CN113893073A - Recyclable sheath pipe assembly and processing method - Google Patents

Abstract

The application discloses a recoverable sheath pipe assembly and a processing method, the recoverable sheath pipe assembly comprises a sheath pipe and a sheath core assembly which are matched in a sliding nesting mode, the sheath core assembly comprises a core pipe, a locking piece used for connecting an interventional instrument is installed at the far-end position of the core pipe, the sheath pipe is located at the periphery of the sheath core assembly, the core pipe comprises a compliance section adjacent to the locking piece and a second extension section which is butted with the compliance section and extends towards the near end, and the compliance section has smaller rigidity than the second extension section; sheath pipe is divided into loading section, suitable curved section and first extension section by distal end to near-end in proper order in the axial, wherein it is used for accomodating intervention apparatus to load the section, the sheath pipe adopts multilayer structure.

Description

Recyclable sheath pipe assembly and processing method

Technical Field

The invention belongs to the technical field of medical instruments, and particularly relates to a recyclable sheath tube assembly convenient for conveying an interventional instrument and a processing method.

Background

Interventional device conveying system generally includes sheath pipe subassembly, and sheath pipe subassembly includes sheath core subassembly and slides the sheath pipe of cover in sheath core subassembly outside, and human vasculature can be got into to both distal ends, and the near-end is connected with operating handle, and based on the circuitous tortuous characteristic of human vasculature and the consideration of remote operation, axial support and the compliance of sheath pipe subassembly distal end need be compromise.

Disclosure of Invention

The application provides a recoverable sheath assembly, comprising a sheath tube and a sheath core assembly which are matched in a sliding nesting mode, wherein the sheath core assembly comprises a core tube, a locking piece used for connecting an interventional instrument is installed at the far-end part of the core tube, the sheath tube is positioned at the periphery of the sheath core assembly, the core tube comprises a compliance section adjacent to the locking piece, and a second extension section which is butted with the compliance section and extends towards the near end, and the compliance section has smaller rigidity than the second extension section;

sheath pipe is divided into loading section, suitable curved section and first extension section by distal end to near-end in proper order in the axial, wherein the loading section is used for accomodating intervention apparatus, the sheath pipe adopts multilayer structure, includes:

the inner sheath pipe is distributed on the bending section and the first extending section in the axial direction;

the lining pipe is butted at the far end of the inner sheath pipe and is distributed on the loading section in the axial direction;

the metal pipe wraps the distal end part of the inner sheath pipe and the periphery of the inner lining pipe, and is distributed on the bending section and the loading section in the axial direction;

the outer wrapping film is wrapped on the periphery of the metal pipe and is distributed on the bending section and the loading section in the axial direction.

Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative being combinable individually for the above general solution or among several alternatives without technical or logical contradictions.

Optionally, the periphery of the locking piece is provided with a limiting groove for connecting an interventional instrument, the proximal end part of the interventional instrument is clamped into the limiting groove in a loading state, and the axial position of the interventional instrument is limited by the limiting groove.

Optionally, the periphery of latch fitting is fixed with each spacing groove complex layering, and the layering is restricted by the sheath pipe and is in with the near-end position restriction of interveneeing the apparatus the spacing inslot.

Optionally, the pressing strip is made of a flexible material. Optionally, the metal pipe includes a head pipe, a main pipe and an extension pipe that are sequentially butted from a far end to a near end, wherein in an axial direction, the head pipe and the main pipe are uniformly distributed in the loading section, and the extension pipe is distributed in the bending section.

Optionally, the head end tube includes a body section, 3-6 expansion pieces circumferentially spaced apart on a distal side of the body section, and a first connector on a proximal side of the body section, and the distal side of the body tube has a second connector, and the first connector and the second connector are engaged with each other and have complementary shapes.

Optionally, each expansion piece is provided with a hollow area, the hollow area is a plurality of through holes arranged at intervals along the axial direction of the sheath, and the total area of the through holes on each expansion piece is smaller than 50% of the area of the expansion piece.

Alternatively, the area of the through hole is larger the closer to the distal end on the same expansion sheet.

Optionally, the through holes are circular or oval, and the number of the through holes on the same expansion piece is 2-5.

Optionally, the expansion pieces are evenly distributed along the circumferential direction, and the number of the expansion pieces is 3-6.

Optionally, the first connector is T-shaped.

Optionally, the main body section forms a developing area in a hollow manner, and the developing area is used for installing a developing point.

Optionally, through holes are distributed on the body section and the first connector, and the lining pipe and the outer coating film are mutually fused at the through holes.

Optionally, each expansion sheet is provided with a hollow-out area; the hollow-out area is a strip-shaped hole which axially extends along the head end pipe.

Optionally, on the same expansion piece, two strip-shaped holes are provided.

Optionally, the strip-shaped holes extend with equal width.

Optionally, the two ends of the strip-shaped hole in the length direction are arc-shaped inner edges.

Optionally, a gap is formed between two adjacent expansion pieces, each expansion piece is provided with a narrowing portion at a proximal end portion, and the gap is provided with a widening portion corresponding to the narrowing portion at the proximal end portion.

Optionally, the inner edge of the widened portion is a smooth curve.

Optionally, the central region in the length direction of the spaced opening extends with equal width.

Optionally, the width of the equal-width extending part of the spaced opening is substantially the same as the width of the strip-shaped hole.

Optionally, the proximal side of the strip-shaped hole crosses over the narrowed part of the expansion sheet.

