Introducer sheath for blood vessel access
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ABIOMED EUROPE GMBH
- Filing Date
- 2024-07-31
- Publication Date
- 2026-04-20
AI Technical Summary
Existing introducer sheaths for vascular access pose a risk of damage and bleeding due to their diameter limitations and tissue recoil, especially with larger diameters, which can lead to prolonged tissue stretching and wound complications.
The introducer sheath incorporates a recoil section with higher radial compressibility at the puncture site to allow surrounding tissue to recoil, reducing damage and bleeding by partially closing the opening and acting as an anchor within the blood vessel.
The recoil section minimizes vascular damage and bleeding by allowing tissue to return to its original shape, enhancing healing and supporting the sheath's placement, while maintaining flexibility for insertion and anchoring.
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Abstract
Description
[Technical field]
[0001] The present invention relates to an introducer sheath for providing vascular access into the body of a patient. [Background technology]
[0002] Long-term vascular access is a common medical procedure used in several medical situations, including dialysis, for patients who require frequent dialysis treatments, chemotherapy, or the use of ventricular assist devices. Depending on the needs of the patient, different devices and different methods are used. Long-term vascular access for patients who require ventricular assist devices is commonly via open chest 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-chest surgery. The movement to use peripheral vessels rather than central cardiovascular vessels has been accompanied by the development of many specific devices and tools designed specifically for use in peripheral vessels. As larger devices are introduced, larger introducer sheaths are required. Vascular introducers are the most common devices developed to allow peripheral vascular access. To provide access to the vessel, the introducer sheath is usually directly punctured into the vessel at the puncture site, for example with the aid of a dilator.
[0004] An introducer sheath, which provides vascular access into a patient's body, 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, It is understood that the term "proximal" refers to a direction toward a user, such as a physician, and the term "distal" refers to a direction away from the user.
[0005] The diameter of the introducer sheath is a limiting factor in providing vascular access. On the one hand, the outer diameter is limited by the patient and the vessel to be accessed. An introducer sheath with a too large diameter may not be able to be introduced into the vessel or may injure the patient and lead to excessive bleeding. Usually, a larger diameter of the introducer further increases the risk of complications for the patient. 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 provide a minimum inner diameter that allows a medical device, such as a catheter or a catheter with an intravascular blood pump, to pass through the patient's vessel. For example, a medical device with a size of 14 French requires an introducer sheath with a size of 16 French or 17 French. In particular, an introducer sheath with a large diameter will enlarge the opening of the vessel and surrounding tissue at the puncture site.
[0006] Vascular tissue has a tendency to recoil when punctured, i.e., to return to at least a portion of its original shape. If the vascular tissue is kept stretched for an extended period of time, this tendency to recoil is reduced. Typically, vascular tissue will recoil to a certain degree, usually about 2 to 3 French, depending on the time it has been stretched. Furthermore, larger puncture diameters will result in greater recoil. Thus, when larger diameter introducers are used, tissue recoil will be greater than when smaller diameter introducers are used. Particularly with extended use, tissue will not recoil at the puncture site, which can lead to bleeding and larger wounds that must be closed. Summary of the Invention [Problem to be solved by 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. [Means for solving the problem]
[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] According to the invention, the tubular body of the introducer sheath comprises a recoil section, the radial compressibility of which is higher than the radial compressibility of at least a portion of the tubular body distal to the recoil section, preferably higher than the radial compressibility of the remaining portion of the tubular body. Radial compressibility refers to the ability of the tubular body to be radially compressed, low radial compressibility being associated with a "stiff" property, whereas high radial compressibility is associated with a "soft" property. During placement of the introducer sheath in the patient's vessel, the recoil section is positioned to extend across the puncture site. This configuration has several advantages. The tubular body has a recoil section positioned in the area of the puncture site, which allows the surrounding skin and vascular tissue to recoil, i.e., to return at least partially 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. Moreover, the distal end of the tubular body is sufficiently rigid to be inserted into the patient's blood vessel in a conventional manner.
[0010] The recoil section can reduce the risk of bleeding as well as reduce 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 area of the recoil section. Thus, the portion distal to the recoil section does not compress radially, and thus creates a plug-like effect acting on the inner wall of the vessel when partially retracted from the vessel, sealing the vessel opening. 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 sits against the tissue from inside 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] Furthermore, 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 deployed, thereby providing increased flexibility during use, for example when little space is available, and 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 around the recoil section.
