EXPANDABLE SLEEVE AND COATING FOR IT

Abstract

An expandable sleeve body for a sleeve assembly. The sleeve body has a tubular frame with a lumen within it. The frame contains cavities. The frame is expandable to a larger diameter and contractible to a smaller diameter, and is also flexible. The sleeve body has an inner coating formed over an area of ​​the lumen defined by the tubular frame, and an outer coating formed over an outer surface of the frame. The inner coating and an inner layer of a multilayer outer coating can be made of expanded polytetrafluoroethylene (ETFE). The expanded ETFE can be impregnated with silicone oil to increase lubricity.

Description

REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 341,252, filed May 12, 2022, the disclosure of which is incorporated by reference into this application. BACKGROUND

[0002] Intracardiac heart pumps can be inserted into the heart either surgically or percutaneously and used to pump blood from one location in the heart or circulatory system to another location in the heart or circulatory system. For example, when placed within the heart, an intracardiac pump can pump blood from the left ventricle into the aorta or pump blood from the inferior vena cava into the pulmonary artery. Intracardiac pumps can be powered by a motor external to the patient's body (and its associated drive cable) or by an integrated motor within the patient's body. Some intracardiac blood pump systems can operate in parallel with the patient's own heart to supplement cardiac output and partially or completely offload the heart's components. Examples of such systems include the IMPELLA® family of devices (Abiomed, Inc., Danvers, Mass.).

[0003] A common approach involves delivering an intracardiac blood pump through a catheterization procedure via the femoral artery using a detachable introducer sheath. The sheath can alternatively be inserted into other locations, such as the femoral vein or another pathway for delivering a pump to assist the left or right side of the heart.

[0004] The introducer sheath can be inserted through an arteriotomy into the femoral artery to create an introduction path for the pump assembly. A portion of the pump assembly is then advanced into the artery through an inner lumen of the introducer sheath. The required size of the arteriotomy is of great interest. Accordingly, expandable introducer sheaths have been developed, requiring a smaller arteriotomy opening to accommodate the sheath and the medical device passed through it. Accordingly, improvements in expandable introducer sheaths continue to be sought. SHORT SUMMARY

[0005] In some aspects, an expandable introducer sheath includes a coating positioned within the sheath, and the coating may be constructed and arranged to reduce friction when a medical device is advanced through the sheath. The reduced friction makes it easier to advance the medical device through the sheath, and this ease of movement is utilized to provide a sheath with an at least nominally smaller diameter that requires an at least nominally smaller arteriotomy opening through which the sheath is advanced into the patient. "Diameter," as used herein, is used to describe a distance from one side of the introducer sheath or medical device to the other side. The diameter is not intended to imply that the introducer sheath or the lumen of the introducer sheath or the cross-sections of the device are precisely circular.In some embodiments, the coating is formed from polytetrafluoroethylene (ePTFE).

[0006] Described herein is an introducer sheath assembly comprising a tubular frame having a lumen therein, the tubular frame configured to temporarily expand from a first diameter to a second, larger diameter when a portion of a medical device having a diameter greater than the first diameter passes through the tubular frame. The introducer sheath assembly further comprises a coating adjacent to an inner surface of the tubular frame, the coating formed from expanded polytetrafluoroethylene (ePTFE), and a fitting connected to a proximal end of the tubular frame, the fitting including a hemostasis valve.

[0007] In one aspect, the ePTFE coating is applied to the inner surface of the tubular frame. In another aspect, a primer is formed between the ePTFE coating and an inner surface of the lumen defined by the tubular frame. In another aspect, the introducer sheath assembly includes an outer coating formed on an outer surface of the tubular frame. The tubular frame may be made of a braided nitinol tube or a laser-machined hypotube.

[0008] In one aspect, the outer coating is made of thermoplastic polyurethane or expanded polytetrafluoroethylene. The outer coating may be single-layer or multi-layer. In one aspect, the outer coating consists of two layers. A first layer may be formed over the outer surface of the frame, and the first layer may be made of a thermoplastic polyurethane. A second layer of the two layers of the outer coating is formed over the first layer, and the second layer may be made of polytetrafluoroethylene.

[0009] An expandable sleeve body is also disclosed. The expandable sleeve body has a tubular frame with a lumen therein, the frame having spaces therebetween, the frame being expandable to a larger diameter and contractable to a smaller diameter, and also being flexible. The expandable sleeve body has an inner coating formed over a surface of the lumen defined by the tubular frame and an outer coating formed over an outer surface of the frame. In one aspect, a primer is formed between the inner coating and the surface of the lumen defined by the tubular frame. In another aspect, the primer is formed between the outer coating and the outer surface of the frame.

