Introducer sheath and introducer set

Abstract

It is an object of the present invention to provide an introducer sheath that reduces trauma to a patient's blood vessels. An introducer sheath (10) for providing vascular access into a patient's body includes a tubular body (11) having a proximal end (12) and a distal end (13), the distal end (13) configured for insertion into a patient's blood vessel (50) so that a medical device (100) can be inserted from the proximal end (12) through the tubular body (11) and from the distal end (13) into the patient's blood vessel (50). The tubular body (11) includes a recoil section (31) having a radial compressibility greater than the radial compressibility of at least a portion of the tubular body (11) distal to the recoil section (31). This allows the patient's blood vessel (50) and surrounding tissue (51) to recoil at a puncture site (52), which is beneficial to the patient, for example, in terms of wound healing.

Description

[Background technology]

[0001] The present invention relates to an introducer sheath for providing vascular access into a patient's body.

[0002] Long-term vascular access is a common medical procedure used in several medical situations, including dialysis, for patients requiring frequent dialysis treatments, chemotherapy, or the use of ventricular assist devices. Different devices and methods are used depending on the patient's needs. Long-term vascular access for patients requiring ventricular assist devices is commonly achieved via open-heart surgery and direct cardiovascular access.

[0003] In recent years, there has been a movement to access the cardiovascular system using peripheral vessels to avoid traumatic open-heart surgery. The movement to use peripheral vessels rather than central cardiac vessels has been accompanied by the development of many specific devices and tools designed specifically for peripheral use. As larger devices are introduced, larger introducer sheaths are required. Vascular introducers are the most common devices developed to enable peripheral vascular access. To provide vascular access, an introducer sheath is typically inserted directly into the vessel at the puncture site, e.g., with the aid of a dilator.

[0004] An introducer sheath for providing vascular access into a patient typically comprises a tubular body having a distal end and a proximal end, the distal end configured to be inserted into a patient's blood vessel so that a medical device can be inserted from the proximal end through the tubular body and into the patient's blood vessel from the distal end, with the term "proximal" being understood to refer to a direction toward a user, such as a physician, and the term "distal" being understood to refer to a direction away from the user.

[0005] The diameter of the introducer sheath is a limiting factor when establishing vascular access. On the other hand, the outer diameter is limited by the patient and vessel to be accessed. An introducer sheath with a diameter that is too large may not be able to be introduced into the vessel or may injure the patient and lead to excessive bleeding. Generally, a larger introducer diameter increases the risk of patient complications. Therefore, the diameter of the introducer sheath must be minimized, especially when the sheath diameter is relatively large. On the other hand, the introducer sheath must have a minimum inner diameter that allows medical devices, such as catheters or catheters with intravascular blood pumps, to pass through the patient's blood vessels. For example, a medical device with a 14 French diameter requires an introducer sheath with a 16 French or 17 French diameter. In particular, a larger diameter introducer sheath enlarges the opening in the vessel and surrounding tissue at the puncture site.

[0006] When punctured, vascular tissue has a tendency to recoil, meaning that it tends to return to at least a portion of its original shape. This tendency to recoil decreases when vascular tissue is stretched for an extended period of time. Typically, vascular tissue recoils to a certain degree, usually about 2 to 3 French, depending on the length of time it has been stretched. Furthermore, larger puncture diameters result in greater recoil. Therefore, when larger diameter introducers are used, tissue recoil is greater than when smaller diameter introducers are used. Particularly with prolonged use, tissue tends not to recoil at the puncture site, which can lead to bleeding and larger wounds that must be closed. Summary of the Invention

[0007] It is therefore an object of the present invention to provide an introducer sheath that reduces trauma to a patient's blood vessel, particularly at the puncture site.

[0008] This object is achieved according to the invention by an introducer sheath and a method as defined in the independent claims. Preferred embodiments and further developments of the invention are specified in the dependent claims which are dependent on the independent claims.

[0009] In accordance with the present invention, the tubular body of the introducer sheath includes a recoil section having a radial compressibility greater than that of at least a portion of the tubular body distal to the recoil section, preferably greater than that of the remaining portion of the tubular body. Radial compressibility refers to the ability of the tubular body to be radially compressed, with low radial compressibility being associated with a "stiff" property, while high radial compressibility is associated with a "soft" property. During placement of the introducer sheath in a patient's vessel, the recoil section is positioned to extend across the puncture site. This configuration has several advantages. Because the tubular body has a recoil section positioned in the area of ​​the puncture site, it can cause the surrounding skin and vascular tissue to recoil, i.e., at least partially return to its original shape. This is achieved by the high radial compressibility of the recoil section. Thus, the opening at the puncture site can be at least partially closed, thereby enhancing healing at the puncture site, reducing the likelihood of bleeding, and reducing damage to the patient's blood vessel. Furthermore, the distal end of the tubular body is sufficiently rigid to be inserted into the patient's blood vessel in the normal manner.