[0012] The introducer sheath of the present invention allows the puncture site to recoil, i.e., to contract the 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, the tissue at the puncture site can at least partially recoil after the maximum diameter of the medical device or dilator is retracted from the introducer sheath or advanced beyond the puncture site through the introducer sheath, with the introducer sheath inserted into the patient's blood vessel. Again, the tissue surrounding the recoil portion may recoil even if 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, the 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 vasculature, 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 such that the puncture site is located at the proximal portion of the tubular body. Since the recoil section is placed in the area of the puncture site, it is convenient for the recoil section to be 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 that is 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 halfway between the proximal and distal ends of the tubular body along the length 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, i.e. 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 soft portion with respect to the radial compressibility surrounded by a harder or stiffer portion of the tubular body. The recoil section preferably extends longitudinally of the tubular body only in a region of the tubular body that is adapted to be placed in the region of the puncture site of the patient's blood vessel.
[0015] In another embodiment, the recoil section extends from the proximal end of the tubular body towards 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 region of the puncture site. A longer recoil section allows the physician more flexibility in choosing the insertion depth. Since the proximal end of the tubular body is not inserted into the patient's blood vessel, the part of the tubular body extending towards the proximal end may have radial compressibility like the recoil section, or a lower radial compressibility like the distal part of the tubular body.
[0016] To aid in the positioning of the introducer sheath, at least one of the proximal and distal ends of the recoil section, preferably both, may be marked with a radiopaque material. This allows the physician to observe the position of the introducer sheath by x-ray. 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 the 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 that extends 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 the blood vessel, blood enters the lumen and is detected from the outside. 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 blood vessel that both lumens are in fluid communication with the vessel. The introducer sheath is correctly placed with the recoil section located in the area of the puncture site when the first lumen, terminating at the distal end of the recoil section, indicates blood pressure, but the second lumen, terminating at the proximal end of the recoil section, does not indicate blood pressure.
[0017] Conveniently, the recoil section extends uniformly around the circumference of the tubular body, i.e., completely uninterrupted around the circumference of the tubular body. However, the recoil section may be non-uniformly formed along the circumference of the tubular body, so long as high radial compressibility is ensured. For example, the recoil section may comprise first and second sections arranged alternately around the circumference of the tubular body, the first section having 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, in particular a non-circular cross section of the tubular body. Furthermore, the second section provides axial stiffness to the tubular body, which is advantageous, particularly during insertion of the introducer sheath into the patient's blood vessel. Any number is contemplated, but there may be, for example, 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 portion is greater than the radial compressibility of at least a portion of the tubular body distal to the recoil portion, 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 less 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 less than the wall thickness of the portion of the tubular body other than the recoil section. 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. In this embodiment, specifically, the recoil section is preferably made or constructed from the same material as the portion of the tubular body other than the recoil section 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 approximately the same as the wall thickness of the remaining portion of the tubular body, and the recoil section is preferably formed from a material having a stiffness less than the stiffness of the material of the remaining portion of the tubular body or at least a portion of the tubular body distal to the recoil section.