[0010] In another aspect, the frame can be made from either a braided nitinol tube or a laser-machined hypotube. In another aspect, the inner coating can be made from expanded polytetrafluoroethylene. In another aspect, the expandable sleeve can have an outer coating made from thermoplastic polyurethane or expanded polytetrafluoroethylene and can be multi-layered. When the outer coating of the expandable sleeve is multi-layered, in one aspect, the multi-layer outer coating can have two layers, wherein a first layer is formed over the outer surface of the frame, and wherein the first layer comprises thermoplastic polyurethane. A second layer of the two layers of the outer coating is formed over the first layer, wherein the second layer comprises expanded polytetrafluoroethylene. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a sleeve arrangement. Fig. Figure 2 shows a first sleeve body configured to be used in a sleeve assembly such as that shown in Fig. 1 can be used. Fig. 3 is a cross-sectional view of the sleeve body of Fig. 2, taken along the AA axis. Fig. Figure 4 is a schematic representation of the side wall portion A of the sleeve body of Fig. 3. F Fig. Figure 5 illustrates a second sleeve body suitable for use in a sleeve assembly such as that shown in Fig. 1 is configured. Fig. 6 is a cross-sectional view of the sleeve body of Fig. 5, which was taken via the BB axis. Fig. Figure 7 is a schematic representation of the side wall portion B of the sleeve body of Fig. 6. Fig. Figure 8 shows a third sleeve body suitable for use in a sleeve assembly such as that shown in Fig. 1 is configured. Fig. 9 is a cross-sectional view of the sleeve body of Fig. 8, taken along the CC axis. Fig. Figure 10 is a schematic representation of the side wall portion C of the sleeve body of Fig. 9. DETAILED DESCRIPTION

[0011] Aspects of the present disclosure are described in detail with reference to the figures, where like reference numerals indicate similar or identical elements. It should be understood that the disclosed aspects are merely examples of the disclosure that may be embodied in various forms. Well-known functions or constructions are not described in detail in order not to obscure the present disclosure with unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously apply the present disclosure in virtually any reasonably detailed structure.

[0012] To provide a comprehensive understanding of the systems, methods, and devices described herein, certain illustrative embodiments are described. Although the device and its features described herein are specifically described for use in conjunction with an intracardiac heart pump system, it is understood that all of the components and other features described below may be combined in any suitable manner and adapted and applied to other types of medical devices, such as:Electrophysiological and catheter ablation devices, angioplasty and stenting devices, angiography catheters, peripherally inserted central catheters, central venous catheters, midline catheters, peripheral catheters, inferior internal vena cava filters, abdominal aortic aneurysm treatment devices, thrombectomy devices, TAVR delivery systems, cardiac therapy and ventricular assist devices, including balloon pumps, ventricular assist devices implanted through a surgical incision, and any other venous or arterial catheters and devices.

[0013] Because commercially available introducer sheaths are generally not radially expandable, the inner diameter of the introducer sheath must always be large enough to accommodate the largest diameter part of the pump assembly, such as the pump head, even if other parts of the pump assembly, such as the catheter, have a significantly smaller diameter. In this example, the introducer requires a relatively large blood vessel opening (e.g., an arteriotomy) to insert the pump catheter through the introducer sheath into the blood vessel, which can complicate closure of the arteriotomy at the end of the procedure.

[0014] Some medical introducers for applications other than heart pump insertion have expandable sleeve bodies that can expand to allow the passage of larger diameter percutaneous devices through smaller diameter lumens into the patient's vasculature. Typically, these introducers have an inner diameter smaller than the outer diameter of the device being inserted after insertion. The introducers expand to allow the device to pass through the introducer sheath and into the vasculature and can then contract back to their smaller diameter after the larger diameter device has passed through. According to the current state of the art, these expandable introducers require a special expandable feature, such as a longitudinal fold or tear, or a lumen for fluid injection (e.g.,Saline solution) to transition from a compressed state to an expanded state. Therefore, such commercially available expandable sheaths are typically completely flexible and therefore lack rigidity within their structure, leading to kinking or buckling during insertion or withdrawal of a percutaneous medical device. Although expandable sheaths offer many advantages, improvements in design and performance are still being sought.

