CN116966393A - Ultra-thin wall interventional sheath and manufacturing method thereof - Google Patents

Abstract

The application discloses an ultra-thin wall intervention sheath tube and a manufacturing method thereof, wherein the ultra-thin wall intervention sheath tube comprises a main tube body; the main pipe body is sequentially provided with an inner liner layer, a spring layer and an outer pipe layer from inside to outside; the inner liner is a pipe body made of PTFE, and an adhesion layer is formed on the outer surface of the inner liner pipe body through chemical etching; the spring layer comprises a first spring layer and a second spring layer, and the first spring layer and the second spring layer are formed by winding metal wires; the first spring layer and the second spring layer are mutually embedded and stacked; the outer tube layer is provided with a supporting section, a stabilizing section, a releasing section and a soft section which are gradually reduced in hardness from the proximal end to the distal end in sequence, and the outer tube layer is compounded to the outer surface of the spring layer and the outer surface of the inner liner layer in a flowing mode and is combined into a whole. Under the condition that the inner diameter size meets clinical requirements, the application reduces the outer diameter size of the sheath tube, and has better compliance, stronger bending resistance and support stability.

Description

Ultra-thin wall interventional sheath and manufacturing method thereof

Technical Field

The application relates to the technical field of medical catheters, in particular to an ultra-thin-wall interventional sheath tube and a manufacturing method thereof.

Background

In vascular interventions, there are a number of ways of accessing the instrument, of which the radial and femoral arteries are the main two surgical approaches. Currently, although the femoral artery is the most common surgical approach for cerebral vascular interventions as compared to the radial artery. Only a few cerebral vascular interventional centers began to attempt radial artery access to develop DSA and interventional procedures. In clinical work, radial artery access is often used for coronary intervention. As early as 1989, campeau et al reported for the first time that coronary angiography was performed via radial access, found that this method had few complications, was highly comfortable for the patient and did not affect post-operative beddown activity, until now the radial access had become the conventional access method for coronary angiography. In 2000 Matsumoto et al proposed the concept of trans-radial total cerebral angiography. Although transfemoral approaches are currently very widely used in neuro-interventions, students believe that transradial as a more minimally invasive approach, the severity of complications is far less than transfemoral, and more importantly, patient comfort and acceptability are greatly improved, should be more widely developed and used in cerebral angiography and interventional procedures.

The radial artery access has the following advantages over the femoral artery access: 1. the perineum skin preparation is not needed, so that the psychological discomfort of the patient is reduced, and the preparation is easier to accept by the patient. 2. The tube can be pulled out immediately after the operation, and the movement of other limb joints except the wrist joint at the puncture side is not limited after the operation. This is especially advantageous for elderly patients who are unable to stay in bed. The reduction of the postoperative bedridden braking time has positive significance for reducing the occurrence of deep venous thrombosis of lower limbs. 3. Double circulation of hands: reducing ischemia of the hands; 4. flat bone surface of puncture site without protruding bone: reduce bleeding at the puncture site; the puncture part has no main neurovascular shape change: no risk of nerve damage; 5. fewer complications, in particular obvious reduction of serious complications such as retroperitoneal hematoma, pseudoaneurysm, arteriovenous fistula and the like.

Referring to fig. 1-2, fig. 1 is a schematic view of a radial artery interventional path 1, fig. 2 is a schematic view of a femoral artery interventional path 2, and the following problems still exist in the current radial artery access path:

1. the radial artery is small in size relative to the femoral artery. The average diameter of the radial artery is 2.1-2.6 mm, and most patients are suitable for sheath tubes smaller than 6F. If a larger lumen sheath is used, vasospasm, radial artery occlusion, and patient discomfort or pain can easily occur.

2. The radial artery access path is tortuous. Compared with the femoral artery access, the radial artery access has more curved vascular paths, so the radial artery access requires better compliance and fracture resistance of the sheath, so that the sheath can reach a target position more easily, and bending or other damages do not occur in the process, so that the smooth operation is ensured. This means that conventional sheaths based on femoral artery access designs will not be suitable. The sheath tube applied to the radial artery access can pass through the left radial access and the right radial access, and pass through the left or right collarbone artery and the carotid artery. The sheath tube passing through the radial access is suitable for various use scenes, different vascular bending types need to pass through, the sheath tube is required to have better compliance and folding resistance, the sheath tube can reach a target position more easily, and bending or other damages do not occur in the process, so that the smooth operation is ensured.

3. For a sheath passing through a radial access, the support stability at the arch 3 is required to be higher. The femoral artery access way, the sheath tube from the puncture to the aortic arch 4 and then to the target vascular position, has a complete supporting structure, and ensures certain supporting stability during operation. The radial artery access, the sheath tube from the puncture to the aortic arch 4, the sheath tube has a 'suspended' bottom at the arch part 3, which requires a very strong supporting force of the sheath tube passing through the radial artery access to ensure the supporting stability of the operation in operation. Otherwise, the entire system is easily dropped into the aortic arch 4, so that the operation cannot be smoothly performed.

