DE102011121963A1 - Catheter used during endovascular intervention of blood vessel, has deformable distal portion that is provided with distal opening, and inner and outer pipe elements which are axially displaced with respect to each other - Google Patents

Abstract

The catheter (1) has a lumen that is extended from distal end to proximal end of inner pipe element (3). The outer pipe element (2) and inner pipe element are arranged coaxially with respect to each other. The distal opening is provided in deformable distal portion (6) which is extended from primary plane to secondary plane. The distal ends of the outer and inner pipe elements are connected. The inner and outer pipe elements are axially displaced with respect to each other.

Description

The invention relates to a catheter with a variable tip opening for diagnostic and therapeutic purposes, primarily for use in vascular systems, preferably for closing aneurysms, as used for example in endovascular interventions.

For the treatment of vascular diseases or treatments of diseases in the vicinity of blood vessels, catheters are advanced via the vascular system to the site of the disease. These vascular diseases can z. As Gefäßaussackungen, so-called aneurysms. Other vascular diseases are z. As thrombi or blood clots that can lead to blockages of the blood supply. Thrombi are either dissolved medically or mechanically removed.

The mechanical removal of thrombi takes place with corkscrew-type brushes or basket-shaped wires. This captures the thrombus. Then the thrombus is withdrawn into the catheter. In this case, a wide opening of the catheter tip is desirable to safely aspirate the thrombus.

Thrombi are difficult to remove mechanically, especially with small vessels and the microcatheters used, as the catheter opening is often too small to pull the thrombus into the catheter.

Aneurysms are treated differently depending on species, location and size. It can be surgically removed or stapled externally. This can cause significant trauma. For example, an endovascular procedure is known in which aneurysms are filled with so-called coils or adhesives. The extent of the aneurysm is only slightly reduced.

In aneurysm therapy, filling does not lead to a reduction in the volume of the vessel lining. The pressure on intact structures and the associated restrictions on the existing Gefäßaussackungen remain intact. Furthermore, no healthy vessel surfaces are brought together, which hampers healing.

Against this background, the object of the present invention is to provide a catheter in order to enable a simple localized treatment of Gefäßaussackungen with a volume reduction of these.

This object is achieved by a catheter according to claim 1 and the further advantageous embodiments according to the subclaims.

• – ein Außenrohrelement, welches ein erstes distales Ende und ein erstes proximales Ende aufweist,
• – ein Innenrohrelement, welches ein zweites distales Ende und ein zweites proximales Ende und ein sich vom zweiten distalen Ende zum zweiten proximalen Ende erstreckendes Lumen aufweist, wobei
• – das Außenrohrelement und das Innenrohrelement koaxial zueinander angeordnet sind und einen Zwischenraum, einen distalen Bereich mit einer distalen Öffnung, einen Zwischenbereich und einen proximalen Bereich bilden, wobei sich der distale Bereich von einer ersten Ebene zu einer zweiten Ebene erstreckt.

According to the invention, a catheter is proposed, which is suitable for diagnostic and therapeutic purposes, mainly for use in vascular systems. This includes at least

• An outer tube member having a first distal end and a first proximal end,
• An inner tube member having a second distal end and a second proximal end and a lumen extending from the second distal end to the second proximal end, wherein
• - The outer tube member and the inner tube member are arranged coaxially with each other and form a gap, a distal region with a distal opening, an intermediate region and a proximal region, wherein the distal region extends from a first plane to a second plane.

The outer tube member and the inner tube member communicate at least in a discrete region of the first and second distal ends, wherein the inner tube member and the outer tube member are axially displaceable relative to each other and wherein the distal portion is deformable.

The proximal end of the catheter is suitable, for example, for receiving a connector, preferably a Luer connector. The distal region, which may be formed as a catheter tip, is bounded by the first and second planes.

By an axial displacement of the inner tube member to the outer tube member and an associated targeted application of force to the catheter tip this can be deformed, in particular bent and thereby also controlled. Here, the first and the second level are to be regarded as fictitious levels.