[0015] The systems, methods, and devices described herein provide an expandable sleeve body configured for use in an expandable sleeve assembly for introducing a medical device (e.g., an intracardiac heart pump) into a blood vessel through a vascular opening. The inventors have recognized and appreciated that expandable sleeve systems can provide numerous advantages compared to conventional non-expandable sleeves. For example, by allowing for temporary expansion during insertion of the medical device, an expandable sleeve can allow for a smaller blood vessel opening size (i.e., arteriotome size) for delivery of the medical device than a non-expandable sleeve, which must have an inner diameter at least as large as the largest diameter of the medical device to be delivered through it.However, the inventors further recognized that reducing the lumen cross-section of an expandable sheath (e.g., to a nominal or resting cross-section smaller than the portion of the largest diameter of a medical device passed therethrough) may make passage of the medical device through the introducer sheath more difficult during insertion and / or removal of the medical device. Accordingly, the systems, methods, and devices described herein provide expandable sheath systems with reduced insertion and / or removal forces, enabling further reduced sheath diameters and correspondingly smaller blood vessel opening sizes.

[0016] The expandable sleeve body described herein can be used in an expandable sleeve assembly that includes a dilator assembly. As described, the expandable sleeve body has an inner surface and an outer surface, the inner surface defining a lumen extending between the proximal and distal ends of the sleeve body. Optionally, the expandable sleeve assembly can include a hemostasis probe in addition to the expandable sleeve body. Expandable sleeve assemblies (including the expandable sleeve body, the dilator assembly, and the optional hemostasis probe) are particularly advantageous over existing expandable sleeve assemblies for patients with coronary artery disease (CAD) and peripheral arterial disease, which are associated with calcification and torsion of the arteries and complicate the insertion of introducer sheaths and catheters.

[0017] Expandable sheath assemblies with the sheath body described here are easier to insert than conventional assemblies due to their reduced insertion profile, increased flexibility, reduced friction, and reduced risk of kinking under stress. The reduced insertion profile reduces insertion-related complications, reduces stretching and stress on the vessel opening, and reduces the risk of limb ischemia. The sheath body structure described here provides sufficient axial rigidity so that the sheath body can be advanced into a lumen (e.g., a blood vessel) yet still resists kinking, while maintaining flexural flexibility and kink resistance and reducing frictional force to prevent "pinch fingers."Furthermore, the sleeve body structures described herein represent an improvement over existing introducer sheaths because they include at least one inner or outer coating, or both, each coating constructed and arranged to reduce the force required to expand the sleeve body (as compared to the force required to expand a sleeve having a coating without preload) and, in the case of at least one sleeve body having the inner coating described herein, to minimize device insertion and removal forces by reducing friction between the sleeve body and the device to be inserted thereby.

[0018] The sleeve body can expand between various states to accommodate the medical device as it is passed through the sleeve. For example, the sleeve body can be extended to a first, smaller diameter state (typically using a dilator) for insertion and relaxed at a desired location to a second, larger diameter to allow passage of a portion of a medical device through the lumen, wherein the portion of the medical device has a cross-sectional area larger than a cross-sectional area of ​​the lumen in the first state. In various configurations, the diameter of the sleeve body is expanded between a resting state when the sleeve is deployed to its desired location and a larger diameter state as the medical device is passed through the sleeve body.After the medical device passes through the sheath, the sheath can contract or otherwise relax, returning to its resting, smaller-diameter state. In any configuration, the expandable sheath assemblies with the sheath body described here require no additional elements compared to a standard introducer sheath assembly. That is, the assemblies described here do not have, at a minimum, i) an external balloon; ii) a fold in the expandable sheath body; and iii) a second sheath for delivery. This simplifies the use of the expandable sheath assembly (e.g., with fewer steps and less time required) with the sheath body described here.

[0019] Additionally, the instantaneous expansion of the sleeve body from the elongated state to the relaxed state (or from the relaxed state to the expanded state) reduces the size of the opening, such as an arteriotomy, required when inserting the sleeve into the patient's vasculature. Minimizing the time the sleeve body is in the expanded state also reduces damage to a vessel wall that might otherwise occur if the sleeve body is maintained in the expanded state for extended periods. Furthermore, the smaller opening required to accommodate the sleeve body in the relaxed or collapsed state reduces the risk of thrombotic occlusion of the blood vessel containing the sleeve body.

[0020] As mentioned above, the expandable sheath can deliver the sheath body into a patient's vasculature with a small profile when held under axial tension (pulled downward) prior to insertion. This has the following key advantages: i) pulling down to a small insertion profile to minimize insertion-related complications (i.e., bleeding, vessel injury, high insertion forces); and ii) maintaining a "soft" sheath body and momentary expansion for interaction at the arteriotomy site to enable small-bore closure and minimize bleeding due to minimized vessel recoil during use. It should be noted, however, that some of the sheath configurations described in the present disclosure may not be constricted prior to insertion into a vessel.For example, a sheath may be inserted and held in a relaxed state within a vessel and then briefly expanded to a larger diameter when a medical device is passed through the sheath, as described above.

