DE102020109158A1 - Medical intravascular treatment device and manufacturing process - Google Patents

Abstract

The invention relates to a medical device for intravascular treatment with an at least partially tubular lattice structure (10) made up of integrally interconnected webs (28), the lattice structure (10) having a web extension (11) at a proximal end section (10b) which has a Comprises engaging element (12). The engagement element (12) is connected to a distal coupling piece (14) of a transport wire (15) by a form-fitting connection. According to the invention it is provided that the coupling piece (14) has at least one projection (16) and the engagement element (12) has at least one recess (17), the projection (16) engaging in the recess (17) of the engagement element (12). The invention also relates to a manufacturing method.

Description

The invention relates to a medical device for intravascular treatment according to the preamble of claim 1 and a manufacturing method. A medical device of this type is made of, for example DE 10 2018 107 594 A1 known.

The end DE 10 2018 107 594 A1 known thrombectomy device, also referred to as a stent retriever, is suitable for rapid recanalization and has a hybrid cell design. This achieves excellent wall apposition and thrombus integration.

The thrombectomy device consists of a tubular lattice structure with bars delimiting individual cells. Such lattice structures are usually laser cut from a shape memory material such as nitinol.

The proximal end of the lattice structure is connected to a distal end of a transport wire. The connection consists of a form-fitting connection in which the ends of the components to be joined (stent component and transport wire) are interlocked and secured by a crimp sleeve that encompasses the joint.

In the DE 10 2018 107 594 A1 The form-fit connection described has proven itself in previous practice for the use of medical devices in 0.021 "catheters with an inner lumen of 0.530 mm. However, medical devices with such a form-fit connection have limited applicability.

The invention is based on the object of specifying a medical device for intravascular treatment, the possible uses of which are expanded without the functional reliability of the device being significantly impaired. Furthermore, the object of the invention is to provide a method for producing such a device.

According to the invention, this object is achieved with regard to the medical device by the subject matter of claim 1 and with regard to the manufacturing method by the subject matter of claim 24.

Specifically, the object is achieved by a medical device for intravascular treatment with an at least partially tubular lattice structure made of webs connected to one another in one piece, the lattice structure having a web extension at a proximal end section which comprises an engagement element. The engagement element is connected to a distal coupling piece of a transport wire by a form-fitting connection.

According to the invention it is provided that the coupling piece has at least one projection and the engagement element has at least one recess, the projection engaging in the recess of the engagement element.

The advantage of the invention is that, due to the positive engagement of the projection in the recess of the engagement element, a sufficiently strong connection is created between the stent component and the transport wire, so that no additional securing is required directly at the connection point itself. The strong connection makes it possible to flexibly arrange possible additional securing elements for fixing the connection point.

In general, it is pointed out at this point that the medical device has a tubular lattice structure which is radially expandable. The tubular lattice structure can automatically be converted from a radially compressed to a radially expanded state, for example by utilizing the shape memory effect. In this respect, the medical device preferably has a self-expanding lattice structure. The lattice structure can be designed in sections or completely tubular.

If the medical device is configured as a thrombectomy device, it can be provided in a preferred manner that the lattice structure is tubular in sections, the tubular shape merging into a funnel-shaped or conical section at a proximal end of the lattice structure.

It is further pointed out that in the context of the present patent application the term “distal” means a side of the lattice structure facing away from the user of the device or a side that is remote. The term "proximal" means a side of the medical device facing the user, i.e. a side closer to the user.

Preferred embodiments of the invention are specified in the subclaims.

In a preferred embodiment, the recess is designed to be closed, the recess extending essentially in the axial direction of the engagement element. Due to the closed design of the recess, the projection and the recess are over the entire Circumference in engagement, so that greater forces can be transmitted.

In order to achieve a high degree of design diversity in the manufacture of the medical device, the recess preferably corresponds essentially to the contour of the engagement element. For example, it is provided that the engagement element has a rectangular contour, so that the recess also has a rectangular contour, the recess comprising at least two sides which are arranged opposite one another.

In a preferred embodiment, the coupling piece has at least two projections which are designed as transverse anchors. By means of the projections, the proximal end of the lattice structure is positively connected or can be connected to the distal end of the transport wire, more precisely, the engagement element to the coupling piece. A projection is sufficient to ensure a form-fitting connection. The formation of at least two projections in the form of a transverse anchor has the advantage that an even more secure connection between the lattice structure and the transport wire is created and a symmetrical introduction of force is made possible. As a result, the connection is strong enough to be able to transmit the forces that occur. This embodiment is particularly suitable as a thrombectomy device.

During the treatment, especially when the medical device is to be withdrawn into a delivery system, for example a catheter, after a positioning attempt, forces, in particular tensile and compressive forces in the axial direction related to the coupling piece, as well as bending and torsional forces occur. In order to enable a uniform, in particular symmetrical transmission of these occurring forces, namely in such a way that a sufficiently secure axial fixation of the coupling piece is also ensured, the transverse anchor is preferably designed as a T-anchor. Furthermore, a T-anchor can be produced easily.

