Malleable sheath body

Abstract

To provide an introducer sheath with malleability allowing larger medical devices to be passed through the introducer sheath.SOLUTION: In a rest state, an introducer sheath 100 forms an oval cross-section sized to encompass a catheter 121 and a medical device 120. In a constrained state when a blood pump assembly as the medical device 120 is within the introducer sheath 100, the cross-section of the introducer sheath 100 is circular. The introducer sheath allows larger medical devices to be passed through the introducer sheath, while still allowing other devices 122 to be inserted through the introducer sheath 100 after the blood pump has been guided therethrough. The perimeter of oval cross-section of the introducer sheath 100 is equal to the perimeter of the circular cross-section of the introducer sheath 100.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority from U.S. Provisional Patent Application No. 62 / 907,927, filed September 30, 2019, which is incorporated herein by reference. [Background technology]

[0002] background Blood pumps are often used in combination with other medical devices to support and treat patients with cardiovascular disease. Physicians may perform high-risk percutaneous coronary interventions (HRPCIs) while utilizing blood pumps to provide cardiac support during the procedure. Inserting the blood pump and other devices required for such procedures typically requires two to three separate access locations into the arterial system. Each additional access location within the vasculature requires more time to prepare the access point, additional introducers, occluders, and other devices, and can lead to complications at the surgical site. For some patients with cardiovascular disease, additional vascular challenges may result in only one available access point for arterial or venous access. The lack of available access points can prevent physicians from gaining access to the vasculature, resulting in reduced patient treatment opportunities.

[0003] Some physicians have attempted to address these issues by using a single access point to access a patient's vasculature and inserting multiple devices through a single introducer sheath, hub, and valve placed at that access point. Placing multiple devices using a single hub and introducer sheath can compromise the ability to maintain the position of the first device during the introduction and manipulation of the second device, as well as potentially resulting in poor hemostasis from the introducer valve. Larger devices may not be able to fit through the introducer sheath and valve, and, once the larger device is placed, smaller devices may not be able to fit through the introducer sheath alongside the catheter of the larger device. Attempting to introduce large or multiple devices through a single conventional introducer sheath can result in damage to the introducer sheath and valve during insertion.

[0004] Given these challenges, some physicians may choose not to use cardiovascular support devices, such as blood pumps, when performing vascular interventions due to the difficulty of preparing multiple access sites to the vasculature. In such cases, physicians may proceed with PCI, such as the introduction of stents, balloons, prosthetic valves, additional catheters, guides, or atherectomy tools, without providing concurrent cardiac support from a blood pump. This decision may ultimately compromise the patient's ability to receive the mechanical circulatory support needed during the intervention.

[0005] Therefore, a need exists for new techniques to provide vascular access for multiple medical devices during cardiac interventions. Summary of the Invention

[0006] overview: The methods, systems, and devices described herein allow for the introduction of medical devices of various sizes through a flexible introducer sheath. The flexibility of the introducer sheath of the present invention allows for the introduction of larger medical devices, such as pumps, through the introducer sheath while still maintaining space for the insertion of catheters and other smaller devices through the introducer sheath after the pump has been guided through.

[0007] In one aspect, the blood pump assembly includes an introducer sheath having a proximal end and a distal end, a pump body extending within the introducer sheath, and a catheter interfaced with the pump body and extending proximally through the introducer sheath. The introducer sheath defines an oval cross-section sized to accommodate the catheter and the medical device.

[0008] In another aspect, the introducer sheath includes a proximal end with a first opening; a distal end with a second opening; and a sheath forming a lumen extending between the first and second openings. For example, the sheath may be sized for insertion into a patient's artery or vein. The first opening has a first cross-sectional shape in a resting state and a second cross-sectional shape in a restrained state. The circumference of the first cross-sectional shape is approximately the same as the circumference of the second cross-sectional shape. The first cross-sectional shape may be oval, and the second cross-sectional shape may be more circular. The oval cross-sectional shape of the first opening in the resting state allows multiple devices and catheters to be inserted through the introducer simultaneously, while the circular cross-sectional shape in the restrained state allows larger diameter devices to be inserted through the introducer sheath as needed. In some embodiments, the introducer sheath is flexible and passively forms a circular or irregular shape when a larger diameter device is inserted through the lumen of the introducer sheath. For example, the introducer sheath may be sized to allow a blood pump to pass through the lumen when the introducer sheath is in a restrained state having a circular cross-sectional shape, and a second medical device (such as a catheter, stent, or other device) may be passed through the lumen along with the blood pump catheter when the introducer sheath is in a resting state having an oval cross-sectional shape.

[0009] In another aspect, a method for introducing medical devices into a patient's vasculature via an introducer sheath configured to change shape during insertion into the patient's vasculature to allow two or more different medical devices to pass through the sheath. For example, the sheath may be sized and configured so that a blood pump can pass through the sheath lumen and be seated within the patient's vessel, and a stent, valve, or other interventional device can also pass through the sheath lumen. This allows such a multi-device assembly to be positioned through a single sheath introduced within a single access site. In some embodiments, the method involves inserting the distal end of an introducer sheath into the patient's vessel while leaving the proximal end of the introducer sheath extending out of the vessel. The introducer sheath has a cross-section configured to allow multiple medical devices to pass therethrough. In some embodiments, the sheath has a rest state and an extended state. The sheath may be configured to have an oval cross-sectional shape in a resting state; the oval shape allows two medical devices (such as a pump and a stent, each via a delivery catheter) to pass through the sheath simultaneously or in series. The method may include introducing a first medical device into the proximal end of the introducer sheath (e.g., the first medical device may include a distal medical device, such as a blood pump, and a proximal catheter); and guiding the first medical device (e.g., a blood pump) through the introducer sheath and out the distal end of the introducer sheath so that the proximal catheter of the medical device extends through the introducer sheath and out the proximal end of the introducer sheath. The method may further include introducing a second medical device (such as a stent, valve, or other device) into the proximal end of the introducer sheath (e.g., via a catheter); and guiding the second medical device through the introducer sheath while the proximal catheter of the first medical device remains in the introducer sheath. [Brief explanation of the drawings]

