in particular.

Advantageously, it is thus already possible to produce a single prefabricated stent which is axially delimited on both sides by the loop-shaped deflections already during the, preferably automated, winding, which synergistically combines efficiency, cost, quality and injury safety in a synergistic manner.

In other words, the tubular helix-like wound scrim is bounded axially at least on one side, preferably on both sides, by loop-shaped deflections between the helix-shaped outward turns and the helical backward turns or between the helical backward turns and the helix-shaped outward turns of the at least one thread ,

Preferably, at least two helical forward windings and at least one helical reverse winding directly interposed therebetween, or vice versa, are formed by the same yarn, by the same yarn at both axial stent ends between the two helical outward windings and the helically shaped rearward intervening helix -Wicklung, or vice versa, axially deflected loop-shaped on both sides.

The at least one thread is thus helix-shaped or helical wound with biaxially on the winding core, wherein when winding on the winding core of at least one Thread is placed at intersections cross over each other and is not braided, so that a tubular axially limited helically wound scrim is formed from the at least one thread on the winding core.

In particular, the same thread is repeatedly helically wound back and forth between the two stent ends with alternately opposite hand. This results in a biaxial, two-layered helix-shaped tubular double-sided round scrim.

Preferably, therefore, the same thread is used for at least one, preferably for at least some, preferably even substantially all helix-shaped forward windings and helical reverse windings.

In this case, the same thread crosses over at least some, preferably in the

Essentially at all crossing points themselves.

In other words, the same thread is wound alternately in helical forward turns of a handedness and helical backwinds in the opposite direction and with the opposite handedness, laying the same thread winding by turn on the winding core, with each helical back winding spaced parallel is deposited to the previously deposited helical back windings and across the previously deposited helical out windings and wherein each helical out winding is deposited parallel spaced from the previously deposited helical out windings and across the previously deposited helical back windings.

The stent thus produced is therefore preferably a filament stent, in particular a filament stent, consisting of a single thread, which is often wound back and forth in both axial directions and deposited radially from the outside with respect to each helix-shaped winding superimposed on the axis of the winding core becomes. But it is also possible to use several threads, which are wound back and forth.

A stent consisting of only one thread has the advantage that, even if the stent is damaged, it does not break down into several threads. Thus, the removal is easier for the doctor because the doctor only has to pull on a thread and also the risk of tissue damage is lower.

Preferably, the at least one superimposed upon winding thread is added to at least some of the intersection points, in particular with itself, in particular cohesively connected to increase the radial force of the tubular helically wound Geleges.

Particularly preferably, the at least one thread superimposed upon winding on at least some of the crossing points, in particular joined with itself, in particular materially joined, e.g. welded, soldered or glued. Alternatively, positive or frictional connections or combinations thereof, e.g.

Crimping, possible.

The bonding or welding is preferably carried out before the separation or removal of the Geleges of the winding core on the winding core. In other words, the scrim is wound on the same winding core and - possibly after a step of

Thermofixing of the wound thread structure - connected or welded at the crossing points, which makes the manufacturing process simple and efficient.

For welding the crossing points come in particular

Electron beam welding, laser beam welding, resistance welding, friction welding or micro-plasma welding into consideration. The beam welding process, laser and

Electron beam welding is used in particular because of their high spatial resolution by focusing on a few micrometers, the low heat input and high flexibility.

In the case of polymer-based stents, laser welding as well as ultrasonic welding, heating element welding, etc. come into consideration. In particular, thermoplastic materials can be welded. As an alternative joining technology, here the adhesive technology offers

Although the at least one superimposed thread is preferably connected or welded at a plurality of, but not at all intersection points in order to adjust the mechanical properties of the tubular wound loop as a whole.

Preferably, the proportion of the connected or welded

Crossing points on the total number of crossing points in the range between 2.5% and 40%, preferably between 5% and 25%. In these areas, the desired radial force can be adjusted in combination with the unbroken tubular scrim, and the elongation of the tubular scrim in radial compression can be within the desired range

Limits are kept. It is particularly advantageous that the radial force can be varied locally via the stent, for example by means of appropriately targeted spot weld patterns. It can In particular, areas are provided with a higher proportion of fixed crossing points and areas, with a small number of crossing points. In this case, an oriented installation may be necessary.

Further preferably, the at least one thread at the crossing points at a crossing angle in the range of 10 ° to 80 °, preferably stored in the range of 30 ° to 60 ° above the other. In other words, the helical out-turns and the helical-back windings intersect at an angle in these regions, so that diamond-shaped openings respectively arise between two adjacent helical outward windings and two adjacent helically-shaped backward windings, thereby forming a mesh structure is formed. The network structure of the lateral surface is therefore diamond-shaped. Since the at least one thread or the helix-shaped windings is not intertwined, either the two or more immediately adjacent helix-shaped forward windings are deposited at the most points of intersection over the two or more directly adjacent helix-shaped reverse windings or vice versa ie Most of these do not run alternately one above the other and with each other.

Preferably, the tubular helix-wrapped scrim is heat-set on the winding core before the at least one superimposed upon winding filament at at least some of the crossing points is welded and / or before the tubular helically wound scrim is separated or removed from the winding core. By thermofixing before joining or before welding the round-Geleges on the winding core, the clutch better retains its tubular shape. It receives a kind of "memory" for the scrim-form on the winding core, whereby the risk of slippage of the at least one thread at the crossing points can be reduced, so that a precise position of the windings is ensured even after the connection or welding.

Preferably, the at least one thread in helixaufigen winding by means of a

Pretensioning device held under a defined bias, so that the at least one thread is stored in helixformigen winding with a defined bias on the previously deposited helical windings of opposite handedness.

According to a preferred embodiment of the invention, the winding core has a radial tensioning device, by means of which the finished tubular helix-shaped scrim is radially tensioned on the winding core. This has the advantage that the scrim can be re-tensioned, for example after thermosetting and / or before joining or welding, which can have a positive effect on the precision or the reproducibility.

The subject of the invention is also the stent. Accordingly, the stent comprises a tubular helix-shaped at least one thread, in particular a biaxial wound round clutch, or consists of the round clutch, the at least one thread being laid one above the other at points of intersection. The at least one thread or helixformigen windings are not intertwined, so it is not a braid.

Preferably, the at least one thread is wound in left-handed and right-handed helix-shaped windings which intersect at the crossing points, wherein the helixformigen windings are deposited at the crossing points in each case over the entire underlying helixformigen windings of each opposite handedness and are not intertwined with these in particular.