In a further preferred embodiment, the projection corresponds to the shape of the recess. This means that the recess has essentially the same shape as the projection, in particular shows the corresponding negative shape. This has the advantage that the projection can be arranged precisely in the recess. In this way, the transport wire can be adapted to almost any stent structure, so that a flexible or high level of design variety is achieved in the manufacture of the medical device.

In principle, the recess can extend both in the axial and in the vertical direction of the engagement element. However, since the greatest forces occur in the axial direction in relation to the coupling piece, the projection and the recess preferably extend essentially in the axial direction of the engagement element.

In order to be able to feed the medical device into relatively small delivery systems, in particular into a 0.017 "catheter with an inner lumen of 0.420 mm, the lattice structure is compressed to a relatively small cross-sectional diameter Connection is secured, arranged axially one behind the other or distally and / or proximally to the joint, for which purpose a plurality of axially adjacent sections are preferably provided on the coupling piece, each of which has different outer diameters.

The crimp sleeve does not directly encompass the joint or the form-fitting connection, but is arranged either distally and / or proximally to it. For this purpose, a first section is preferably arranged directly distal and a second section directly proximal to the projection. The second section can have a larger outer diameter than the first section.

In a further preferred embodiment, a third section is arranged immediately distal to the first section. The third section can have a larger outer diameter than the first section, the width of the two sections being the same. The third section can have an elevation so that the third section forms an abutment for the crimping, on which the crimp barrel rests. The third section can have the same outer diameter as the first section.

In a further preferred embodiment, a fourth section is arranged immediately proximal to the second section. The fourth section can have a larger outer diameter than the second section, the width of the two sections being the same. The fourth section can have an elevation so that the fourth section forms an abutment for the crimping, on which the crimp barrel rests. The fourth section can have the same outer diameter as the second section.

In a further preferred embodiment, a fifth section is arranged immediately proximal to the fourth section, the fifth section having a larger outer diameter than the fourth section. This has the advantage that the crimp sleeve is also secured against axial slipping. The axial alignment takes place of the coupling piece by locking the projection into the recess.

The fifth section preferably has a taper which extends in the proximal direction. This facilitates the insertion and withdrawal of the medical device into the catheter and avoids getting caught.

In a preferred embodiment, at least one first crimp sleeve is provided, which is arranged distally to the projection and encompasses at least a partial area of the first section and essentially the entire area of the third section. The first crimp barrel fulfills a double function. On the one hand, it represents the securing or distal support for the form-fitting connection. On the other hand, the first crimp sleeve also enables a wire element to be fixed at the distal end of the lattice structure. The first crimp barrel also represents an X-ray visible marker element.

In a further preferred embodiment, at least one second crimp sleeve is provided which is arranged proximally to the projection and encompasses at least a partial area of the second section and essentially the entire area of the fourth section. The form-fitting connection is additionally supported in the proximal direction by the second crimp sleeve, so that an even stronger connection point is ensured. The second crimp barrel also represents a radiopaque marker element.

In a preferred embodiment, the first crimp barrel, the second crimp barrel, the engagement element and the coupling piece form a row arrangement in the assembled state, the row arrangement preferably being precisely compatible with a 0.017 "catheter with an inner lumen of 0.420 mm. The advantage of the row arrangement is that that the two crimp sleeves can be arranged flexibly. For example, the two crimp sleeves can be arranged axially one behind the other, in particular distal and / or proximal to the joint instead of directly at the joint itself. This in turn has the advantage that the joint can be made smaller and The lattice structure can thus be compressed to a relatively small cross-sectional diameter, so that the medical device can be delivered in relatively small delivery systems and is particularly compatible with a 0.017 "catheter with an inner lumen of 0.420 mm.

In a further preferred embodiment, the engagement element preferably has a greater width than the web extension. On the one hand, this defines the maximum width of the row arrangement, which is decisive for the ability to feed the medical device into smaller feeding systems, in particular into a 0.017 "catheter with an inner lumen of 0.420 mm In other words, the engaging element has a sufficient wall thickness to be able to transmit higher tensile, compressive, bending and torsional forces. The larger the recess or the projection formed due to the corresponding negative shape, the stronger The cross-section of the recess and the cross-section of the web extension are of the same size, so that the available installation space is optimally used.

The cross section of the engagement element is preferably trapezoidal, the wider side of the trapezoid being arranged on the inside of the engagement element. This has the advantage that the engagement element takes up less space and therefore just fits through the crimp sleeves without play.

In order to enable optimal use of the cross section and the freedom from play of the fit when torsion occurs, the engagement element in the region of the recess preferably has two parallel sides which extend in the axial direction of the engagement element.

