Sheath cutter with feeding mechanism

Abstract

The present disclosure is directed generally to introducer sheaths used in endoluminal catheterization for medical treatments. More particularly, the present disclosure is directed towards introducer sheaths that are expandable and tools for cutting them open.

Description

SHEATH CUTTER WITH FEEDING MECHANISMINCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

[0001] Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. For example, this application claims priority to U.S. Provisional Application No. 63 / 587330, titled SHEATH CUTTER WITH FEEDING MECHANISM and filed October 2, 2023, the entire contents of which is incorporated by reference herein in its entirety for all purposes and forms a part of this specification.TECHNICAL FIELD

[0002] The present disclosure is directed generally to introducer sheaths used in endoluminal catheterization for medical treatments. More particularly, the present disclosure is directed towards a systems and methods for cutting introducer sheaths.BACKGROUND

[0003] Introducer sheaths are used in medical interventions that employ access to a natural cavity or lumen of the patient, such as the vessels of the vascular system, as a method of gaining access to a target region of the patient’s body where material may be delivered, removed or an intervention can be performed. In a typical endovascular procedure, for example, access to the vasculature of the patient involves making a small percutaneous incision or puncture with a scalpel or introducer needle and delivering endovascular devices, such as catheters, into the lumen. An introducer sheath plays an important role in the procedure to protect the access puncture from excessive shear or frictional forces, to protect medical devices as they are delivered into the vasculature, to provide structural support, or to guide the delivery of a medical device through a desired luminal pathway. Compared to alternative approaches for accessing said target regions, such as open surgery, an endovascular approach or other approach utilizing an introducer sheath often has significant benefits such as reduced risk of infection or iatrogenic injury and quicker recovery.

[0004] A vast array of endoluminal medical devices has been developed for such less invasive approaches having dimensions and other features allowing them to be advanced into the natural lumens. Often such medical devices are elongate and tubular having outer diameters that are smaller than the smallest natural lumen through which they are intended to pass through to facilitate delivery, avoid injury, and to minimize interruption of lumen function, such as blood flow in the case of an endovascular procedure.

[0005] More recently, solutions have been explored for endoluminal delivery of devices that, including an introducer sheath, have a diameter that is large enough to occlude the lumen or even distend it. A device requiring such solutions may need to be larger as a result of design constraints. Furthermore, such solutions could permit patients, otherwise excluded from an endoluminal procedure due to narrow lumens or calcified vessels, to receive treatment. Challenges of endoluminal delivery of such larger devices may include disrupting a function of the luminal organ such as occlusion of the lumen or application of forces that are intolerable to the tissue. For example, for an endovascular procedure involving delivery of a medical device and an associated introducer sheath into a blood vessel having an inner diameter that is close to or even smaller than the maximum outer diameter of the introduced devices may result in occlusion of blood flow risking ischemia or injury to the blood vessel due to shear or distension. There is a need for solutions for delivering large devices with an endoluminal approach so the safety and procedural benefits of endoluminal approaches over surgery in general can be applied to larger devices.SUMMARY

[0006] This disclosure is related to methods, devices, and systems for introducer sheaths that are expandable, or that may be peeled apart, or both. The embodiments disclosed herein each have several aspects no single one of which is solely responsible for the disclosure’s desirable attributes. Without limiting the scope of this disclosure, its more prominent features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled “Detailed Description,” one will understand how the features of the embodiments described herein provide advantages over existing systems, devices, and methods for introducer sheaths.

[0007] The following disclosure describes non-limiting examples of some embodiments of introducer sheaths. For instance, other embodiments of the disclosed systems andmethods may or may not include the features described herein. Any of the features of the disclosed systems and methods may be combined, in whole or in part. The disclosed systems and methods may include additional or fewer features than described herein or be combined with different features than the examples described. Moreover, disclosed advantages and benefits can apply only to certain embodiments and should not be used to limit the disclosure.

[0008] In some aspects, the techniques described herein relate to a system for opening a lumen of an introducer sheath of a cardiac assist system, the system including: an introducer sheath including a lumen configured to contain a medical device; a cutting system including: a blade configured to cut a wall of the introducer sheath; a protection guide configured be received between the medical device and the wall of the introducer sheath; a feeding mechanism configured to guide the wall of the introducer sheath towards the blade.

[0009] In some aspects, the techniques described herein relate to a system, wherein the cutting system is configured to mate with an introducer hub.

[0010] In some aspects, the techniques described herein relate to a system, wherein the cutting system is integrated into an introducer hub.

[0011] In some aspects, the techniques described herein relate to a system, wherein the feeding mechanism includes at least one cog-like wheel including a plurality of teeth.

[0012] In some aspects, the techniques described herein relate to a system, wherein the plurality of teeth are configured to engage one or more reinforcement filaments of the introducer sheath.

[0013] In some aspects, the techniques described herein relate to a system, further including an actuator configured to actuate the feeding mechanism.