Disclosure of Invention

In order to overcome the defects of the prior art, the application provides the ultra-thin wall interventional sheath tube and the manufacturing method thereof, which reduce the outer diameter size of the sheath tube and have better compliance, stronger bending resistance and support stability under the condition that the inner diameter size meets clinical requirements.

The application provides an ultra-thin wall interventional sheath, which comprises a main pipe body, wherein the main pipe body is of an elongated pipe structure, and two ends of the main pipe body respectively form a proximal end and a distal end; the main pipe body is sequentially provided with an inner liner layer, a spring layer and an outer pipe layer from inside to outside;

the lining layer is a lining pipe body made of PTFE, and an adhesion layer is formed on the outer surface of the lining pipe body through chemical etching;

the spring layer comprises a first spring layer and a second spring layer, and the first spring layer and the second spring layer are formed by winding metal wires; the first spring layer and the second spring layer are mutually embedded and stacked;

the outer tube layer has set gradually supporting section, stable section, release section and soft section from the proximal end to distal end direction, supporting section, stable section, release section, soft section hardness reduces gradually, outer tube layer rheology complex to spring layer and inner liner surface, with spring layer and inner liner surface combine as an organic wholely.

In a first aspect of the present application, as a preferred embodiment, the first spring layer wires have a first inclination, the first spring layer wires have a first density, and gaps are formed between adjacent wires of the first spring layer;

the inclination of the second spring layer metal wire is a second inclination, the density of the second spring layer metal wire is a second density, and the second spring layer metal wire is embedded into the gap;

the first inclination is not equal to the second inclination in size; the first density is not equal in magnitude to the second density.

In a first aspect of the present application, as a preferred embodiment, the metal wire comprises round wire and/or flat wire made of stainless steel or nickel-titanium alloy; the first gradient and the second gradient are 20-90 degrees, and the first density and the second density are the wire pitch between 0.05-0.6 mm.

In a first aspect of the present application, as a preferred embodiment, the spring layer comprises at least one of an increasing density section or a decreasing density section.

In a first aspect of the present application, as a preferred embodiment, the first spring layer comprises at least one increasing or decreasing density section, and/or the second spring layer comprises at least one increasing or decreasing density section; the density variation range is that the wire pitch is 0.05 mm-0.5 mm.

In the first aspect of the present application, as a preferred embodiment, the method further comprises a braid layer, wherein the braid layer is disposed between the spring layer and the outer tube layer; the braiding layer is formed by braiding a plurality of strands of metal wires through a strong cold drawing process, the metal wires of the braiding layer are round wires and/or flat wires, and the metal wires of the braiding layer are made of nickel-titanium alloy and stainless steel; the number of the braiding layers is 8, 16 or 32, and the braiding density of the braiding layers is preferably 25-120 PPI.

In a first aspect of the present application, as a preferred embodiment, the support section has a first stiffness, and the support section includes three segments for primary support; the stabilizing section has a second hardness, the stabilizing section comprises a segment with good toughness; the release section has a third hardness and comprises two sections for transition; the soft segment has a fourth hardness, and the soft segment comprises two segments and has compliance; the first hardness is greater than the second hardness and the third hardness is greater than the fourth hardness, and the hardness, deformation resistance and compliance of each segment are different.

In a first aspect of the present application, as a preferred embodiment, the surface of the main tubular body is coated with a hydrophilic coating comprising PVP, PAA and PEO; the surface of the main pipe body is subjected to plasma pretreatment to form an activation layer.

In the first aspect of the present application, as a preferred embodiment, the main tube body distal end is provided with a developing ring near the tube orifice, and the main tube body proximal end is provided with a catheter seat and a stress relief member; the main tube body distal end is formed with a sheath tip having a curved shape for selecting a blood vessel.

The second aspect of the present application provides a method for manufacturing an ultra-thin-wall interventional sheath, comprising the steps of:

providing silver-plated copper wires and PTFE liquid materials, immersing the silver-plated copper wires in the PTFE liquid materials, standing for a period of time, rotating, lifting, cooling and forming a film to form an inner liner tube body; treating the surface of the lining pipe body by using a chemical etching process to form an adhesion layer;

providing a plurality of strands of metal wires, and winding the first strand of metal wires on the surface of the lining pipe body at a first inclination and a first density to form a first spring layer; winding a second strand of metal wire at a second inclination and a second density at a gap of the first spring layer to form a second spring layer; the first spring layer and the second spring layer are mutually embedded and stacked to form a spring layer;

weaving the metal wires on the surface of the spring layer through a braiding machine to form a braided net pipe; providing a developing ring, and sleeving the developing ring on a pipe orifice of the woven mesh pipe close to the far end;

providing a plurality of polymer materials with biocompatibility, preparing the polymer materials into a plurality of sections through extrusion equipment based on preset parameters of inner diameter, length, hardness and thickness, connecting the sections according to a preset sequence to form an outer pipe body, rheologically compounding the outer pipe body, the lining pipe body, a spring layer and a woven net pipe body into a whole through integral rheologic, and simultaneously using a stretching reducing clamp to further reduce the wall thickness of the pipe body to obtain a main pipe body;

providing a catheter base and a stress release member; bonding the catheter seat with the near end of the main pipe body through UV photosensitive glue and ultraviolet light; then the stress release piece is assembled on the catheter seat through the bayonet;

the surface of the main pipe is subjected to plasma pretreatment to form an activation layer, and a hydrophilic coating is coated on the surface of the activation layer in a dip-coating mode through coating equipment.