Optionally, the narrow part of the expansion piece is crossed by the near end side of the strip-shaped hole by 1-5 mm.

Optionally, the distal end of the expansion piece has a smooth outer edge.

Optionally, the head end pipe is formed by cutting a nickel-titanium alloy pipe, and the main body pipe and the extension pipe are formed by cutting stainless steel pipes.

Optionally, the extension tube is a hypotube.

Optionally, the core tube includes a compliant segment adjacent the locking element and a second extension segment abutting the compliant segment and extending proximally, the compliant segment having a lesser stiffness than the second extension segment.

Optionally, the core tube is a whole hypotube;

or the compliant section adopts a hypotube, and the second extension section adopts a steel cable tube made of metal wires.

Optionally, the length of the compliant section is 120 mm-180 mm.

Optionally, the compliant section carries a first stiffening rib extending in the axial direction.

Optionally, the inner sheath tube has a multilayer structure, and two second reinforcing ribs extending in the axial direction are arranged in the interlayer, wherein one of the two second reinforcing ribs is located at the same circumferential position as the first reinforcing rib, and the other second reinforcing rib is 180 degrees different from the circumferential position of the first reinforcing rib.

Optionally, the inner sheath tube is sequentially an inner layer, a braided layer and an outer layer from inside to outside, wherein the second reinforcing rib is located in the braided layer.

Optionally, the core tube includes a compliant segment adjacent the locking element, and a second extension segment abutting the compliant segment and extending proximally; the compliant section is provided with a first reinforcing rib extending along the axial direction;

a third reinforcing rib extending along the axial direction is arranged in the extension pipe, and the third reinforcing rib is one and is positioned at the same circumferential position as the first reinforcing rib; or two third reinforcing ribs are arranged, one third reinforcing rib is located at the same circumferential position as the first reinforcing rib, and the other third reinforcing rib is 180 degrees different from the first reinforcing rib in circumferential position.

Optionally, the inner sheath tube includes a distal portion in the curvable section, and a proximal portion in the first extension section, wherein the distal portion has a lesser stiffness than the proximal portion.

The application also provides a processing method of the recyclable sheath pipe assembly, which comprises the steps of respectively providing the sheath pipe assembly and the sheath pipe and assembling, wherein the processing method of the sheath pipe comprises the following steps:

step S100, providing an inner sheath tube and processing the distal end of the inner sheath tube to form a flaring part;

step S200, fixedly sleeving a lining pipe on the periphery of the flaring part;

step S300, sleeving a metal pipe on the periphery of the distal end part of the inner sheath pipe and the periphery of the lining pipe;

and S400, coating the outer surface of the metal pipe by sections by using an outer coating material, and forming an outer coating film integrally after the outer coating material of each section is hot-melted.

The sheath may be the sheath of the present application.

Optionally, in step S200, the proximal end of the inner liner tube has a plurality of lugs arranged at intervals along the circumferential direction, the plurality of lugs are overlapped and wrapped around the periphery of the flared portion, and then the plurality of lugs are wrapped by the fixing sleeve and then fixed by hot melting.

Optionally, the lugs are uniformly arranged in the circumferential direction by 3-6.

Optionally, the lining pipe is made of a polymer material.

Optionally, the lining pipe is made of PTFE.

Optionally, the fixing sleeve is made of a polymer material different from the lining pipe.

Optionally, the fixing sleeve is made of Pebax.

Optionally, step S400 specifically includes:

step S410, wrapping a first connecting sleeve at the butt joint part of the main body pipe and the head end pipe, wrapping a head end outer sleeve at the head end pipe, and fixing the first connecting sleeve and the head end outer sleeve in a hot melting way;

step S420, wrapping the main body outer sleeve on the periphery of the main body pipe and fixing the main body outer sleeve in a hot melting mode;

step S430, wrapping a second connecting sleeve at the proximal end of the extension tube and the inner sheath tube at the adjacent position, and fixing the second connecting sleeve in a hot melting manner;

and step S440, wrapping the connecting sleeve on the periphery of the extension pipe and performing hot melting and fixing.

Optionally, the main tube has hollow areas at intervals, guide ribs are formed between adjacent hollow areas, and in step S420, before the main tube is wrapped by the main jacket, a gasket is placed in each hollow area and is fixed by hot melting.

Optionally, the liner is made of Pebax.

Optionally, the head end outer sleeve and the connecting sleeve are made of TPU.

Optionally, the first connecting sleeve, the second connecting sleeve and the main body casing are all made of Pebax material.

In this application, through the improvement to the sheath pipe structure for recoverable sheath pipe subassembly more can adapt to complicated intervention route, has also kept good mechanical properties.