[0010] [Figure 1] Figure 1A shows a flexible introducer sheath in a stationary state, Figure 1B shows a flexible introducer sheath in a constrained state during insertion of a medical device into the introducer sheath, and Figure 1C shows a flexible introducer sheath in a stationary state during insertion of a second medical device into the introducer sheath. [Figure 2] 1 shows a cross section of a flexible introducer sheath in a resting state. [Figure 3] 1 shows a cross section of a flexible introducer sheath in a constrained state. [Figure 4] 1 shows a comparison of the cross-sectional shapes of the introducer sheath in a static and constrained state. [Figure 5] 1 shows a comparison of device sizes inserted into an introducer sheath in a static and constrained state. [Figure 6] 1 shows a flowchart illustrating a method for introducing a medical device into a patient's vasculature using a flexible introducer sheath. DETAILED DESCRIPTION OF THE INVENTION

[0011] Detailed Description: A flexible introducer sheath that can change between two or more cross-sectional shapes as a device is passed through the sheath allows larger medical devices, such as pumps, to be introduced through the introducer sheath while still maintaining space for inserting catheters and other smaller devices through the introducer sheath after the pump has been guided through.

[0012] By allowing multiple devices to be introduced through a single introducer sheath, only one access point into the patient's vasculature is required. Patients with only one available arterial or venous access point can undergo both PCI and cardiac support through the same access point, thus improving medical outcomes. Additionally, a single access point requires only one sterile field and one closure, which is less likely to result in complications.

[0013] 1A-C illustrate how a flexible introducer sheath allows for the insertion of multiple devices into the vasculature; as shown, the introducer sheath is in a static state before a device is introduced (FIG. 1A), in a constrained state while a larger medical device is being inserted through the introducer sheath (FIG. 1B), and returns to a static state after the larger medical device has passed through the introducer sheath (FIG. 1C).

[0014] 1A, a flexible introducer sheath 100 is shown in a resting state. The introducer sheath 100 has a proximal end 102, a first opening 104, and a sheath 106 forming a lumen 108 extending therethrough. The first opening has a width 110 and a height 112. The proximal end 102 of the introducer sheath 100 extends out of a patient's vessel 114 at an incision 111. A distal end (not shown) of the introducer sheath extends within the vessel 114, providing access to the vessel 114.

[0015] The first opening 104 has an oval cross-sectional shape in the resting state such that the width 110 is greater than the height 112. The resting state of the introducer sheath 100 is the shape to which the introducer sheath returns when it is unconstrained and there are no forces acting on the sheath 106. The sheath 106 has an oval cross-sectional shape along the length of the introducer sheath 100 from the proximal end 102 to the distal end (not shown). The sheath 106 has a smooth outer surface and a smooth inner surface within the lumen 108 to allow easy introduction into the vessel 114 and to facilitate the introduction of a medical device through the lumen 108 and into the vessel 114, respectively.

[0016] The introducer sheath 100 is formed from a material with a modulus of elasticity that allows the material to be flexible and pliable. As illustrated in FIG. 2, the introducer sheath 100 has an oval cross-section in its resting state, but the cross-sectional shape can be altered to allow larger devices to be passed through the lumen 108. The introducer sheath 100 is formed from a material with a modulus of elasticity between 10 MPa and 1000 MPa; and may be formed from any of thermoplastic polyurethane, polyether block amide plastic (PEBA), or thermoplastic elastomer, or any other suitable material. In some embodiments, the introducer sheath is formed from a material with a target material stiffness between 70A and 40D.

[0017] The oval cross-sectional shape of the introducer sheath 100 in its resting state may have a width 110 of 6.25 mm and a height 112 of 4 mm to 4.2 mm, or any other suitable dimensions. Ideally, the width 110 and height 112 of the introducer sheath 100 in its resting state are such that a 3 mm catheter and an 8 Fr sheath with a 10 Fr outer diameter can fit within the introducer sheath 100.

[0018] The incision 111 may be an arteriotomy oriented to align circumferentially with the vessel. The oval shape of the first opening 104 may be shaped to match the incision 111 in the vessel 114. Because the elasticity of the vessel 114 allows it to stretch in certain directions, an oval incision 111 may lead to improved results over circular or other shaped incisions. An oval incision 111 may also be easier to close after the procedure is complete. Additionally, the oval cross-section of the introducer sheath may allow for the introduction of additional or differently shaped devices than conventional introducer sheaths; conventional introducer sheaths are typically formed as completely round tubes that are most effective for the introduction of other round-shaped devices.

[0019] The patient's vessel may be accessed through an arteriotomy. In some embodiments, the size of the arteriotomy matches the dimensions of the introducer sheath. In some embodiments, the vessel is the femoral artery. In some embodiments, the vessel is the radial artery.

[0020] The proximal end 102 of the introducer sheath 100 may be coupled to a hub (not shown). The hub may include one or more access points and one or more valves through which medical devices may be guided into the introducer sheath 100. In some embodiments, the hub may provide a single access point coupled to the introducer sheath such that all medical devices to be inserted into the introducer sheath are guided through the same hub. In other embodiments, the hub may include multiple access points for introducing multiple medical devices into the vessel. Using the introducer sheath 100 with a hub designed with multiple access points allows for individual manipulation and positioning of medical devices within the vessel without concern for misalignment or movement of the medical devices when introduced through the same valve or hub. Furthermore, using an introducer sheath 100 with a hub designed to provide access to multiple devices improves patient safety because only one access point into the vessel is required and the hub, introducer sheath 100, and devices are less likely to be damaged or broken during introduction. An introducer sheath 100 designed to allow for the introduction of multiple devices through the sheath 106 can be used for a wider range of patients, including those with cardiovascular disease that limits the availability of venous or arterial access points.

[0021] 1B shows the flexible introducer sheath 100 in a constrained state during insertion of a first medical device 120 into the introducer sheath 100. As the first medical device 120 is threaded through the lumen 108, the introducer sheath 100 passively assumes a more circular shape. The introducer sheath 100 has a diameter of approximately 5 mm in the constrained state. In some embodiments, the circular cross-section of the introducer sheath is formed at an axial location along the introducer sheath that encloses a portion of the medical device.