In order to enable a wire element to be fixed to a proximal end of the lattice structure, in a preferred embodiment at least one X-ray visible wire element is provided, which is guided along at least one web. The wire element has a wire end which is passed through the first crimp barrel. The end of the wire is connected to the web extension by the first crimp sleeve. The first crimp barrel can connect both one wire end of the wire element to the lattice structure and two ends of the same wire element or two wire ends of different wire elements to the lattice structure. It is possible for a total of four wire ends to be fixed. The wire ends are guided both through the first crimp sleeve and through the second crimp sleeve and are arranged centrally in the engagement elements. The use of a crimp sleeve to fix the wire element to the lattice structure, preferably to a distal end section of the lattice structure, is particularly simple and inexpensive.

To avoid vascular injury during treatment, the wire ends are the first crimp barrel and the second crimp barrel adhesively bonded to the coupling piece. The bond can be provided as an atraumatic bond that has rounded edges and is therefore gentle on the tissue.

In general, the medical device designed according to the invention can form an implant, for example a stent, or a temporarily deployable instrument, such as the thrombectomy device described above.

Another secondary aspect of the invention relates to a method for producing a medical device described above, wherein a projection, in particular a transverse anchor, is produced by laser material processing, wire eroding or grinding on a distal coupling piece of a transport wire. Furthermore, a recess is produced in an engagement element of a web extension by a laser cutting process, the recess extending essentially in the axial direction of the engagement element. The recess can be produced using a 2-axis laser cutting process or a 4-axis laser cutting process. The engagement element is positively connected to the coupling piece, the projection engaging in at least one recess of the engagement element. At least one first crimp sleeve is arranged distal to the projection, which encompasses at least a partial area of the first section and essentially the entire area of the third section of the coupling piece and at least one second crimp sleeve proximal to the projection, the at least a partial area of the second section and essentially the encompasses the entire area of the fourth section of the coupling piece. A series arrangement is formed by the first crimp sleeve, the second crimp sleeve, the engagement element and the coupling piece in the assembled state, so that the medical device can be fed into relatively small feed systems.

The invention is described in more detail below using an exemplary embodiment with reference to the accompanying schematic figures.

• 1 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei ein distales Kopplungsstück eines Transportdrahtes dargestellt ist;
• 2 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei ein proximales Ende der Gitterstruktur dargestellt ist;
• 3 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei eine formschlüssige Verbindung zwischen proximalen Ende der Gitterstruktur und dem distalen Ende des Transportdrahtes dargestellt ist (Montagezwischenzustand);
• 4 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei eine erste Crimphülse distal und eine zweite Crimphülse proximal zur formschlüssigen Verbindung angeordnet ist (Montagezwischenzustand);
• 5 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die formschlüssige Verbindung durch Crimpen der beiden Crimphülsen gesichert ist (Montagezwischenzustand);
• 6 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die formschlüssige Verbindung eine Verklebung aufweist (finaler Montagezustand);
• 7 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die freien Drahtenden eines Drahtelements durch eine Crimphülse fixiert sind;
• 8 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die formschlüssige Verbindung nur durch eine erste distale Crimphülse gesichert ist;
• 9 die medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei der Querschnitt der Eingriffselemente dargestellt ist;
• 10 die medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die Gitterstruktur in einem flach ausgebreiteten Zustand dargestellt ist; und
• 11 die medizinische Vorrichtung gemäß 10 in einer Seitenansicht.

In these show

• 1 a medical device according to an embodiment of the invention, wherein a distal coupling piece of a transport wire is shown;
• 2 a medical device according to an embodiment of the invention, wherein a proximal end of the lattice structure is shown;
• 3rd a medical device according to an exemplary embodiment according to the invention, a positive connection between the proximal end of the lattice structure and the distal end of the transport wire being shown (intermediate assembly state);
• 4th a medical device according to an exemplary embodiment according to the invention, wherein a first crimp sleeve is arranged distally and a second crimp sleeve is arranged proximally for the form-fitting connection (intermediate assembly state);
• 5 a medical device according to an exemplary embodiment according to the invention, the positive connection being secured by crimping the two crimp sleeves (intermediate assembly state);
• 6th a medical device according to an exemplary embodiment according to the invention, wherein the form-fitting connection has an adhesive bond (final assembly state);
• 7th a medical device according to an embodiment of the invention, wherein the free wire ends of a wire element are fixed by a crimp sleeve;
• 8th a medical device according to an embodiment of the invention, wherein the positive connection is only secured by a first distal crimp sleeve;
• 9 the medical device according to an embodiment of the invention, wherein the cross section of the engagement elements is shown;
• 10 the medical device according to an embodiment of the invention, wherein the lattice structure is shown in a flat spread-out state; and
• 11 the medical device according to 10 in a side view.

In general, the medical device has a lattice structure that is formed from interconnected webs. The webs are coupled to one another at web connectors, the web connectors each being able to connect four webs to one another. The lattice structure is preferably designed to be rotationally symmetrical at least in sections.

At this point, it should be noted that the lattice structure is tubular. The tubular shape results from the fact that the lattice structure is cut from a tube material, in particular laser-cut. Other geometries of the lattice structure are possible. Next to the Laser cutting, other manufacturing processes are possible.