Drawings

FIG. 1 is a schematic diagram of the construction of a conveyor system according to the present application;

FIG. 2a is a schematic view of a core tube assembly according to an embodiment of the present invention;

FIG. 2b is a schematic view of a core tube assembly according to an embodiment of the present invention;

FIG. 3a is a schematic view of a locking element according to an embodiment of the present application;

FIG. 3b is a schematic view of a locking element according to an embodiment of the present application;

FIG. 4 is a schematic view of a core tube assembly according to an embodiment of the present invention in which the locking member is in a line-by-wire configuration;

FIG. 5 is a schematic illustration of the locking element of FIG. 4 engaged with the access instrument;

FIG. 6 is a schematic view of the core tube (compliant section) according to an embodiment of the present invention;

FIG. 7 is a schematic view of the core tube (compliant section) of FIG. 6 at another angle;

FIG. 8 is a schematic structural diagram of a sheath according to an embodiment of the present application;

FIG. 9 is a schematic view of a recoverable sheath assembly according to an embodiment of the present application;

FIG. 10 is a cross-sectional view of a retrievable sheath assembly according to an embodiment of the present application;

fig. 11 is a schematic view of the interventional instrument of fig. 10 after loading;

FIG. 12 is a schematic view of the interventional instrument of FIG. 11 in a semi-released configuration;

FIG. 13 is a schematic illustration of the interventional instrument of FIG. 11 shown fully released;

FIG. 14 is a schematic view of the axial segment-to-segment relationship of the pipe elements in one embodiment of the present application;

FIG. 15 is an illustration of components in the sheath;

FIG. 16a is a schematic view of the structure of a head-end tube;

FIG. 16b is a schematic view of a head-end tube in another embodiment in an expanded configuration;

FIG. 17 is a schematic view of a distal portion of the delivery system of the present application;

FIG. 18 is a cross-sectional view of the inner sheath;

FIG. 19 is an enlarged view of portion A of FIG. 18;

fig. 20 to 30 are schematic views of components involved in an assembling process in a sheath machining process according to an embodiment of the present application and related variations.

The reference numerals in the figures are illustrated as follows:

100. an operating handle;

200. a conduit;

300. a sheath tube; 310. a loading section; 320. a bending section; 330. a first extension section; 340. a head end tube; 341. spaced openings; 342. a developing area; 343. a first connector; 344. an expansion sheet; 345. a hollow-out area; 346. a body section; 347. a through hole; 348. a narrowed portion; 349. the proximal side of the strip-shaped hole;

350. a main body tube; 351. a second connector; 352. a closing-in part; 353. a hollow-out area; 354. a hollow-out area; 355. a guide rib;

360. an extension tube; 3601. a reinforcing rib (third reinforcing rib); 3602. a reinforcing rib (third reinforcing rib);

370. an inner sheath tube; 370A, a distal portion; 370B, a proximal portion; 3701. an inner layer of PTFE; 3702. weaving layer; 3703. a reinforcing rib (second reinforcing rib); 3704. weaving layer; 3705. an outer layer;

371. a distal end; 372. a core rod; 373. a circular table section; 374. a flared part; 375. a liner tube; 376. a cutting area; 377. fixing a sleeve;

380. wrapping a film; 381. a first connecting sleeve; 382. a head end outer sleeve; 383. a first liner sheet; 384. a second liner sheet; 385. a main body coat; 386. a second connecting sleeve; 387. connecting a sleeve;

400. a sheath-core assembly;

420. a core tube assembly; 421. a guide head; 422. a lock; 4221. a lock hole; 4222. a distributing board; 4223. a pull wire; 4224. a lock lever; 4225. threading a sleeve; 4226. a limiting groove; 423. layering; 424. an inner core; 425. a core tube; 4251. a compliant section; 4252. a second extension section; 4253. a rib (first rib);

500. an interventional instrument; 501. and (5) connecting lugs.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, in one embodiment of the present application, a retrievable sheath assembly is provided for use in a delivery system for delivering an interventional device, wherein the delivery system has opposite distal and proximal ends, and the delivery system includes a proximal operating handle 100 and a distally extending retrievable sheath assembly coupled to the operating handle 100.

The recyclable sheath assembly of the present embodiment includes a sheath 300 and a sheath core assembly 400, wherein the sheath 300 is slidably fitted to the outer circumference of the sheath core assembly 400. The sheath core assembly comprises a core tube and a locking piece fixed at the far end of the core tube and used for connecting an interventional instrument.

In other embodiments, the delivery system may further comprise a catheter 200 fixed relative to the operating handle 100, the catheter 200 being used to establish a channel to prevent injury to the body tissue as the sheath 300 reciprocates. The interventional device is loaded into the sheath core assembly 400 and is carried along with the catheter 200 into the body under the sheath 300. the sheath 300 is then axially movable relative to the other two to effect release and, if necessary, retrieval of the interventional device.

Referring to fig. 2a to 2b, the core tube assembly 420 includes a core tube 425, a locking member 422 is installed at a distal end portion of the core tube 425 for connecting an interventional instrument, and the core tube 425 may be made of a metal material such as a hypotube, and may be fixed to the locking member 422 by welding, bonding, or fastening.

The distal end of core tube 425 further extends out of locking element 422 and is secured with guide head 421. The distal end of the guide head 421 has a rounded head structure with a convergent shape to facilitate the passing and advancing in the body, and the position between the guide head 421 and the locking element 422 is used as the loading position of the interventional device, and the interventional device in a compressed state is in the position and is in limit fit with the locking element 422.

In one embodiment, inner core 424 is threaded into barrel 425, the distal end of inner core 424 extends out of locking element 422 and is fixed with guide head 421, the extension length of the proximal end of inner core 424 is not limited strictly, the position at the periphery of inner core and between guide head and locking element is used as the loading position of the interventional device, the interventional device in the compressed state is in the position and is in limit fit with locking element 422, and the radial space of the loading position is expanded because inner core 424 has a smaller outer diameter relative to barrel 425 because barrel 425 does not extend to the loading position.