Accordingly, that portion of the at least one thread of all helical windings along the thread at least almost all - in the ideal case at all - successive crossing points of this helixformigen winding over the at least one thread extending transversely thereto with opposite handedness underlying helixformigen windings, each helical winding in its entirety lies completely radially over the entirety of the helical windings of the opposite handedness lying next to each other radially below it.

Preferably, the tubular helix-shaped wound scrim is axially delimited with at least a first axial end face open stent end, wherein

the at least one thread is wound in a first axial direction in either a left-handed or a right-handed helical first out-turn,

the same thread is loop-shaped at the front-side jacket edge of the tubular helix-shaped loop at the first axial end-side open stent end and

the same thread is wound in the second axial direction opposite to the helical first outward turn in a right-handed or left-handed helical first return turn, ie with the handedness opposite to the helical first turn, and at intersection points on the helix-shaped first outward turn is stored from the same thread. Preferably, the tubular helix-shaped wound clutch is axially bounded on both sides with a first and second axial end side open stent end, wherein the same thread helixformig wound, preferably several times, helixformig in the first axial direction and wound helixformig back in the opposite second axial direction and the same thread on the first and second axial end-side open stent end between the respective helix-shaped Hin-windings and helixformigen reverse windings is loop-shaped.

Thus, the stent, which is axially delimited on both sides, is formed, which is bounded by the loop-shaped deflections at the axial ends of the stent which are open at the end, which ensures a high level of protection against injury and radial expansion force.

In particular, therefore, the tubular helix-wound tissue is axially bounded on both sides with at least one first and second axial stent end open at the end, wherein the at least one thread is wound in a first axial direction in either a left-handed or a right-handed helical first out-turn,

the same thread is looped around the front-side jacket edge of the tubular helix-shaped wound jaw at the first axial end-face-open stent end,

the same thread is wound in the second axial direction opposite to the helical first outward turn in a left handed helical first reverse turn with the handedness opposite to the first helical first turn, and at intersections on the first helical first turn therefrom

Thread deposited radially from the outside - that is not intertwined - is,

the same thread is looped at the second axial end face open stent end and

the same thread is wound in the first axial direction in a helical second out winding having the same handedness as the helical first out winding and parallel to and adjacent to the helical first out winding and abutting

Crossing points on the helixformigen first return winding from the same thread radially stored from the outside - that is not intertwined - is.

According to a preferred embodiment of the invention, the same thread is helically wound several times helically in the first axial direction, open on the first axial end face

Stent end in the second axial direction looped deflected, wound helically in the second axial direction with opposite handedness and the second axial The stent end open at the end is in turn looped in the first axial direction, the same thread being deposited on each helix-shaped reverse coil on the previously generated helical outward turns of the same thread - ie not intertwined - and the same thread on each helix-shaped reverse coil on the previously generated helixformigen outward turns of the same thread stored - that is not intertwined - is, with the

loop-shaped deflections between the helix-shaped outward windings and the helical reverse windings form the first and second axial end-side open stent ends.

In other words, the helical winding windings winding by winding are placed side by side in parallel and the helical reverse windings are laid parallel to each other across the winding windings, alternately i) the respective helical reverse windings on the underlying windings helix-shaped forward windings; and ii) the respective helix-shaped forward winding is deposited on the underlying helix-shaped back windings.

In other words, a multiplicity of helical outward windings and return

Windings comprises, wherein the helix-shaped Hin-windings and helixformigen back windings alternately superimposed - so not intertwined - are.

Preferably, therefore, the same thread is wound back and forth many times and each helical winding is deposited at the intersection points on the underlying helical windings of opposite handedness.

In this case, a left-handed helical winding on a right-handed helix-shaped winding and then a right-handed helical winding on a left-handed helix-shaped winding etc. are preferably always alternately deposited.

According to a preferred embodiment of the invention, the at least one superposed thread is connected to at least some of the points of intersection, in particular with itself.

Preferably, the at least one superimposed thread at least some of the crossing points, in particular with itself, welded.

In particular, the at least one superimposed thread at several, but not at all crossing points, in particular with itself, connected or welded.

Preferably, the crossing points are connected or welded at regular intervals, for example every second, third, fourth or nth of the crossing points with respect to the Circumference and / or the central longitudinal axis of the particular cylindrical shape of the tubular helically wound Geleges.

To set the desired radial force of the tubular wound Geleges, it has proven to be advantageous if the proportion of connected or welded

Crossing points on the total number of crossing points in the range between 2.5% and 40%, preferably between 5% and 25%.

Preferably, the crossing angle of the at least one superposed thread at the crossing points in the range between 10 and 80 °, preferably in the range between 30 ° and 60 °.

According to a preferred embodiment of the invention, the tubular helix-wrapped scrim is heat-set.

A pulmonary stent is exposed to cyclic dilatations at the rate of respiratory rate and is compressed about 1-2 mm in diameter with a starting diameter of 8-12 mm. Upon coughing, significantly larger diameter reductions may occur, e.g. a Nitinol stent and a silicone coating can partially go along. Further areas of application for larger stents with similar requirements as in the trachea (neutral environment, pH ~ 7) are the esophagus, gall bladder and the gastrointestinal tract (pH up to 1). However, use for coronary stents is also possible.

The stent which can be produced according to the invention can therefore in particular comprise a blood vessel stent, e.g. a cardiac or coronary artery stent or stent, or pulmonary, tracheal, laryngeal, ureteral, gastrointestinal, or bile duct stents. Depending on the application different threads come into consideration.

Thus, the thread of a nickel-titanium alloy, of nitinol, of magnesium, of a magnesium alloy, of a medical grade stainless steel, a cobalt alloy, a chromium alloy, a cobalt-chromium alloy, from a niobium alloy, a tantalum alloy, a platinum alloy, a platinum-chromium alloy or a polymer. In the case of a metal thread, it is also possible to speak of a wire so that the stent consists of a tubular wire support structure.

Depending on the application, the at least one thread has a diameter in the range of 1 μιη to 400 μιη, preferably in the case of a blood vessel stent in the range between 10 μιη and

150 μιη and preferably in the case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stent in the range between 10 μιη and 300 μιη, on. Preferably, the at least one thread, or the helical windings of the tubular helical wound gel are at a distance in the range of 0.5 mm to 5 mm, preferably in the case of a blood vessel stent in the range between 0.5 mm and 2 mm and preferably in the case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stent in the range between 3 mm and 5 mm.