[0014] In some aspects, the techniques described herein relate to a system, wherein the actuator is configured to rotate the feeding mechanism about an axis transverse to the longitudinal axis of the introducer sheath.

[0015] In some aspects, the techniques described herein relate to a system, wherein the actuator includes a manual actuator geared to balance a speed of rotation of the feeding mechanism with a cutting force.

[0016] In some aspects, the techniques described herein relate to a system, wherein the actuator includes an electrical actuator.

[0017] In some aspects, the techniques described herein relate to a system, wherein the protection guide includes a partially closed lumen configured to receive the medical device.

[0018] In some aspects, the techniques described herein relate to a system, wherein the partially closed lumen is at least 50 percent closed.

[0019] In some aspects, the techniques described herein relate to a system, wherein the protection guide includes a C-shaped cross section.

[0020] In some aspects, the techniques described herein relate to a system, wherein the protection guide and the blade are formed from a single material.

[0021] In some aspects, the techniques described herein relate to a system, wherein the protection guide includes an approximately constant outer diameter and an approximately constant inner diameter from a proximal end to a distal end of the protection guide.

[0022] In some aspects, the techniques described herein relate to a system, wherein the protection guide includes an approximately constant inner diameter and a tapered outer diameter from a proximal end to a distal end of the protection guide, wherein the proximal end of the protection guide includes a larger outer diameter than the distal end of the protection guide.

[0023] In some aspects, the techniques described herein relate to a system, wherein an outer surface of the protection guide is contoured to encourage a cut portion of the introducer sheath to move away from a longitudinal axis of the introducer sheath.

[0024] In some aspects, the techniques described herein relate to a system, wherein an outer surface of the protection guide is smooth.

[0025] In some aspects, the techniques described herein relate to a system, wherein an outer surface of the protection guide is at least partially ridged.

[0026] In some aspects, the techniques described herein relate to a system, wherein the feeding mechanism includes a wheel including a three-dimensional shape configured to at least partially follow a contour of the wall of the introducer sheath.

[0027] In some aspects, the techniques described herein relate to a method of delivering a catheter placed in a natural lumen of a patient, the method including: delivering an introducer sheath into the patient's natural lumen; delivering a catheter through the introducer sheath; cutting the introducer sheath using a cutting system; and removing the introducer sheath from the catheter.BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings. In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the drawing, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

[0029] FIGURE 1 is a schematic illustration of an expandable introducer sheath and dilator inserted into an artery over a guidewire that may be used with a sheath cutting tool described herein.

[0030] FIGURE 2 is a cross sectional view of an example expandable introducer sheath and dilator such as shown in FIG. 1.

[0031] FIGURE 3 is a cross sectional view of a portion of an elongated tube of an example expandable introducer sheath in a neutral state.

[0032] FIGURE 4 is a cross sectional view of a portion of an elongated tube of an example expandable introducer sheath in an expanded state.

[0033] FIGURE 5A illustrates a cross sectional elevational view of an example introducer sheath, medical device, and cutting tool.

[0034] FIGURES 5B and 5C illustrate example aspects of an example introducer handle and example cutting tool.

[0035] FIGURE 6A illustrates a schematic elevational view of an example introducer sheath for delivery of a medical device and a first example cutting tool.

[0036] FIGURE 6B illustrates a cross sectional view of the system illustrated in FIG. 6A.

[0037] FIGURE 6C illustrates a schematic elevational view of an example introducer sheath having a tapered sheath protector.

[0038] FIGURE 7A illustrates a perspective view of an example introducer sheath, medical device, and cutting tool.

[0039] FIGURE 7B illustrates a cross sectional view of the system illustrated in FIG. 7A.DETAILED DESCRIPTION

[0040] The disclosure herein is related to introducer sheaths having expandable or adjustable lumen diameters, kits comprising the introducer sheath and other tools for use and methods of use. The following detailed description is directed to certain specific embodiments. In this description, reference is made to the drawings wherein like parts or steps may be designated with like numerals throughout for clarity. Reference in this specification to “one embodiment,” “an embodiment,” or “in some embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrases “one embodiment,” “an embodiment,” or “in some embodiments” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but may not be requirements for other embodiments. Reference will now be made in detail to embodiments of the invention, examples of which are illustrated in the5accompanying drawings.

[0041] Systems, devices and methods for controller cutting of introducer sheaths used for delivery, maintenance and retraction of a mechanical circulatory support device are disclosed herein.

[0042] A delivery system for introducing a medical device such as a percutaneous heart pump into a patient’ s vasculature can be used to protect the patient’ s arteriotomy and blood vessels while providing an access lumen to advance the medical device through. An introducer may be used to reduce or prevent blood from escaping the patient’s blood vessel and additionally hold the medical device in a desired position relative to the patient’s anatomy. The introducer may have asheath with a reinforcement braid or coil to improve strength and / or enable an expandable sheath feature. In some medical procedures, it is helpful to be able to remove an introducer in a radial direction from a medical device shaft (e.g., catheter) contained in its lumen. To do this, a continuously tubular introducer can be made discontinuous by, for example, generating an opening in the tubular introducer to release the medical device from the lumen.