[0022] The width 110 and height 112 of the introducer sheath 100 in the resting state change toward the circular constrained radius 105 shown in FIG. 1B in the constrained state; however, the introducer sheath 100 need not be truly circular. While the constrained state is conveniently illustrated in FIG. 1B as having a circular cross-section, in some embodiments, the constrained state is oval, but with dimensions different from the oval shape of the resting state shown in FIG. 1A. The introducer sheath 100 is passively manipulated into the constrained state by passage of a first medical device 120 through the lumen 108, and the actual shape of the lumen 108 and opening 104 of the introducer sheath 100 is determined by the dimensions of the first medical device 120 passing through the lumen 108. When the introducer sheath 100 has a truly circular cross-section in the maximum constrained state, the radius 105 is approximately 5 mm, allowing a 5 mm circular medical device to fit within the introducer sheath. In some embodiments, the circular radius 105 is 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 7 mm, or 8 mm. Ideally, the radius 105 of the introducer sheath 100 can accommodate a first medical device size 14 Fr.

[0023] In some embodiments, the first medical device 120 can be a blood pump, an aortic valve replacement device, or an endovascular aneurysm repair device. For example, in FIG. 1B, the first medical device 120 is illustrated as a blood pump. The blood pump can have a cannula, a rotatably driven impeller for pumping blood, and a catheter 121 extending proximally from the cannula. The catheter can include electrical wiring for controlling the blood pump. In some embodiments, the blood pump includes a rotor disposed within a shroud and a motor coupled to the catheter. In some embodiments, the blood pump further includes an introducer hub coupled to the proximal end of the introducer sheath. In some embodiments, the introducer hub includes more than one introducer port. In some embodiments, the introducer hub includes a valve.

[0024] 1C shows the flexible introducer sheath 100 in a resting state during insertion of a second medical device 122 into the introducer sheath 100. After the first medical device 120 (shown in FIG. 1B) passes through the introducer sheath 100, the introducer sheath 100 returns to its resting oval cross-sectional shape. The catheter 121 of the first medical device 120 still extends through the introducer sheath 100, connecting the first medical device 120 to the proximal end 102 of the introducer sheath 100. The catheter 121 of the first medical device 120 has a smaller diameter than the first medical device 120 itself. While the introducer sheath 100 is in its resting state and has an oval cross-sectional shape, it can accommodate an additional second medical device 122 next to the catheter 121 of the first medical device 120 to be introduced into the vessel 114 through the introducer sheath 100.

[0025] In some embodiments, the cross-section of the introducer sheath 100 is configured to change from a circular cross-section back to an oval cross-section when the pump body is distal to the distal end of the introducer sheath 100 and the catheter 121 extends from the pump body to the proximal end of the introducer sheath 100.

[0026] The introducer sheath 100 has the same outer circumference of the opening 104 whether the introducer sheath 100 is in a resting state or a restrained state. In its oval resting state, the introducer sheath 100 has a smaller cross-sectional area than in its more circular resting state. In its resting state, the introducer sheath 100 is statically oval and temporarily changes cross-sectional shape to a more circular cross-sectional shape to accommodate passage of a larger first medical device 120 through the lumen 108. The variable cross-sectional shape allows the introducer sheath 100 to accommodate larger devices through differently shaped sheath openings and sheaths with the same outer circumference than a statically round introducer sheath. For example, when the introducer sheath 100 is in its resting state, a sheath for use in PCI can be inserted through the introducer sheath 100 next to a 9 Fr catheter for a blood pump, but these two medical devices cannot pass together through a conventional rigid introducer sheath. A smaller cross-sectional area in the resting state is advantageous for using the introducer sheath 100 for longer durations within the patient's body, as it occupies a smaller portion of the vessel cross-section, which provides more flow through the sheath and increases distal perfusion.

[0027] Although the hub is not shown in Figures 1A-1C for clarity, the sheath attached to the hub may have a circular or oval shape. The minimum width of the oval cross-section, or the diameter of the circular cross-section, ideally can accommodate a 3 mm diameter catheter or a 10 Fr sheath. In some embodiments, the hub must be rigid, not flexible, and accommodate a device through the hub without changing the shape of the hub. The hub may have a larger cross-sectional area than the sheath in its resting state or in its restrained state. The sheath may have a circular or more circular cross-section at the attachment point to the hub, with a transition zone distal to the attachment and the resting state of the sheath distal to the transition zone. In some embodiments, the transition zone is less than 2 cm in length to avoid interaction with the arteriotomy.

[0028] 2 shows a cross-section of a flexible introducer sheath 200 in a resting state. As described above with respect to FIGS. 1A and 1C, the introducer sheath 200 has an oval cross-sectional shape in a resting state. The introducer sheath 200 (e.g., the introducer sheath 100 of FIGS. 1A-C) has a proximal end 202, a first opening 204, and a sheath 206 forming a lumen 208 extending therethrough. The first opening 204 has a width 210 and a height 212.

[0029] In the resting state, the introducer sheath 200 has an oval cross-section at the first opening 204 and maintains that cross-sectional shape along the length of the sheath 206. While in the resting state, the lumen 208 of the introducer sheath 200 also has an oval cross-section. The width 210 of the first opening 204 is greater than the height 212.

[0030] In some embodiments, the first opening 204 has a width 210 of 6.25 mm and a height 212 of 4 mm to 4.2 mm, or any other suitable dimensions. Ideally, the width 210 and height 212 of the first opening 204 of the introducer sheath 200 in its resting state are such that a 3 mm catheter and an 8 Fr sheath with a 10 Fr outer diameter can fit within the introducer sheath 200.

[0031] In some embodiments, the first opening 204 and a portion of the proximal end 202 of the sheath 206 are oval in cross-section while in a resting state, and the remainder of the length of the introducer sheath 200 is circular in shape or has a differently sized oval cross-sectional shape. The sheath 206 is flexible so that the introducer sheath 200 can bend to follow natural curves in the vasculature without kinking.

[0032] FIG. 3 shows a cross-section of a flexible introducer sheath 300 in a restrained state. As discussed above with respect to FIG. 1B, the introducer sheath 300 has a circular cross-sectional shape in the restrained state, or a cross-sectional shape that is more circular than the cross-section of the introducer sheath in the restrained state. The introducer sheath 300 (e.g., the introducer sheath 100 in FIG. 1B) has a proximal end 302, a first opening 304, and a sheath 306 forming a lumen 308 extending therethrough. The first opening has a width 310 and a height 312. Although the width 310 and height 312 are different from the width and height of the introducer sheath in the restrained state (e.g., in FIG. 2), the circumference of the first opening 304 is the same in both the restrained and restrained states. The restrained configuration has a smaller cross-sectional area than when in the restrained state.