Depending on the application and the thread, the tubular wound scrim can each be in the range between 3 and 150 helical windings, preferably in the range between 12 and 60 helical windings in both axial directions, i. of both hands.

Depending on the application, the diameter of the tubular helical wound gel is in the range between 0.1 mm and 25 mm, preferably in the case of a blood vessel stent in the range between 0.1 mm and 10 mm, and preferably in the case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stents ranging between 5 mm and 25 mm.

In summary, the tubular helically wound scrim is in particular a monofilament, unwound and unblochten, biaxial, bilayer and / or by deflections of the, in particular a single, thread axially bounded on both sides, tubular helical wound round clutch.

In the following the invention with reference to embodiments and

Referring to the figures in more detail, wherein the same and similar elements are partially provided with the same reference numerals and the features of various embodiments and particular aspects or further developments of the disclosed embodiments of the invention can be combined with each other.

Brief description of the figures

Show it:

1 is a perspective view of a winding core,

2 is a radial side view of the front of the winding core of FIG. 1 with partially wound wire,

3 is a radial side view of the back of the winding core of FIG. 2,

Fig. 4 is a radial side view of the winding core of FIG. 2 with complete

wound yarn, forming the round-scrim according to an embodiment of the

Invention, 5 is a schematic view of the symbolically cut and unrolled lateral surface of the winding core to illustrate the yarn deposit,

Fig. 6 is a schematic representation of the round-Geleges on the winding core and a

heat setting,

Fig. 7 is a schematic representation of a section of the Geleges with some

Welds,

Fig. 8 is a photographic representation of an example of a winding core

wound up round-about,

9 is a scanning electron micrograph of a welded

Crossing point of a Nitinol wire of the round-pile of Fig. 8,

10A-C is a schematic side view of a Rund-Geleges when doubling the first helical Hin-winding for connecting the wire ends according to an embodiment of the invention,

11 is a schematic side view of three round-laid successively wound on the same winding core,

Fig. 12 is a schematic perspective view of a joining sleeve with finished

wound, but still unwelded circular clutch according to an embodiment of the invention,

13 is a schematic perspective view of a flexible joining sleeve with finished wound but still unwelded round clutch according to an embodiment of the invention,

FIG. 14 is a schematic representation of the local fixing of a crossing point for subsequent joining, FIG.

15 is a photo of a joining sleeve similar to FIG. 12, placed on a wound on the winding core circular clutch for joining or welding selective crossing points, Fig. 16 is a photo of a winding core with prefabricated storage grooves according to a

Embodiment of the invention,

Fig. 17 is a schematic view of a symbolically cut and unrolled

Omnidirectional with a predefined pattern of intersecting points according to an embodiment of the invention, 18A-D are schematic views of symbolically cut and unrolled rounds with various predefined patterns of intersecting points according to embodiments of the invention;

Fig. 19 is a photo of an exclusively wound filament stent without joined

Cross points and its deformation under radial load.

Detailed description of the invention

With reference to FIG. 1, a cylindrical winding core 12 having a lateral surface 12c and two end faces 12a, 12b which are axial with respect to the central axis of symmetry A is used. The winding core 12 is continued on both sides by a shaft 14. In the vicinity of the two end faces 12a, 12b extend from the lateral surface 12c radial

Deflection devices in the form of upper and lower deflecting pins USa, USb. The upper and lower deflecting pins USa, USb are arranged in a ring shape near both ends of the winding core 12 around the circumference of the circumferential surface 12c.

Referring to FIGS. 2-5, a single filament 22, in particular a metal wire, in this example in the form of a Nitinol wire with a wire diameter of 200 μm, is fastened to an initial fastening means in the form of a fastening pin 24 in this example , Subsequently, the winding core 12 is continuously rotated by means of the shaft 14 in one and the same direction R (see FIG. During rotation of the winding core 12, the yarn 22 is axially reciprocated, i. moved up and down in this example to wind it in evenly alternating opposite helical windings. For this, e.g. a converted rewinding machine can be used.

The thread 22 is initially passed by the initial attachment means 24 at an upper deflection pin US1a.

The thread 22 is then helically wound onto the winding core 12 with a first handedness in a first axial direction A1, in this example axially downwards in a first outward winding HW1, until the first outward winding HW1 is deflected about a lower deflection pin US1b becomes. Here, the thread 22 forms a lower loop-shaped deflection SU1 b.

Subsequently, under the same direction of rotation R of the winding core 12, the axial

Feed direction of the thread 22 reversed, so axially upward a first return winding Rewind RW1 helically in the opposite axial direction A2 and with opposite second handedness.

The first return winding RW1 is deposited at the rear side (FIG. 3) at a crossing point HW1 RW1 radially from the outside over the thread 22 of the first outward winding HW1, so that at this point the first return winding RW1 radially comes to rest outside the first turn HW1.

The first return winding RW1 is further stored again on the front side (FIG. 2) at a further crossing point HW1 RW1 with respect to the axis of rotation A radially from the outside over the thread 22 of the first outward winding HW1, so that at this point the first return winding Winding RW1 again comes to lie radially outside the first outward winding HW1.

Subsequently, the thread 22 is deflected by an upper deflection pin US2a adjacent to the upper deflection pin US1a, thereby forming an upper loop-shaped deflection SU2a.

By again reversing the axial feed direction of the thread 22, it is subsequently returned to the first axial direction A1, i. axially wound down in a second outward turn HW2 helically on the winding core 12 again with the first handedness.

The second outward winding HW2 is deposited on the rear side (FIG. 3) and on the front side (FIG. 2) at the rear and front crossing point RW1 HW2 radially from the outside on the first reverse winding RW1.

Subsequently, the second outward winding HW2 is deflected by a lower deflecting pin US2b. Here, the thread 22 forms a further lower schlingenformige deflection SU2b.

Subsequently, with further rotation R of the winding core 12 in the same direction, the axial feed direction of the thread 22 is reversed so as to wind back axially a second reverse winding RW2 helically in the opposite axial direction A2 and with the opposite second handedness.

The second return winding RW2 is deposited at the rear (FIG. 3) at intersection points HW1 RW2, HW2RW2 radially from the outside over the thread 22 of the first and second outward turns HW1, HW2, relative to the axis of rotation A, so that at these points the second Reverse winding RW2 radially outside of the first and second outward winding HW1, HW2 comes to rest. The second rewind winding RW2 is further stored again on the front side (FIG. 2) at further intersection points HW1 RW2, HW2RW2 with respect to the axis of rotation A radially from outside over the thread 22 of the first and second rewind HW1, HW2, so that these In turn, the second return winding RW2 comes to lie radially outside the first and second outward winding HW1, HW2.