Compared with the prior art, the application has the beneficial effects that:

1. the thickness of the unilateral wall of the ultra-thin wall interventional sheath tube is only 0.004-0.006 inch (0.1016-0.1524 mm). The inner diameter size commonly used in clinic is maintained, and the outer diameter size of the sheath tube is reduced. Taking the typical 6F sheath as an example, the typical inner diameter is 0.088inch (2.2352 mm) and the outer diameter is 0.108inch (2.74 mm). The ultra-thin wall interventional sheath tube has the advantages that on the premise that the inner diameter is kept at 0.088inch (2.2352 mm), the outer diameter is only 0.098-0.100 inch (2.48-2.54 mm), and the characteristic of 'large cavity wall thickness' is realized. At this outer diameter, the diameter of the blood vessel is more suitable for the radial artery, and at least 73% of the vasospasm and the probability of radial artery occlusion are reduced. Meanwhile, the discomfort or pain of the patient is greatly reduced, and the prognosis treatment is obviously improved.

2. The ultra-thin wall interventional sheath tube is specially designed for a section and a structure through a radial path, and has better compliance and stronger fracture resistance. The ultra-thin wall interventional sheath provided by the application has 7-10 different functional sections. Each segment is designed according to the real clinical blood vessel anatomical structure and data, and each segment has different hardness, deformation resistance and compliance. And fully analyze the course and operation of the radial artery access to the target location, matching the best functional segment. Meanwhile, the spring structure of the sheath tube middle layer designs a multi-strand metal wire superposition spring with different inclinations, thereby improving the compliance of the sheath tube and the folding resistance.

3. The ultra-thin wall intervention sheath tube has the advantages that the outer layer of the sheath tube is compounded with reinforced polymer materials and metal woven mesh tubes, so that the sheath tube has very strong supporting stability. In a more challenging tortuous vascular path facing the radial artery access, a powerful push performance can be provided, combined with a better compliance of the sheath, which can smoothly and rapidly deliver the sheath to the target site. Meanwhile, after the sheath tube is in place, the super-strong support stability is provided and maintained, and a stable access system required by the operation is ensured.

Drawings

FIG. 1 is a schematic diagram of a radial artery interventional path in accordance with the background art;

FIG. 2 is a schematic diagram of a femoral artery interventional path in accordance with the background art;

FIG. 3 is a schematic view of the structure of an ultra-thin walled interventional sheath of the present application;

FIG. 4 is a cross-sectional view of a cross-section of an ultra-thin walled interventional sheath A-A of the present application;

FIG. 5 is a cross-sectional view of a cross-section A-A of another embodiment of an ultra-thin walled interventional sheath of the present application;

FIG. 6 is a schematic view of the structure of the straight sheath tip of the ultra thin walled interventional sheath of the present application;

FIG. 7 is a schematic view of the structure of a bent sheath tip of an ultra-thin walled interventional sheath of the present application;

FIG. 8 is a schematic view of the structure of the head end of another bent sheath of the ultra-thin wall interventional sheath of the present application;

FIG. 9 is a schematic view of the use of the head end of each bent pin tube of the ultra-thin walled interventional sheath of the present application;

FIG. 10 is a schematic view of the structure of the spring layer of the ultra-thin walled interventional sheath of the present application;

FIG. 11 is a schematic structural view of the braid of the ultra-thin walled interventional sheath of the present application.

In the figure: 1. a radial artery interventional path; 2. a femoral artery interventional path; 3. a bow; 4. aortic arch; 100. a main pipe body; 110. an inner liner layer; 120. a spring layer; 121. a first spring layer; 1211. a void; 122. a second spring layer; 130. a braiding layer; 140. an outer tube layer; 141. a support section; 142. a stabilizing section; 143. a release section; 144. a soft section; 600. a sheath head end; 600a, a bent sheath head end of the SIM 1; 600b, a bent sheath head end of the SIM 2; 600c, a bent sheath head end of the SIM 3; 600d, VTK bent sheath head end; 600e, H1 bent sheath head end; 600f, H2 bent sheath head end; 700. a stress relief; 800. a catheter holder; 900. and a developing ring.

Detailed Description

The application will be further described with reference to the drawings and the detailed description, wherein it should be noted that, on the premise of no conflict, the embodiments or technical features described below can be arbitrarily combined to form new embodiments. Materials and equipment used in this example are commercially available, except as specifically noted. Examples of embodiments are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements throughout or elements having like or similar functionality. The embodiments described below by referring to the drawings are exemplary only for explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. In the description of the present application, the meaning of "a plurality" is two or more, unless specifically stated otherwise.