An embodiment of the invention provides that the distal region can be expanded by axial displacement of the inner tube element to the outer tube element. In a further embodiment, the distal region can be narrowed by axial displacement of the inner tube element towards the outer tube element.

Due to the deformable, in particular expandable or constricting tip larger thrombi can be pulled into the lumen. Also, smaller aneurysms can be aspirated into the lumen, these by narrowing the distal opening like a sack can be closed.

The catheter is used in particular in the diagnostic and therapeutic field, for example in endovascular interventions and can be used primarily for use in vascular systems but also in the vicinity of vessels. Due to the coaxial structure, the catheter diameter can be kept small and yet a large opening of the distal end can be achieved. This opens up new treatment options for the treatment of aneurysms and thrombi.

In a wide embodiment of the invention, it is provided that the distal region can be flattened by axial displacement of the inner tube element towards the outer tube element. In this way, the catheter tip can for example be applied sealingly to a vessel, whereby preferably the aspiration of an aneurysm is facilitated.

According to a particularly preferred embodiment of the invention it is provided that the catheter has a reinforcing layer, which is arranged in the intermediate space and in communication with the inner tube element, preferably at discrete locations, whereby the catheter is stiffened in the intermediate region and in addition a stiffening of the inner tube element occurs , As a result, the catheter tip can be easily opened and closed and thus used as a gripping element for detecting, for example, trunks or aneurysms.

A further embodiment of the invention provides that a reinforcing layer is provided, which is arranged in the intermediate space and is in communication with the outer tubular element, preferably at discrete locations, whereby the catheter is stiffened in the intermediate region and in addition a stiffening of the outer tubular element occurs. By this arrangement, it is possible to open and close the catheter tip defined while improving the function of gripping.

In addition, the reinforcing layer can also be in communication with the inner tube element and at least partially with the outer tube element such that an axial displacement of the inner tube element relative to the outer tube element is still possible in order to deform at least the catheter tip or the distal region of the catheter.

There is also the possibility that the reinforcing layer is in communication with the outer tube element and at least partially with the inner tube element such that an axial displacement of the inner tube element relative to the outer tube element is still possible in order to deform at least the catheter tip or the distal region of the catheter.

The outer tube element and / or the inner tube element and / or the reinforcing layer are formed in a further embodiment of the invention in one or more layers. Here, one or more fabrics, knitted fabrics, braids, meshes, nets, nonwovens, fiber strand formations can be used. Also may be provided a spring, a continuous or perforated foil or a continuous or perforated tube and the like, as well as combinations thereof.

In particular, by material combinations in which a stiffer and a more flexible material are related to each other, excellent properties for the catheter in particular in the distal region and in this case in particular with regard to its specific deformability, such as bendability, steerability, openability and lockability can be produced, with unwanted Injuries in the area of vessel walls can be avoided.

• – Kunststoffe, vorzugsweise TPU, Silikon, Kautschuk, PE, PP, PA, bevorzugt Nylon oder Darcon, Biopolymere, sowie deren Mischungen und Copolymere und Kombinationen daraus, vorzugsweise Füllstoffe beinhaltend, besonders bevorzugt Calciumcarbonat oder anorganische Faserstoffe,
• – Metall, beispielsweise Titan, Edelstahl, vorzugsweise körperverträgliche Metalllegierungen,
• – keramische Materialien,
• – natürliche Faserstoffe, vorzugsweise Hanf oder Baumwolle.

In a further embodiment of the invention it is provided that the outer tube element and / or the inner tube element and / or the reinforcing layer comprise at least one material which belongs to the following group:

• Plastics, preferably TPU, silicone, rubber, PE, PP, PA, preferably nylon or darcon, biopolymers, and mixtures thereof and copolymers and combinations thereof, preferably containing fillers, particularly preferably calcium carbonate or inorganic fibrous materials,
• Metal, for example titanium, stainless steel, preferably biocompatible metal alloys,
• - ceramic materials,
• - natural fibers, preferably hemp or cotton.