Subsequently, the thread 22 is moved to the upper turning pin US2a

deflected adjacent upper deflecting pin US3a and thereby forms an upper loop-shaped deflection SU3a.

By reversing the axial feed direction of the thread 22, it is subsequently returned to the first axial direction A1, i. axially wound down in a third outward turn HW3 helically on the winding core 12 again with the first handedness.

The third outward winding HW3 is deposited on the rear side (FIG. 3) and on the front side (FIG. 2) at the rear and front crossing points RW1 HW3, RW2HW3 radially from the outside on the first and second reverse windings RW1, RW2.

Subsequently, the third outward winding HW3 is deflected by a lower deflecting pin US3b. Here, the thread 22 forms a further lower loop-shaped deflection SU3b.

Subsequently, with further rotation of the same direction R of the winding core 12, the axial feed direction of the thread 22 is reversed so as to wind back axially a third reverse winding RW3 helically in the opposite axial direction A2 and with the opposite second handedness.

The third return winding RW3 is deposited at the rear (FIG. 3) at points of intersection HW1 RW3, HW2RW3, HW3RW3 radially from the outside over the thread 22 of the first, second and third outward turns HW1, HW2, HW3 relative to the rotation axis A. that at these points the third reverse winding RW3 comes to lie radially outside the first, second and third outward windings HW1, HW2, HW3.

The third reverse winding RW3 is again front side (Fig. 2) at further crossing points HW1 RW3, HW2RW3, HW3RW3 relative to the axis of rotation A radially from the outside over the thread 22 of the first, second and third outward winding HW1, HW2, HW3 stored so that at these points the third return winding RW3 again comes to lie radially outside the first, second and third outward winding HW1, HW2, HW3. Subsequently, the thread 22 is moved to the upper turning pin US3a

deflected adjacent upper deflecting pin US4a and thereby forms an upper loop-shaped deflection SU4a.

This reversed winding of the thread 22 is continued until the wire 22 has been deflected about all the upper and lower deflection pins USa and USb, forming the complete tubular helix-wound biaxial two-ply round fabric 30 shown in FIG. Here are the upper and lower loop-shaped

Deflectors SUa, SUb the upper and lower open stent end 34a, 34b and the respective axial edge of the shell of the round-Geleges 30th

The laying pattern of the front side (FIGS. 2, 4, 5) and rear side (FIGS. 3, 5) show that the tubular support structure produced in this way is a scrim and not a braid.

It can be seen that the entirety of the deflecting pins short with USa, USb, the

Total of the loop-shaped deflections short with SUa, SUb, the entirety of the forward windings short with HW, the entirety of the rear windings short with RW and the entirety of the crossing points of forward and reverse windings or vice versa short with HWRW, RWHW resp 31, 32.

In the present example is a made of a single thread 22, thus monofilament, tubular helix wound round-scrim 30, wherein each winding HW, RW is wound by about 360 ° around the winding core 12, so that the respective upper and lower loop-shaped deflection SUa, SUb, which each winding HW, RW bounded on both sides, are approximately at the same angular position (shifted by the respective angular feed of winding to winding). However, it is also possible for each winding to rotate only by a smaller angle of rotation, e.g. about 180 ° to wrap the winding core 12 or by a larger angle of rotation, e.g. two turns, i. about 720 °, or more or less to wind up. The filing at the intersection points thus generated results accordingly.

With the choice of winding parameters, e.g. the angle of rotation, the desired properties of the final tubular helix-wound circular scrim may be manipulated to make it e.g. to adapt to the desired application.

FIG. 5 again shows the sequence of the first and second outward turns and first and second backward turns in a schematically unrolled representation. Referring to FIG. 6, the finished tubular helically wound lap fabric 30 is heat set in a heat setting unit 40 at about 350 ° to 650 ° for about 2 to 15 minutes to affect the tension of the still unwelded lap 30. As a result, during the subsequent welding of the crossing points, it can be prevented that the wire slips at the crossing points 32 to be welded, which contributes to a higher precision.

The winding core 12 further has a radial tensioning device 44, in this example such that the winding core 12 consists of two halves 12a, 12b, which can be pressed apart, in particular after winding and / or after heat-setting, on the winding core 12 rewind wound round-clutches 30.

Referring to Fig. 7, when the tubular helical wrapped scrim 30 is finished wound, selected intersection points 32 are joined together, in this example, welded. In this example there are eight welded crossing points 32, which are selected according to a predetermined pattern, in the present example from left to right as a 2-0-4-0-2 sequence. By means of the number and positioning of the welded crossing points 32, the mechanical properties, e.g. the radial force, flexibility and / or flexibility can be adjusted to the desired requirements. The stent 34 is thus formed by the fully wound round-scrim 30.

Thus, although a plurality or plurality of crossing points are welded, but not all. There are therefore both unwelded crossing points 31 and welded crossing points 32. In particular, as many as necessary, but as few as possible crossing points are welded together. Thereby, a stent 34 is made from the tubular completely helically wound round fabric 30, which has a good radial force but is nevertheless not excessively stiff but flexible. A stent 34 produced in this way is in particular compactable and can be adapted to the vessel geometry.

Furthermore, the two terminating ends of the thread 22 are still attached to the scrim 30, e.g. welded.

Referring to FIG. 8, a prototype of the tubular helical wound lap 30 is shown as being made of a nitinol wire having a wire diameter of 200 μm and a diameter of the lap 30 of approximately 1.5 cm. In this example, the

Crossing angle at the crossing points about 60 °. It was resorted to a winding core 12, which was designed for the manual production of a braided filament stent 34. On top of that were the windings

performed. It has been shown that with the deflecting pins USa, USb a defined storage location for the thread or wire 22 is provided on the winding core 12, which is advantageous in order to avoid slippage. Furthermore, the thread or wire 22 is deposited with a defined pretension in order to ensure a mechanical contact of the crossing thread or wire 22 at the intersection points 32 to be welded. In addition, 22 is prevented from slipping on the winding core 12 by the bias of the thread or wire.

As schematically shown in Fig. 5, the wire 22 is replaced by a tensioning device

42, e.g. comprising a spring, held during winding on the winding core 12 under a defined bias.