In the description of the present application, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be fixedly connected, or may be connected through an intermediary, or may be connected between two elements or may be an interaction relationship between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

The terms first, second and the like in the description and in the claims and in the above-described figures, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Example 1:

referring to fig. 3-11, the present embodiment provides an ultra-thin-wall interventional sheath, which belongs to the field of medical catheters, is specially designed for radial artery access, and can be used for other access, including but not limited to the following usage scenarios: the interventional or diagnostic devices are introduced into the peripheral, coronary and neurovascular systems through radial or femoral arteries and other vascular access, helping the devices reach the lesion site and maintaining the stability of the devices during the procedure.

An ultra-thin-wall interventional sheath of the present embodiment includes a main tube body 100, the main tube body 100 is of an elongated tube structure, two ends of the main tube body 100 respectively form a proximal end and a distal end, a developing ring 900 is mounted on the distal end of the main tube body 100 near a tube orifice, and a catheter holder 800 and a stress release member 700 are mounted on the proximal tube body. The whole length of the interventional sheath tube is 40 cm-155 cm; the main tube body 100 of this example has an inner diameter of 0.056 to 0.109inch (1.42 to 2.77 mm), and the main tube body 100 has an outer diameter of 0.066 to 0.121inch (1.68 to 3.07 mm).

Referring to fig. 6-9, the distal end of the main body 100 is formed with a sheath tip 600. The sheath tip 600 may have a different curved shape in order to facilitate the selection of vessels, such as the internal carotid artery, subclavian artery, etc., at the aortic arch to facilitate the physician's rapid advancement of the sheath to the target site. The sheath tip 600 may be a straight tip, and is deformed by a user under specific conditions, and fig. 7 shows an MP-bent sheath tip 600, where the sheath tip 600 has a bending portion forming an angle of 135 ° to 150 ° with the main tube body 100, and the bending portion has a length of 13±2mm; fig. 8 shows a SIM 1-bent type sheath tip 600a, a SIM 2-bent type sheath tip 600b, a SIM 3-bent type sheath tip 600c, a VTK-bent type sheath tip 600d, an H1-bent type sheath tip 600e, and an H2-bent type sheath tip 600f in this order; wherein, the ends of the sheath tube head end 600a of the SIM1 bent type, the sheath tube head end 600b of the SIM2 bent type and the sheath tube head end 600c of the SIM3 bent type form back buckling parts which are approximately parallel to the direction of the main tube body 100, and the lengths of the back buckling parts are 40+/-10 mm, 70+/-10 mm and 85+/-10 mm respectively; specifically, the SIM1 curve, the SIM2 curve and the SIM3 curve are different in curve extension length under the condition of uniform curve, and the SIM curve is specially used for the conventional super-selection operation of the radial artery access. The curve is suitable for the neural intervention operation of the left carotid artery through the right radial intervention. Of which the most common procedure is descending aortic loop formation.

The VTK-bent sheath tip 600d, the H1-bent sheath tip 600e, and the H2-bent sheath tip 600f have flat folds approximately perpendicular to the main tube body 100, and the lengths of the flat folds are 40±10mm, 30±10mm, and 70±10mm, respectively; the user selects the model according to the actual conditions of different access ways so as to meet the demands of various vascular structures on the head end. The VTK curve, HI curve and H2 curve are different curve-type contrast catheters for femoral artery intervention, and the curve is suitable for femoral artery intervention to perform superselection operation in the arch. H1 is mainly used in young patients or patients with slight tortuosity of the aortic arch, and H2 is selected if the aortic arch is significantly elongated.

The main pipe body 100 is provided with an inner liner layer 110, a spring layer 120, a woven layer 130, an outer pipe layer 140 and a hydrophilic coating in sequence from inside to outside;

the inner liner 110 is a liner tube made of PTFE (polytetrafluoroethylene), and the inner diameter of the liner tube is 0.056-0.109 inch (1.42-2.77 mm). The inner surface of the lining pipe body made of PTFE through a dip-coating process is flat and has lubricity, which is beneficial for other instruments to pass through. The adhesive layer is formed on the outer surface of the lining pipe body through chemical etching and a reinforcing technology process, and the adhesive effect between the lining layer 110 and other layers of materials is enhanced through the arrangement of the adhesive layer on the outer surface of the lining pipe body; through the scheme, the holding capacity and the tearing resistance of the lumen are improved, and the lumen can be kept in an intact and smooth state.

The spring layer 120 is mainly composed of a plurality of superimposed round wires and flat wires of metals such as stainless steel, nickel-titanium alloy and the like, and is used as an intermediate layer for improving the mechanical property of the catheter. The compliance, torsion control and deformation resistance of the catheter are improved.