[0021] Fig. 1 shows a sheath assembly 100 according to aspects of the technology disclosed herein. The sheath assembly 100 includes a hub 110 that locks the sheath in position after insertion. The hub 110 cooperates with the cap 120 to secure the sheath body 130 in position. The hub 110 also includes detents 112 (only one of which is visible) to facilitate attachment of the hub 110 to the dilator hub 230. The butterfly / suture pad 140 is configured to assist in attaching the sheath assembly 100 to the patient (e.g., by suturing the assembly to the patient). In this description, the proximal end of the assembly is at the hub / cap end, and the distal end of the assembly is at the tip end.Fluid may be introduced into the assembly via sidearm channel 160, and fluid flow into the device may be controlled by stopcock 170. A hemostasis valve (not shown) may also be included in fitting 110, with the hemostasis valve configured to prevent blood from escaping from the patient during insertion and / or removal of an intracardiac blood pump or other components. Although any suitable hemostasis valve may be used with the sleeve assembly described herein, examples are described and illustrated in U.S. Patent Application No. 17 / 097,582, filed November 13, 2020, and published May 20, 2021, as U.S. Patent Publication No. 20210146111, which is incorporated by reference herein.Additionally, in some embodiments, the connector 110 may include a foam insert (not shown) disposed proximal to the hemostasis valve, which may be impregnated with a lubricant such as silicone so that the components are lubricated as they are inserted through the foam and into the sleeve body 130.

[0022] The Fig. 2-10 show various sleeve body constructions configured for use with the sleeve assembly 100 according to aspects of the presently disclosed technology. In all aspects, the expandable sleeve body 200, 300, 400 comprises a multi-layer structure having a circumferential frame 202, 302, 402 disposed between an inner coating 204, 304, 404 and an outer coating 206, 306, 406. The frame 202, 302, 402 may be made of any suitable material. To provide an expandable frame that is sufficiently kink-resistant, the expandable frame 202, 302, 402 may be made of a braided material. Alternatively, the frame may be a hypotube in which interstices are introduced by laser cutting. Hypotubes are typically made of metal. Another aspect is that the braided material is a metal material that is both elastic and has shape memory properties.An example of a suitable braided material is a Nitinol braid. In some aspects according to the present disclosure, the frame 202, 302, 402 is an expandable braided frame composed of strands of a flexible metal such as Nitinol. The frame 202, 302, 402 may include an expansion mechanism that assists in expanding and / or contracting the frame. For example, strands of the braided frame may be configured with a bias to expand and / or contract from a rest position. According to some implementations, the expansion mechanism allows strands of the braided frame to slide relative to each other as the frame expands and contracts.

[0023] Each of the inner coatings 204, 304, 404 and outer coatings 206, 306, 406 is a low-friction layer applied to the frame 202, 302, 402 to mitigate (i.e., reduce) the forces required to insert and remove the device (e.g., an intracardiac heart pump) by reducing the frictional forces generated during insertion and removal. Additionally, the inner coating 204, 304, 404 and the outer coating 206, 306, 406 may allow the sleeve to expand with a relatively lower force compared to the force required to expand the sleeve without coatings. As shown in the Fig. As shown, the inner coating 204, 304, 404 and the outer coating 206, 306, 406 are applied (or bonded) to the inner surface 208, 308, 408 of the frame 202, 302, 402 and the outer surface 210, 310, 410 of the frame 202, 302, 402, respectively, using a thermoforming process (also known as lamination). Because the frame in these embodiments is braided, the inner and outer layers can bond together through the interstices of the braid. Therefore, the inner and outer coating materials are selected to expand and contract along with the wrapper frame.

[0024] As in the Fig. 3-4, 6-7 and 9-10, the sleeve body 200, 300, 400 may further include an inner primer 212, 312, 412 disposed between the inner surface 208, 308, 408 of the frame 202, 302, 402 and the inner coating 204, 304, 404, and an outer primer 214, 314, 414 disposed between the outer surface 210, 310, 410 of the frame 202, 302, 402 and the outer coating 206, 306, 406. The inner primer 212, 312, 412 and the outer primer 214, 314, 414 serve to improve the adhesion of the inner surface 208, 308, 408 and the outer surface 210, 310, 410 of the frame 202, 302, 402 to the inner coating 204, 304, 404 and the outer coating 206, 306, 406, respectively.