For guiding the thread or wire 22 along the winding core structure, a precise deflection on the deflecting pins USa, USb of the two stent ends 34a, 34b is ensured.

Welding investigations have shown that a crossed nitinol

Wire with a diameter of 0 = 200 μιη can add using the micro-electron beam welding and thereby a sufficiently high

Bond strength can be achieved. The connection at the point of intersection 32 of the crossing Nitinol wire 22 may be determined by parameters such as e.g. Beam positioning,

Focus diameter, wire bias, etc. are set.

Referring to Fig. 9, there is shown a welded crossing point 32, which has been correspondingly welded by electron beam technique. Here, a beam current of 0.13 mA, an acceleration voltage of 60 kV, a focus diameter of about 50-100 μιη and a pulse duration of 400 ms to 500 ms was used. The electron beam is preferably not perpendicular in the radial direction, but obliquely, ie with an axial

Direction component directed to the intersection points 32 to be welded to the contact surface between the superimposed wire sections precisely

melt and weld. The thread sections are directly welded together, i. no filler metal is used (DIN 1910-100: 2008-02).

The present example in Figs. 8, 9 shows a prototype of a self-dilating one

Tracheal stents. However, it is also possible to produce balloon-dilating cardiac stents or other stents if the process parameters are adapted accordingly. To adapt to the particular area of use of the stent 34 is adapted accordingly to one or more of the following parameters:

Material of the thread 22,

Diameter of the thread 22,

Angle of rotation of the windings HW, RW between the deflection devices USa, USb,

Diameter of the winding core 12,

Number of welded crossing points 32,

Number of unwelded crossing points 31,

Arrangement and / or ratio of the number of welded and unwelded crossing points 32, 31, and / or

Crossing angle of the thread at the crossing points 32, 31.

Depending on the material and diameter of the thread, the joining method and the process parameters of the respective joining method, e.g. when electron beam welding, the beam current, focus diameter, etc., to be adjusted. For example, can by means of

Laser beam welding in particular also non-conductive threads, e.g. be welded from plastic. From today's perspective, the complexity of the braiding process makes it difficult to automate the manual process of making a hand-braided stent. However, with the present invention, a similar suture support structure can be made as in a hand-braided stent, i. in particular, a single-thread stent 34, in which a single (or possibly also some threads) is looped at both axial stent ends 34a, 34b, but in contrast to the hand-braided stent, the thread or the helical windings not braided, but instead is successively deposited on each other by winding. In other words, due to the

Winding process another thread guide course without the hand-alternating alternating over and underpass of the wire or thread selected. In order nevertheless to achieve the desired stability, this is supported, in particular, by defined intersecting points of intersection, in particular welding points, at selected crossing points 32. This may approximate the structure of the hand-braided stent and still allow a mechanized or automated process. There are the disadvantages of

hand-braided stents, ie high working time and poor reproducibility eliminated. The result is a stent structure that can run automatically at least in the two sections of the process of winding and welding. It is not necessary that the tubular biaxial detach helically wrapped scrim from the hub before the welding process is complete. It can therefore be wound on the same core 12 and welded. It is advantageous if the core 12 can be easily and quickly mounted in the technical joining system.

The stent 34 made using the present invention is a medical

Implant or an endoprosthesis, in which or in particular a single thread or wire 22 helically wound around a cylindrical winding core 12 by means of deflection pins USa, USb. By the deflection pins USa, USb at the axial ends of the cylindrical winding core 12, the thread or wire 22 can be deflected and tensioned.

Winding parameters, such as the thread or wire distance can be adjusted. Since the thread or wire 22 is not interlaced and intertwined with each other, but only repeatedly wound or stored on top of each other, according to a selected pattern corresponding connection or welding points at the intersection points 32 are prepared. The connection or welding points are selected in particular in such a way that a homogeneous cohesion of the implant is ensured, the required radial rigidity is achieved and at the same time a sufficiently high axial bending is made possible. In the case of a single thread stent, only the two ends of the thread are to be closed, which is likewise done with the aforementioned joining or welding methods in one step with the welding of the selected ones

Intersection points 32 can be made.

Figures 10A-10C show an embodiment of a tubular helically wound one

Single thread lap 30 and a method for improved closing of the two terminating ends 22a, 22b of the thread 22. For this purpose, the first helical outward turn HW1 is doubled. More specifically, the first helical out-turn HW1 at the end of

Winding process or after the deposition of the otherwise last helixformigen winding doubled by after the deposition of the otherwise last helixformigen winding immediately next to and / or parallel to the first helically deposited Hin-winding HW1 an additional helical out-winding HW1Z is stored.

Referring to FIG. 10A, which shows the already doubled first helical turn HW1, first the beginning 22a and the end 22b of only one thread 22 in this example are fixed axially outward of the lap 30 by a clamping device 24a.

Referring to Fig. 10B, the two parallel juxtaposed portions of the doubled yarn 22 become subsequent to the first helical turn HW1 joined together, for example, materially joined together, in particular welded together. However, there are also non-positive or positive connections possible, such as crimping. The join or weld is preferably made at a cross point 32 along the doubly routed first and second auxiliary helical turn, with an existing helical return coil present. Subsequently, for example by the welding tool, ie in the same manufacturing process on the winding core 12, the protruding free ends of the thread 22 are separated, for example thermally.

With reference to FIG. 10C, therefore, a joint, in this example a material fit, remains between the two ends 22a, 22b of the thread 22, in particular at an intersection point 32 of the loop. Thus, the thread 22 extends in an endless orbit around the winding core 12. It is therefore a, in this example cohesive, joint, e.g. created a welding point, which connects the ends 22a, 22b of the thread 22 directly to each other and at the same time at the endless connection point of the ends 22a, 22b forms a mating crossing point 32. The result is a single-thread stent 34 from a self-contained endlessly closed (non-braided) single-thread 22nd

With reference to FIG. 11, two, three or more stents 34 can be manufactured on one and the same winding core 12 directly from one and the same initially uncut thread 22.