The spring layer 120 includes a first spring layer 121 and a second spring layer 122, and the first spring layer 121 and the second spring layer 122 have different slopes and different densities and are in a state of being mutually embedded and stacked. Specifically, the first spring layer 121 has a wire pitch of a first pitch; the density of the wires of the first spring layer 121 is a first density; gaps 1211 are formed between adjacent wires of the first spring layer 121; the second spring layer 122 has a second wire pitch; the density of the wires of the second spring layer 122 is a second density, and the wires of the second spring layer 122 are disposed in the gaps 1211. Wherein the first inclination and the second inclination are preferably 20-90 degrees, and the first density and the second density are preferably 0.05-0.6 mm of the wire pitch. According to the implementation, the metal wires of multiple strands are arranged in the mutually embedded and stacked state with different inclinations and different densities, so that the radial space is greatly reduced and the wall thickness of the pipe body is greatly reduced on the premise of providing the same mechanical property.

The number of the spring layers 120 is preferably 2-4, and after the strands of metal wires are respectively formed at different inclinations and different densities, the multi-layer spring layers 120 are formed by superposition, and the spring layers 120 are formed by mutually embedding and stacking.

Further, the spring layer 120 includes at least one increasing or decreasing density segment, which may be that the first spring layer 121 includes at least one increasing or decreasing density segment, or the second spring layer 122 includes at least one increasing or decreasing density segment, and the first spring layer 121 and the second spring layer 122 each include at least one increasing or decreasing density segment; the density of the spring layer 120 is increased or decreased by the overlapping nesting of the first spring layer 121 and the second spring layer 122. By providing the spring layer 120 with a graded density, the stresses acting on the sheath can be more evenly distributed, helping the main body 100 to balance the impact from all directions, enhancing the fracture resistance. The inclination of the wire of the first spring layer 121in this embodiment is set to 90 °, the inclination of the wire of the second spring layer 122 is set to 50 °, and the density gradient range of the first spring layer 121 and the second spring layer 122 is increased from 0.05mm to 0.5mm, so as to more adapt to the operation implementation requirement of radial artery access.

Referring to fig. 10, the braid 130 is formed by braiding a plurality of wires, which may be round wires or flat wires, through a strong cold drawing process, and the material is preferably nickel-titanium alloy or stainless steel. Braid 130 acts primarily as a woven mesh tube to increase the strength of the catheter. The number of ingots is preferably 8, 16 or 32, and the braiding density is preferably 25 to 120PPI. Therefore, the supporting force of the sheath tube is stronger, and the pushing force is transmitted more efficiently and uniformly.

The outer tube layer 140 is made of a biocompatible polymer material, including reinforced Nylon (polycaprolactam powder), pebax (polyether amide resin), TPU (polyurethane), PC (polycarbonate), and the like, thereby forming a plurality of functional segments, each segment having different hardness, deformation resistance, and compliance.

The outer tube layer 140 of the present embodiment is sequentially provided with a supporting section 141, a stabilizing section 142, a releasing section 143 and a soft section 144 from the proximal end to the distal end, wherein the hardness of the supporting section 141, the stabilizing section 142, the releasing section 143 and the soft section 144 is gradually reduced; the outer tube layer 140 is rheologically compounded into the inner liner layer 110, the spring layer 120 and the braid 130, such that the outer tube layer 140, the inner liner layer 110, the spring layer 120 and the braid 130 are integrated.

Specifically, the support section 141 has a first stiffness, and the support section 141 includes three sections that provide the primary support function, and more efficient transfer of pushing forces during pushing, and support of the entire instrument system after the sheath reaches the target site, providing stability of the sheath path. The stabilizing section 142 has a second hardness, and the stabilizing section 142 includes a segment with good toughness to provide better stability to rocking and sliding of the sheath during pushing or cornering. The release section 143 has a third hardness, and the release section 143 includes two segments, which play a role in transition for releasing stress generated during pushing and tension generated during turning of the sheath tip 600. The flexible segment 144 has a fourth hardness, the flexible segment 144 comprises two segments, the outer diameter of the flexible segment is smaller, the flexible segment has super-strong compliance, the flexible segment can conform to the bending of various blood vessels, the bending is flexible, the sheath tube can smoothly pass through the blood vessels to reach the target position, the smoothness is high, the first hardness is larger than the second hardness and larger than the third hardness and larger than the fourth hardness, and each segment has different hardness, deformation resistance and compliance. This embodiment fully combines the procedure and operation of radial access to the target site, matching and distributing the optimal functional segments. Can better conform to the complicated vascular tortuous path in the body, smoothly and rapidly transfer to the target position, provide and maintain the ultra-strong support stability, and ensure the stable access system required by the operation.

In some preferred embodiments, the surface of the main tubular body 100 is coated with a hydrophilic coating consisting essentially of PVP (polyvinylpyrrolidone), PAA (acrylic resin), PEO (oxidized polyethylene). By providing a hydrophilic coating on the surface of the outer tube layer 140, the influence of the surface friction force of the tube body is eliminated, and the surface friction force of the tube body can be less than 0.3N, so that the conveying resistance of the sheath tube in the blood vessel is greatly reduced. Further, the surface of the main pipe body 100 is subjected to plasma pretreatment to form an activation layer, and the surface characteristics of the main pipe body 100 are improved by plasma technology treatment, so that the adhesion firmness of the coating is enhanced, and the sheath is kept lubricated all the time. Further, the hydrophilic coating also includes an anticoagulant, further preventing thrombus formation.