[0043] To create an opening in a wall of a tubular introducer, the wall of the introducer may be cut with a blade in a cutting tool. In particular, the concepts disclosed herein may make it easier to make a longitudinal opening in introducers having reinforcement such as wire filaments or materials that are difficult to tear in a safe and controlled manner.General features of an example expandable introducer

[0044] Introducer sheaths may be used during most endoluminal interventions, for example for passage of a medical device through natural anatomical lumens such as bronchi, urethras, intestines, ducts, or blood vessels. For illustrative purposes, detailed descriptions of exemplary embodiments are focused on endovascular procedures and in particular for delivery of mechanical circulatory support (MCS) devices into an artery such as a femoral artery. However, it is to be understood that components and features disclosed herein may be combined with one another in any suitable way and may be adapted for passage of other medical devices or with other endoluminal interventions.

[0045] An introducer sheath, may be placed in a natural lumen, such as a blood vessel (e.g., femoral artery), through an orifice or aperture, such as an arteriotomy, and provide an access route into the natural lumen from outside of the body while protecting tissue and devices delivered through the introducer sheath. An introducer sheath may have features such as hemostasis valves, flushing ports, suture eyelets, and be used with a dilator. An expendable introducer sheath can temporarily expand in diameter to conform to and accommodate delivery of a medical device and contract towards a neutral state decreasing in diameter when radial force applied to the inner lumen is removed. For example, a medical device may include an elongate shaft with a component mounted to the distal end of the shaft wherein the component has a larger diameter then the shaft. Passage of the larger component through the introducer sheath may cause the sheath to expand in diameter and when the larger component passes out of the introducer the smaller shaft can remain connected to the larger component and slidably engaged within the introducer allowing theintroducer diameter to reduce in size. Furthermore, an expandable introducer may be retracted from the body, with the medical device shaft still contained in the introducer’s lumen, and be removed from the medical device shaft by cutting, tearing, or peeling a longitudinal opening along the length of the introducer. However, in the case of a reinforced introducer sheath, high forces may be required to cut the sheath, which may lead to poor control of the delivery system with previous systems.

[0046] Example introducers (which may include introducer sheaths and / or tubular bodies that may be configured to be cut by one or more cutting systems described herein) and / or insertion catheters are disclosed in Inti. Patent Publication No. PCT / US2021 / 071105, filed August 4, 2021, entitled INTRODUCER SHEATH HAVING AN ADJUSTABLE DIAMETER AND METHOD OF USE, which is hereby incorporated by reference herein in its entirety.

[0047] Figures 1-4 illustrate aspects of an example expandable introducer sheath 100 that may be used in conjunction with a controllable cutting system disclosed herein. Referring to Figure 1 and Figure 2, an expandable introducer sheath 100 may include an elongated tube 120 intended to be inserted into a natural lumen (e.g., through an arteriotomy 12 into a lumen 11 of an artery 10).

[0048] In some embodiments, the expandable introducer sheath 100 may include a proximal end 105 and a distal end 123. In some embodiments, the expandable introducer sheath 100 may include a hub 101 at the proximal end intended to remain exterior to the patient’s body. In some embodiments, the expandable introducer sheath may include an introducer lumen 121 passing through the hub and elongated tube and exiting at a proximal opening 104 in the hub and a distal opening 122 at the distal end of the elongated tube. In some embodiments, the introducer lumen is defined by a wall 125 of the elongated tube and a wall 106 of the hub. In some embodiments, the elongated tube 120 is adapted to have a neutral state and an expanded state. In some examples, the wall 125 may or may not be adapted to be opened or peeled apart in use along the full length of the introducer creating a longitudinal opening to allow contents (e.g., a medical device shaft 301) held within the introducer lumen to be released through the longitudinal opening. In some examples, the longitudinal opening may be generated by the cutting tool described herein and as shown in FIGS. 5-7B.Introducer hub