In the winding device shown, for example, three stents 34

manufacture side by side on the same winding core 12. First, a first, in particular monofilament tubular helically wound round fabric 30 'is deposited on an upper first region 12' of the winding core 12, in this example with doubling of the first helically deposited reverse winding HW1, as described with reference to FIGS. 10A-10C , Subsequently, the same thread 22 is transferred into a central second region 12 "of the winding core 12 and there completely wound a second, in particular single-thread tubular helical wound round fabric 30", in this example with doubling of the first helically deposited turn HW1, as described of FIGS. 10A-10C. Subsequently, the same thread 22 is further transferred to a lower third region 12 "'of the winding core 12 and there completely wound a third, in particular single tubular helical wound round fabric 30"', in this example with doubling of the first helically deposited Hin-winding HW1 as described with reference to Figs. 10A-10C. For this purpose, the winding core 12 has three pairs of Deflection pins USa, USb on. Finally, the wire end is fixed with a clamping device 24a. Thereafter, the three round layers 30 ', 30 ", 30"' deposited side by side on the same winding core 12 are heat-set, subsequently joined, in particular welded. In this case, the endless connections of the thread 22 of the three stents 34 ', 34 ", 34"' can be joined and the three stents separated from each other.

Referring to Figs. 12-15, methods and means for improving the joint at the crossing points 32 will be described. The touch of the

superimposed thread 22 within a crossing point 32 is particularly for non-contact joining methods, such. the beam welding process, important for a successful joint connection.

The joint connection can be improved if the thread 22 crossing over at the points of intersection 32 actually touches during joining or welding and, if necessary, is pressed against one another with a minimum radial force. This can be achieved either by an internal radial tensioning device 44, as shown schematically in FIG. 6, or by an external joining sleeve 46, which is slipped over the round scrim 30 deposited on the winding core 12 and radially onto the circular scrim 30 pushes the thread 22 to the

Crossing points 32 with a minimum radial force to press each other.

The joining sleeve 46 may be solid, e.g. be made of two halves 46a, 46b (see Fig. 12) or flexible (see Fig. 13). The flexible joining sleeve 46 in Fig. 13 is e.g. from a flexible hose 48. In both cases, the joining sleeve 46 openings 50, through which the thread 22 of the underlying round-Geleges 30 can be joined. For example, For example, in Fig. 12, the two ferrule halves 46a, 46b have bores 50 through which the welding energy, e.g. a laser or electron beam can be directed onto the intersection points 32 to be joined (compare FIGS. 12, 15). The joining sleeve 46 embodied as a tube 48 has, for example, a net-like structure, so that it can also be joined here through the cutouts 50 in the net-like structure.

Referring to FIG. 14, local radial application of force to the intersecting thread 22 at individual intersection points 32 to be joined is also possible. For this purpose, a radial force is exerted on a junction point 32 to be joined with a pressing tool 52 when it is joined.

Referring to FIG. 16, the winding core 12 may have prefabricated storage grooves 54 in which the yarn 22 is deposited during winding. The thread 22 can thereby be stored more precisely, since he on the winding core 12 through the net-like crossed

Shelf grooves 54 is held better in position.

Referring to Figs. 17 and 18A-18D, an example of the lay-flat filament stent 34 comprised of the circular scrim 30 has the following specifications:

Stent length: 30 mm

Stent diameter: 15 mm

Wire thickness: 200 pm

Winding angle (angle between wire and axle of the winding core): about 66 °

Mesh size: 2.4 mm

Mesh height: 3.93 mm

For this present geometry, a number of mating intersections 32 between 8 to 12 intersection points per stent 34 is sufficient to achieve the maximum radial force of a comparable braided monofilament stent. The radial strength can be increased by increasing the number of intersecting points 32, taking care not to restrict the flexibility (crimping properties) too much despite increasing the radial strength. Therefore, the number of joined crossing points 32 should also not be too large. Therefore, the number of joined

Junction points 32 chosen as a compromise depending on the desired radial strength and flexibility. In this case, besides the number of intersecting points 32, the arrangement of the intersecting points 32 connected via the stent geometry is decisive. The jointed points 32 in the edge area of the stent structure have a particular influence on the crimping properties. In addition, this results in a lower local deformation of the structure under the effect of a punctual load, both in the edge region and in the middle of the structure instead. If no joint points are set, a radial displacement of the stent structure in the middle may occur in the case of a radial load, as can be seen in FIG. 19.

Furthermore, an arrangement symmetrical to at least one level of advantage to evenly distribute the radial force on the stent 34 and protect individual welds against overload. In addition, as many different crossing back and forth windings HW, RW can be connected to each other (see Fig. 17). This may be the slipping of the

Restrict the thread 22 at the ungüften crossing points 31 and so increase the radial force. Referring again to Figures 17 and 18A-18D, further examples of patterns for the intersecting points 32 are shown. In this case, the joined crossing points 32 can be offset axially and / or circumferentially relative to each other.

In the example shown in Fig. 17, adjacent mated crossover points 32 are axially offset by one intersection point and circumferentially by two crossing points, respectively, and two lines of mated crossover points 32 (eg, 2 x 6) are formed near the two stent ends 34a, 34b ,

In the examples shown in Figs. 18A-18D, 12, 10, 8 and 9, respectively, are joined

Crossing points 32 provided on a plurality of perpendicular or oblique to the axis of the winding core 12 extending straight lines.

The stent may meet the following specifications depending on the application:

Stent length: between 10 mm and 60 mm,

Stent diameter: between 3 mm and 30 mm,

Wire thickness: In the range of 1 μιη to 400 μιη, in the case of a blood vessel stent preferably in the range between 10 μιη and 150 μιη and in the case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stent preferably in the range between 10 μιη and 300 μιη,

Winding angle: between 30 ° and 75 °,

Mesh size: Between 1 mm and 6 mm, and / or

Mesh height: between 1 mm and 6 mm.

By the invention disclosed herein, the hand braiding of finished preconfigured stents can be replaced by an automated wrapping and welding process and thus the

Time expenditure can be significantly reduced. In addition, due to the reduction of manual work, a significant cost reduction can be expected. Furthermore, this type of production further automates the process and ensures reproducibility. Production in environments with higher wage structure may be possible.

It will be apparent to those skilled in the art that those described above

Embodiments are to be understood as exemplary and the invention is not limited to these, but can be varied in many ways, without departing from the scope of the claims. It can also be seen that the characteristics, irrespective of whether they are in the

It is also intended that the specification, claims, figures or otherwise be disclosed, also individually define essential components of the invention, even when combined with others Characteristics are described together and that features disclosed in connection with the manufacturing process are considered to be revealed even for the manufactured stent and vice versa.