The exemplary embodiments according to the invention described in more detail below each show medical devices which are suitable for intravascular use. Other types of intravascular medical devices are also conceivable.

1 shows the distal end of a transport wire 15th , on which there is a coupling piece 14th is located. The coupling piece 14th has the function of being the proximal end of the lattice structure 10 firmly to the transport wire 15th connect to. The connection is made in a form-fitting manner. The form fit ensures a sufficiently strong connection that can absorb or transmit any tensile, compressive, bending and torsional forces that occur. So can the lattice structure 10 released from the catheter for treatment and withdrawn after the thrombectomy.

In order to enable the positive connection, the coupling piece 14th two protrusions 16 on, which is essentially transverse to the longitudinal axis of the transport wire 15th extend. The protrusions 16 are used as cross anchors 18th , in particular designed as a T-anchor, so that a symmetrical introduction of force is possible. In other words, the protrusions extend 16 radially outwards. The protrusions 16 can have almost any laterally or radially pronounced shape. For example, the projections 16 have a round, zigzag-shaped or polygonal outer contour, which extends in the circumferential direction and / or longitudinal direction of the coupling piece 14th extends.

On the one hand are the protrusions 16 designed in such a way that they can just about be fed through the inner diameter of a crimp barrel. On the other hand, they have a sufficient material cross-section to be able to transmit the tensile, compressive, bending and torsional forces that occur.

It is conceivable that the coupling piece 14th several evenly over the circumference of the coupling piece 14th distributed projections 16 includes. So can the coupling piece 14th for example three protrusions 16 include, in the circumferential direction of the coupling piece 14th are arranged and each have an angle of 120 ° to each other. There can be four protrusions 16 be provided in the circumferential direction of the coupling piece 14th are arranged and each have an angle of 90 ° to each other. In other words, the coupling piece 14th so many ledges 16 as possible in the circumferential direction and / or longitudinal direction of the coupling piece 14th have to enable a stronger form-fitting connection. Basically, however, a head start is sufficient 16 to ensure a sufficiently strong form-fitting connection.

The coupling piece 14th is essentially cylindrical and is produced by laser material processing, wire EDM or grinding, so that the coupling piece 14th at least a head start 16 Has included section.

Specifically, the coupling piece includes 14th several axially adjacent sections B1 to B5 , each having a different outer diameter, wherein the projection 16 has the maximum outside diameter. The first paragraph B1 of the coupling piece 14th is immediately distal to the protrusion 16 arranged. The second section B2 is immediately proximal to the protrusion 16 arranged. The second section B2 has a larger outer diameter than the first section B1 in order to offer possible wire ends of a wire element, in particular a DFT wire element, more space in the case of a distal crimping. However, this is not absolutely necessary. The first paragraph B1 and the second section B2 can also have the same outside diameter

The third section B3 is immediately distal to the first section B1 arranged, the third section B3 a larger outside diameter than the first section B1 having. Where is the width of the third section B3 and the first section B1 equal. The third section B3 has an elevation to form an abutment for the crimping.

The fourth section B4 is immediately proximal to the second section B2 arranged, the fourth section B4 a larger outside diameter than the second section B2 having. Where is the width of the fourth section B4 and the second section B2 equal. The fourth section B4 has an elevation to form an abutment for the crimping.

The fifth section B5 is immediately proximal to the fourth section B4 arranged, the fifth section B5 a larger outside diameter than the fourth section B4 having. This also secures the crimp sleeve against slipping axially. The fifth section B5 also has a taper 19th which extends in the proximal direction.

2 shows the medical device according to an exemplary embodiment according to the invention, a proximal end of the lattice structure being shown.

Specifically, the lattice structure 10 several bar processes 11 , especially two web processes 11 which is the outermost region of the lattice structure in the proximal direction 10 form.

The bar processes 11 are pin-like and extend from an end connector 11 ' parallel to the longitudinal axis of the lattice structure 10 . The end connector 11 ' connects two bridges 28 with each other at the proximal end portion 10b the lattice structure 10 are arranged.

One bar process each 11 each includes an engagement element 12th that is a recess 17th having. The recesses have 17th essentially the same shapes as the protrusions 16 on. Thus, one projection at a time 16 in one recess each 17th intervene so that a positive connection is created that is strong enough to transmit the tensile, compressive, bending and torsional forces that occur.

The recesses 17th have a closed shape. The recesses 17th extend essentially in the axial direction of the engagement elements 12th . The recesses 17th correspond to the contour of the engagement elements 12th . It is possible that the recesses 17th have a curved, in particular round, zigzag-shaped or polygonal shape. It is provided that the recesses 17th each comprise at least two opposite sides. Specifically, the recesses point 17th each have a rectangular closed shape, which is based in the axial direction on the engagement element 12th extend.