[0021] The introducer sheath may be configured for introducing a medical device into a patient's blood vessel. The medical device may comprise, for example, a catheter, preferably comprising an intravascular blood pump disposed at a 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 from polyethylene. Other preferred materials may be selected instead, such as polytetrafluoroethylene (PTFE). [Brief description of the drawings]
[0022] The foregoing summary of the invention, as well as the following detailed description of the preferred embodiments, are 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 it is not intended that the scope of the present disclosure be limited to the specific embodiments disclosed in the drawings. [Figure 1A] FIG. 1 illustrates 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] 13A-13C show an introducer sheath set according to another embodiment, comprising 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. [Diagram 3] 1A-1C show an embodiment of an introducer sheath. [Figure 4]FIG. 13 illustrates another embodiment of an introducer sheath. [Diagram 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] FIG. 13 shows details of another embodiment of an introducer sheath. [Figure 8] FIG. 13 shows details of another embodiment of an introducer sheath. [Figure 9] FIG. 13 shows details of yet another embodiment of an introducer sheath. [Figure 10] FIG. 13 illustrates a perspective view of a tubular sheath according to another embodiment. [Figure 11] FIG. 2 illustrates an introducer sheath being inserted into a patient's blood vessel. [Figure 12] FIG. 13 is a diagram showing an application example of an introducer sheath. [Figure 13] FIG. 13 shows another application example of the introducer sheath. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] 1A to 2B, different views of the introducer set 1 are shown. The introducer set 1 comprises 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 comprises 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 may be omitted in some applications. 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 when necessary or desired, specifically for splitting the hemostatic valve 14. A longitudinal notch 17 is provided in the hemostatic valve 14 to define a planned line of fracture. 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 combination with the introducer sheath of the present invention, particularly dilators without a balloon. The dilator 20 has 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) passing therethrough. That is, the dilator 20 can be placed over a guidewire inserted into a patient's vasculature using, for example, the Seldinger technique. The balloon 25 is disposed over and extends over 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, i.e., the balloon is pre-loaded prior to surgery. A fluid, such as air, is filled into the balloon 25 via the 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. When the dilator 20 is retracted after the assembly is inserted into the patient's vessel, the balloon 25 is deflated, decreasing the 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, is 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 that it does not require constant support by a balloon or other means.
[0026] 3-9 show 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 3, which is a portion that is more radially compressible than at least a portion of the tubular body 11 that is distal to the recoil section 31. Each of Figures 3-9 shows an introducer sheath 10 having a tubular body 11 having a proximal end 12 and a distal end 13. A hemostatic valve 14 is shown diagrammatically at the proximal end 12 of the tubular body 11. As explained above, the hemostatic valve 14 may be omitted or other means of preventing bleeding may 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 is 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 and the inner diameter may be larger 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, for example 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, which is the portion of the tubular body 11 that is disposed in the area of the vascular puncture site, has a low stiffness (i.e., a high radial compressibility) allowing 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, in order 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, in particular a thinner wall thickness, a different material, in particular a softer material, as compared to the remaining portions of the tubular body 11.
[0030] In the embodiment of FIG. 5, the recoil section 31 does not extend only to the area spaced apart between the proximal end 12 and the distal end 13 of the tubular body 11. The recoil section 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 section 31 coincides with the proximal end 12 of the tubular body 11, but the distal end 33 of the recoil section 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 is placed inside the blood vessel. Making the recoil section 31 longer gives the physician more flexibility in selecting the insertion depth. In this embodiment, as in the embodiment of FIG. 3, the recoil section 31 is formed from a portion of the tubular body 11 that has a thin wall thickness. It will be appreciated that alternatively, or in addition, the tubular body 11 may have a constant wall thickness with the recoil section 31 being made from a different and more flexible material that is more compressible than the tubular body 11, as in the embodiment of FIG.
[0031] In the embodiment shown in Figure 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 appreciated 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 Figure 3 or Figure 4, that is, the increased radial compressibility may be achieved by modifying either or both of the shape and material of the tubular body 11.
[0032] In the embodiment of the introducer sheath 10 shown in FIG. 7, a first lumen 34 and a second lumen 35 are provided, as briefly described in connection with FIG. 1. The first lumen 34 extends from a proximal end of the introducer sheath 10, such as the hemostasis valve 14, through the proximal end 32 of the recoil section 31, and terminates the tubular body 11 substantially at the distal end 33 of the recoil section 31. The lumen 34 is used to sense pressure, 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 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 differential 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 differential is detected between the proximal end 32 and the distal end 33, indicating that the introducer sheath 10 is correctly positioned.