[0049] Referring to Figure 2, the hub 101 may be provided in a closed configuration and be opened by a cutting system 500, such as illustrated in FIG. 5A, to release a medical device 300 from the lumen 121 through a longitudinal opening. The hub may optionally contain one or more hemostasis valves 103 that allow delivery of tools such as guidewires, catheters and other medical devices through the hub while maintaining a fluid tight seal. For example, an expandable introducer sheath intended for delivery of an MCS device may have multiple hemostasis valves for 0” (103a), an 0.018” guidewire (103b), a 0.035” guidewire (103c), and a 5F or 6F diagnostic catheter (103d). The MCS device may be larger, for example having a diameter in a range of 14F to 18F, and be delivered through the multiple hemostasis valves using an insertion tool that spreads the hemostasis valves open to reduce insertion force and to protect the medical device (e.g., MCS device) from forces applied by the hemostasis valves. An insertion tool may for example have a handle that mates (e.g., locks, threads, click, friction fits) into the introducer hub 101 (e.g., handle cap 109), an elongated tube with a length that is at least long enough to extend into the strain relief 111 when the handle is mated with the introducer hub 101. The insertion tool’s elongated tube may be flexible enough to bend but have sufficient rigidity or hoop strength to resist compression by the hemostasis valves. A lumen passes through the insertion tool through which a medical device may be delivered. Optionally, the insertion tool may also have a hemostasis valve in its lumen adapted to seal against the medical device 300 or its shaft 301. Optionally, the insertion tool’s elongated tube may be adapted to be used as an introducer sheath, for example, having an atraumatic distal tip, which may have a soft durometer or taper or flexible expandable diameter. Optionally, an insertion tool dilator may be used to advance the extension tube of the insertion tool into a patient’s lumen (e.g., arteriotomy). An insertion tool dilator may be an elongated tube with a tapered distal end that is adapted to be assembled on a medical device shaft 301 and advanced through a lumen of the insertion tool’s extension tube to position the tapered distal end at the distal opening of the extension tube. For example, the insertion tube’s dilator may be provided in two halves or with a longitudinal opening for a user to assemble over a medical device shaft 301. The dilator may have an inner lumen sized to slidably accommodate a medical device shaft 301 and an outer diameter sized to be slidably accommodated by the insertion tool’s extension tube. The tapered distal end may taper from the outer diameter to the inner lumen diameter. In use the dilator may be pulled out of the insertion tool before removing the medical device from the patient so medical device can fit through the insertion tool’s extension tube. The hub 101 may optionallyhave a locking mechanism 108 on its proximal end 105, for example as part of a cap 109, configured to mate with a locking mechanism 112 on the dilator 110 or insertion tool. The locking mechanism 108, 112 may be for example a snap fit, friction fit, threaded or O-ring mating mechanism. The locking mechanism 112 can be positioned adjacent a dilator handle 232. The hub may also have a flushing port 102 that is attachable to a syringe and used to flush air from the lumen 121 prior to delivery into the body. The hub may also have a strain relief 111 that functions to hold the proximal end of the elongated tube to the handle and allow bending while avoiding kinking particularly where the flexible elongated tube 120 meets the rigid hub 101. The hub may also have suture eyelets 113 for suturing the hub to the patient’s skin, in particular to hold the introducer in place during longer procedures.Neutral state of example elongated tube

[0050] A cross-sectional close-up view of an embodiment of the elongated tube 120 in its neutral state is shown in Figure 3. The wall of the elongated tube 125 has a neutral state having a neutral state inner diameter 126, as shown in Figure 3, and may be temporarily radially expanded when radial force is applied to the inner surface of the wall, for example when a large component 302 of a medical device having a diameter 304 that is larger than the neutral state diameter 126 is passed through the introducer lumen 121 as shown in Figure 4. The neutral state of the elongated tube 120 may have an inner diameter 126 adapted to slidably engage components used in a catheterization procedure such as guidewires, dilators, diagnostic catheters, treatment catheters or a shaft of a medical device wherein radial expansion may not be necessary. For example, an expandable introducer sheath intended for transfemoral artery delivery of an MCS device may have an inner diameter 126 in a range of 6F to 10F (preferably 8F). In its neutral state the elongated tube shall be adapted to be kink resistant and have sufficient compressive and tensile strength to allow devices to be slidably advanced or retracted through the inner lumen and to be advanced through an artery or other natural lumen. The neutral state of the elongated tube 120 may have wall thickness 128 in a range of 0.3 to 0.5 mm and an outer diameter 127 equal to the inner diameter 126 plus two times the wall thickness 128. The neutral state outer diameter 127 may be chosen to allow sufficient functioning of the lumen through which the elongated tube is positioned in. For example, the outer diameter 127 of an expandable introducer sheath intended for transfemoral artery delivery of an MCS device may have a neutral state outer diameter 127 in a range of 6.5Fto 12F, preferably in a range of 8F to 11 F, which may apply minimal or no radial force to the artery wall and may allow sufficient blood flow through the femoral artery for the intended duration of implantation (e.g., several hours to several days) to avoid ischemia of the limb. Optionally, during delivery a dilator 110 (see Figure 2) having longitudinal rigidity may help to maintain the length of the elongated tube 120 to facilitate delivery into the patient’s lumen (e.g., artery).Expanded state of example elongated tube