[0033] In a constrained state, the introducer sheath 300 has a circular cross-sectional shape at the first opening 304 and along the length of the sheath 306. The introducer sheath 300 may be constrained by passage of a medical device having a cross-sectional dimension greater than the width 310 or height 312 of the first opening 304 of the introducer sheath 300, such that the cross-sectional shape of the first opening 304 changes to accommodate the medical device. The flexible material of the introducer sheath 300 allows the cross-sectional shape of the introducer sheath to change sufficiently to allow the medical device to pass through the lumen 306.

[0034] In some embodiments, the introducer sheath 300 does not have a perfectly circular cross-sectional shape in the restrained state. Instead, the introducer sheath 300 may continue to have an oval cross-sectional shape; however, the dimensions of the oval may be altered from the resting oval shape. In some embodiments, the introducer sheath 300 has a complex or irregular shape that mimics the shape of a device being passed through the introducer sheath 300. In some embodiments, the entire length of the sheath 306 from the proximal end 302 to the distal end (not shown) has a consistent cross-sectional shape. In other embodiments, only the portion of the introducer sheath 300 through which the medical device is currently passing has a circular or restrained cross-section.

[0035] In some embodiments, introducer sheath 300 changes its cross-sectional shape while one or more medical devices are passed through lumen 306. The medical devices may be a blood pump, an aortic valve replacement device, or an endovascular aneurysm repair device. Introducer sheath 300 returns to its resting oval cross-sectional state after the medical devices are guided through lumen 306 and into the vessel.

[0036] 4 shows a comparison of the cross-sectional shapes of introducer sheath 400 in a resting state 403 and a constrained state 401. In the resting state 403, introducer sheath 400 has a cross-section shaped as an oval having a width 407 and a height 409. In the constrained state 401, introducer sheath has a cross-section that is circular in shape and has a radius 405.

[0037] In the resting state 403, the introducer sheath 400 has a width 407 of approximately 6.25 mm and a height 409 of approximately 4 mm. In some embodiments, the introducer sheath 400 in the resting state has a width 407 that is 5.25 mm, 5.5 mm, 5.75 mm, 6 mm, 6.25 mm, 6.5 mm, 6.75 mm, 7 mm, 7.25 mm, 7.5 mm, 8 mm, 9 mm, or any other suitable width. In some embodiments, the introducer sheath 400 in the resting state has a height 412 that is 3 mm, 3.5 mm, 3.75 mm, 4 mm, 4.25 mm, 4.5 mm, 4.75 mm, 5 mm, or any other suitable height. Ideally, the width 407 and height 409 of the introducer sheath 400 in its resting state are such that a 3 mm catheter and an 8 Fr sheath with a 10 Fr outer diameter can fit within the introducer sheath 400.

[0038] In the constrained state 401, the width 407 of the introducer sheath 400 decreases while the height 409 increases to accommodate the size of the medical device being guided into and through the introducer sheath 400. The width 407 and height 409 may approach the radius 405 of the circle in the constrained state. The radius 405 of the circular cross-sectional shape is approximately 5 mm. In some embodiments, the radius of the circular cross-sectional shape is 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 7 mm, or 8 mm. For convenience, the constrained state 401 may be circular, as shown in FIG. 4 , but in some embodiments, the constrained state 401 is oval, but with dimensions different from the oval shape in the rest state. In some embodiments, the constrained state 401 has a complex or irregular cross-sectional shape, and the shape may reflect the shape and dimensions of the medical device being inserted through the introducer sheath 400. Ideally, the radius 405 of the introducer sheath 400 can accommodate a medical device size 14 Fr.

[0039] While the cross-sectional circumference of the opening in introducer sheath 400 remains constant in both the resting state 403 and the constrained state 401, the size of the medical device that can pass through the opening varies depending on the dimensions of the opening. Figure 5 shows a comparison of device sizes that can be inserted into introducer sheath 500 in the resting state 503 (e.g., resting state 403 in Figure 4) and the constrained state 501 (e.g., constrained state 401 in Figure 4).

[0040] The introducer sheath 500 in the restrained state 501 has a circular cross-sectional shape or a more circular cross-sectional shape than in the restrained state, allowing larger medical devices to pass through its lumen. The lumen of the introducer sheath 500 in the restrained state 501 is sized to accommodate, for example, two devices (511 and 513) of radius R1, or a single larger device of radius R3. The introducer sheath 500 in the restrained state 503 has an oval cross-sectional shape. The longer width of the oval shape allows the introducer sheath 500 in the restrained state 503 to accommodate multiple devices of various sizes; for example, the introducer sheath 500 in the restrained state 503 can accommodate a first device 515 of radius R1 and a second device 517 of a larger radius R3. The cross-sectional area of ​​the lumen in the restrained state 503 is smaller than the cross-sectional area in the restrained state 501.

[0041] The flexibility of the introducer sheath 500 allows for variation in the cross-sectional shape of the introducer sheath 500 when a larger device (such as a device with radius R3) is passed through the introducer sheath 500. When multiple medical devices are inserted through the introducer sheath 500 in the static state 503, a larger caliber medical device can be guided through the lumen of the introducer sheath 500 (e.g., second medical device 517) while other medical devices (e.g., first medical device 515) extend through the lumen of the introducer sheath.

[0042] In one example, introducer sheath 500 may assume a circular cross-sectional constrained state 501 when a blood pump is inserted into a vessel through the lumen of introducer sheath 500. The circular cross-sectional shape of constrained state 501 can accommodate the large diameter of the blood pump as it passes through introducer sheath 500. For example, the blood pump may have a radius R3. Once the blood pump has passed through introducer sheath 500, a catheter (e.g., as first medical device 515) remains in the lumen of introducer sheath 500, and introducer sheath 500 returns to static state 503. Next, a second medical device 517 may be passed through introducer sheath 500 in static state 503 alongside the catheter (first medical device 515). The second medical device may be a balloon, stent, prosthetic valve, second catheter, guide, or atherectomy tool. The second medical device 517 is not passed through a conventional rigid introducer sheath alongside the catheter (first medical device 515). By being able to change its cross-sectional shape to accommodate a medical device being guided through a lumen, the introducer sheath of the present invention is more versatile and provides a mechanism for a physician to safely gain access to a patient's vasculature for cardiovascular interventions.