[0033] FIG. 8 illustrates an embodiment similar to that of FIG. 3, but where the recoil section 31 at its distal end 33 does not transition smoothly into the distal portion of the tubular body 11, it forms an abrupt transition, such as a step or pleat. This helps to 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 transitions smoothly, 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 Fig. 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 end 32 and the distal end 33 of the recoil portion 31 may be marked with a radiopaque substance or a radiopaque additive, such as metal rings 36, 37, in the material of the tubular body 11. It is understood 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 shows a perspective view of the tubular body 11 of an introducer sheath according to another embodiment. Unlike the other embodiments, the recoil section 31 is not uniformly formed around the circumference of the tubular body 11, but comprises separate sections 31a, 31b. The sections 31a, 31b may be arranged in an alternating manner, for example two sections 31a and two sections 31b. The sections 31a and 31b may be of the same size or different sizes. For example, the section 31a may have the same or substantially the same radial compressibility as the rest of the tubular body 11, resulting in stiffness and stability of the tubular body 11, especially in the axial direction. The section 31b may have a higher radial compressibility, for example by using a thinner wall or a softer material in this region compared to the rest of the tubular body 11. As a result, the recoil section 31 is compressed in a non-circular shape.
[0036] With reference to FIG. 11, the introducer sheath 10 is shown diagrammatically 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 section 31 allows recoil of the tissue 51 at the puncture site 52 and the opening of the blood vessel 50, i.e. the tubular body 11 is contracted in the area of the recoil section 31 by the force exerted by the surrounding tissue. The recoil of the tissue 51 and the contraction of the tubular body 11 caused by the recoil section 31 also reduces the risk of bleeding, since the contracted shape of the tubular body 11 provides a plug 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 a 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 nearly 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 that result in a non-circular shape, such as an oval, to 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 convenient to place 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 through a patient's blood vessels by a catheter 100 into the patient's heart to provide a ventricular assist device. Vascular access may be placed in the patient's groin (FIG. 12) or in a peripheral vessel in the patient's chest (FIG. 13).
Claims
1. An introducer sheath (10) for providing vascular access to the patient's body, It comprises a tubular body (11) having a proximal end (12) and a distal end (13), The distal end (13) is inserted into the patient's blood vessel, and the medical device (100) is configured to be inserted into the patient's blood vessel from the proximal end (12) through the tubular body (11) to the distal end (13). An introducer sheath comprising a tubular body (11) with a recoil portion (31), wherein the radial compressibility of the recoil portion (31) is higher than the radial compressibility of at least a portion of the tubular body (11) distal to the recoil portion (31), and the recoil portion (31) has a wall thickness (d) that is thinner than the wall thickness (D) of a portion of the tubular body (11) distal to the recoil portion (31).
2. An introducer sheath according to 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. An introducer sheath according to claim 1 or 2, The recoil portion (31) has a proximal end (32) and a distal end (33), An introducer sheath wherein the distal end (33) of the recoil portion (31) is spaced apart from the distal end (13) of the tubular body (11), and the proximal end (32) of the recoil portion (31) is spaced apart from the proximal end (12) of the tubular body (11).
4. An introducer sheath according to claim 1 or 2, 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. An introducer sheath according to any one of claims 1 to 4, wherein the recoil portion (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. An introducer sheath according to any one of claims 1 to 5, wherein the recoil portion (31) extends uniformly around the tubular body (11) in the circumferential direction of the tubular body (11).
7. An introducer sheath according to any one of claims 1 to 6, wherein the recoil portion (31) has a wall thickness (d) that is thinner than the wall thickness (D) of the portion of the tubular body (11) other than the recoil portion.
8. An introducer sheath according to any one of claims 1 to 7, wherein the recoil portion (31) has a wall thickness (d) of 0.3 mm or less.
9. An introducer sheath according to any one of claims 1 to 8, wherein the recoil portion (31) is made of the same material as the portion of the tubular body (11) other than the recoil portion.
10. An introducer sheath according to any one of claims 1 to 9, wherein the recoil portion (31) is made of a material having a lower rigidity than the material of the portion of the tubular body (11) other than the recoil portion.
11. It is an introducer set, The invention comprises an introducer sheath according to any one of claims 1 to 10 and a medical device (100, 101), The introducer sheath (10) is configured to introduce the medical devices (100, 101) into the patient's blood vessels (50), The aforementioned medical device is an introducer set comprising a catheter (100).
12. An introducer sheath according to claim 8, wherein the wall thickness (D) is less than 0.2 mm.
13. An introducer sheath according to claim 12, wherein the wall thickness (D) is less than 0.15 mm.
14. An introducer sheath according to claim 13, wherein the wall thickness (D) is less than 0.1 mm.
15. An introducer set according to claim 11, comprising an intravascular blood pump (101) disposed at the distal end of the catheter (101).