[0051] The expanded state of the elongated tube 120, as shown in Figure 4, may have an expanded section 129 that is expanded as a result of radial force applied to the inner wall by the advancement of a device (e.g., a MCS device 302) having a diameter that is larger than the neutral state inner diameter 126, and at least a portion of the remaining length 130 of the elongated tube 120 of which radial force is not applied may resemble the neutral state and have a neutral state outer diameter 127. For example, the inner diameter of the expanded section 129 may conform to the diameter 304 of the device 302. The expanded section 129 may move along the length of the elongated tube 120 in reaction to a position of the device 302. For example, the inner diameter of the expanded section 129 may accommodate devices having a diameter up to 26F (preferably up to 19F), which may allow delivery of both a 14F and 18F MCS device. The wall thickness 131 of the expanded section may be equal to or less than the neutral state wall thickness 128. In some embodiments the wall thickness may decrease with expansion of diameter for example due to stretching or elongation of materials. Consequently, the outer diameter 132 in the expanded section 129 is a function of the device diameter 304 and wall thickness 131. The elongated tube 120 optionally may have a maximum expansion limit to prevent injury to the blood vessel or natural lumen. For example, in the case of transfemoral artery positioning a maximum expansion limit may be in a range of 19F to 27F and be a function of materials and design of the elongated tube. For example, an elongated tube may be made with an elastically stretchable material having an elongation factor equal to the maximum outer circumference divided by the neutral state circumference. For an illustrative example of an introducer intended for delivery of an MCS device, the elongated tube 120 may have an expansion ratio of the maximum expanded inner diameter to neutral state inner diameter in a range of 10:8 (i.e., 1.25) to 26:6 (i.e., 4.33), preferably in a range of 15:8 (i.e., 1.875) to 19:8 (i.e., 2.375).

[0052] The elongated tube 120 may have a length 133 adapted to traverse the natural lumen to provide access to a target location. For example, an introducer used to deliver an MCS device through a femoral artery to reach past a femoral bifurcation may have a neutral state length in a range of 250 to 350 mm, preferably a minimum of 275 mm. In some embodiments the length 133 of the elongated tube may shorten as a result of expanding a portion of the elongated tube. In some embodiments, the length 133 may be restricted from increasing beyond its neutral state by tension in longitudinal support wires, which in turn may prevent the neutral state inner diameter 126 of the lumen 121 from decreasing, which may facilitate passage of a medical device through the lumen 121.Further elongated tube features

[0053] Referring to Figure 3, the elongated tube 120 may be made with an expandable structural layer 140 and an expandable membrane 150. The expandable structural layer 140 may function to provide structural support to maintain a tubular shape, allow bending while resisting kinking over a bend radius of at least 10 cm, provide longitudinal strength in both compression and tension to allow the introducer to be advanced into a body lumen and pulled out of it, and to guide the delivery of a medical device through a desired lumen pathway. The expandable membrane 150 may function to seal the wall 125 of the elongated tube to prevent leakage of liquid such as blood, water, or saline through the wall for example, to allow air to be flushed from the lumen 121 prior to introduction into a body lumen or to prevent blood from leaking out of the lumen through the wall during use. The membrane may also function to protect tissue from injury by providing a smooth surface. Optionally, the elongated tube may have one or more (preferably two) longitudinal support wires to add longitudinal strength and limit elongation. Optionally, the elongated tube may further have an inner layer 134 that reduces friction and improves slidability between the inner layer and a medical device 302. Optionally, the elongated tube may further have an outer layer that reduces friction and improves slidability between the outer layer and tissue of the body lumen. The inner layer and outer layer may be an additional material (e.g., PTFE) laminated to the membrane 150 or structural layer 140, or a coating or surface treatment (e.g., micropatterned surface) on the expandable membrane and may have hydrophilic or lubricious properties. Optionally, a material in the elongated tube wall 125 may be impregnated with an agent(e.g., antibacterial, antimicrobial) that may reduce a risk of infection particularly when in use for several days.Example Sheath Cutting System

[0054] Aspects of an example sheath cutting system are illustrated in FIGS. 5A-7B. The cutting systems and methods described herein may be configured to cut introducer sheaths, including but not limited to introducer sheaths such as described above with reference to FIGS . 3 and 4. The cutting systems and methods described herein may be configured to cut expandable sheaths or fixed diameter sheaths. In some embodiments, the cutting systems and methods described herein may be configured to cut reinforced introducer sheaths. A reinforced introducer sheath may include, but is not limited to, a sheath having a metal or plastic reinforcement braid or coil. Such a sheath may advantageously improve hoop strength to resist kinking, but can be difficult to cut or tear and require high forces to do so. Systems and methods described herein relate to a controllable mechanism for cutting a braided or coiled sheath open so that it can be removed from a catheter in a radial direction. Advantageously, controlled cutting may improve ease of use and / or safety of an endovascular procedure. Furthermore, controlled cutting systems and methods disclosed herein may allow use of an expandable sheath having metallic or plastic filaments in an introducer.

[0055] FIGS. 5A-7B describe examples of sheath cutting systems operating on a sheath 100. As shown, the sheath 100 may include an elongate tube 120. However, one of skill in the art would understand that the described cutting systems may be used on any suitable sheath including embodiments of a sheath 100 having additional or alternative features to the elongate tube 120. The features and operations of the cutting systems described herein in relation to the sheath 100 may apply to the elongate tube 120 and / or to additional features of a sheath 100.