The recesses 17th are made by a laser cutting process. The recesses 17th can be produced using a conventional 2-axis laser cutting process or 4-axis laser cutting process. In this way, the two sides of the recesses running in the axial direction can in each case 17th are cut exactly parallel to each other instead of conical, so that the recesses 17th the corresponding negative shapes of the projections 16 form. This enables the protrusions 16 precisely fitting into the recesses 17th can be arranged.

When making the recesses 17th Using a conventional 2-axis laser cutting process, around 70% of the forces that occur can be transferred.

A first crimp sleeve is used to support and secure the positive connection 20th provided that the web processes 11 encompasses and distal to the engagement elements 12th is arranged. On the first crimp barrel 20th is discussed in more detail below.

3rd shows an intermediate assembly step in which the positive connection 13th between the engagement elements 12th and the coupling piece 14th is shown.

The form-fitting connection 13th enables a sufficiently strong connection to be able to transmit the tensile, compressive, bending and torsional forces that occur. Since this is a detachable connection, it is also secured. The form-fitting connection could be achieved without additional securing 13th solve because the web processes 11 have free ends.

About the spreading of the bar extensions 11 to prevent or the positive connection 13th at least one first crimp barrel is to be secured 20th intended.

The first crimp barrel 20th first via the form-fitting connection 13th pushed on and arranged as far as possible in the distal direction, so that the bar processes 11 sufficiently spread and the projections 16 thereby precisely fitting into the recesses 17th can be arranged.

After that, the engaging element 12th and the coupling element 14th positioned relative to one another in order to connect them to one another in a form-fitting manner. The form-fitting connection 13th is created by the protrusions 16 into the recesses 17th intervention. The projections preferably engage 16 precisely fitting into the recesses 17th a. The axial alignment is achieved by the locking of the protrusions 16 into the recesses 17th reached.

Due to the form-fitting connection 13th Forces, in particular tensile and compressive forces in the axial direction related to the coupling piece, as well as bending and torsional forces can be transmitted that occur during treatment, especially when the medical device is to be withdrawn into a delivery system, for example a catheter, after a positioning attempt .

Then a second crimp barrel 21 via the coupling piece 14th pushed on, the coupling piece 14th a rejuvenation 19th has to slide on the second crimp barrel 21 to facilitate.

The crimp sleeves 20th , 21 can preferably be X-ray visible or comprise an X-ray visible material. The crimp sleeves 20th , 21 can even represent radiopaque marker elements. This enables the proximal end of the lattice structure 10 is particularly clearly visible under an X-ray control. In this way, the Positioning the lattice structure 10 for example, relieved in a blood vessel.

4th shows the intermediate assembly step, in which a first crimp sleeve is arranged distally and a second crimp sleeve is arranged proximally for the form-fitting connection.

The first crimp barrel 20th , the second crimp barrel 21 and the engaging elements 12th are arranged axially one behind the other so that they are together with the coupling piece 14th an array R. form. This engages around the first crimp barrel 20th a distal area of the bar processes 11 and at least a portion of the first section B1 and essentially the entire area of the third section B3 of the coupling element 14th so that the first crimp barrel 20th a distal securing of the form-fitting connection 13th represents. The second crimp barrel 21 encompasses a proximal area of the bar extensions 11 and at least a portion of the second section B2 and substantially the entire area of the fourth section B4 of the coupling element 14th so that the second crimp barrel 21 a proximal securing of the form-fitting connection 13th represents. In other words, the first crimp barrel 20th the task of the positive connection 13th distal and the second crimp barrel 21 the task of the positive connection 13th secure proximally. The third section B3 and the fourth section B4 of the coupling element 14th have an elevation to form an abutment for the crimping.

5 . shows the intermediate assembly state in which the positive connection is secured by crimping the two crimp sleeves.

In comparison to the direct encompassing of the joint with a single crimp sleeve or the fixing of the positive connection by arranging a crimp sleeve and the joint on top of one another, the row arrangement has the advantage that the crimp sleeves can be arranged axially one behind the other. The fixation of the form-fit connection takes place flexibly, in particular distal and / or proximal to the form-fit connection. Specifically, the first crimp barrel is fixed 20th the positive connection 13th distal and the second crimp barrel 21 the positive connection 13th proximal. This shows the form-fitting connection 13th as well as the two crimp sleeves 20th , 21 about the same, especially a small outer diameter. As a result, less space is taken up and the lattice structure 10 can thus be compressed to a relatively small cross-sectional diameter, so that the medical device can be delivered in relatively small delivery systems and, in particular, is compatible with a 0.017 "catheter with an inner lumen of 0.420 mm.

6th . shows the final assembly state of the form-fitting connection, which is an adhesive bond K having. The bonding K is designed as an atraumatic bond, ie the bond K has rounded edges and is therefore gentle on the tissue. In this way, vascular injuries can be avoided during the treatment. Furthermore, the bonding K the insertion and withdrawal into the catheter is facilitated, since the interlocking connection can slide better and a sticking is avoided.