[0010] The recoil section can reduce the risk of bleeding in addition to reducing damage to the blood vessel at the puncture site. The increased radial compressibility of the recoil section causes the tubular body to contract in the region of the recoil section. Therefore, the portion distal to the recoil section does not compress radially, creating a plug-like effect that acts on the inner wall of the vessel and seals the opening of the vessel when partially retracted from the vessel. At the same time, the recoil section may act as an anchor to help support the introducer sheath within the patient's vessel. These effects are enhanced when the distal end of the recoil section is formed as a circumferential step or crease that lies against the tissue from the inside of the vessel at the puncture site. The proximal end of the recoil section may be smooth or stepped to facilitate insertion of the introducer sheath.

[0011] Additionally, the recoil section provides a flexible pivot point that allows a physician, such as a surgeon or cardiologist, to pivot the proximal portion of the tubular body, i.e., substantially the portion of the tubular body that is outside the patient's body, when the introducer sheath is being placed, thereby providing increased flexibility during use, for example, when little space is available, allowing the surgeon to move the proximal end of the tubular body in different directions, i.e., to select the insertion direction by pivoting the proximal end of the tubular body about the recoil section.

[0012] The introducer sheath of the present invention allows for recoil at the puncture site, i.e., allows for the contraction of an opening at the puncture site. For example, when the puncture site is dilated by a medical device inserted through the introducer sheath or by a dilator, tissue at the puncture site can at least partially recoil after the largest diameter portion of the medical device or dilator is retracted from the introducer sheath or advanced through the introducer sheath beyond the puncture site, with the introducer sheath still inserted into the patient's blood vessel. Again, tissue surrounding the recoil portion may recoil even when the introducer sheath remains in place. The tissue may recoil, for example, 2 to 3 French. In a typical introducer sheath without a recoil portion, tissue at the puncture site cannot recoil as long as the introducer sheath is inserted. The longer the introducer sheath remains inserted into the patient's vessel, the greater the risk that the tissue will lose its recoil properties after the introducer sheath is removed.

[0013] The recoil section is preferably located closer to the proximal end of the tubular body than the distal end. Typically, the introducer sheath is placed in the patient's blood vessel so that the puncture site is located in the proximal portion of the tubular body. Because the recoil section is placed in the area of ​​the puncture site, it is advantageous for the recoil section to be located closer to the proximal end of the tubular body than the distal end. However, in other embodiments, particularly when the portion of the tubular body inserted into the patient's blood vessel is shorter than the portion of the tubular body that remains outside the patient's body, the recoil section may be located closer to the distal end of the tubular body than the proximal end. In yet other embodiments, the recoil section may be equally spaced from both ends, i.e., located approximately midway along the length of the tubular body between the proximal and distal ends of the tubular body.

[0014] According to one embodiment, the recoil section has a distal end and a proximal end, the distal end of the recoil section being spaced apart from the distal end of the tubular body and the proximal end of the recoil section being spaced apart from the proximal end of the tubular body. That is, the recoil section is spaced apart from both ends of the tubular body. As a result, both the portion of the tubular body distal to the recoil section and the portion of the tubular body proximal to the recoil section have a lower radial compressibility than the radial compressibility of the recoil section. In other words, the recoil section forms a flexible portion relative to the radial compressibility surrounded by a stiffer or more rigid portion of the tubular body. Preferably, the recoil section extends longitudinally of the tubular body only within a region of the tubular body configured to be placed in the region of the puncture site in a patient's blood vessel.

[0015] In another embodiment, the recoil section extends from the proximal end of the tubular body toward the distal end of the tubular body. In contrast to the embodiment described above, the recoil section may alternatively be located directly at the proximal end of the tubular body. However, in this embodiment as well, the recoil section is located along the length of the tubular body so as to be located in the area of ​​the puncture site. A longer recoil section provides the physician with more flexibility in selecting the insertion depth. Because the proximal end of the tubular body is not inserted into the patient's vasculature, the portion of the tubular body extending toward the proximal end may have radial compressibility like the recoil section, or may have less radial compressibility like the distal portion of the tubular body.