Referring to fig. 3 a-3 b, the locking element may have a variety of different configurations, such as a groove configuration for engaging with an engaging ear on the stent, a radially outwardly projecting protrusion configuration, or a wire-by-wire configuration, wherein a long wire or wire loop is engaged with the stent, regardless of the configuration, for engaging with the engaging ear of the stent.

In some embodiments, the locking element 422 may be provided with 1 or more retaining grooves 4226 around the circumference of the interventional device with engaging ears 501 received therein, the retaining grooves 4226 being configured to provide axial retention of the interventional device and only allow release of the interventional device upon radial expansion. In order to prevent the connecting lug from accidentally falling out or suddenly bending outwards to stab tissues when the connecting lug is released, pressing strips 423 matched with the limiting grooves 4226 are further fixed at the locking piece 422, the connecting lug is limited in the limiting grooves 4226 by the constraint of the sheath tube after the connecting lug is loaded, the safety is further improved, and the flexible pressing strips 423 are outwards turned outwards to allow the connecting lug to fall out of the locking piece 422 when the connecting lug is released.

Inner core 424 and core tube 425, both of tubular construction, do not require axial relative movement between core tube 425 and inner core 424, and therefore are nested and welded to one another, and may be provided with one or more weld attachment points. If necessary, a bush may be added to the welding portion to fill the radial gap between the core tube 425 and the inner core 424, and the inner core tube 425 and the bush may be welded to each other.

The plunger 425 is secured directly or indirectly to the proximal side of the locking element 422 at one end and extends toward the operating handle at the other end.

In one embodiment, to facilitate bending to change the distal orientation, the barrel 425 includes a compliant segment 4251 adjacent the locking element 422, and a second extension segment 4252 abutting and extending proximally from the compliant segment 4251.

In one embodiment, compliant segment 4251 is a hypotube having a length in the range of 120mm to 180mm, such as 150 mm.

The second extension 4252 is made of a steel cable pipe (woven or twisted by metal wires); in other embodiments, core tube 425 is a full piece of hypotube. The hypotube can ensure axial supporting force and can be bent radially, in order to control the bending direction of the compliant section 4251, the compliant section 4251 can be provided with a reinforcing rib extending axially, the reinforcing rib is obtained by cutting the corresponding part of the hypotube (the reinforcing rib is formed in an area which is not cut or has relatively sparse cutting marks), and when the core tube 425 is a whole hypotube, the reinforcing rib can correspondingly extend to the near end.

Referring to fig. 4 and 5, in some embodiments, the locking element is in a wire-controlled manner, the interventional instrument 500 has a coupling ear 501 at a proximal end thereof, the coupling ear 501 generally has a hole or hook for threading a pull wire 4223, the locking element 422 has a locking hole 4221, the locking rod 4224 is engaged with the locking hole 4221 at a distal end thereof, and the proximal end thereof can extend to the operating handle.

In a loading state, the pull wire 4223 passes through the connecting lug 501 and then is sleeved on the lock rod 4224, the far end of the lock rod 4224 is inserted into the lock hole 4221, so that the pull wire 4223 can limit the connecting lug 501 from coming out of the lock piece 422, when release is needed, the lock rod 4224 is pulled towards the near end and comes out of the lock hole 4221, the pull wire 4223 is also released, and the connecting lug 501 is allowed to come out of the lock piece 422.

The number of the connecting lugs 501 is multiple, and a plurality of pull wires 4223 are arranged, each pull wire 4223 extends towards the far end through a wire distributing disc 4222, and a wire threading sleeve 4225 is sleeved on the periphery of the core tube 425 for arranging the wire harness so as to form an extending channel of the pull wire 4223.

The locking rods 4224 and the locking holes 4221 are used as a set of locking mechanism, and multiple sets of locking mechanisms can be arranged as required and are sequentially arranged along the circumferential direction of the locking piece 422.

Referring to fig. 6, fig. 7, when the compliant segment 4251 is cut, the cutting slit width (i.e., laser spot diameter): 0.1-1 mm, seam spacing: 0.1-1 mm; wherein an uncut portion extends in the axial direction to form a rib 4253.

Referring to fig. 8 to 9, in order to adapt to bending or to adaptively change the distal direction during passing through the body, the sheath 300 at the outermost layer has correspondingly different stiffness distributions at different axial positions, and the sheath 300 sequentially includes a loading section 310, a bending section 320 and a first extending section 330 from the distal end to the proximal end. In use, primarily bends proximal to the loading region that receives the interventional instrument 500, i.e., where the bending section 320 is located.

Referring to fig. 10 to 17, in an embodiment, a nesting relationship between the sheath 300 and the core tube assembly 420 and a releasing process of the interventional instrument are illustrated, in which the sheath 300 is also illustrated, and a general axial position relationship between the segments in the core tube assembly 420 is also illustrated, for each segment, the sheath 300 adopts a multi-layer composite structure, that is, for a certain segment, the multi-layer structure is adopted and different components are included in processing, and the structure and the process of the sheath 300 are also one of the improvements of the present application. In this embodiment, core tube assembly 420 includes a core tube 425 having a locking element 422 secured to core tube 425, and a distal end of core tube 425 further extends beyond locking element 422 and has a guide head 421 secured at a distal end. The distal end of the guide head 421 has a rounded head structure with a convergent shape to facilitate the passing and advancing in the body, and the position between the guide head 421 and the locking element 422 is used as the loading position of the interventional device, and the interventional device in a compressed state is in the position and is in limit fit with the locking element 422.