[0025] The inner coating 204, 304, 404 is made of a polymer material. The polymer material is expanded polytetrafluoroethylene (ePTFE). The properties of ePTFE provide the inner coating 204, 304, 404 with a smooth, soft, and flexible inner surface for the sleeve body 200, 300, 400, which reduces the risk of clot formation and reduces friction and stiction when inserting a device through the expandable sleeve or removing a device from the expandable sleeve. For example, the ePTFE inner coating 204, 304, 404 provides a low-coefficient-of-friction surface in contact with a device being advanced through the sleeve body, thereby reducing the associated frictional forces. In the present disclosure, the outer coating 206, 306, 406 may be made of a single layer or multiple layers of polymer materials (e.g.,a multi-layer coating), as described in more detail below.

[0026] Suitable primers for applying ePTFE coatings to a surface are known and will not be described in detail here. ePTFE is hydrophobic, so suitable primers can take this into account. An example of a suitable primer is one that creates amine groups on its surface (e.g., a co-deposition of polyethyleneimine (PEI) and polydopamine). Surface treatments such as plasma dipping and oxygen plasma have been used to create a suitable surface for ePTFE deposition. With reference to the Fig. In a first aspect, the ePTFE inner coating 204 is applied to the inner surface 208 of the braided frame 202, as stated above. Alternatively, the frame 202 can be formed by patterning a hypotube with a lumen therein. In one aspect, the hypotube is patterned by laser cutting. The pattern introduced into the hypotube serves to control the axial expansion, radial expansion, and / or compression of the lumen.

[0027] In the present embodiment of the Fig. 2-4, the outer coating 206 is also composed of a polymeric material; the polymeric material used to form the outer coating 206 in this embodiment may be the same as or different from that of the ePTFE inner coating 204 described above. In the illustrated embodiment, the outer coating 206 is composed of thermoplastic polyurethane (TPU). The properties (or characteristics) of ePTFE and TPU advantageously provide smooth, soft, and flexible inner and outer surfaces, respectively, of the sleeve body 200 to reduce friction and stiction during insertion of a device through the expandable sleeve or removal of a device from the expandable sleeve, thereby requiring relatively less force to insert and remove the device (e.g., an intracardiac heart pump) than to insert and remove the device from a sleeve body without coatings.In addition, the smooth surface of the TPU outer coating 206 advantageously reduces the risk of blood clot formation on the surface of the expandable sleeve body 200. Furthermore, in some cases, an inner coating of ePTFE may allow some fluid permeability through the coating, and a fluid-impermeable material may be selected for the outer layer. Such a construction may help reduce or prevent unwanted leakage or seepage from the sleeve body and maintain hemostasis. However, it should be noted that the introducer sheaths described herein are not limited to sheaths with a fluid-impermeable outer layer.For example, in some embodiments, a sleeve comprising only an ePTFE inner coating may provide a sufficient degree of fluid impermeability to prevent leakage or seepage and maintain hemostasis during use.

[0028] In another aspect, the outer coating may comprise an outer layer (e.g., TPU) that may be partially molded into the microporous structure of the ePTFE.

[0029] With reference to the Fig. 5 to 7, in a second aspect, the ePTFE inner coating 304 is applied to the inner surface 308 of the braided frame 302, as stated above. As with the first aspect described above, the frame 302 may alternatively be formed by patterning a hypotube with a lumen therein. The hypotube is patterned by laser cutting. The pattern introduced into the hypotube serves to control the axial expansion, radial expansion, and compression of the lumen. An inner primer 312 and an outer primer 314 are formed on the inner and outer surfaces of the frame 302.

[0030] In the present embodiment, the inner coating 304 and the outer coating 306 are made of the same material. For example, the inner coating 304 and the outer coating 306 are made of ePTFE. Similar to the first aspect, the properties of ePTFE advantageously provide smooth, soft, and flexible inner and outer surfaces for the sleeve body 300 to reduce friction and stiction during insertion of a device through the expandable sleeve or removal of a device from the expandable sleeve, thereby requiring relatively less force to insert and remove the device (e.g., an intracardiac heart pump) than to insert and remove the device from a sleeve body without coatings. Furthermore, the smooth surface of the outer ePTFE coating 306 advantageously reduces the risk of blood clots forming on the surface of the expandable sleeve body 300.