[0016] To aid in positioning the introducer sheath, at least one of the proximal and distal ends of the recoil section, and preferably both ends, may be marked with a radiopaque material. This allows the physician to observe the position of the introducer sheath via radiography. The radiopaque material may be added to the material of the tubular body, for example, in the form of a metal ring or additive. Another feature that may aid in correct placement of the introducer sheath may be provided in the form of a pressure-sensing means. For example, a first lumen may be provided extending from the proximal end of the tubular body to the distal end of the recoil section, where it terminates. Thus, when the distal end of the recoil section enters a blood vessel, blood enters the lumen and is detected externally. Preferably, a second lumen extends from the proximal end of the tubular body to the proximal end of the recoil section, where it terminates. Thus, the pressure difference between the distal and proximal ends of the recoil section is measured. If the pressures are the same or nearly the same, the introducer sheath is inserted far enough into the vessel that both lumens are in fluid communication with the vessel. The introducer sheath is correctly placed with the recoil section positioned in the area of ​​the puncture site when the first lumen, terminating at the distal end of the recoil section, registers blood pressure, but the second lumen, terminating at the proximal end of the recoil section, does not register blood pressure.

[0017] The recoil section advantageously extends uniformly around the tubular body in the circumferential direction of the tubular body, i.e., extends completely uninterrupted around the circumference of the tubular body. However, the recoil section may be non-uniformly shaped along the circumference of the tubular body, so long as high radial compressibility is maintained. For example, the recoil section may include first and second sections alternately arranged around the circumference of the tubular body, with the first section providing high radial compressibility and the second section having substantially the same properties as the remaining portions of the tubular body. As a result, when the recoil section is radially compressed, the tubular body assumes a non-uniform shape, specifically, a non-circular cross section. Furthermore, the second section provides axial stiffness for the tubular body, which is advantageous, particularly during insertion of the introducer sheath into a patient's vessel. Any number of sections is contemplated, for example, there may be two first sections and two second sections. The second portions of the first end may have the same size or different sizes, particularly relative to the circumference of the tubular body.

[0018] The radial compressibility of the recoil section is greater than the radial compressibility of at least a portion of the tubular body distal to the recoil section, and is achieved by varying the geometry, specifically the wall thickness of the tubular body and / or the material of the tubular body.

[0019] In one embodiment, the recoil section has a wall thickness that is thinner than the wall thickness of the portion of the tubular body distally adjacent to the recoil section. Preferably, the recoil section has a wall thickness that is thinner than the wall thickness of the remaining portion of the tubular body. The recoil section of the tubular body may have a wall thickness of 0.3 mm or less, preferably 0.2 mm or less, more preferably 0.15 mm or less, and even more preferably 0.1 mm or less. Specifically, in this embodiment, it is preferred that the recoil section be made from or comprised of the same material as the remaining portion of the tubular body or at least the portion of the tubular body distal to the recoil section.

[0020] According to another embodiment, the recoil section has a wall thickness that is approximately the same as the wall thickness of the remaining portion of the tubular body, and is preferably formed from a material that has a stiffness that is less than the stiffness of the material of the remaining portion of the tubular body or at least the portion of the tubular body distal to the recoil section.

[0021] The introducer sheath may be configured to introduce a medical device into a patient's blood vessel. The medical device may include, for example, a catheter, preferably including an intravascular blood pump disposed at the distal end of the catheter. The tubular body may have a length of about 10 cm to about 30 cm, preferably about 20 cm. The diameter of the tubular body may range from about 12 French to about 18 French, preferably 14 French. The tubular body is preferably made of polyethylene. Alternatively, other suitable materials may be selected, such as polytetrafluoroethylene (PTFE). [Brief explanation of the drawings]