The developing ring 900 is arranged at the position, close to the pipe orifice, of the far end of the main pipe body 100, and the main pipe body 100 can be provided with the developing ring 900 in a full-segment manner to realize full-segment development; the developing ring 900 is mainly made of platinum iridium alloy, the developing ring 900 is used as a marking belt of a sheath tube, and the position and the direction of a distal tube orifice can be obviously observed under X-ray, so that the operation of a surgery is facilitated.

Catheter hub 800 is disposed on the proximal body, catheter hub 800 is made primarily of a hard material such as PC, PVC, nylon, and catheter hub 800 has a standard 6% luer fitting, which may be used as a sheath connector for introducing other instruments or for connecting other instruments with similar luer fittings. Such as hemostatic valves, syringes, extension tubing, and powered syringes.

The stress release member 700 is provided between the catheter hub 800 and the main tube body 100, is mainly made of soft materials such as TPE and silicone rubber, has a taper of 8 ° to 33 °, and is used as a stress release member between the catheter hub 800 and the main tube body 100, thereby improving the stress concentration between the catheter hub 800 and the main tube body 100 and preventing the main tube body 100 from being kinked accidentally.

When in use, the interventional sheath is assembled with other needed accessories, such as a hemostatic valve, a syringe, an extension tube or a power syringe, etc. for standby. After puncturing the radial artery vessel using sterile manipulation techniques, a guidewire of 0.035 inches or 0.038 inches and other suitable guidewire is left behind. The assembled interventional sheath is advanced along the guidewire and through the tissue into the vessel. The vessel path is selected under X-ray fluoroscopy using a contrast catheter or guidewire, and the catheter is advanced along the guidewire or contrast catheter to the desired vessel location. Other guidewires, catheters, or other interventional instruments are delivered along the established access system of the present interventional sheath for diagnostic or therapeutic procedures, as desired clinically.

The interventional sheath of the embodiment not only improves the compliance of the sheath, but also improves the folding resistance by setting the metal wires of the first spring layer 121 and the second spring layer 122 to different slopes, different densities and in a mutually embedded and stacked state; and the integral rheological technology is combined with the rheological composition of the outer pipe layer 140, so that the adhesion and bonding effect is better, the radial space is greatly reduced on the premise of providing the same mechanical property, and the wall thickness of the pipe body is greatly reduced. The single-side wall thickness of the interventional sheath tube of the embodiment is only 0.004-0.006 inch (0.10-0.15 mm), so that the clinically common inner diameter size is maintained, and the outer diameter size is reduced. Taking the typical 6F sheath as an example, the typical inner diameter is 0.088inch (2.24 mm) and the outer diameter is 0.108inch (2.74 mm). The scheme of the embodiment realizes the sheath tube of the ultra-thin wall technology, and the inner diameter of the sheath tube is kept at 0.088inch (2.24 mm), the outer diameter is only 0.098-0.100 inch (2.48-2.54 mm), and the characteristic of large cavity wall thickness is realized. At this outer diameter, the diameter of the blood vessel is more suitable for the radial artery, and at least 73% of the vasospasm and the probability of radial artery occlusion are reduced. Meanwhile, the discomfort or pain of the patient is greatly reduced, and the prognosis treatment is obviously improved. Secondly, the interventional sheath of the embodiment fully combines the process and operation of the radial artery access to the target position, and is provided with a plurality of segments such as a supporting segment 141, a stabilizing segment 142, a releasing segment 143, a soft segment 144 and the like, wherein each segment is matched with different segments, and each segment is designed according to the real clinical blood vessel anatomical structure and data through 7-10 different functional segments, and has different hardness, deformation resistance and compliance; and fully analyze the radial artery access to the process of the target location and operate the optimally matched functional segment, guaranteed compliance and support stability that the operation process needs at the same time, make the sheath can be conveyed to the target location smoothly and fast.

The outer tube layer 140 of the interventional sheath of the present embodiment has reinforced polymer material and the braid 130 through the composite flow, so that the sheath has very strong supporting stability. In a more challenging tortuous vascular path facing the radial artery access, a powerful push performance is provided, combined with a better compliance of the sheath, which enables smooth and rapid delivery of the sheath to the target site. Meanwhile, after the sheath tube is in place, the super-strong support stability is provided and maintained, and a stable access system required by the operation is ensured.