In one embodiment, core tube 425 has core 424 threaded therein, the distal end of core 424 extends out of locking element 422 and is fixed with guide head 421, the distal end of core tube 425 extends only to locking element 422, the proximal extension of core 424 is not limited, and core 424 has a smaller outer diameter relative to core tube 425 because core tube 425 does not extend to the loading position, so that the radial space of the loading position can be expanded.

With reference to the above embodiments, in an embodiment of the present application, the sheath is divided into a loading section 310, a bending section 320, and a first extending section 330 sequentially from a distal end to a proximal end in an axial direction, wherein the loading section 310 is used for receiving the interventional instrument 500, and the sheath adopts a multi-layer structure, including:

the inner sheath tubes 370, the inner sheath tubes 370 are distributed on the bending section and the first extending section in the axial direction;

an inner lining tube 375, wherein the inner lining tube 375 is butted against the distal end of the inner sheath tube 370, and the inner lining tube 375 is distributed on the loading section in the axial direction;

the metal pipe wraps the distal end part of the inner sheath pipe and the periphery of the inner lining pipe, and is distributed on the bending section and the loading section in the axial direction;

and the outer wrapping film 380 wraps the periphery of the metal pipe, and the outer wrapping film 380 is distributed on the bending section and the loading section in the axial direction.

Fig. 15 illustrates a part of the visible components of the sheath 300, the distal portion of the sheath 300 generally has at least three layers, the inner layer and the outer layer are made of polymer materials, the middle layer is made of metal tube, the middle layer adopts three-segment butt joint structure, and comprises a head end tube 340, a main tube 350 and an extension tube 360 which are butt jointed in sequence from the distal end to the proximal end, wherein the head end tube and the main tube are distributed on the loading section, and the extension tube is distributed on the bending section in the axial direction.

The bending section can be bent to change the pointing direction of the distal end of the sheath tube during the delivery process, and the first extension section mainly provides enough axial pushing force and pulling force and has enough length to be connected with an operating handle.

The head-end tube 340 is formed by cutting a nickel-titanium alloy tube, and the main tube 350 and the extension tube 360 are respectively formed by cutting stainless steel tubes. The head end tube 340 and the main tube 350 have larger tube diameters relative to the extension tube 360 due to the fact that the interventional device is wrapped, and the joint position of the main tube 350 and the extension tube 360 is correspondingly flared and tapered in combination with the axial position relation of fig. 14.

Referring to fig. 16a, in an embodiment, a plurality of spaced openings 341 are formed at a distal end side of the head end tube 340 along a circumferential direction, an expansion piece 344 is disposed between two adjacent spaced openings, and each expansion piece 344 is provided with a hollow area 345. In a preferred embodiment, the expansion pieces 344 are uniformly arranged along the circumferential direction, and the number of the expansion pieces is 3-6, for example 5.

In general, the head pipe 340 preferably adopts an integral structure, the body section 346 forms a developing area 342 in a hollow manner for installing a developing point, and the first connector 343 is T-shaped for abutting against the main pipe 350 and axially limiting. The through holes 347 are distributed in both the main body segment 346 and the first connecting member 343, so that the polymer materials as the inner and outer layers of the sheath tube can be fused better.

The spacing opening 341 is a strip-shaped gap, the distal end is open and the proximal end is closed, because the head-end tube 340 is made of elastic metal material such as nickel-titanium alloy, the expansion pieces 344 can be radially outwards turned, the interventional device can adapt to gradual deformation when the interventional device is released, the interventional device is prevented from suddenly collapsing at the final stage of release, and when the interventional device needs to be retracted, the expansion pieces 344 are radially outwards turned to form a horn mouth, so that the interventional device can be guided to be gradually radially compressed and accommodated in the sheath tube 300.

The hollow-out areas 345 of the expansion pieces 344 facilitate deformation of the expansion pieces and reduce eversion resistance, and in one embodiment, the hollow-out areas 345 are strip-shaped holes extending in the axial direction of the head end pipe 340, and one, two or more strip-shaped holes are formed in the same expansion piece.

In a preferred embodiment, the strip-shaped apertures extend equally wide. The two ends of the strip-shaped hole in the length direction are arc-shaped inner edges. Can avoid the cracking caused by over concentration of stress during deformation.

In one embodiment, each expansion tab 344 has a narrowed portion 348 at a proximal portion and the spaced openings have corresponding widened portions at a proximal portion that correspond to the narrowed portion 348.

To distribute the stress, the inner edge of the widened portion adopts a smooth curve, such as a large head portion in the shape of a drop.

In one embodiment, the spacer openings themselves extend generally of equal width except for the distal side chamfered to accommodate the expansion tabs, and the widened portion of the proximal side.

The width of the equally wide extending portion of the slit is substantially the same as the width of the slit, and for example, the width of the slit is ± 20% of the reference width, based on the width of the slit.

To facilitate eversion of each expansion tab 344 at the constriction 348 and reduce resistance to deformation at the proximal side of the constriction, in one embodiment, the proximal side 349 of the slot passes over the constriction of the expansion tab. In a preferred embodiment, the proximal side 349 of the strip-shaped hole crosses over the narrowed portion of the expansion piece by 1-5 mm, for example, 1.5-3 mm.

To avoid safety concerns, in one embodiment, the distal end of the expansion tab has a smooth outer edge, for example, rounded or generally rounded in shape projecting distally.