7th shows an assembly state of the form-fitting connection in which the free wire ends 23 of a wire element 24 through the first crimp barrel 20th are passed through. Here are the free ends of the wire 23 guided through a space between the first crimp barrel 20th , the third section B3 and the web processes 11 the lattice structure 10 is trained.

The wire element or elements 24 are made of a radiopaque material. For example, it can be a solid material made of an X-ray visible material. It is also possible to use a composite material, for example so-called DFT wire elements. Such wire elements have a core wire made of an X-ray visible material, for example platinum, tantalum or gold, and a sheath made of a shape memory material.

An example of a DFT wire element has a platinum core with a diameter of 45-55 µm and a nitinol jacket, the outer diameter of which corresponds to the core diameter plus approx. 20 µm. Other materials and varied dimensions or just an X-ray visible wire without a super-elastic jacket would also be conceivable.

In general, all radiopaque materials customary for implants can be used.

The first crimp barrel 20th fulfills a double function here. On the one hand, it provides a distal safeguard for the form-fitting connection 13th for sure. On the other hand, it enables the additional fixing of the wire element 24 at a proximal end of the lattice structure 10 . The first crimp barrel 20th not just the free wire ends 23 a single wire element 24 with each other on the lattice structure 10 fix, but also wire ends 23 various wire elements 24 .

It is possible to have a total of four wire ends 23 be fixed. Thereby the wire ends 23 both through the first crimp barrel 20th as well as through the second crimp barrel 21 out and are centered in the engagement elements 12th arranged.

8th shows the medical device according to an exemplary embodiment according to the invention, the form-fitting connection being secured by only one crimp sleeve which is arranged distal to the form-fitting connection.

In contrast to the previously described crimp sleeves 20th , 21 is the in 8th shown crimp barrel 20 ' formed wider or longer in the axial direction. The use of such a wide crimp barrel 20 ' has the advantage of having an additional second crimp barrel 21 can be dispensed with, which would be necessary for the positive connection 13th secure proximally.

9 shows the medical device according to an exemplary embodiment according to the invention, the cross section of the engagement elements being shown.

The engaging elements 12th have a greater width than the web processes 11 on. On the one hand, this defines the maximum width of the joint. On the other hand, this results in a larger formation of the recesses 17th possible because of the recesses 17th there is enough material around. The engaging elements 12th thus have a sufficient wall thickness to be able to transmit the tensile, compressive, bending and torsional forces that occur.

The two webs above and below the recesses 17th together optimally have the same cross section as the recesses 17th on. The recesses 17th optimally have the same cross-section as the bar extensions 11 on. The optimal ratio between the cross-section of the recesses 17th and the cross-section of the web extensions 11 is 2: 1.

Around the first crimp barrel 20th just about the engagement elements 12th to be able to postpone are the cross-sections of the engagement elements 12th trapezoidal. Here are the wider sides 22nd the Trapeze T on the inside of the engagement elements 12th arranged. This can be done well in 9 detect.

The trapezoids T are produced by an "off-center cutting process" and have in the area of the recesses 17th two parallel sides S1 and S2 on, which are important for freedom from play when torsional forces occur. The parallel sides S1 , S2 extend over the entire axial lengths of the recesses 17th . The "off-center cutting process" results in a material cross-section gain of approx. 30% compared to the pure radial cutting process.

10 shows the medical device according to an embodiment of the invention, wherein the lattice structure 10 is shown in a flat spread state. The lattice structure 10 is specifically designed as a stent component that is suitable for rapid recanalization, the proximal end of the stent component with a distal coupling piece 14th a transport wire, not shown 15th through a like in 6th and 7th shown positive connection 13th connected is.

The lattice structure 10 or stent component has a hybrid cell design, ie the lattice structure 10 includes, on the one hand, closed cells 25th which cause excellent apposition to the vascular wall and allow safe uptake of thrombi, and on the other hand larger cells 26th . The larger cells 26th may in some embodiments have anchoring elements that enable an effective retention of the thrombi and a safe, atraumatic removal. Such anchoring elements can be made by two additional webs of the lattice structure 10 be formed, which are connected in a V-shape to a point that leads into the larger cell 26th protrudes.

Basically the cells are 25th , 26th the lattice structure 10 each of several, integrally connected webs 28 educated. The bridges 28 are on bar connectors 29 coupled together, the web connector 29 four webs each 28 connect with each other. The ones to the larger cells 26th adjacent bar connector 29 however, only connect three bars 28 together.

For reasons of presentation, the 10 reverted to an unfolded view in which the lattice structure 10 is shown cut in the longitudinal direction and spread flat. It goes without saying that the lattice structure 10 is actually tubular or at least partially tubular. This is according to the side view 11 recognizable. The tubular shape results from the lattice structure 10 cut from a pipe material, in particular laser cut.