[0056] FIG. 5A illustrates an example cutting system 500. As shown in Figure 5A, the example cutting system is operating on a sheath 100 having a catheter or other medical device 115 extending therethrough. The medical device 115 may include, in some implementations, a dilator 110, medical device 300, or other medical device configured to be inserted into a natural cavity or lumen. In some embodiments, the example cutting system may operate on an elongate tube 120 of a sheath 100. An example cutting system 500 may include, but is not limited to, a housing 506, a shaft protection guide 502, a blade 512, and a feeding mechanism 508. The feed mechanism 508 can be configuredto rotate about an axis (for example, axis 602 as shown in FTGs. 6B and 7A). The housing 506 may include a channel 504 configured to accept the sheath 100 between at least a portion of the housing 506 and the shaft protection guide 502 that is coupled to the housing 506. The shaft protection guide 502 may be positioned in a lumen 121 of the sheath 100 between the catheter or other medical device 115 and an inner wall 125 of the sheath 100. The shaft protection guide 502 may be coupled to the blade 512.

[0057] As illustrated, a sheath cutting system 500 may include a protection guide 502 coupled to a blade 512 which is in turn coupled to the housing 506. Optionally, the protection guide 502 may be directly connected to the housing, for example by a narrow bridge element extending from the guide 502 to the housing 506 proximal of the cutting edge of the blade 512. The housing 506 may include a channel 504 which may be an at least partially enclosed lumen. In some examples, the channel 504 may be at least 50 percent enclosed and less than 100 percent enclosed. However, other percentages or amounts of enclosure are also possible, such as 60 percent, 70 percent, 80 percent, or 90 percent. The channel 504 may be adapted to accept the sheath 100 between the housing 506 and guide 502.

[0058] A feeding mechanism 508 may be configured to be coupled to the housing 506 by an axle 511. The feed mechanism may rotate about an axis colinear with the axle 511 (for example, axis 602 as shown in FIGs. 6B and 7 A) The feeding mechanism 508 may be configured to rotate and be aligned with the blade 512 and channel 504 so as to engage with the sheath 100 and pull the sheath 100 (such as the wall 125) into the blade 512 as the feeding mechanism 508 is rotated and / or while the cutting system 500 is operated. The feeding mechanism 508 may be connected or connectable to a rotary manipulator such as a lever or dial so as to cause the feeding mechanism 508 to rotate when the rotary manipulator is engaged. The feeding mechanism 508 may be manual, automated, or semiautomated. For example, the feeding mechanism 508 may be at least partially controlled using an electrically powered rotary manipulator (e.g., a motor) and / or controlled using a manually powered rotary manipulator. Further details of an example feeding mechanism are described herein with reference to, for example, FIGS. 6A-7B.

[0059] The sheath 100 may be coupled to or include an introducer handle or hub 522 wherein the lumen 121 of the sheath 100 continues and is coaxial with a lumen 524 in the introducer hub 522. The introducer hub 522 may include a hemostasis valve 526 or a plurality of hemostasis valves having various opening sizes. In the illustrated example, the introducer hub522 has a mating feature 520 adapted to releasably mate with a mating feature 516 on the housing 506. The mating features 520 and 516 may be locked and / or released by a locking actuator 518. The locking actuator 518 may or may not be integrated on the introducer hub 522 and / or housing 506. In some examples, the introducer hub 522 may be splittable or openable, such as by a handle and / or other opener that may or may not be part of the cutting system 500 and / or introducer hub 522.

[0060] An extended lumen containing a device 115 that may include a combination of the sheath lumen 121, the introducer hub lumen 524 and a partially closed lumen 514 of the protection guide 502 may have a minimum inner diameter (ID) that is larger than the maximum outer diameter (OD) of the device 115 that is configured to be advanced through the extended lumen. In an example where an introducer sheath 100 is an expandable introducer sheath, the sheath lumen 121 may elastically conform to the medical device 115 contained therein. In such an example, the extended lumen may be defined by the introducer hub lumen 524 and the partially closed lumen 514 of the protection guide, which may have a minimum ID that is larger than the maximum OD of the device 115, and the expandable sheath lumen 121, which may have an ID that can change in a range from X to Y, where X may be smaller than the ID of the introducer hub lumen 524 and / or the ID of the guide lumen 514, and Y may be greater than or equal to the ID of the introducer hub lumen 524 and / or the ID of the guide lumen 514. The cutting system 500 may be integrated with or provided with the introducer hub 522. In other examples, the cutting system 500 may be provided separately from the introducer hub 522.

[0061] In some examples, the cutting system 500 may be an auxiliary tool that is separate from an introducer hub 522, or it may be incorporated into the introducer hub 522, for example as part of an introducer handle, or stored in the handle. FIGS. 5B and 5C illustrate block diagrams of example orientations of example introducer handles 550 and 570 respectively and cutting systems 552, 572. The introducer hub 522 may be an introducer such as described above (for example, with reference to FIGS. 1-2). In the illustrated example of FIG. 5 A, the cutting system 500 is a separate tool configured to mate with the introducer hub 522. For example, the cutting system 500 may be configured to couple or mate with the introducer hub 522 via mating parts 516, 520 associated with the cutting system 500 and introducer hub 522 respectively. The mating features may be locked together by a locking system 518. When mated, the lumen 524 of the introducer hub 522 may be coaxial with a lumen 121 of the sheath 100.