[0031] With reference to the Fig. 8-10, in a third aspect, the ePTFE inner coating 404 is applied to the inner surface 408 of the braided frame 402, as stated above. The primer 412 is located between the inner surface 408 of the frame 402 and the ePTFE inner coating 404. In the present view, the outer coating 406 has a multi-layer configuration and thus consists of several polymer materials. In the illustrated view, the outer coating 406 may include an ePTFE layer 416 and a TPU layer 418. As can be seen from the Fig. 9 and Fig. As can be seen in Figure 10, the ePTFE layer 416 of the outer coating 406 adheres to the outer surface 410 of the frame 402 (with the primer 414 disposed between the multilayer outer coating 406 and the frame 402). The TPU layer 418 is applied to the ePTFE layer 416 to improve the biocompatibility of the ePTFE layer 416. Like the first and second aspects, the ePTFE inner coating 404 and the outer multi-layer coating 406 advantageously provide smooth, soft, and flexible inner and outer surfaces, respectively, for the sleeve body 400 to reduce friction and stiction when a device is inserted through or removed from the expandable sleeve, thereby requiring a relatively lower force to insert and remove the device (e.g., an intracardiac heart pump) than the force required to insert and remove the device from a sleeve body without coatings.In addition, the smooth surface of the multi-layer outer coating 406 advantageously reduces the risk of blood clot formation on the surface of the expandable sleeve body 400.

[0032] In the aspects described above, the sleeve body 200, 300, 400 may contain silicone oil impregnated into the ePTFE inner coating 204, 304, 404 to reduce or prevent the penetration of air, water, and / or blood into the ePTFE inner coating 204, 304, 404. The silicone oil also reduces the coefficient of friction of the ePTFE. The coefficient of friction can be reduced by up to half. The silicone oil is incorporated into the ePTFE coating by applying it to the surface against which the ePTFE inner coating will be brought into contact. The silicone oil then penetrates the porous ePTFE. When applying the silicone oil to a surface to penetrate the ePTFE, the viscosity of the silicone oil is low enough that the silicone oil penetrates through the ePTFE and is retained by the microporous structure of the hydrophobic ePTFE to create an elastic, lubricious surface.The ability of silicone oil to be retained by ePTFE is indirectly proportional to the density and pore size of the ePTFE (i.e., for lower-density (i.e., more porous ePTFE) to exhibit similar silicone oil retention capacity, a higher viscosity is required). To achieve the desired lubrication and retention of silicone oil, the viscosity of silicone oil for an ePTFE with a density of approximately 0.4 g / cm. 3 For example, 350 cP. Viscosities greater than 350 cP do not provide the same lubrication effect. For example, a viscosity of 1000 cP provides only half the lubrication effect of a viscosity of 350 cP for ePTFEs with densities in the range of those mentioned above.

[0033] In the aspects described above, the inner coating 204, 304, 404 has a tubular shape and extends over the entire length of the sleeve body 200, 300, 400, as shown in the Fig. 2, Fig. 5 and Fig. 8. The outer coating 206, 306, 406 also has a tubular shape and extends the length of an elongated portion 201, 301, 401 of the sleeve body 200, 300, 400. Thus, the outer coating 206, 306, 406 extends between the proximal end of the sleeve body 200, 300, 400 and a split 203, 303, 403, which is a point at which the outer surface of the sleeve body 200, 300, 400 begins to taper in both the inner and outer diameters. As shown, beyond the tapered portion is a smaller diameter portion with constant inner and outer diameters. As shown, the outer coating 206, 306, 406 does not extend beyond the tapered section or the constant diameter / smaller diameter section.

[0034] Although the inner and outer diameters of the sleeve bodies are largely a matter of design choice, the inner diameter of the main sleeve body is believed to be approximately 4 mm. "Approximately," as used herein, means plus or minus twenty-five percent of the stated value, or as one of ordinary skill in the art would understand the term in the particular context. The inner coating 204, 304, 404 and the outer coating 206, 306, 406 may have any suitable thickness. In one aspect, the thickness of each of the inner coating 204, 304, 404 and the outer coating 206, 306, 406 is approximately 0.05 mm. A lumen 205, 305, 405 of the sleeve body 200, 300, 400 may have any suitable size. Preferably, the lumen 205, 305, 405 of the sleeve body 200, 300, 400 has an inner diameter of 4 mm. A tapered portion 207, 307, 407 of the sleeve body 200, 300, 400 can have any suitable size.Preferably, the length of the tapered portion 207, 307, 407 is between 0.1 mm and 5 mm, and the diameter of the opening 209, 309, 409 at the distal end 211, 311, 411 of the tapered portion 207, 307, 407 is between about 3.7 mm and about 3.9 mm.

[0035] Described herein is an introducer sheath assembly comprising: a tubular frame having a lumen therein, the tubular frame configured to temporarily expand from a first diameter to a second, larger diameter when a portion of a medical device having a diameter greater than the first diameter passes through the tubular frame; a coating adjacent an inner surface of the tubular frame, the coating formed of expanded polytetrafluoroethylene (ePTFE); and a fitting connected to a proximal end of the tubular frame, the fitting including a hemostasis valve.