Referring to fig. 16b, in an embodiment, each expansion piece 344 is provided with a hollow area 345, the hollow area 345 is a plurality of through holes arranged at intervals along the axial direction of the sheath, and the total area of the through holes on each expansion piece is less than 50% of the area of the expansion piece. It can be seen that the area of the through hole is larger the closer to the distal end on the same expansion sheet. The through holes are circular or oval, and the number of the through holes on the same expansion piece is 2-5.

Like the previous embodiment, the body section 346 of the head end tube forms a developing area 342 in a hollow manner for installing a developing point, and the first connector 343 is T-shaped for abutting against the main tube and axially limiting. The through holes 347 are distributed on both the main body 346 and the first connecting head 343, so that the polymer materials of the inner and outer layers of the sheath tube can be fused better. The spacing openings 341 are formed between the adjacent expansion pieces 344, the spacing openings 341 are strip-shaped gaps, the far ends of the spacing openings are open, the near ends of the spacing openings are closed, the expansion pieces 344 are more narrow towards the far ends, and the arc-shaped edges are arranged at the farthest end parts to improve the safety.

For preventing the metal material scratch vascular wall in intermediate level, the outmost at least parcel head end pipe 340 of sheath pipe, main part pipe 350 and extension pipe 360, outmost outer involucrum 380 can adopt macromolecular material, because the metal material part is the multistage structure, outer involucrum 380 also adopts multistage mosaic structure and then melts into an organic whole man-hour adding.

The inner layer of the sheath comprises an inner sheath tube 370 and an inner lining tube 375, wherein the inner sheath tube 370 extends proximally from one side and extends to the joint of the main tube 350 and the extension tube 360, the inner sheath tube 370 extends distally from the joint of the main tube 350 and the extension tube 360 through the inner lining tube 375 to the distal side of the head tube 340, and the inner lining tube 375 may be made of PTFE.

Axially along the inner sheath tube, the inner sheath tube comprises a distal portion 370A in the flexed section, and a proximal portion 370B in the first extended section, wherein the distal portion 370A is less rigid, i.e. more compliant, than said proximal portion 370B.

The extension tube 360 may also be cut to form a stiffener.

Referring to fig. 18 to 19, the inner sheath tube 370 itself has a multilayer structure, which includes, from the inside to the outside, an inner layer 3701 of PTFE, a woven layer 3702, a woven layer 3704, and an outer layer 3705, wherein two reinforcing ribs 3703 (second reinforcing ribs) extending in the axial direction are fixedly wrapped between the woven layer 3702 and the woven layer 3704.

One of the two ribs 3703 is at the same circumferential position as rib 4253 in compliant section 4251 and the other is 180 degrees different from rib 4253. Braided layers 3702 and 3704 do not require significant layering, can be integrally braided and hold the reinforcing ribs, and outer layer 3705 can be made of Pebax.

The extension pipe 360 can be provided with a reinforcing rib 3601, and the reinforcing rib 3601 and the reinforcing rib 4253 are positioned on the same radial side, namely the same circumferential position;

or in other embodiments, two reinforcing ribs are arranged in the extension pipe 360, which are respectively a reinforcing rib 3601 and a reinforcing rib 3602, wherein the reinforcing rib 3601 and the reinforcing rib 4253 are located on the same radial side, i.e. at the same circumferential position, and the circumferential positions of the reinforcing rib 3602 and the reinforcing rib 4253 are 180 degrees different.

The inner sheath 370 is both in the bending section 320 and the first extension section 330, and because the bending section 320 has a larger bending angle during bending, the strength of the inner sheath 370 is different between the bending section 320 and the first extension section 330, and the inner sheath 370 is softer in the bending section 320, for example, the inner sheath 370 adopts 30-59D Pebax for the outer layer 3705 of the bending section 320, 60-90D Pebax for the outer layer 3705 of the first extension section 330, and the same arrangement can be adopted for the braided layer and the PTFE inner layer 3701 at different positions of the inner sheath 370.

Referring to fig. 20 to 30, in an embodiment of the present application, a method for processing a recyclable sheath assembly is provided, wherein the sheath assembly can be processed by a conventional method in addition to the embodiments of the present application, and the processing process of the sheath 300 includes:

step S100, processing the distal end of the inner sheath tube to form a flaring part;

the end portion of the inner sheath, i.e., the distal end 371, may be heat softened and the distal end 371 may be expanded to form an expanded portion 374 in conjunction with an inserted core rod 372, and a portion of the outer circumference of the core rod 372 may be formed into a round land 373 in accordance with the desired shape of the expanded portion 374. Step S200, fixedly sleeving a lining pipe on the periphery of the flaring part;

taking an inner lining pipe 375 made of PTFE material, wherein the end part of the inner lining pipe 375 is provided with lugs arranged at intervals along the circumferential direction, a cutting area 376 is arranged between the lugs, the end is wrapped at an expanding part 374, and then the end is wrapped by a fixing sleeve 377 to be hot-melted, namely the inner lining pipe 375 is connected to the far end 371 of an inner sheath pipe.

The fixing sleeve 377 and the flared portion 374 are made of the same material, such as Pebax, and the cutting area 376 facilitates the fusion of the fixing sleeve 377 and the flared portion 374, so that the connection strength of the lining tube 375 is guaranteed.