Claims

claims:

A method of manufacturing a stent (34) comprising the steps of:

Providing a winding core (12),

helical winding at least one thread (22) on the winding core (12), wherein upon winding on the winding core (12) of the at least one thread

Crossing points (31, 32) is placed over one another crosswise, so that a tubular helically wound scrim (30) from the at least one thread (22) is formed on the winding core,

Separating the tubular helically wound web (30) from the

Winding core (12).

2. The method according to claim 1,

wherein the winding core (12) has at least at a first axial stent end (34b) to be produced first deflecting devices (USb) for the at least one thread (22) and

a1) the at least one thread (22) is wound onto the winding core (12) in a first axial direction (A1) in either a left-handed or a right-handed helical first forward turn (HW1),

a2) then the same thread (22) from step a1) at the first axial end face open stent end to be generated around one of the first

Deflection devices (USb) is looped and looped

a3) subsequently the same thread (22) from step a2) in the second axial direction (A2) opposite to step a1) is wound onto the winding core (12) in a helical first reverse winding (RW1) with the handedness opposite to step a1) and is deposited at intersection points (31, 32) on the helical first outward winding (HW1) from the same thread (22).

3. The method according to claim 2,

wherein the steps a1) to a3) are performed several times and by the loop-shaped deflection of the at least one thread (22) to the first

Umlenkeinrichtungen (USb) first loop-shaped deflections (SUb) from the At least one thread (22) is formed between the helical outward turns (HW) and the helical outward turns (RW), so that the tubular helix-shaped loop (30) is already wound up during winding of the at least one thread (22) through the first loop-shaped Deflections (SUb) between the helix-shaped outward windings (HW) and the helix-shaped rear windings (RW) axially limited with at least a first axial end face open stent end is generated.

Method according to one of the preceding claims,

wherein the winding core (12) at a first axial stent end (34b) to be produced first deflecting means (USb) and at the second axial stent end (34a) opposite the first axial stent end to be produced second deflecting means (USa) for the at least one thread (USa) 22) and

a1) the at least one thread (22) is wound on the winding core (12) in a first axial direction (A1) in either a left-handed or a right-handed helical first turn (HW1),

a2) subsequently the same thread (22) from the step a1) is looped around the first axial end face open stent end (34b) around one of the first deflection devices (USb),

a3) subsequently the same thread from step a2) in the second axial direction (A2) opposite to step a1) in a helical first reverse winding (RW1) having the handedness opposite to step a1), to which

Winding core (12) is wound up and is deposited at intersection points (31, 32) on the helix-shaped first outward winding (HW1) from the same thread,

a4) subsequently the same thread (22) from the step a3) is looped around the loop at one of the second deflection devices (USa) at the second axial end face open stent end (34a) and

b1) subsequently the same thread (22) from the step a4) in the first axial direction (A1) in a helical second outward turn (HW2) with the same handedness as in step a1) is wound onto the winding core (12) and thereby

Crossing points (31, 32) on the helixformigen first reverse winding (RW1) from the same thread (22) is stored. Method according to claim 4,

wherein the steps a1) to a4) are performed a plurality of times in succession, wherein the at least one thread (22) at each helical rewinding (RW) on the previously generated helix rewinds (HW) of the same thread (22) and the same thread at each helical reverse winding (RW) is deposited on the previously formed helical outward turns (HW) of the same thread to produce the tubular helically wrapped scrim (30) and wherein the looping deflection of the at least one thread on the first deflection means (30) USa) first schlingenformige deflections (SUa) from the at least one thread (22) between the helix Hin-windings (HW) and the helixformigen reverse windings (RW) and by the Schlingenformige deflecting the at least one thread (22) to the second Deflectors (USb) second schlingenformige deflections (SUb) from the at least one thread (22) between the helixform reverse windings (RW) and the helixformi Hin-windings (HW) arise, so that the tubular helically wound scrim (30) already during winding of the at least one thread (22) by the first and second loop-shaped deflections (SUb, SUa) between the helix-shaped Hin windings (HW) and the helix-shaped back windings (RW), or between the helix-shaped back windings (RW) and the helical windings (HW), is axially limited on both sides with a first and second axial end face open stent end.

Method according to one of the preceding claims, comprising the following step:

Connecting the at least one yarn laid over one another during winding on at least some of the points of intersection (32).

Method according to one of the preceding claims, comprising the following step: cohesive joining, in particular welding, soldering or gluing the at least one superimposed upon winding filament (22) at at least some of the crossing points (32).

Method according to claim 7,

wherein the welding of the crossing points means Electron beam welding, laser welding, resistance welding, friction welding or micro-plasma welding is performed.

9. The method according to any one of the preceding claims,

wherein the at least one superimposed thread (22) is connected or welded at several, but not at all crossing points.

10. The method according to any one of the preceding claims,

wherein the proportion of connected crossing points (32) in the total number of crossing points (31, 32) ranges between 2.5% and 40%, preferably between 5% and 25%.

11. The method according to any one of the preceding claims,

wherein the at least one thread at the crossing points (31, 32) at a crossing angle in the range of 10 ° to 80 °, preferably in the range of 30 ° to 60 ° is superimposed.

12. The method according to any one of the preceding claims,

wherein the tubular helically wound scrim (30) is heat set on the winding core (12) in a heat setting unit (40) before the at least one superimposed thread (22) is joined at at least some of the points of intersection (32) and / or before the tubular becomes helical wound scrim (30) is separated from the winding core (12). 13. The method according to any one of the preceding claims,

wherein the at least one thread (22) is held by a biasing device (42) under a defined bias in the helical winding, so that the at least one thread in helixaufigen winding with the defined bias on the previously deposited helical windings (HW, RW) opposite handedness is filed. 14. The method according to any one of the preceding claims,

wherein the winding core (12) has a radial tensioning device, by means of which the finished tubular helix-shaped wound scrim is radially tensioned on the winding core.

15. The method according to any one of the preceding claims,

wherein the first helical out-turn (HW1) is doubled at the end of the winding process. 16. The method according to any one of the preceding claims,

wherein the at least one thread (22) of the tubular helix-shaped loop (30) has two thread ends (22a, 22b) which, in particular at an intersection point (32), are joined together to form an endless thread. 17. The method according to any one of the preceding claims,

wherein some of the intersections (32) are joined and pressed together when joining the thread (22) at the intersections (32), in particular by means of a joining sleeve (46) or a joining tool (52), radially. 18. The method according to any one of the preceding claims,

wherein a plurality of tubular helix-shaped laid scrim (30) from the same thread (22) are placed side by side on the same winding core (12).