[0036] In one aspect, the ePTFE coating is applied to the inner surface of the tubular frame. In another aspect, a primer is formed between the ePTFE coating and an inner surface of the lumen defined by the tubular frame. In another aspect, an outer coating is formed on an outer surface of the tubular frame.

[0037] The frame may be composed of a braided nitinol tube and a laser-machined hypotube. The outer coating may be composed of thermoplastic polyurethane, such as expanded polytetrafluoroethylene (ePTFE). In one aspect, the outer coating is multi-layered. For example, the outer coating may comprise two layers, wherein a first layer may be formed over the outer surface of the frame, and wherein the first layer may be thermoplastic polyurethane. The second of the two layers of the outer coating may be formed over the first layer, wherein the second layer comprises expanded polytetrafluoroethylene.

[0038] Also described herein is an expandable sleeve body comprising a tubular frame having a lumen therein, the frame having spaces therebetween, the frame being expandable to a larger diameter and contractable to a smaller diameter, and also being flexible; an inner coating formed over a surface of the lumen defined by the tubular frame; and an outer coating formed over an outer surface of the frame.

[0039] In one embodiment, the sleeve body may include a primer formed between the inner coating and the surface of the lumen defined by the tubular frame. The primer may be formed between the outer coating and the outer surface of the frame. The frame may be a braided nitinol tube or a laser-machined hypotube.

[0040] In one aspect of the sleeve body, the inner coating may be made of expanded polytetrafluoroethylene. The outer coating may be made of thermoplastic polyurethane, such as expanded polytetrafluoroethylene.

[0041] In another aspect, the outer coating may be multi-layered. For example, the outer coating may have two layers, wherein a first layer may be formed over the outer surface of the frame, and wherein the first layer may be thermoplastic polyurethane. The second layer of the two layers of the outer coating may be formed over the first layer, and the second layer may be formed from expanded polytetrafluoroethylene.

[0042] Described herein is an introducer sheath assembly comprising a tubular frame having a lumen therein, the tubular frame configured to temporarily expand from a first diameter to a second, larger diameter when a portion of a medical device having a diameter greater than the first diameter passes through the tubular frame. The introducer sheath includes a coating adjacent to an inner surface of the tubular frame, the coating being comprised of expanded polytetrafluoroethylene (ePTFE), and a fitting connected to a proximal end of the tubular frame, the fitting including a hemostasis valve.

[0043] In one aspect, the ePTFE coating is applied to the inner surface of the tubular frame. According to the above aspects, a primer may be formed between the ePTFE coating and an inner surface of the lumen defined by the tubular frame. In each of the above aspects, an outer coating is formed on an outer surface of the tubular frame. In each of the above aspects, the frame is selected from the group consisting of a braided nitinol tube and a laser-machined hypotube. The frame may be made of nitinol, and the outer coating may be made of thermoplastic polyurethane or expanded polytetrafluoroethylene. In one aspect, the outer coating is multilayered.In another aspect, the outer coating may comprise two layers, wherein a first layer is formed over the outer surface of the frame, the first layer comprising thermoplastic polyurethane. In another aspect, the second layer of the two layers of the outer coating is formed over the first layer, the second layer comprising expanded polytetrafluoroethylene.

[0044] Also described herein is an expandable sleeve body comprising a tubular frame with a lumen therein, the frame having interspaces, the frame being expandable to a larger diameter and contractible to a smaller diameter, and also being flexible. The sleeve body may comprise an inner coating formed over a surface of the lumen defined by the tubular frame and an outer coating formed over an outer surface of the frame.

[0045] In one aspect, a primer is formed between the inner coating and the surface of the lumen defined by the tubular frame. In another aspect, a primer is formed between the outer coating and the outer surface of the frame. In the above aspects, the expandable sleeve body may comprise the frame made of a braided nitinol tube or a laser-machined hypotube. In one aspect, the frame is made of nitinol. In the above aspects, the expandable sleeve body may comprise an inner coating made of expanded polytetrafluoroethylene. In the above aspects, the outer coating may be made of thermoplastic polyurethane. According to the above aspects, the outer coating may be made of expanded polytetrafluoroethylene. The outer coating may be multi-layered.In another aspect, the outer coating may comprise two layers, wherein a first layer is formed over the outer surface of the frame, the first layer comprising thermoplastic polyurethane. In another aspect, a second layer of the two layers of the outer coating is formed over the first layer, the second layer comprising expanded polytetrafluoroethylene.