[0022] The foregoing summary of the invention, as well as the following detailed description of the preferred embodiments, is best understood when read in conjunction with the accompanying drawings, in which: For purposes of illustrating the present disclosure, reference is made to the drawings, but the scope of the present disclosure is not limited to the specific embodiments disclosed in the drawings. [Figure 1A] 1A and 1B show an introducer sheath set including an introducer sheath and a dilator in an assembled configuration. [Figure 1B] FIG. 1B shows the introducer sheath and dilator of FIG. 1A separated from each other. [Figure 2A] 10A-10C illustrate an introducer sheath set according to another embodiment, including an introducer sheath and a dilator in an assembled configuration. [Figure 2B] FIG. 2B shows the introducer sheath and dilator of FIG. 2A separated from each other. [Figure 3] 1A-1C illustrate an embodiment of an introducer sheath. [Figure 4]10A-10C show another embodiment of an introducer sheath. [Figure 5] 13A-13C show yet another embodiment of an introducer sheath. [Figure 6] 13A-13C show yet another embodiment of an introducer sheath. [Figure 7] 13A-13C show details of another embodiment of an introducer sheath. [Figure 8] 13A-13C show details of another embodiment of an introducer sheath. [Figure 9] 13A and 13B show details of yet another embodiment of an introducer sheath. [Figure 10] FIG. 10 shows a perspective view of a tubular sheath according to another embodiment. [Figure 11] FIG. 1 illustrates an introducer sheath being inserted into a patient's blood vessel. [Figure 12] 10A and 10B are diagrams showing application examples of an introducer sheath. [Figure 13] 10A and 10B show another application example of the introducer sheath. DETAILED DESCRIPTION OF THE INVENTION

[0023] 1A through 2B, different views of an introducer set 1 are shown. The introducer set 1 includes an introducer sheath 10 and a dilator 20, which are shown assembled in FIGS. 1A and 2A, respectively, and separated in FIGS. 1B and 2B, respectively. The introducer sheath 10 includes a tubular body 11 having a proximal end 12 and a distal end 13. A hemostatic valve 14 having a flexible membrane 18 is provided at the proximal end 12. However, it is understood that the hemostatic valve may be configured differently, or that in some applications, the hemostatic valve may be omitted. In the exemplary embodiment of the hemostatic valve 14, two handles 15, 16 are provided for manipulating the introducer sheath 10 and for separating the introducer sheath 10, specifically, for splitting the hemostatic valve 14, when necessary or desired. A longitudinal notch 17 is provided in the hemostatic valve 14 to define a predetermined fracture line. Lumens 34, 35 are provided extending through the valve 14 and the tubular body 11, as will be described in more detail below.

[0024] The illustrated dilator 20 is an exemplary dilator. It is understood that other suitable dilators may be used in conjunction with the introducer sheath of the present invention, particularly dilators without balloons. The dilator 20 includes a body 21 having a proximal portion 22 and a distal portion 23. The distal portion 23 includes a tapered end 24 that facilitates insertion into a patient's vasculature. In the embodiment of FIGS. 1A and 1B, ports 26, 28 are provided in the proximal portion 22. The port 28 is connected to an internal lumen configured to receive a guidewire (not shown) therethrough. That is, the dilator 20 can be placed over a guidewire inserted into a patient's vasculature using, for example, the Seldinger technique. A balloon 25 is disposed over and extends across most of the body 21 of the dilator 20, except for the tapered end 24 and the distal majority of the body 21. Balloon 25 can be inflated and deflated through a port 26 that is connected to balloon 25 through a lumen 27 in proximal portion 22 of body 21. Balloon 25 is made from a non-compliant material such as nylon.

[0025] The balloon 25 of the dilator 20 is utilized to support the introducer sheath 10 during insertion into the patient's vessel. The dilator 20 is inserted into the introducer sheath 10 with the balloon 25 deflated; that is, the balloon is pre-loaded prior to surgery. A fluid, such as air, is filled into the balloon 25 through port 26, inflating the balloon 25 so that the balloon 25 contacts the inner surface of the introducer sheath 10. This increases friction between the dilator 20 and the introducer sheath 10, stabilizing the introducer sheath 10 during insertion into the patient's vessel and preventing buckling of the introducer sheath 10. After the assembly is inserted into the patient's vessel, the balloon 25 deflates as the dilator 20 is retracted, reducing surface friction between the dilator 20 and the introducer sheath 10. The dilator 20 can then be retracted from the introducer sheath 10 substantially without interference. The dilator 20 and introducer sheath 10 are free to move. As noted above and as shown in Figures 2A and 2B, a dilator 20 can alternatively be provided without a balloon, and even without a balloon, be equivalent or similarly constructed to the dilator 20 shown in Figures 1A and 1B. It will be appreciated that the introducer sheath 10 may be sufficiently rigid so that it does not always require support by a balloon or other means.