Step S300, sleeving a metal pipe on the peripheries of the inner sheath pipe and the inner lining pipe;

the extension pipe 360, the main body pipe 350 and the head end pipe 340 are sequentially butted, the adjacent two are axially limited by adopting modes such as hooks, buckles and the like, wherein the head end pipe 340 adopts a nickel-titanium alloy pipe, and the extension pipe 360 and the main body pipe 350 can adopt stainless steel pipe materials.

The proximal side of the head tube 340 is provided with a first connector 343 in the shape of a T, the distal side of the main tube 350 is provided with a second connector 351 in the shape of a T, and the first connector 343 and the second connector 351 are mutually matched in a complementary manner for axial limitation.

The proximal side of the main tube 350 has a mouth portion 352 and is adapted to engage the extension tube 360 through the mouth portion 352, which may be in the form of a conventional hook or snap. The main tube 350 has hollow areas 353 and 354 distributed on the wall thereof, and guide ribs 355 extending axially are distributed between the hollow areas 353 and 354, the guide ribs 355 can limit the bending direction of the sheath tube 300, and the two guide ribs 355 are arranged oppositely in the radial direction.

The extension tube 360, the main tube 350 and the head end tube 340 are sequentially butted and then sleeved outside the inner sheath tube 370 and the inner lining tube 375, the position of the flared part 374 corresponds to the axial position of the closed part 352, the inner lining tube 375 is slightly longer than the head end tube 340, and the part of the inner lining tube 375 corresponding to the spaced opening 341 is correspondingly cut to adapt to the deformation of the expansion piece.

And S400, coating the outer surface of the metal pipe by sections by using an outer coating material, and forming an outer coating film integrally after the outer coating material of each section is hot-melted.

The method specifically comprises the following steps:

step S410, wrapping a first connecting sleeve 381 at the butt joint part of the main body pipe 350 and the head end pipe 340, wrapping a head end outer sleeve 382 at the periphery of the head end pipe 340, and fixing the first connecting sleeve 381 and the head end outer sleeve 382 in a hot melting mode;

the head end outer sleeve 382 is slightly longer than the head end pipe 340 to be approximately aligned with the inner lining pipe 375, and then the first connecting sleeve 381 and the head end outer sleeve 382 are hot-melted together with the corresponding position of the inner lining pipe 375 to wrap and fix the butt joint part of the main body pipe 350 and the head end pipe 340 and the inside and outside of the head end pipe 340.

The first lining 383 and the second lining 384 are placed in the hollowed-out areas 353 and 354, and then the first lining 383 and the second lining 384 are hot-melted with the corresponding positions of the lining tube 375, and the first lining 383 and the second lining 384 penetrate into and fill the corresponding hollowed-out areas.

Step S420, wrapping the main body outer sleeve 385 on the periphery of the main body pipe 350 and performing hot melting and fixing;

the distal side of the body sleeve 385 is generally aligned with the proximal side of the first coupling sleeve 381, and the proximal side of the body sleeve 385 surrounds the interface of the elongated tube 360 and the body tube 350.

The head end outer cover 382 is required to be more flexible, the material can be TPU, etc., and the first connecting cover 381, the first lining 383, the second lining 384 and the main body outer cover 385 can be Pebax, etc., which has better strength, wherein the first lining 383 and the second lining 384 can be thinner than the main body outer cover 385, for example, the thickness of the first lining 383 and the second lining 384 is about 0.15mm, and the thickness of the main body outer cover 385 can be increased to 0.35 mm.

In addition, the first connecting sleeve 381 requires a greater strength, so that a relatively hard material can be selected, for example, the hardness is 60-72D, and the main body cover 385 mainly covers the protection function, and the hardness can be reduced by a suitable amount, for example, 40-55D.

Step S430, wrapping a second connecting sleeve 386 at the proximal end of the extension tube 360 and the inner sheath tube 370 at the adjacent position, and fixing the second connecting sleeve 386 by hot melting;

step S440, the extension tube 360 is wrapped with the connection sleeve 387 and fixed by heat fusion.

The axial position of the connecting sleeve 387 is such that the proximal end abuts the second connecting sleeve 386 and the distal end abuts the body sleeve 385.

The second connecting sleeve 386 adopts Pebax and the like with better strength. The connecting sleeve 387 is required to be flexible and better at the bending part, the material can be TPU (thermoplastic polyurethane), and the like, and in addition, the connecting sleeve 387 can also prevent the internal metal pipe from directly contacting and scratching the blood vessel and also has the sealing effect

The material of each section of parcel in extension pipe 360, main part pipe 350, head end pipe 340 three periphery finally melts and forms outer envelope 380 as an organic whole, and the part hot melt binding off that surpasss at the head end pipe 340 distal end is finally handled, and wherein also can corresponding cutting with the position that the interval opening 341 corresponds to the adaptation is possibly out of shape at interval opening 341, or utilizes the material elasticity adaptation of head end overcoat 382 self.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features. When technical features in different embodiments are represented in the same drawing, it can be seen that the drawing also discloses a combination of the embodiments concerned.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application.