By such a wide-ranging possibility of material combination of the catheter can be adjusted in defined sub-areas functionally to the particular application.

It has proved to be advantageous if at least the outer tube element comprises a different material than the inner tube element. As a result, catheters with variable properties can be produced.

For example, a combination of a very flexible outer tube member with a stiffer inner tube member when placing the catheter on a vessel wall and possibly applying a negative pressure to a tremendous flattening of the catheter tip, while maintaining the diameter of the distal opening, but also can experience an enlargement or narrowing and the catheter tip can be fixed positively on the vessel wall to realize subsequent movements that lead to a constriction or dilation of the catheter tip to realize.

According to a further embodiment of the invention it is provided that the reinforcement layer extends in the intermediate space partially over the distal region of the catheter. In conventional catheters, it is known that the reinforcing layer extends over the entire distal region. According to the invention, a partial extension of the reinforcing layer into the distal region leads to a defined deformation of the distal region being made possible. For example, the reinforcing layer may leak at an angle in the distal region between the second and first plane.

In a particularly preferred embodiment of the invention, the distal region can be bent on one or more sides by axial displacement of the inner tube element towards the outer tube element.

It is also envisaged that the reinforcing layer extends in the intermediate space and adjoins the second plane of the distal region and thereby stands in connection with the inner tube element or the outer tube element at least in a discrete area.

The reinforcing layer may be in discrete locations as well as over the entire surface with the inner tube member or the outer tube member in conjunction. It is also contemplated that the reinforcing layer is disposed within the inner tube member or the outer tube member. These arrangements of the reinforcing layer can ensure in the respective tubular element that a more effective transmission of force can take place with relative movement of the tubular elements relative to one another.

The aforementioned arrangements may also be provided alternately in sections in the catheter according to the invention in order, for example, to produce in sections a better steerability or mobility of the catheter.

Due to its construction, the catheter according to the invention can have very different dimensions. For example, for the inner tube element and / or the outer tube element and / or the reinforcing layer outer diameter between 0.2 mm to 20 mm, preferably between 0.4 mm to 10 mm, more preferably between 0.4 mm to 3 mm. The wall thickness ranges can be provided between 0.001 mm to 2 mm.

For applications in the area of an aorta or large vein, catheters with an outer diameter of up to 8 mm can be used. For very small vessels, microcatheters with outer diameters of about 0.4 mm may be provided.

The entire catheter or the inner tube element and / or the outer tube element and / or the reinforcing layer can be produced for example by extrusion, coextrusion or injection molding.

It is further contemplated that the inner tube member with the outer tube member and / or the reinforcing layer with the inner tube member and / or the outer tube member during the manufacturing process, such as extrusion, coextrusion or injection molding or a subsequent joining process, for example by gluing, welding, lasers and the like in combination to be brought.

By way of example, embodiments of the invention are illustrated in the following figures and described in more detail.

Show it:

1a : the schematic structure of a catheter in the initial state,

1b FIG. 2 schematically shows the structure of a catheter in the expanded state, FIG.

1c FIG. 2 schematically shows the structure of a catheter in the narrowed state, FIG.

2a : schematically the detailed structure of the catheter after 1a .

2 B : schematically the detailed structure of the catheter after 1b .

2c : schematically the detailed structure of the catheter after 1a but flattened,

3a : The schematic structure of a catheter with expiring reinforcing layer and

3b : schematically the catheter 3a in the bent state.

The illustrated figures show the applicability of the catheter by way of example only, and are not limited thereto.