[0026] 3-9 illustrate different embodiments of an introducer sheath 10 having a tubular body 11 with a recoil section 31, which is a portion of the tubular body 11 that is more radially compressible than the remaining portions of the tubular body 11. Alternatively, the recoil section 31 may be This is a portion that is more radially compressible than at least a portion of the tubular body 11 distal to the recoil section 31. Each of Figures 3 through 9 shows an introducer sheath 10 having a tubular body 11 with a proximal end 12 and a distal end 13. A hemostatic valve 14 is shown schematically at the proximal end 12 of the tubular body 11. As explained above, the hemostatic valve 14 can be omitted or other means for preventing bleeding can be used.

[0027] In the embodiment shown in FIG. 3 , the recoil section 31 is formed from a portion of the tubular body 11 having a wall thickness d, which is less than the wall thickness D of the remaining portion of the tubular body 11. This increases the radial compressibility of the recoil section 31. The wall thickness d may be 0.3 mm or less. The change in wall thickness of the tubular body 11 is preferably achieved by changing the outer diameter of the tubular body 11. Specifically, the inner diameter may be constant along the length of the tubular body 11, but the outer diameter of the tubular body 11 may be smaller at the recoil section 31. It will be appreciated that, alternatively, the outer diameter may remain constant while the inner diameter increases at the recoil section 31. The change in wall thickness of the tubular body 11 may also be a combination thereof. In this embodiment, the tubular body 11 is integrally formed from a single material, e.g., made from a single layer of one material.

[0028] The recoil section 31 has a proximal end 32 spaced from the proximal end 12 of the tubular body 11 and a distal end 33 spaced from the distal end 13 of the tubular body 11. This means that the tubular body 11 of the introducer sheath 10 is generally relatively stiff and easy to handle. Only the recoil section 31, the portion of the tubular body 11 that is positioned in the area of ​​the vascular puncture site, has a low stiffness (i.e., a high radial compressibility) that allows the tissue at the puncture site to recoil, i.e., return to at least a partial original configuration.

[0029] In the embodiment shown in Figure 4, the wall thickness of the tubular body 11 is substantially constant along the length of the tubular body 11. However, to provide high radial compressibility for the recoil section 31, the recoil section 31 is made from a material having a lower stiffness than the stiffness of the material of the remaining portions of the tubular body 11. It will be appreciated that the embodiments of Figures 3 and 4 may be combined, i.e., the recoil section 31 may be formed from a different wall thickness, particularly a thinner wall thickness, or a different, particularly more flexible, material, than the remaining portions of the tubular body 11.

[0030] In the embodiment of FIG. 5, the recoil portion 31 does not extend only over the region spaced apart between the proximal end 12 and the distal end 13 of the tubular body 11. Instead, the recoil portion 31 extends from the proximal end 12 of the tubular body 11 toward the distal end 13 of the tubular body 11. That is, the proximal end 32 of the recoil portion 31 coincides with the proximal end 12 of the tubular body 11, while the distal end 33 of the recoil portion 31 is spaced apart from the distal end 13 of the tubular body 11. The stiffness of the portion of the introducer sheath 10 outside the patient's body is less important than the stiffness of the portion that resides within the blood vessel. A longer recoil portion 31 provides the physician with greater flexibility in selecting the insertion depth. In this embodiment, as in the embodiment of FIG. 3, the recoil portion 31 is formed from a portion of the tubular body 11 having a thinner wall thickness. It will be appreciated that alternatively, or in addition, the tubular body 11 may have a constant wall thickness with the recoil portion 31 being made from a different, more flexible material that is more compressible than the tubular body 11, as in the embodiment of FIG.

[0031] In the embodiment shown in FIG. 6, the recoil section 31 forms a portion of the tubular body 11 having a reduced inner diameter. That is, unlike the previously described embodiments, the inner diameter of the tubular body 11 is not constant along its length. Furthermore, it will be understood that in all of the embodiments shown, the inner diameter of the tubular sheath 11 need not be constant along its length. The recoil section 31 may be formed, for example, according to either the embodiment of FIG. 3 or FIG. 4, meaning that increased radial compressibility may be achieved by varying the shape and / or material of the tubular body 11.