Example 2:

the present embodiment provides a method for manufacturing an ultra-thin-wall interventional sheath, which is mainly used for manufacturing an ultra-thin-wall interventional sheath as in embodiment 1, and includes the following steps:

s1 dip coating and etching steps of the inner liner 110:

a PTFE liquid material with high lubricity and a silver-plated copper wire with a diameter of 0.056-0.109 inch (1.4224-2.7686 mm) are provided, and the silver-plated copper wire is straightened and clamped and lifted on dip-coating equipment. After equipment is started, the silver-plated copper wire is immersed into liquid PTFE, kept stand and stable for 2-5 min, lifted up at the speed of 0.04-0.46 mm/s, cooled to form a lining pipe body, and the surface of the lining pipe body is treated by a chemical etching process to form an adhesion layer with high adhesion.

S2, winding and stacking of the spring layer 120:

providing round wires and flat wires of metals such as stainless steel, nickel-titanium alloy and the like, wherein the size of the metal wires is 0.001-0.006 inch (0.03-0.15 mm), the number of strands is 2-4, and the wires are wound on the surface of an inner layer pipe body through winding equipment; setting the gradient range to 20-90 degrees, and the density to 0.05-0.6 mm, coiling to form a first spring layer 121, and then using a second strand or other strands of metal wires, setting different gradients and different densities through coiling equipment, and overlapping the second spring layer 122 and the rest spring layers in the gaps 1211 of the first spring layer 121. Finally, forming the multi-strand spring layers which are mutually embedded and stacked.

S3 braiding of braid 130:

round and flat wires of nickel-titanium alloy, stainless steel and other metals manufactured through a reinforced cold drawing process are provided, the wire size is 0.001-0.006 inch (0.0254-0.1524 mm), the number of ingots is preferably 8, 16 and 32, and the braiding density is 25-120 PPI. After forming a uniform woven mesh tube on the surface of the spring layer 120 by a braiding machine, cutting is performed at the position of a woven tube orifice, and the developing ring 900 made of platinum iridium alloy is sleeved.

S4 rheological compounding of the outer tube layer 140:

the reinforced Nylon, pebax, polyurethane TPU, PC and other biocompatible polymer materials are provided, and are prepared through a plunger type extrusion or screw type extrusion device by preset parameters to form a plurality of sections, wherein each section has different inner diameters, lengths, hardness and thickness. The segments are joined to form an outer layer pipe body, the inner liner layer 110, the spring layer 120 and the woven layer 130 are subjected to rheological compounding to form a whole body through an integral rheological technology, and in the rheological process, a stretching reducing clamp is used to further reduce the pipe wall thickness, so that a main pipe body 100 is obtained;

specifically, the raw materials are preheated and dried and then plasticized, namely, solid polymer granules are heated in an extruder, and the solid polymer granules become viscous state materials by means of internal friction heat among the polymer materials. The preferable temperature is 180-290 ℃ and the pressure is less than or equal to 55Mpa. And then forming the material, and forming the viscous fluid material formed by plasticizing into a continuous section through a die with a certain shape under the rotary pushing action of the extruder screw. The corresponding key technological parameters, preferably the helix angle of 12.8-29.1 degrees, are finally shaped, so that the extruded continuous section is cooled and shaped into a pipe product, namely a single-cavity or multi-cavity pipe body is formed and used as the outer layer material of the catheter. The components may have different inside diameters, lengths, hardness, thickness, etc. gauge sizes. The number of the functional sections is 7-10, and the hot air type welding technology is adopted to enable the sections to be connected. Finally, the materials of the outer layer are softened under the temperature of 220-378 ℃ by the integral rheological technology, and the inner liner layer 110, the spring layer 120, the woven layer 130 and the outer tube layer 140 are rheologically compounded to form a complete tube body. Meanwhile, in the rheological process, a stretching reducing clamp is used, so that the wall thickness of the pipe body is further reduced.

S5 adhesive assembly of catheter hub 800 and strain relief 700:

providing a catheter hub 800 and a strain relief 700; catheter hub 800 is made of a hard material such as PC, PVC, nylon with a standard 6% luer fitting, stress relief 700 is made of a soft material such as TPE, silicone, etc., with a taper of 8-33 degrees; bonding the catheter hub 800 to the proximal end of the main catheter body 100 by UV light with UV light sensitive glue; the strain relief 700 is then bayonet-fitted to the catheter hub 800.

S6, coating of a hydrophilic coating:

the surface of the main pipe body 100 is subjected to plasma pretreatment to form an activation layer, the pipe orifices at the two ends of the main pipe body 100 are plugged with silica gel plugs, then the main pipe body 100 is hung on a chuck of a coating device, the whole main pipe body 100 is immersed into a hydrophilic coating solution, lifted and lifted at a slow speed of 0.11-0.82 mm/s, and finally ultraviolet light is used for irradiating for 1-10 minutes to solidify the coating.

The above embodiments are only preferred embodiments of the present application, and the scope of the present application is not limited thereto, but any insubstantial changes and substitutions made by those skilled in the art on the basis of the present application are intended to be within the scope of the present application as claimed.