In 1a becomes schematically a catheter 1 shown in the initial state. The catheter includes three coaxially arranged pipe elements, ie an outer pipe element 2 , an inner tube element 3 and an intermediate reinforcing layer 9 , which is also designed as a tubular element. The reinforcement layer 9 can also be in the inner tube element 3 or the outer tube element 2 be integrated (in 1a not shown). The catheter tip passes through the distal area 6 formed, represented in the detail "A". At the proximal area 8th there is a connection, z. For example, a luer connector 12 , This connector 12 includes at least one outer piece 12a that with the outer tube element 2 of the catheter 1 is connected and an inner piece 12b that with the inner tube element 3 of the catheter 1 connected is.

In 1b becomes schematically a catheter 1 shown in the expanded state. In this case, the inner tube element 3 by means of the inner piece 12b the luer connector 12 in the direction of the distal area 6 of the catheter 1 been postponed, which by an arrow F for the introduction of force in the area of the connector 12 is shown, resulting in the tip or the distal region 6 of the catheter 1 that is between the imaginary and fictive levels 6b and 6a extends, has expanded, as can be seen in the detail "B".

In 1c becomes schematically a catheter 1 shown in the constricted state. In this case, the inner tube element 3 by means of the inner piece 12b the luer connector 12 towards the proximal region 8th of the catheter 1 has been postponed, which is indicated by the arrow F for the introduction of force in the area of the connector 12 is shown, resulting in the tip or the distal region 6 of the catheter 1 that is between the imaginary levels 6b and 6a extends, has narrowed, as can be seen in the detail "C".

In 2a will schematically show the detailed structure of the catheter 1 to 1a in the initial state shown as a top view and in sectional view AA. In the area of the proximal ends 2 '' and 3 '' is the connector for a connector 12 (in the 2a not shown). The inner tube element 3 and the outer tube member 2 are at their distal ends 2 ' and 3 in the area of the first level 6a connected with each other. This results between the inner tube element 3 and the outer tube member 2 a cavity 6c , The inner tube element 3 and the outer tube member 2 consist in this section of a very flexible material. The reinforcement layer 9 ends below the first level 6b , The catheter tip will pass through the first 6a and the second level 6b limited.

Will the inner pipe element 3 by operation of the inner piece 12b the luer connector 12 against the outer tube element 2 axially displaced, depending on the direction of displacement, by the arrows F in the region of the lumen 4 is a widening of the catheter opening or or distal opening 6 according to 1b or narrowing of the catheter opening 6 ' according to 1c ,

In 2 B will schematically show the detailed structure of the catheter 1 to 1a in the expanded state shown in section AA. Here stands the reinforcement layer 9 at least partially in the distal area 6 in to the stiffening of the inner tube member 3 or the outer tube element 2 to effect and a widening of the catheter tip 6 to enable. The gap 5 immediately adjoins the room 6c on, without substantial deformation of the outer tubular element 3 , This condition was achieved by the inner tube element 3 by operation of the inner piece 12b the luer connector 12 (in 2 B not shown) against the outer tube element 2 axially to the distal region 6 has been postponed.

The axial displacement or reciprocation of the inner tube member 3 is schematically represented by the double arrow F and indicates the force on the catheter tip.

In 2c will schematically show the detailed structure of the catheter 1 to 1a in the flattened state shown in section AA. Here stands the reinforcement layer 9 at least partially in the distal area 6 in to the stiffening of the inner tube member 3 to cause and a flattening or flattening of the catheter tip 6 to enable. The gap 5 immediately adjoins the room 6c on, wherein the outer tube element 3 undergoes a significant bulge. This condition was achieved by the inner tube element 3 by operation of the inner piece 12b the luer connector 12 against the outer tube element 2 axially to the distal region 6 has been postponed.

In 3a will schematically show the detailed structure of the catheter 1 to 1a in the initial state shown as a top view and in sectional view AA, wherein the reinforcing layer 9 in the area 6 between the fictitious levels 6b and 6a leaking unilaterally. The connection and the operation of not in the 3a illustrated connectors 12 take place analogously to the description in the 2a - 2c ,

By arranging the in the catheter tip 6 leaking reinforcing layer 9 become either the inner tube element 3 or the outer tube element 2 partially reinforced and when using the connector 12 as before in the 2a - 2c mentioned, the top 6 of the catheter 1 in one by the thrust direction of the connector 12 and the connection of the reinforcing layer to the respective pipe element 2 or 3 certain direction deformed or bent, resulting in 3b is shown schematically by an arrow F _B in section AA.