[0062] As previously noted, an introducer handle may be separatable from the catheter contained in its lumen. In some embodiments the introducer handle is configured to be separated from the catheter using the cutting system 500 that is also used to cut the sheath 100. In such examples, the cutting system 500 may be multi-functional and in addition to having a means for cutting a braided or coiled sheath 100, it may have a feature for opening the introducer handle, such as a second blade. In some embodiments, the introducer handle is separatable with a different mechanism and / or the introducer sheath 100 is separatable from the cutting system 500. For example, the introducer handle may be separatable with a mechanism (e.g., a tear line, a cuttable strip, a screw cap, a snap fit) that allows parts of the handle to hinge open or pull apart, exposing an edge of the sheath 100 where the cutting system 500 can engage with the sheath 100. An example mechanism for separating the introducer handle from the introducer may include, but is not limited to, peel away mechanisms such as described with reference to Inti. Patent Publication No. PCT / US2021 / 071105, filed August 4, 2021, entitled INTRODUCER SHEATH HAVING AN ADJUSTABLE DIAMETER AND METHOD OF USE, which is incorporated by reference herein in its entirety.

[0063] FIG. 5B illustrates an example introducer hub or handle 550 with an integrated cutting system 552. For example, an introducer handle 550 may include a lumen 560 containing a catheter and an integrated cutting system 552 that may include, but is not limited to, a cutter 554 configured to cut an introducer sheath 562, a cutter 558 configured to open the introducer handle 550 (such as by, for example, a blade, a tear line, a cuttable strip, a screw cap, a snap fit, or other opening mechanism) and an actuator 556. The actuator 556 may be removable and may include a mechanism such as a lever or hand crank to reduce the bulk of the introducer when in use. The actuator 556 may be coupled to the cutting system 552 from the right or the left side to account for both right- and left- handedness. The integrated sheath cutter 554 may include some or all of the features described in various examples of cutting systems disclosed herein, such as described with reference to FIG. 5A and FIGS. 6A-7B.

[0064] FIG. 5C illustrates an example introducer hub or handle 570 that is separate and / or separable from a cutting system 572. For example, the introducer handle 570 may include a lumen 574 containing a catheter and a mating system 576 configured to mate with a mating system 580 of the cutting system 572. The cutting system 572 may include a sheath cutter 578 configured to cut or open an introducer sheath 562 that may include some or all of the featuresdescribed in various examples of cutting systems disclosed herein, such as described with reference to FIG. 5A and FIGS. 6A-7B. The cutting system 572 may optionally include or be coupled to an actuator 582 and / or handle 584. The actuator 582 and / or handle 584 may be removable in some examples. The handle 584 may be configured so that the user can hold the cutting system 572 by the handle 584 with one hand while moving the actuator 582 with respect to the handle with the other hand. The actuator 582 may thus act to engage the sheath cutter 578 to cut the introducer sheath 562. An introducer handle 570 may optionally include an integrated handle cutter, such as handle cutter 558 illustrated in FIG. 5B and / or may be configured to be opened in whole or in part by a secondary cutting system, which may or may not be part of the cutting system 572.

[0065] FIGS. 6A and 6B illustrate views of an example cutting tool where a shaft protection guide 604 is positioned in the lumen of the sheath 100 having a wall 125. The shaft protection guide 604 may be attached to a blade 606 having a sharp edge facing away from the shaft protection guide 604 and toward the inner wall 125 of the sheath 100 when the guide 604 is positioned in the lumen 121 of the sheath. As shown in FIG. 6B, the shaft protection guide 604 may have a C-shaped cross section with a partially formed lumen for sliding along the device 115 contained in the sheath 100. The partially formed lumen may have a longitudinal opening 608 that allows the catheter to be entered into and / or removed from the C-shaped lumen. The shaft protection guide 604 may have an approximately consistent wall thickness, which may be in a range of, for example, 0.2-0.5 mm. However, the wall thickness is not limited to this range.

[0066] An outer surface of the shaft protection guide 604 may be smooth. Advantageously, the smooth surface may facilitate gliding through the lumen of the sheath 100. In some examples, the outer surface may be made from or coated with a material with a low friction coefficient, such as PTFE. Alternatively, the outer surface or a portion of it may be ridged, which may help to facilitate holding of the sheath 100 in place as it is cut.