Claims (10)

1. An ultra-thin wall interventional sheath, comprising a main tube body, wherein the main tube body is of an elongated tube structure, and two ends of the main tube body respectively form a proximal end and a distal end; the main pipe body is sequentially provided with an inner liner layer, a spring layer and an outer pipe layer from inside to outside;

the lining layer is a lining pipe body made of PTFE, and an adhesion layer is formed on the outer surface of the lining pipe body through chemical etching;

the spring layer comprises a first spring layer and a second spring layer, and the first spring layer and the second spring layer are formed by winding metal wires; the first spring layer and the second spring layer are mutually embedded and stacked;

the outer tube layer has set gradually supporting section, stable section, release section and soft section from the proximal end to distal end direction, supporting section, stable section, release section, soft section hardness reduces gradually, outer tube layer rheology complex to spring layer and inner liner surface, with spring layer and inner liner surface combine as an organic wholely.

2. The ultra-thin walled interventional sheath of claim 1, wherein the pitch of the first spring layer wires is a first pitch, the density of the first spring layer wires is a first density, and gaps are formed between adjacent wires of the first spring layer;

the inclination of the second spring layer metal wire is a second inclination, the density of the second spring layer metal wire is a second density, and the second spring layer metal wire is embedded into the gap;

the first inclination is not equal to the second inclination in size; the first density is not equal in magnitude to the second density.

3. An ultra-thin walled interventional sheath according to claim 2, wherein the wires comprise round and/or flat wires made of stainless steel or nitinol; the first gradient and the second gradient are 20-90 degrees, and the first density and the second density are the wire pitch between 0.05-0.6 mm.

4. The ultra-thin walled interventional sheath of claim 2, wherein the spring layer comprises at least one of an increasing density section or a decreasing density section.

5. The ultra-thin walled interventional sheath of claim 4, wherein the first spring layer comprises at least one of an increasing density section or a decreasing density section and/or the second spring layer comprises at least one of an increasing density section or a decreasing density section; the density variation range is that the wire pitch is 0.05 mm-0.5 mm.

6. The ultra-thin walled interventional sheath of claim 1, further comprising a braid disposed between the spring layer and the outer tube layer; the braiding layer is formed by braiding a plurality of strands of metal wires through a strong cold drawing process, the metal wires of the braiding layer are round wires and/or flat wires, and the metal wires of the braiding layer are made of nickel-titanium alloy and stainless steel; the number of the braiding layers is 8, 16 or 32, and the braiding density of the braiding layers is preferably 25-120 PPI.

7. An ultra-thin walled interventional sheath according to claim 1, wherein the support section has a first stiffness, the support section comprising three sections for primary support; the stabilizing section has a second hardness, the stabilizing section comprises a segment with good toughness; the release section has a third hardness and comprises two sections for transition; the soft segment has a fourth hardness, and the soft segment comprises two segments and has compliance; the first hardness is greater than the second hardness and the third hardness is greater than the fourth hardness, and the hardness, deformation resistance and compliance of each segment are different.

8. The ultra-thin walled interventional sheath of claim 1, wherein the primary tubular body surface is coated with a hydrophilic coating comprising PVP, PAA and PEO; the surface of the main pipe body is subjected to plasma pretreatment to form an activation layer.

9. The ultra-thin walled interventional sheath of claim 1, wherein the distal end of the main tube body is provided with a developing ring near the orifice and the proximal end of the main tube body is provided with a catheter hub and a stress relief; the main tube body distal end is formed with a sheath tip having a curved shape for selecting a blood vessel.

10. A method for manufacturing an ultra-thin wall interventional sheath is characterized by comprising the following steps,

providing silver-plated copper wires and PTFE liquid materials, immersing the silver-plated copper wires in the PTFE liquid materials, standing for a period of time, rotating, lifting, cooling and forming a film to form an inner liner tube body; treating the surface of the lining pipe body by using a chemical etching process to form an adhesion layer;

providing a plurality of strands of metal wires, and winding the first strand of metal wires on the surface of the lining pipe body at a first inclination and a first density to form a first spring layer; winding a second strand of metal wire at a second inclination and a second density at a gap of the first spring layer to form a second spring layer; the first spring layer and the second spring layer are mutually embedded and stacked to form a spring layer;

weaving the metal wires on the surface of the spring layer through a braiding machine to form a braided net pipe; providing a developing ring, and sleeving the developing ring on a pipe orifice of the woven mesh pipe close to the far end;

providing a plurality of polymer materials with biocompatibility, preparing the polymer materials into a plurality of sections through extrusion equipment based on preset parameters of inner diameter, length, hardness and thickness, connecting the sections according to a preset sequence to form an outer pipe body, rheologically compounding the outer pipe body, the lining pipe body, a spring layer and a woven net pipe body into a whole through integral rheologic, and simultaneously using a stretching reducing clamp to further reduce the wall thickness of the pipe body to obtain a main pipe body;

providing a catheter base and a stress release member; bonding the catheter seat with the near end of the main pipe body through UV photosensitive glue and ultraviolet light; then the stress release piece is assembled on the catheter seat through the bayonet;

the surface of the main pipe is subjected to plasma pretreatment to form an activation layer, and a hydrophilic coating is coated on the surface of the activation layer in a dip-coating mode through coating equipment.