The lattice structure 10 has several pin-like formed web extensions 11 which is the outermost region in the proximal direction, in particular the proximal end section 10b , the lattice structure 10 form. In 10 are specifically two web processes 11 shown, each with a web extension 11 an engagement element 12th has, so that a form-fitting connection described above 13th with a distal coupling piece 14th a transport wire 15th is possible. The engagement element 12th includes a rectangular recess 17th that form fit with a ledge 16 of the coupling piece 14th cooperates.

The form-fitting connection 13th between the lattice structure 10 the stent component and the transport wire 15th is specifically made possible by the fact that the in 1 illustrated projection 16 of the coupling piece 14th in the in 2 shown, preferably rectangular, recess 17th of the engagement element 12th engages so that a sufficiently strong connection between the stent component and the transport wire 15th is created.

The medical device according to 10 includes two wire elements 24 , 24 ' so that a total of four wire ends 23 , 23 ' through the in 10 first crimp barrel, not shown 20th be fixed. The first crimp barrel 20th corresponds to the first crimp barrel 20th like them in the 6th and 7th is shown.

It is possible that the wire ends 23 , 23 ' or both through the first crimp barrel 20th as well as through the second crimp barrel 21 guided and centered in the engagement elements 12th are arranged and fixed. It is possible for more than two wire elements 24 , 24 ' are provided, for example a total of three or four wire elements 24 , 24 ' , which are arranged in a pattern distributed on the circumference.

The wire elements are used for fastening 24 , 24 ' in areas in the lattice structure 10 braided and / or wrapped around individual webs 28 the lattice structure 10 . Several wire elements can be used independently of each other with the lattice structure 10 be intertwined and / or the individual webs 28 the lattice structure 10 wrap around.

The wire elements 24 , 24 ' run essentially parallel or laterally along the webs 28 . Generally, the wire elements extend 24 , 24 ' preferably along a row of webs 30th , by several webs arranged one behind the other 28 is formed. The row of bridges 30th runs preferably helically around the longitudinal axis of the lattice structure 10 .

In addition, the wire elements 24 , 24 ' around the jetties 28 the row of bridges 30th be wrapped. The wire elements 24 , 24 ' achieve a full turn, in particular a turn by 360 °, after a web 28 or according to a web length, the length of a web 28 the one along the footbridge 28 Distance to be determined between two crossing points of webs 28 corresponds to.

The wire elements 24 , 24 ' form loops 31 , 31 ' in the area of the distal end section 10a the lattice structure 10 are arranged. The distal end section 10a forms the axial end of the tubular lattice structure 10 which emerges first when the device is discharged from a catheter.

In the area of the loops 31 , 31 ' change the wire elements 24 , 24 ' their direction in such a way that the wire elements 24 , 24 ' from the lattice structure 10 be led out and in again. The loops 31 , 31 ' each have a first leg and a second leg which extend at an angle to one another.

11 FIG. 10 shows the medical device according to FIG 10 again in a side view. It can be clearly seen that the stent component or lattice structure 10 with the transport wire 15th via the coupling piece 14th of the transport wire 15th and the engaging element 12th the lattice structure 10 firmly, in particular with the formation of the form-fit connection 13th , connected is. The total of four wire ends 23 , 23 ' , of which only two can be seen in the side view, are with the first crimp barrel 20th on the coupling piece 14th and / or at the web extensions 11 fixed.

At a distal end portion 10a the lattice structure 10 are X-ray marker sleeves 27 intended. To do this go from the end connectors 11 ' the lattice structure 10 at the distal end portion 10a each made of web pins that are parallel to the longitudinal direction of the lattice structure 10 extend. The x-ray marker sleeves are on the bar pins 27 crimped on. The X-ray marker sleeves 27 can have an X-ray visible material, in particular gold, tantalum, platinum or alloys thereof.

Also the crimp sleeves 20th , 21 can have an X-ray visible material, for example gold, tantalum, platinum or alloys thereof. In this respect, the crimp sleeves 20th , 21 at the proximal end section 10b the lattice structure 10 or at the distal end of the transport wire 15th just like the X-ray marker sleeves 27 at the distal end portion 10a the lattice structure 10 fulfill an X-ray visibility function.

List of reference symbols

10

Lattice structure

10a

distal end section

10b

proximal end section

11

Bar process

11 '

End connector

12th

Engagement element

13th

positive-locking connection

14th

Coupling piece

15th

Transport wire

16

head Start

17th

Recess

18th

Cross anchor

19th

rejuvenation

20th

first crimp barrel

20 '

wide crimp barrel

21

second crimp barrel

22nd

wider side

23

Wire end

23 '

Wire end

24

Wire element

24 '

Wire element

25th

cell

26th

cell

27

X-ray marker sleeve

28

web

29

Bar connector

30th

Row of bars

31

loop

31 '

loop

B1

first section

B2

second part

B3

third section

B4

fourth section

B5

fifth section

K

Bonding

R.