[0043] Although the resting state is described herein as having an oval cross-sectional shape, while the resting state is described as a sheath with a more circular cross-sectional shape, it is contemplated that the resting state may have a circular cross-section to allow passage of larger diameter medical devices, and that the resting state of the introducer sheath may have an oval shape to accommodate multiple devices of smaller diameters and sizes.

[0044] In some embodiments, a therapy is provided using a first medical device within the patient's vasculature. In some embodiments, an electrical signal is provided to the first medical device through a proximal catheter of the first medical device. In some embodiments, a therapy is provided using a second medical device within the patient's vasculature.

[0045] FIG. 6 shows a flowchart 600 illustrating a method for introducing a medical device into a patient's vasculature using a flexible introducer sheath. In step 602, the distal end of an introducer sheath (e.g., introducer sheath 100 in FIGS. 1A-C, introducer sheath 200 in FIG. 2, introducer sheath 300 in FIG. 3, introducer sheath 400 in FIG. 4, or introducer sheath 500 in FIG. 5) is inserted into a patient's vasculature. The introducer sheath has an oval cross-sectional shape in a resting state such that, in the absence of forces acting on the introducer sheath, the introducer sheath has an oval cross-sectional shape along its length from its proximal end to its distal end. In some embodiments, the introducer sheath has an oval cross-sectional shape only at its proximal end or along some portion of the introducer sheath.

[0046] In step 604, a first medical device is introduced into the proximal end of the introducer sheath, forming a circular cross-sectional shape in the introducer sheath as the first medical device passes through the introducer sheath. The introducer sheath is formed as a flexible sheath that passively assumes a circular shape when a medical device larger than the dimensions, such as the width or height, of the introducer sheath opening in the resting state is introduced into the introducer sheath. The introducer sheath opening has the same circumference in the oval resting state as in the constrained circular state, but the dimensions are changed to allow the medical device to pass through the introducer sheath. The introducer sheath opening has a smaller cross-sectional area in the resting state compared to the constrained state. In step 606, the first medical device is guided through the introducer sheath and out the distal end of the introducer sheath. The first medical device has a catheter extending proximally from a body of the first medical device, and the proximal catheter extends through the introducer sheath from a distal end of the introducer sheath to a proximal end of the introducer sheath. The first medical device may be a blood pump, an aortic valve replacement device, or an endovascular aneurysm repair device.

[0047] In step 608, a second medical device is introduced into the proximal end of the introducer sheath; the introducer sheath returns to its resting oval cross-sectional shape after the first medical device has passed through the introducer sheath. The second medical device may be a balloon, stent, prosthetic valve, second catheter, guide, or atherectomy tool. The introducer sheath is sized to accommodate the second medical device as well as the proximal catheter of the first medical device in the resting state. In step 610, the second medical device is guided through the introducer sheath while the proximal catheter of the first medical device remains in the introducer sheath.

[0048] A flexible introducer sheath that can passively change cross-sectional shape from an oval resting state to a more circular or fully circular cross-sectional shape when a larger medical device is passed through the sheath lumen allows multiple medical devices to pass through a single introducer sheath, reducing the need for multiple access points. The flexible cross-sectional shape of the introducer sheath further allows for the passage of larger medical devices while maintaining a resting cross-sectional shape that provides a better shape for the arteriotomy and allows multiple smaller devices to be extended therethrough during a cardiovascular procedure.

[0049] The use of a flexible introducer sheath capable of changing cross-sectional shape, along with a hub having multiple access points for introducing multiple medical devices, allows a physician to insert devices through a single access point in a vessel and maintain the relative position of devices during the introduction and manipulation of other devices, promoting patient safety and efficient treatment of the patient.

[0050] In some embodiments, a second arteriotomy is made in the second vessel and a sheath, catheter, or medical device is inserted through the second arteriotomy.

[0051] The foregoing is merely illustrative of the principles of the present disclosure, and the device of the present invention may be practiced in other aspects of the present description, which are presented for purposes of illustration and not limitation. It should be understood that the device disclosed herein, while shown for use in percutaneous insertion of a heart pump, may also be adapted for use in devices in other applications requiring hemostasis.

[0052] Variations and modifications will occur to those skilled in the art after reviewing this disclosure. The features of the present disclosure may be implemented in any combination and subcombination (including multiple subsidiary combinations and subcombinations) with one or more other features described herein. The various features described or illustrated above, including components thereof, may be combined or integrated into other systems. Additionally, certain features may be omitted or not implemented.

[0053] Examples of modifications, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the scope of the information disclosed herein. All references cited herein are incorporated by reference in their entirety and made a part of this application.