[0046] From the foregoing and with reference to the various figure drawings, one skilled in the art will recognize that certain modifications can be made to the present disclosure without departing from the scope thereof. Although several embodiments of the disclosure have been shown in the drawings, it is not intended to limit the disclosure thereto, since it is intended that the disclosure be as broad as the art will allow and that the description be read in the same way. Therefore, the above description should not be construed as limiting, but merely as illustrative of certain embodiments. Those skilled in the art will envision other modifications that are within the scope and spirit of the appended claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 341,252

[0001] US 17 / 097,582

[0021] US 20210146111

[0021]

Claims

[1] An introducer sheath assembly comprising: a tubular frame having a lumen therein, the tubular frame configured to temporarily expand from a first diameter to a second, larger diameter when a portion of a medical device having a diameter greater than the first diameter passes through the tubular frame; a coating adjacent to an inner surface of the tubular frame, the coating being formed of expanded polytetrafluoroethylene (ePTFE); and a hub coupled to a proximal end of the tubular frame, the hub including a hemostasis valve. [2] The introducer sheath assembly of claim 1, wherein the ePTFE coating is applied to the inner surface of the tubular frame. [3] The introducer sheath assembly of claim 1 or 2, wherein a primer is formed between the ePTFE coating and an inner surface of the lumen defined by the tubular frame. [4] An introducer sheath assembly according to any one of claims 1 to 3, wherein an outer coating is formed on an outer surface of the tubular frame. [5] The introducer sheath assembly of any one of claims 1 to 4, wherein the frame is selected from the group consisting of a braided nitinol tube and a laser-machined hypotube. [6] An introducer sheath assembly according to any one of claims 1 to 5, wherein the frame is made of nitinol. [7] An introducer sheath assembly according to any one of claims 4 to 6, wherein the outer coating is made of thermoplastic polyurethane. [8] An introducer sheath assembly according to any one of claims 4 to 6, wherein the outer coating is made of expanded polytetrafluoroethylene. [9] An introducer sheath assembly according to any one of claims 4 to 8, wherein the outer coating is multi-layered. [10] An introducer sheath assembly according to any one of claims 4 to 9, wherein the outer coating comprises two layers, a first layer formed over the outer surface of the frame, the first layer comprising thermoplastic polyurethane. [11] The introducer sheath assembly of claim 10, wherein a second layer of the two layers of the outer coating is formed over the first layer, the second layer comprising expanded polytetrafluoroethylene. [12] Expandable sleeve body comprising: a tubular frame having a lumen therein, the frame having spaces therebetween, the frame being expandable to a larger diameter and contractable to a smaller diameter and also flexible; an inner coating formed over a surface of the lumen defined by the tubular frame; and an outer coating formed over an outer surface of the frame. [13] The expandable sleeve body of claim 12, wherein a primer is formed between the inner coating and the area of ​​the lumen defined by the tubular frame. [14] Expandable sleeve body according to claim 12, wherein a primer is formed between the outer coating and the outer surface of the frame. [15] Expandable sleeve body according to one of claims 12 to 14, wherein the frame is selected from the group consisting of a braided nitinol tube and a laser-machined hypotube. [16] Expandable sleeve body according to claim 15, wherein the frame is made of Nitinol. [17] Expandable sleeve body according to one of claims 12 to 16, wherein the inner coating consists of expanded polytetrafluoroethylene. [18] Expandable sleeve body according to one of claims 12 to 17, wherein the outer coating consists of thermoplastic polyurethane. [19] Expandable sleeve body according to one of claims 12 to 17, wherein the outer coating consists of expanded polytetrafluoroethylene. [20] Expandable sleeve body according to one of claims 12 to 15 and 17, wherein the outer coating is multi-layered. [21] The expandable sleeve body of claim 20, wherein the outer coating comprises two layers, a first layer formed over the outer surface of the frame, the first layer comprising thermoplastic polyurethane. [22] An expandable sleeve body according to claim 21, wherein a second layer of the two layers of the outer coating is formed over the first layer, and the second layer comprises expanded polytetrafluoroethylene. [23] Expandable sleeve according to any one of claims 17 to 19, wherein the expanded polytetrafluoroethylene is impregnated with silicone oil. [24] An expandable sleeve according to claim 23, wherein the expanded polytetrafluoroethylene is impregnated with silicone oil by capillary action of the silicone oil from a surface against which a layer of expanded polytetrafluoroethylene is placed. [25] Expandable sleeve according to claim 23, wherein the expanded polytetrafluoroethylene has a density of about 0.4 g / cm 3 and the silicone oil has a viscosity of about 350 cP.

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