Claims (20)

1. A recoverable sheath tube component comprises a sheath tube and a sheath core component which are matched in a sliding and nesting mode, wherein the sheath core component comprises a core tube, a locking piece used for connecting an interventional instrument is installed at the far-end part of the core tube, the sheath tube is arranged at the periphery of the sheath core component,

the core tube including a compliant segment adjacent the locking element and a second extension segment abutting the compliant segment and extending proximally, the compliant segment having a lesser stiffness than the second extension segment;

sheath pipe is divided into loading section, suitable curved section and first extension section by distal end to near-end in proper order in the axial, wherein the loading section is used for accomodating intervention apparatus, the sheath pipe adopts multilayer structure, includes:

the inner sheath pipe is distributed on the bending section and the first extending section in the axial direction;

the lining pipe is butted at the far end of the inner sheath pipe and is distributed on the loading section in the axial direction;

the metal pipe wraps the distal end part of the inner sheath pipe and the periphery of the inner lining pipe, and is distributed on the bending section and the loading section in the axial direction;

the outer wrapping film is wrapped on the periphery of the metal pipe and is distributed on the bending section and the loading section in the axial direction.

2. The retrievable sheath assembly of claim 1, wherein the locking element has a retaining groove on an outer circumference thereof for receiving an interventional device, the proximal portion of the interventional device being received in the retaining groove in the stowed position and being axially constrained by the retaining groove.

3. The retrievable sheath assembly of claim 2, wherein the locking member has a bead fixed to an outer periphery thereof for engaging with each of the retaining grooves, the bead being constrained by the sheath to retain a proximal portion of the interventional device within the retaining grooves.

4. The recyclable sheath assembly of claim 3, wherein the bead is a flexible material.

5. The retrievable sheath assembly of claim 1, wherein the metal tube comprises, from the distal end to the proximal end, a head end tube, a main tube, and an extension tube, which are sequentially butted, wherein the head end tube and the main tube are distributed in the loading section, and the extension tube is distributed in the bending section.

6. The retrievable sheath assembly of claim 5, wherein the head end tube includes a body section, 3-6 expansion tabs circumferentially spaced apart on a distal side of the body section, a first connector on a proximal side of the body section, the distal side of the body tube carrying a second connector, the first and second connectors being interfitting and complementary in shape.

7. The recoverable sheath assembly of claim 6, wherein each expansion tab comprises a plurality of through holes spaced axially along the sheath, and wherein the total area of the through holes of each expansion tab is less than 50% of the area of the expansion tab.

8. The retrievable sheath assembly of claim 7, wherein the through holes are circular or oval and the number of through holes on the same expansion plate is 2 to 5.

9. The recoverable sheath assembly of claim 5, wherein each expansion tab comprises a hollow, the hollow being a strip-shaped hole extending axially along the head tube.

10. The retrievable sheath assembly of claim 9, wherein a space is provided between adjacent ones of the expansion tabs, each expansion tab having a narrowed portion at a proximal end portion, the space having a widened portion at a proximal end portion corresponding to the narrowed portion.

11. The retrievable sheath assembly of claim 10, wherein the proximal side of the slotted aperture passes over a narrowing of the expansion tab.

12. The retrievable sheath assembly of claim 1, wherein the core tube extends distally out of the locking element and has a guide head secured to a distal-most end of the extension, a loading position between the guide head and the locking element, and a compressed access device in the loading position and coupled to the locking element.

13. The retrievable sheath assembly of claim 12, wherein an inner core is threaded through the core tube, a distal end of the inner core extends out of the locking element and is secured to the guide head, and the inner core is secured relative to the core tube.

14. The retrievable sheath assembly of claim 1, wherein the core tube is a full length hypotube;

or the compliant section adopts a hypotube, and the second extension section adopts a steel cable tube made of metal wires.

15. The retrievable sheath assembly of claim 1, wherein the compliant segment has a length of 120mm to 180 mm; the compliant section has a first rib extending in an axial direction.

16. The recyclable sheath assembly of claim 15, wherein the inner sheath has a multi-layer structure, and two second reinforcing ribs extending in the axial direction are provided in the sandwich layer, wherein one of the second reinforcing ribs is located at the same circumferential position as the first reinforcing rib, and the other second reinforcing rib is located at a position different from the circumferential position of the first reinforcing rib by 180 degrees.

17. The retrievable sheath assembly of claim 16, wherein the inner sheath is an inner layer, a braided layer, and an outer layer in order from the inside out, and wherein the second reinforcing ribs are within the braided layer.

18. The retrievable sheath assembly of claim 5, wherein the core tube includes a compliant segment adjacent the locking element, and a second extension segment abutting the compliant segment and extending proximally; the compliant section is provided with a first reinforcing rib extending along the axial direction;

a third reinforcing rib extending along the axial direction is arranged in the extension pipe, and the third reinforcing rib is one and is positioned at the same circumferential position as the first reinforcing rib; or two third reinforcing ribs are arranged, one third reinforcing rib is located at the same circumferential position as the first reinforcing rib, and the other third reinforcing rib is 180 degrees different from the first reinforcing rib in circumferential position.

19. A processing method of a recyclable sheath tube assembly is characterized by comprising the steps of respectively providing a sheath tube core assembly and a sheath tube and assembling, wherein the processing method of the sheath tube comprises the following steps:

step S100, providing an inner sheath tube and processing the distal end of the inner sheath tube to form a flaring part;

step S200, fixedly sleeving a lining pipe on the periphery of the flaring part;

step S300, sleeving a metal pipe on the periphery of the distal end part of the inner sheath pipe and the periphery of the lining pipe;

and S400, coating the outer surface of the metal pipe by sections by using an outer coating material, and forming an outer coating film integrally after the outer coating material of each section is hot-melted.

20. The method of processing a recyclable sheath assembly as described in claim 19, wherein the recyclable sheath assembly is the recyclable sheath assembly as described in any one of claims 1 to 18.

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