19. The method according to any one of the preceding claims,

wherein the winding core (12) has shelf grooves (54) for depositing the at least one thread (22).

20. Stent (34), in particular producible according to one of the preceding claims, comprising a tubular helix-shaped wound from at least one thread scrim (30), wherein the at least one thread (22) at intersection points (31, 32) is superimposed. 21 stent (34) according to claim 20,

wherein the tubular helically wound scrim (30) is axially delimited with at least a first axial end face open stent end (34b), wherein

the at least one thread (22) is wound in a first axial direction (A1) in either a left handed or a right handed helical first turn (HW1),

the same thread (22) is loop-shaped at the first axial end face open stent end (34b) and

the same thread in the helix-shaped first turn (HW1)

in the opposite second axial direction (A2) in a helical first rewinding (RW1) having the opposite handedness to the helical first outward turn (HW1), and at intersection points (31, 32) on the helical first outward turn (HW1) the same thread (22) is stored.

22. Stent (34) according to one of claims 20 or 21,

wherein the tubular helically wound scrim (30) is axially bounded on either side with first and second axial end-side open stent ends (34a, 34b), the same thread (22) helically wound in the first axial direction (A1) and axially opposed in the second axial direction (A1) Direction (A2) helically wound back and the same thread (22) at the first and second axial end-side open stent end (34b, 34a) is looped between the respective helix-shaped Hin-windings (HW) and helixform reverse windings (RW).

23. stent (34) according to any one of claims 20 to 22,

wherein the tubular helically wound scrim (30) is axially delimited on both sides with at least a first and a second axial end face open stent end (34b, 34a), wherein

the at least one thread (22) is wound in a first axial direction in either a left-handed or a right-handed helical first turn-around (HW1),

the same thread (22) is looped at the first axial end face open stent end (34b), the same thread (22) is wound in the second axial direction (A2) opposite the helical first outward turn (HW1) in a helical first reverse turn (RW1) with the hand opposite the helical first turnout (HW1), and at crossing points (31, 32) is deposited on the helix-shaped first outward winding (HW1) from the same thread (22)

the same thread (22) is looped at the second axial end face open stent end (34a) and

the same thread (22) is wound in the first axial direction (A1) in a helical second outward turn (HW2) with the same handiness as the helical first turnout (HW1) and at intersection points (31, 32) on the helixforming first return winding (RW1) from the same thread (22) is stored.

24. stent (34) according to claim 23,

wherein the same thread (22) is helically wound several times in the first axial direction (A1), looped in the second axial direction (A2) at the first axial end side open stent end (34b), and helically in the second axial direction (A2) with opposite hand is rewound and at the second axial end-side open stent end (34a) turn looped in the first axial direction (A1), wherein the same thread (22) at each helixaufwicklung (RW) on the previously generated helix-shaped forward windings (HW) of the same thread (22) and the same thread (22) is deposited at each helical rewinding (RW) on the previously generated helical outward turns (HW) of the same thread (22), wherein the loop-shaped deflections (SUa, SUb) between the helix-shaped Hin - Windings (HW) and the helical Rück-windings (RW) form the first and second axial frontally open stent ends.

25. Stent (34) according to claim 24,

wherein the helix-shaped forward windings (HW) winding for winding are stored side by side in parallel and the helixform reverse windings (RW) are laid parallel to each other across the windings (HW) parallel to each other and alternately i) the respective helical return Winding (RW) on the underlying helical outward turns (HW) and ii) the respective helical outward turns (HW) Winding (HW) on the underlying helixformigen reverse windings (RW) are stored.

26. stent (34) according to any one of claims 20 to 25,

wherein the at least one superposed thread (22) at at least some of the crossing points (32), in particular materially connected, is connected.

27. Stent (34) according to one of claims 20 to 26,

wherein the at least one superposed thread (22) is welded to at least some of the crossing points (32).

28. Stent (34) according to one of claims 20 to 27,

wherein the at least one superimposed thread (22) is connected or welded at a plurality, but not at all crossing points.

29. stent (34) according to claim 28,

30. stent (34) according to any one of claims 20 to 29,

wherein the crossing angle of the at least one superimposed thread (22) at the crossing points (31, 32) in the range between 10 and 80 °, preferably in the range between 30 ° and 60 °.

31. stent (34) according to any one of claims 20 to 30,

wherein the tubular helically wrapped scrim (30) is heat set.

A stent (34) according to any one of claims 20 to 31,

wherein the at least one thread (22) is selected from the following group of threads:

Thread made of a nickel-titanium alloy, Nitinol thread,

Thread made of magnesium or a magnesium alloy

Thread made of a medical grade stainless steel,

Cobalt alloy thread,

Thread of a chrome alloy,

A cobalt-chromium alloy thread,

Thread of a niobium alloy,

Thread of a tantalum alloy,

Thread of a platinum alloy,

Thread made of a platinum-chromium alloy, - polymer thread.

A stent (34) according to any one of claims 20 to 32,

wherein the at least one thread (22) has a diameter in the range of 1 μιη to 400 μιη, preferably in the case of a blood vessel stent in the range between 10 μιη and 150 μιη and preferably in the case of pulmonary, tracheal, laryngeal, ureteral, gastrointestinal - or bile duct stents in the range between 10 μιη and 300 μιη, having.

A stent (34) according to any one of claims 20 to 33,

wherein the at least one thread (22) of the tubular helically wound pad (30) is spaced 0.5 mm to 5 mm, preferably in the case of a blood vessel stent in the range 0.5 mm to 2 mm and preferably in the Case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stent ranging between 3 mm and 5 mm.

A stent (34) according to any one of claims 20 to 34,

wherein the tubular wound scrim (30) each in the range between 3 and 150 helixformigen windings, preferably in the range between 12 and 60 helixformigen windings (HW, RW) in both axial directions. 36. stent (34) according to any one of claims 20 to 35,

wherein the diameter of the tubular helically wound pad (30) ranges between 0.1 mm and 25 mm, preferably in the case of a blood vessel stent in the Range between 0.1 mm and 10 mm, and preferably in the case of a pulmonary, tracheal, laryngeal, ureteral, gastrointestinal or bile duct stent in the range between 5 mm and 25 mm.

A stent (34) according to any one of claims 20 to 36,

wherein the two thread ends (22a, 22b) of the at least one thread (22) of the tubular helix-shaped loop (30), in particular at a crossing point (32), are joined to one another such that the at least one thread (22) forms an endless thread.