[0054] Exemplary embodiments: Aspect A: A1: an introducer sheath having a proximal end and a distal end; a pump body configured to extend within the introducer sheath; a catheter configured to interface with the pump body and to extend proximally through the introducer sheath; Equipped with the introducer sheath forms an oval cross-section sized to contain the catheter and medical device; Blood pump assembly. A2: The blood pump assembly of A1, wherein the pump body includes a rotor disposed within a shroud and a motor, the motor being connected to the catheter. A3: The blood pump assembly of any one of A1 to A2, wherein the cross section of the introducer sheath is configured such that the introducer sheath is circular when the pump body is within the introducer sheath. A4: The blood pump assembly of any one of A1 to A3, wherein the cross-section of the introducer sheath is configured such that the introducer sheath changes from a circular cross-section back to an oval cross-section when the pump body is distal to the distal end of the introducer sheath and the catheter extends from the pump body to the proximal end of the introducer sheath. A5: The blood pump assembly of any one of A3 to A4, wherein the introducer sheath has an oval cross section in a free state. A6: The blood pump assembly of any one of A2 to A5, wherein the introducer sheath has a circular cross section in the restrained state. A7: The blood pump assembly of any one of A2 to A6, wherein the circumference of the introducer sheath is configured to be constant between an oval cross-section and a circular cross-section. A8: Any one of A2 to A7, wherein the oval cross-section of the introducer sheath has a first cross-sectional area and the circular cross-section of the introducer sheath has a second cross-sectional area, the second cross-sectional area being larger than the first cross-sectional area. A9: A8 blood pump assembly, wherein the first cross-sectional area of ​​the oval cross-section of the introducer sheath is configured to accommodate a 3 mm catheter and an 8 Fr sheath. A10: Any one of A7-A9 blood pump assemblies, wherein the oval cross section of the introducer sheath has a height of about 4 mm and a width of about 6.25 mm. A11: The blood pump assembly of any one of A7 to A10, wherein the height and width of the oval cross section of the introducer sheath are dependent on the size of the medical device. A12: The blood pump assembly of any one of A7 to A11, wherein the height and width of the oval cross section of the introducer sheath is configured to match the size of the arteriotomy. A13: The blood pump assembly of any one of A7 to A12, wherein the height and width of the oval cross section of the introducer sheath are constant from the proximal end to the distal end of the introducer sheath. A14: The blood pump assembly of any one of A1 to A13, wherein the introducer sheath is a 14 Fr introducer sheath. A15: The blood pump assembly of any one of A2 to A14, wherein the circular cross section of the introducer sheath has a diameter of 5 mm. A16: The blood pump assembly of any one of A2 to A15, wherein the circular cross section of the introducer sheath has a constant diameter from the proximal end to the distal end of the introducer sheath. A17: The blood pump assembly of any one of A1 to A16, wherein the outer surface of the introducer sheath is configured to be smooth from the proximal end to the distal end of the introducer sheath. A18: The blood pump assembly of any one of A1 to A17, wherein the introducer sheath is configured to have a material stiffness of 70A to 40D. A19: The blood pump assembly of any one of A1 to A18, wherein the introducer sheath is configured to have an elastic modulus of 10 MPa to 1000 MPa. A20: The blood pump assembly of any one of A1 to A9, wherein the introducer sheath comprises one of thermoplastic polyurethane, polyether block amide plastic (PEBA), or a thermoplastic elastomer. A21: The blood pump assembly of any one of A1 to A20, further comprising an introducer hub coupled to a proximal end of the introducer sheath. A22: The blood pump assembly of A21, wherein the introducer hub includes more than one introducer port. A23: The blood pump assembly of A21 or A22, wherein the introducer hub includes a valve. A24: The blood pump assembly of any one of A1 to A23, wherein the medical device is a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool. Aspect B: B1: a proximal end having a first opening; a distal end having a second opening; a sheath forming a lumen extending between the first opening and the second opening; Equipped with the first opening is configured to have a first cross-sectional shape in a resting state and a second cross-sectional shape in a restrained state; and the circumference of the first cross-sectional shape is the same as the circumference of the second cross-sectional shape; Introducer sheath. B2: The introducer sheath of B1, wherein the first cross-sectional shape is oval. B3: The introducer sheath of B1 or B2, wherein the second cross-sectional shape is circular. B4: The introducer sheath of any one of B1 to B3, wherein the first opening is configured to have a second cross-sectional shape when a device is pushed through the first opening and into the lumen. B5: The introducer sheath of B4, wherein the first opening is configured to return from the second cross-sectional shape to the first cross-sectional shape after the device is passed through the lumen. B6: The introducer sheath of B5, wherein the height and width of the first opening in the first cross-sectional shape depend on the size of the device. B7: The introducer sheath of B6, wherein the height and width of the first opening in the first cross-sectional shape are configured to accommodate a 3 mm catheter and an 8 Fr sheath. B8: The introducer sheath of B7, wherein the height of the first opening in the first cross-sectional shape is about 4 mm and the width of the first opening in the first cross-sectional shape is about 6.25 mm. B9: The introducer sheath of any one of B1 to B8, configured so that the cross-sectional area of ​​the first opening in the first cross-sectional shape is smaller than the cross-sectional area of ​​the first opening in the second cross-sectional shape. B10: The introducer sheath of any one of B1 to B8, wherein the height and width of the first opening in the first cross-sectional shape are configured to match the size of the arteriotomy. B11: The introducer sheath of any one of B1 to B10, wherein the dimension of the first opening in the first cross-sectional shape is constant along the length of the sheath. B12: The introducer sheath of any one of B1 to B11, wherein the outer periphery of the first opening is configured to be constant between the first cross-sectional shape and the second cross-sectional shape. B13: The introducer sheath of any one of B1 to B12, wherein the first opening has an inner diameter of about 5 mm in the second cross-sectional shape. B14: The introducer sheath of B13, wherein the lumen is configured to have an inner diameter equal to an inner diameter of the first opening in the second cross-sectional shape. B15: The introducer sheath of any one of B1 to B14, wherein the first opening is configured to have an outer diameter of 14 Fr when in the second cross-sectional shape. B16: The introducer sheath of any one of B1 to B15, wherein the outer surface of the sheath is configured to be smooth from the proximal end to the distal end. B17: The introducer sheath of any one of B1 to B16, configured to have a material stiffness of 70A to 40D. B18: The introducer sheath of any one of B1 to B17, configured to have an elastic modulus of 10 MPa to 1000 MPa. B19: The introducer sheath of any one of B1-B18, comprising one of a thermoplastic polyurethane, a polyether block amide plastic (PEBA), or a thermoplastic elastomer. B20: The introducer sheath of any one of B1 to B19, the proximal end being configured to be coupled to an introducer hub. B21: The introducer sheath of any one of B1 to B20, wherein the device is one of a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool. Aspect C: C1: A method for introducing a medical device into the vasculature of a patient, comprising: inserting a distal end of an introducer sheath into the patient's vessel, the proximal end of the introducer sheath extending out of the vessel, the introducer sheath having an oval cross-sectional shape in a resting state; introducing a first medical device into the proximal end of the introducer sheath, the first medical device comprising a distal medical device and a proximal catheter; guiding the first medical device through the introducer sheath and out the distal end of the introducer sheath so that the proximal catheter of the medical device extends through the introducer sheath and out the proximal end of the introducer sheath; introducing a second medical device into the proximal end of the introducer sheath; and Guiding the second medical device through the introducer sheath while the proximal catheter of the first medical device remains in the introducer sheath. C2: The method of C1, wherein the step of introducing the first medical device forms a circular cross-sectional shape within the introducer sheath as the first medical device passes through the introducer sheath. C3: The method of C2, wherein the circular cross-section is formed in the introducer sheath at an axial location along the introducer sheath that encloses a portion of the medical device. C4: The method of C2 or C3, wherein the circular cross-sectional shape formed within the introducer sheath has a circumference equal to the circumference of the oval cross-sectional shape of the introducer sheath in the resting state. C5: The method of any one of C2 to C4, wherein the circular cross-sectional shape formed within the introducer sheath has a cross-sectional area that is greater than the cross-sectional area of ​​the oval cross-sectional shape of the introducer sheath in a resting state. C6: The method of any one of C2-C5, wherein a circular cross-section is formed in the introducer sheath along the length of the introducer sheath from the proximal end to the distal end. C7: The method of any one of C2-C6, wherein the introducer sheath forms an oval cross-sectional shape after the first medical device is guided out of the distal end of the introducer sheath. C8: The method of any one of C1-C7, wherein the first medical device is a blood pump. C9: The method of C8, wherein the blood pump includes a rotor disposed within the shroud and a motor coupled to the proximal catheter. C10: The method of any one of C1-C9, wherein the second medical device is a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool. C11: Providing therapy with a first medical device within the patient's vasculature. Any one of the methods C1 to C10, further comprising: C12: Providing an electrical signal to the first medical device through a proximal catheter of the first medical device. The method of any one of C1 to C11, further comprising: C13: Providing therapy with a second medical device within the patient's vasculature. The method of any one of C1 to C12, further comprising: C14: creating an arteriotomy in the vessel, the size of the arteriotomy matching the dimensions of the introducer sheath; and accessing the vessel of the patient through the arteriotomy The method of any one of C1 to C13, further comprising: C15: making an arteriotomy in the vessel, the size of the arteriotomy matching the dimensions of the introducer sheath; The method of C14, but further comprising creating an arteriotomy in the femoral artery. C16: making an arteriotomy in the vessel, the size of the arteriotomy matching the dimensions of the introducer sheath; The method of C14, further comprising creating an arteriotomy in the radial artery. C17: making a second arteriotomy in the second vessel; and introducing a sheath, catheter, or medical device through the second arteriotomy. The method of C14, further comprising:

Claims

1. a proximal end having a first opening; a distal end having a second opening; a sheath forming a lumen extending between the first opening and the second opening; Equipped with the first opening is configured to have a first cross-sectional shape in a resting state and a second cross-sectional shape in a restrained state; and the circumference of the first cross-sectional shape is the same as the circumference of the second cross-sectional shape; Introducer sheath.

2. The introducer sheath of claim 1, wherein the first cross-sectional shape is oval.

3. 3. The introducer sheath of claim 1, wherein the second cross-sectional shape is circular.

4. The introducer sheath of any one of claims 1 to 3, wherein the first opening is configured to have a second cross-sectional shape when a device is passed through the first opening and enters the lumen.

5. The introducer sheath of claim 4 , wherein the first opening is configured to return from the second cross-sectional shape to the first cross-sectional shape after the device is passed through the lumen.

6. The introducer sheath of claim 5, wherein the height and width of the first opening in the first cross-sectional shape depend on the size of the device.

7. 7. The introducer sheath of claim 6, wherein the height and width of the first opening in the first cross-sectional shape are configured to accommodate a 3 mm catheter and an 8 Fr sheath.

8. 8. The introducer sheath of claim 7, wherein the height of the first opening in the first cross-sectional shape is about 4 mm and the width of the first opening in the first cross-sectional shape is about 6.25 mm.

9. The introducer sheath of any one of claims 1 to 8, wherein the cross-sectional area of ​​the first opening in the first cross-sectional shape is configured to be smaller than the cross-sectional area of ​​the first opening in the second cross-sectional shape.

10. The introducer sheath of any one of claims 1 to 5, wherein the height and width of the first opening in the first cross-sectional shape are configured to match the size of the arteriotomy.

11. The introducer sheath of any one of claims 1 to 10, wherein the size of the first opening in the first cross-sectional shape is constant along the length of the introducer sheath.

12. The introducer sheath of any one of claims 1 to 11, wherein the circumference of the first opening is configured to be constant between the first cross-sectional shape and the second cross-sectional shape.

13. The introducer sheath of any one of claims 1 to 12, wherein the first opening has an inner diameter of about 5 mm in the second cross-sectional configuration.

14. The introducer sheath of any one of claims 1 to 12, wherein the lumen is configured to have an inner diameter equal to an inner diameter of the first opening in the second cross-sectional shape.

15. The introducer sheath of any one of claims 1 to 14, wherein the first opening is configured to have an outer diameter of 14 Fr when in the second cross-sectional shape.

16. The introducer sheath of any one of claims 1 to 15, wherein the outer surface of the introducer sheath is configured to be smooth from the proximal end to the distal end.

17. The introducer sheath of any one of claims 1 to 16, configured to have a material stiffness of between 70A and 40D.

18. 18. The introducer sheath of any one of claims 1 to 17, configured to have an elastic modulus of 10 MPa to 1000 MPa.

19. 19. The introducer sheath of any one of claims 1-18, comprising one of a thermoplastic polyurethane, a polyether block amide plastic (PEBA), or a thermoplastic elastomer.

20. The introducer sheath of any one of claims 1 to 19, wherein a proximal end is configured to be coupled to an introducer hub.

21. The introducer sheath of any one of claims 1 to 20, wherein the device is one of a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool.

22. an introducer sheath having a proximal end and a distal end; a pump body configured to extend within the introducer sheath; a catheter configured to interface with the pump body and to extend proximally through the introducer sheath; Equipped with a cross-section of the introducer sheath forming an oval cross-section sized to contain the catheter and medical device; Blood pump assembly.

23. 23. The blood pump assembly of claim 22, wherein the pump body includes a rotor disposed within a shroud and a motor, the motor being coupled to the catheter.

24. 24. The blood pump assembly of claim 22, wherein the cross-section of the introducer sheath is configured such that the introducer sheath is circular when the pump body is within the introducer sheath.