Row arrangement

S1

first parallel side

S2

second parallel side

T

Trapezoid

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102018107594 A1 [0001, 0002, 0005]

Claims (26)

Medical device for intravascular treatment with an at least partially tubular lattice structure (10) made of integrally interconnected webs (28), the lattice structure (10) having a web extension (11) comprising an engagement element (12) at a proximal end section (10b) , wherein the engagement element (12) is connected by a form-fitting connection (13) to a distal coupling piece (14) of a transport wire (15), characterized in that the coupling piece (14) has at least one projection (16) and the engagement element (12) have at least one recess (17), the projection (16) engaging in the recess (17) of the engagement element (12). Medical device according to Claim 1 characterized in that the recess (17) is designed to be closed, the recess extending essentially in the axial direction of the engagement element (12). Medical device according to Claim 1 or 2 characterized in that the recess (17) essentially corresponds to the contour of the engagement element (12). Medical device according to one of the preceding claims, characterized in that the coupling piece (14) has at least two projections (16) which are designed as transverse anchors (18). Medical device according to one of the preceding claims, characterized in that the transverse anchor (18) is designed as a T-anchor. Medical device according to one of the preceding claims, characterized in that the projection (16) corresponds to the shape of the recess (17). Medical device according to Claim 6 characterized in that the projection (16) extends essentially in the axial direction of the coupling piece (14). Medical device according to one of the preceding claims, characterized in that the coupling piece (14) comprises a plurality of axially adjacent sections (B1-B5) which each have different external diameters, the projection (16) having the maximum external diameter. Medical device according to Claim 8 characterized in that a first section (B1) is arranged immediately distal and a second section (B2) is arranged immediately proximal to the projection (16). Medical device according to Claim 9 characterized in that a third section (B3) is arranged immediately distal to the first section (B1). Medical device according to Claim 9 or 10 characterized in that a fourth section (B4) is arranged immediately proximal to the second section (B2). Medical device according to Claim 11 characterized in that a fifth section (B5) is arranged immediately proximal to the fourth section (B4), the fifth section (B5) having a larger outer diameter than the fourth section (B4). Medical device according to Claim 12 characterized in that the fifth section (B5) has a taper (19) which extends in the proximal direction. Medical device according to one of the Claims 9 - 13th characterized in that at least one first crimp sleeve (20) is provided, which is arranged distally to the projection (16) and encompasses at least a partial area of the first section (B1) and essentially the entire area of the third section (B3). Medical device according to one of the Claims 10 - 14th characterized in that at least one second crimp sleeve (21) is provided, which is arranged proximal to the projection (16) and encompasses at least a partial area of the second section (B2) and essentially the entire area of the fourth section (B4). Medical device according to one of the preceding claims, characterized in that the first crimp sleeve (20), the second crimp sleeve (21), the engagement element (12) and the coupling piece (14) form a series arrangement (R) in the assembled state. Medical device according to Claim 16 characterized in that the row arrangement (R) is precisely compatible with a 0.017 "catheter with an inner lumen of 0.420 mm. Medical device according to one of the preceding claims, characterized in that the engagement element (12) has a greater width than the web extension (11). Medical device according to Claim 18 characterized in that the cross section of the Engagement element (12) is trapezoidal, wherein the wider side (22) of the trapezoid (T) is arranged on the inside of the engagement element (12). Medical device according to Claim 19 characterized in that the engagement element (12) in the region of the recess (17) has two parallel sides (S1, S2) which extend in the axial direction of the engagement element (12). Medical device according to one of the Claims 14 - 20th characterized in that at least one X-ray visible wire element (24) is provided which is guided along at least one web, the wire element (24) having a wire end (23) which is passed through the first crimp sleeve (20). Medical device according to one of the preceding claims, characterized in that the wire end (23), the first crimp sleeve (21) and the second crimp sleeve (22) are adhesively connected to the coupling piece (14). Medical device according to one of the preceding claims, characterized in that the device is a thrombectomy device. A method of manufacturing a medical device according to any one of the preceding claims, wherein - A projection (16), in particular a transverse anchor (18), is produced by laser material processing, wire eroding or grinding on a distal coupling piece (14) of a transport wire (15); - A recess (17) is produced in an engagement element (12) of a web extension (11) by a laser cutting process, the recess (17) extending essentially in the axial direction of the engagement element (12); - The engagement element (12) is positively connected to the coupling piece (14), the projection (16) engaging in at least one recess (17) of the engagement element (12); - At least one first crimp sleeve (20) is arranged distally to the projection (16), which surrounds at least a partial area of the first section (B1) and essentially the entire area of the third section (B3). Procedure according to Claim 24 , characterized in that at least one second crimp sleeve (21) is arranged proximal to the projection (16), which surrounds at least a partial area of the second section (B2) and essentially the entire area of the fourth section (B4). Procedure according to Claim 24 or 25th , characterized in that the first crimp sleeve (20), the second crimp sleeve (21), the engagement element (12) and the coupling piece (14) in the assembled state form a series arrangement (R) which is connected to a 0.017 "catheter is perfectly compatible with an inner lumen of 0.420 mm.

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