[0032] The introducer sheath 10 of the embodiment shown in FIG. 7 is provided with a first lumen 34 and a second lumen 35, as briefly described in connection with FIG. 1 . The first lumen 34 extends from the proximal end of the introducer sheath 10, such as the hemostasis valve 14, into the tubular body 11, through the proximal end 32 of the recoil section 31, and terminates in the tubular body 11 substantially at the distal end 33 of the recoil section 31. The lumen 34 is used for pressure sensing, for example, by means of a suitable pressure sensor. When the introducer sheath 10 is inserted sufficiently deep so that the distal end 33 of the recoil section 31 is placed in fluid communication with the patient's blood vessel, blood enters the lumen 34. The second lumen 35 is similar to the first lumen 34, but terminates in the tubular body 11 substantially at the proximal end 32 of the recoil section 31. When both the proximal end 32 and the distal end 33 of the recoil section 31 are positioned within the patient's blood vessel, substantially no pressure difference is detected. When the proximal end 32 is outside the patient's body and the distal end 33 is within the patient's blood vessel, a pressure difference between the proximal end 32 and the distal end 33 is detected, indicating that the introducer sheath 10 is correctly positioned.

[0033] FIG. 8 illustrates an embodiment similar to that of FIG. 3 , but at its distal end 33, the recoil section 31 does not transition smoothly into the distal portion of the tubular body 11, but forms an abrupt transition, such as a step or pleat. This helps prevent the introducer sheath 10 from backing out of the patient's vessel, as the step forms a stop for distal movement of the introducer sheath 10. At the proximal end 32, the recoil section 31 provides a smooth transition, facilitating insertion of the introducer sheath 10 into the patient's vessel. However, it will be appreciated that both the proximal end 32 and the distal end 33 may be formed as a step.

[0034] Another embodiment is shown in Figure 9, which is substantially similar to the above embodiment and may be combined with any of the described embodiments. To assist the physician in correctly positioning the introducer sheath 10 in the patient's blood vessel, i.e., with the recoil portion 31 in the area of ​​the puncture site, the proximal and distal ends 32, 33 of the recoil portion 31 may be marked with a radiopaque substance or radiopaque additive, such as metal rings 36, 37, within the material of the tubular body 11. It will be appreciated that only one of the ends 32, 33 may be marked with a radiopaque substance, or the entire recoil portion 31 may be marked, for example, by providing a radiopaque substance in the wall of the tubular body 11 in the area of ​​the recoil portion 31.

[0035] FIG. 10 illustrates a perspective view of a tubular body 11 of an introducer sheath according to another embodiment. Unlike other embodiments, the recoil section 31 is not uniformly formed around the circumference of the tubular body 11, but comprises separate sections 31a and 31b. The sections 31a and 31b may be arranged, for example, two sections 31a and two sections 31b, alternating with each other. The sections 31a and 31b may be the same size or different sizes. For example, the section 31a may have the same or substantially the same radial compressibility as the remaining sections of the tubular body 11, providing rigidity and stability for the tubular body 11, particularly in the axial direction. The section 31b may have a higher radial compressibility, for example, by using a thinner wall or softer material in this region compared to the remaining sections of the tubular body 11. As a result, the recoil section 31 is compressed in a non-circular shape.

[0036] Referring to FIG. 11 , an introducer sheath 10 is shown schematically inserted into a patient's blood vessel 50. The distal end 13 of the tubular body 11 is disposed within the blood vessel 50, while the proximal end 12 remains outside the patient's body. The introducer sheath 10 is inserted into the blood vessel 50 through a puncture site 52 and other tissue 51, such as skin tissue. The recoil portion 31 allows recoil of the tissue 51 at the puncture site 52 and the opening of the blood vessel 50; that is, the tubular body 11 is contracted in the area of ​​the recoil portion 31 by forces exerted by the surrounding tissue. The recoil of the tissue 51 and the contraction of the tubular body 11 that occurs at the recoil portion 31 also reduces the risk of bleeding, as the contracted shape of the tubular body 11 provides a plugging effect. Additionally, as shown by the arrow in FIG. 11 , the recoil section 31 provides a flexible pivot point about which the portion of the introducer sheath 10 proximal to the recoil section 31 can pivot to some degree, thereby allowing the physician more flexibility in selecting the insertion direction in which a medical device, such as a catheter having an intravascular blood pump, is inserted through the introducer sheath 10 and into the blood vessel 50.