The invention is not limited to the previously indicated uses and materials and combinations of these, but can also be used for the investigation of other body organs and technical equipment, for example, inspection of cavities hoses and pipes of all kinds are used.

Claims (10)

Catheter ( 1 ) for diagnostic and therapeutic purposes, primarily for use in vascular systems, comprising at least, - an outer tube element ( 2 ), which has a first distal end ( 2 ' ) and a first proximal end ( 2 '' ), - an inner tube element ( 3 ), which has a second distal end ( 3 ' ) and a second proximal end ( 3 '' ) and from the second distal end ( 3 ' ) to the second proximal end ( 3 '' ) extending lumen ( 4 ), wherein - the outer tube element ( 2 ) and the inner tube element ( 3 ) are arranged coaxially to each other and a space ( 5 ), a distal area ( 6 ) with a distal opening ( 6 ' ), an intermediate area ( 7 ) and a proximal region ( 8th ), whereby the distal region ( 6 ) from a first level ( 6a ) to a second level ( 6b ), wherein - the outer tube element ( 2 ) and the inner tube element ( 3 ) at least in a discrete area of the first and second distal ends ( 2 ' . 3 ' ), wherein - the inner tube element ( 3 ) and the outer tube element ( 2 ) are axially displaceable (arranged) to one another and wherein - the distal region ( 6 ) is deformable. Catheter according to claim 1, characterized in that the distal region ( 6 ) by axial displacement of the inner tube element ( 3 ) to the outer tube element ( 2 ) is expandable. Catheter according to claim 1, characterized in that the distal region ( 6 ) by axial displacement of the inner tube element ( 3 ) to the outer tube element ( 2 ) is contractible. Catheter according to claim 1, characterized in that the distal region ( 6 ) by axial displacement of the inner tube element ( 3 ) to the outer tube element ( 2 ) is flattened. Catheter according to one of the preceding claims, characterized in that a reinforcing layer ( 9 ) provided in the space ( 5 ) and in conjunction with the inner tube element ( 3 ) and whereby the catheter in the intermediate area ( 7 ) is stiffened. Catheter according to one of the preceding claims, characterized in that a reinforcing layer ( 9 ) provided in the space ( 5 ) and in connection with the outer tube element ( 2 ) and whereby the catheter in the intermediate area ( 7 ) is stiffened. Catheter according to one of the preceding claims, characterized in that the outer tube element ( 2 ) and / or the inner tube element ( 3 ) and / or the reinforcement layer ( 9 ) is formed in one or more layers and is a woven, knitted fabric, mesh, grid, mesh, nonwoven fabric, fiber strand formations, a spring, a continuous or perforated film or a continuous or perforated hose and the like, as well as combinations thereof. Catheter according to one of the preceding claims, characterized in that the outer tube element ( 2 ) and / or the inner tube element ( 3 ) and / or the reinforcement layer ( 9 ) at least one material of the group comprises: - plastics, preferably TPU, silicone, rubber, PE, PP, PA, preferably nylon or darcon, biopolymers, and mixtures thereof and copolymers and combinations thereof, preferably containing fillers, more preferably calcium carbonate or inorganic fibers , - Metal, for example titanium, stainless steel, preferably biocompatible metal alloys, - ceramic materials, - natural fibers, preferably hemp or cotton. Catheter according to one of the preceding claims, characterized in that the reinforcing layer ( 9 ) in the space ( 5 ) partially over the distal area ( 6 ). Catheter according to one of the preceding claims, characterized in that the distal region ( 6 ) by axial displacement of the inner tube element ( 3 ) to the outer tube element ( 2 ) is bendable.

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