25. 25. The blood pump assembly of claim 24, wherein the cross-section of the introducer sheath is configured such that the introducer sheath changes from a circular cross-section back to an oval cross-section when the pump body is distal to the distal end of the introducer sheath and the catheter extends from the pump body to the proximal end of the introducer sheath.

26. 26. The blood pump assembly of claim 24, wherein the introducer sheath has an oval cross section in a free state.

27. 27. The blood pump assembly of claim 24, wherein the introducer sheath has a circular cross section in the restrained state.

28. 28. The blood pump assembly of claim 24, wherein the circumference of the introducer sheath is configured to be constant between an oval cross-section and a circular cross-section.

29. 29. A blood pump assembly as described in any one of claims 24 to 28, wherein the oval cross-section of the introducer sheath has a first cross-sectional area, and the circular cross-section of the introducer sheath has a second cross-sectional area, and the second cross-sectional area is larger than the first cross-sectional area.

30. 30. The blood pump assembly of claim 29, wherein the first cross-sectional area of ​​the oval cross-section of the introducer sheath is configured to accommodate a 3 mm catheter and an 8 Fr introducer sheath.

31. 31. The blood pump assembly of any one of claims 28 to 30, wherein the oval cross section of the introducer sheath has a height of about 4 mm and a width of about 6.25 mm.

32. 30. The blood pump assembly of any one of claims 24 to 29, wherein the height and width of the oval cross section of the introducer sheath depend on the size of the medical device.

33. 30. The blood pump assembly of any one of claims 24 to 29, wherein the height and width of the oval cross section of the introducer sheath are configured to match the size of the arteriotomy.

34. 30. The blood pump assembly of any one of claims 24 to 29, wherein the height and width of the oval cross section of the introducer sheath are constant from the proximal end to the distal end of the introducer sheath.

35. 35. The blood pump assembly of any one of claims 22 to 34, wherein the introducer sheath is a 14 Fr introducer sheath.

36. 36. The blood pump assembly of any one of claims 24 to 35, wherein the circular cross section of the introducer sheath has a diameter of 5 mm.

37. 37. The blood pump assembly of claim 24, wherein the circular cross-section of the introducer sheath has a constant diameter from the proximal end to the distal end of the introducer sheath.

38. 38. The blood pump assembly of claim 22, wherein the outer surface of the introducer sheath is configured to be smooth from the proximal end to the distal end of the introducer sheath.

39. 39. The blood pump assembly of any one of claims 22 to 38, wherein the introducer sheath is configured to have a material stiffness of between 70A and 40D.

40. 40. The blood pump assembly of any one of claims 22 to 39, wherein the introducer sheath is configured to have an elastic modulus of 10 MPa to 1000 MPa.

41. 31. The blood pump assembly of any one of claims 22 to 30, wherein the introducer sheath comprises one of a thermoplastic polyurethane, a polyether block amide plastic (PEBA), or a thermoplastic elastomer.

42. 42. The blood pump assembly of claim 22, further comprising an introducer hub coupled to a proximal end of the introducer sheath.

43. 43. The blood pump assembly of claim 42, wherein the introducer hub comprises more than one introducer port.

44. 44. The blood pump assembly of claim 42 or 43, wherein the introducer hub comprises a valve.

45. 45. The blood pump assembly of any one of claims 22 to 44, wherein the medical device is a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool.

46. A method for introducing a medical device into the vasculature of a patient, comprising: inserting a distal end of an introducer sheath into the patient's vessel, the proximal end of the introducer sheath extending out of the vessel, the introducer sheath having an oval cross section in a resting state; introducing a first medical device into the proximal end of the introducer sheath, the first medical device comprising a distal medical device and a proximal catheter; guiding the first medical device through the introducer sheath and out the distal end of the introducer sheath so that the proximal catheter of the medical device extends through the introducer sheath and out the proximal end of the introducer sheath; introducing a second medical device into the proximal end of the introducer sheath; and Guiding the second medical device through the introducer sheath while the proximal catheter of the first medical device remains in the introducer sheath.

47. 47. The method of claim 46, wherein a cross section of the introducer sheath forms a circular cross section when the first medical device is passed through the introducer sheath.

48. 48. The method of claim 47, wherein a circular cross section of the introducer sheath is formed at an axial location along the introducer sheath that encloses a portion of the medical device.

49. 49. The method of any one of claims 47 or 48, wherein the circular cross-section of the introducer sheath has a circumference equal to the circumference of the oval cross-section of the introducer sheath in the resting state.

50. 50. The method of any one of claims 47-49, wherein the circular cross-section of the introducer sheath has a cross-sectional area that is greater than the cross-sectional area of ​​the oval cross-section of the introducer sheath in the resting state.

51. The method of any one of claims 47 to 50, wherein the introducer sheath has a circular cross-section along the length of the introducer sheath from the proximal end to the distal end.

52. 52. The method of any one of claims 47 to 51, wherein a cross section of the introducer sheath forms an oval cross section after the first medical device is guided out of the distal end of the introducer sheath.

53. 53. The method of any one of claims 46-52, wherein the first medical device is a blood pump.

54. 54. The method of claim 53, wherein the blood pump comprises a rotor disposed within a shroud and a motor coupled to the proximal catheter.

55. 55. The method of any one of claims 46-54, wherein the second medical device is a balloon, a stent, a prosthetic valve, a second catheter, a guide, or an atherectomy tool.

56. Providing therapy with a first medical device within the patient's vasculature.

56. The method of any one of claims 46 to 55, further comprising:

57. Providing an electrical signal to the first medical device through a proximal catheter of the first medical device.

57. The method of any one of claims 46 to 56, further comprising:

58. Providing therapy with a second medical device within the patient's vasculature.

58. The method of any one of claims 46 to 57, further comprising:

59. creating an arteriotomy in the vessel, the size of the arteriotomy matching the dimensions of the introducer sheath; and accessing the vessel of the patient through the arteriotomy 59. The method of any one of claims 46 to 58, further comprising:

60. 60. The method of claim 59, wherein the vessel is the femoral artery.

61. 60. The method of claim 59, wherein the vessel is the radial artery.

62. making a second arteriotomy in the second vessel; and introducing a sheath, catheter, or medical device through the second arteriotomy.

60. The method of claim 59, further comprising:

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