[0037] Due to the higher blood pressure within the recoil section 31 relative to atmospheric pressure, the recoil section 31 remains circular or approximately circular and abuts the puncture site 52. Alternatively, and considering specifically the embodiment of FIG. 10 , the recoil section 31 may be formed with softer and stiffer sections, resulting in a non-circular shape, such as an oval, which may facilitate pivoting in a particular direction. As shown in FIG. 11 , a stop 38, such as a rubber ring, may be provided to prevent the introducer sheath 10 from entering the blood vessel 50. It is advantageous to position the stop 38 at the proximal end 32 of the recoil section 31 to facilitate positioning of the introducer sheath 10.

[0038] 12 and 13, an application of the introducer sheath 10 is shown. The introducer sheath 10 may be based on any one of the embodiments disclosed above. It is used to insert an intravascular blood pump 101 via a catheter 100 through the patient's blood vessels into the patient's heart to provide a ventricular assist device. Vascular access may be placed in a peripheral vessel in the patient's groin (FIG. 12) or in the patient's chest (FIG. 13).

Claims

1. An introducer sheath (10) for providing vascular access into a patient's body, comprising: A tubular body (11) having a proximal end (12) and a distal end (13), the distal end (13) is configured to be inserted into a blood vessel of a patient so that a medical device (100) can be inserted from the proximal end (12) through the tubular body (11) and from the distal end (13) into the blood vessel of the patient; the tubular body (11) comprises a recoil portion (31), the radial compressibility of the recoil portion (31) being greater than the radial compressibility of at least a portion of the tubular body (11) distal to the recoil portion (31); The recoil portion (31) extends longitudinally of the tubular body (11) only in a region of the tubular body (11) that is configured to be placed in the region of a puncture site in the patient's blood vessel.

2. 2. The introducer sheath of claim 1, wherein the recoil portion (31) is positioned closer to the proximal end (12) of the tubular body (11) than to the distal end (13).

3. The introducer sheath according to claim 1 or 2, The recoil portion (31) has a proximal end (32) and a distal end (33); The introducer sheath, wherein the distal end (33) of the recoil section (31) is spaced apart from the distal end (13) of the tubular body (11), and the proximal end (32) of the recoil section (31) is spaced apart from the proximal end (12) of the tubular body (11).

4. 3. The introducer sheath according to claim 1, wherein the recoil portion (31) extends from the proximal end (12) of the tubular body (11) toward the distal end (13) of the tubular body (11).

5. 5. The introducer sheath of claim 1, wherein the recoil section (31) has a proximal end (32) and a distal end (33), and at least one of the proximal end (32) and the distal end (33) is marked with a radiopaque material.

6. 6. The introducer sheath according to claim 1, wherein the recoil portion (31) extends uniformly around the tubular body (11) in the circumferential direction of the tubular body (11).

7. 7. The introducer sheath of claim 1, wherein the recoil section (31) has a wall thickness (d) that is thinner than a wall thickness (D) of a portion of the tubular body (11) distally adjacent to the recoil section (31).

8. 8. The introducer sheath according to claim 1, wherein the recoil portion (31) has a wall thickness (d) that is thinner than a wall thickness (D) of the tubular body (11) other than the recoil portion.

9. 9. The introducer sheath of any one of claims 1 to 8, wherein the recoil section (31) has a wall thickness (d) of 0.3 mm or less.

10. 9. The introducer sheath of any one of claims 1 to 8, wherein the recoil section (31) has a wall thickness (d) of less than 0.2 mm.

11. 9. The introducer sheath of any one of claims 1 to 8, wherein the recoil section (31) has a wall thickness (d) of less than 0.15 mm.

12. 9. The introducer sheath of any one of claims 1 to 8, wherein the recoil section (31) has a wall thickness (d) of less than 0.1 mm.

13. 7. The introducer sheath according to claim 1, wherein the recoil section (31) has a wall thickness that is the same as a wall thickness of the remaining portion of the tubular body (11).

14. 14. The introducer sheath according to any one of claims 1 to 13, wherein the recoil section (31) is made of a material having a stiffness lower than the stiffness of the material of the remaining portion of the tubular body (11).

15. 13. The introducer sheath according to any one of claims 1 to 12, wherein the recoil portion (31) is made of the same material as the remaining portion of the tubular body (11).

16. An introducer set, An introducer sheath according to any one of claims 1 to 15 and a medical device (100, 101), the introducer sheath (10) is configured to introduce the medical device (100, 101) into a patient's blood vessel (50); The introducer set, wherein the medical device comprises a catheter (100).

17. 17. The introducer set of claim 16, The medical device comprises an intravascular blood pump (101) disposed at the distal end of the catheter (100).

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