[0067] In some examples, such as illustrated in FIG. 6C, the shaft protection guide 604 may have an outer diameter (OD) that is tapered, wherein a distal end 610 that is intended to first enter the sheath 100 lumen has a first OD that is the most narrow (e.g., a wall thickness in a range of 0.2-0.5mm) and the OD increases toward a second OD at a proximal end 612 (or proximal OD). A tapered shaft protection guide 604 may help to stretch the sheath 100 or apply tension to the reinforcement filaments of the sheath 100 as the blade 606 is moved against them, which mayfacilitate cutting the sheath 100. In some examples, of a tapered shaft protection guide 604, an inner diameter (ID) of the shaft protection guide 604 may be consistent or approximately constant while the outer diameter (OD) is tapered. In examples where the cutting system 600 is designed for use with an expandable sheath 100 and thus, configured for the passage of a device 115 having a large or maximum OD, the proximal OD of the shaft protection guide 604 may be an amount that is equal to or slightly greater than said maximum OD of the device 115. Advantageously, this difference in diameter may help to stretch or apply tension to the wall 125 while cutting it.

[0068] Optionally, an outer surface 614 of the shaft protection guide 604 may include a sheath directing contour that directs cut portions of the sheath 100 away from the user’s hands or working area. For example, the sheath directing contour may be a flared contour that is at the proximal end 612 of the second OD of the shaft protection guide 604. Optionally, the cut portions of the sheath may be directed into a holding container.

[0069] With continued reference to FIGS. 6A-6C, the shaft protection guide 604 may be coupled to a blade 606. In some examples, the shaft protection guide 604 may be coupled to the blade 606 by plastic over molding. The blade 606 may be composed of a material at least as hard or harder than the wall 125 of the sheath 100 so as to facilitate cutting of the sheath 100. For example, the blade 606 may be a metal sheet. The blade 606 may be configured to extend into the C-shaped lumen to provide bond strength between the C-shaped lumen formed by the shaft protection guide 604 and the blade 606. In some examples, at least a portion of the blade 606 and at least a portion of the shaft protection guide 604 may be manufactured from one continuous metal sheet.

[0070] The blade 606 may be positioned with its sharp surface 622 angled with respect to the wall 125 to impart a slicing motion against the sheath 100. Alternatively or additionally, the blade 606 may be aligned tightly against teeth 620 of the feeding mechanism 616 to impart a shearing force on the sheath wall. In some examples, the blade 606 may be serrated. However, other cutting or sharp surface(s) 622 of the blade 606 are also possible, such as a flat surface.

[0071] The cutting system may include a feeding mechanism 616 configured to grab the sheath 100, for example by the wall 125 of the sheath, and move the sheath 100 towards and / or against the blade 606. In some examples, the feeding mechanism 616 includes a ratchet-like or cog-like wheel with teeth 620, such as illustrated in FIGS. 6 A and 6C. In some examples, the teeth 620 may be advantageously sized, shaped and / or spaced to operatively engage with reinforcementfilaments 618 in the sheath 100. The teeth 620 may align with gaps between filaments 618 and spacing between the teeth 620 may be sized to accept at least a portion of the filament 618. The teeth 620 may be angled, for example in the direction of rotation about an axis 602, which may improve engagement with the sheath. The teeth 620 may have a sharp edge.

[0072] In some embodiments, the feeding mechanism 616 may include a plurality of cog-like wheels 624 positioned at different radial directions around the central axis 602. For example, the feeding mechanism may have two wheels 624 positioned 180 degrees opposite one another. The cog-like wheel(s) 624 may have a flat disc shape, or alternatively may have a complex three dimensional shape. In one example, a cog has two rows of teeth with a groove between the two rows and the cutting blade is positioned in a portion of the groove, for example, as shown in FIG. 6B. In another example, the cog has two rows of teeth that are very close or touching one another at one location on the circumference of the wheel, and progressively spread apart from one another along the circumference. For example, each row of teeth may extend between a first end at a first position along the axis 602 and a second end at a second position along the axis 602, wherein the first position is closer to a center point of the cog-like wheel along the axis 602 than the second position. An example of this configuration is depicted in FIG. 7A. This configuration may allow the teeth to engage the filaments of the sheath and pull them apart from one another to stretch the sheath material or apply tension to the filaments as they are moved across the blade to improve cutting ability. In some embodiments, of this configuration, each row of teeth is arranged in a helical fashion along the cog-like wheel.

[0073] The feeding mechanism 616 may be turned about its axis of rotation 602 with a manual actuator, such as a crank lever or wings. The manual actuator may be geared to balance speed of rotation with cutting force. The manual actuator may be removable, such as when the cutting tool is integrated with the introducer handle (as discussed above with reference to FIG. 5B) so as to minimize bulk when the actuator is not needed. The cutting system 600 may have a cutting system handle (such as described with reference to FIG. 5C) that is rigidly connected to the shaft protection guide 604, blade 606, and / or feeding mechanism 616 so the user can hold the cutting system handle with one hand while moving the actuator with respect to the handle with the other hand. The feeding mechanism may have a ratcheting mechanism that allows it to be turned only in one direction. In cases where the feeding mechanism includes a plurality of cog-like wheels,such as described herein, the feeding mechanism may actuate more than one cog-like wheel connected by interleaving cog wheels to form a gear mechanism.

[0074] Alternatively, a feeding mechanism 616 may be electrically actuated with a switch that activates a motor. The motor might be connected to the rotation axis 602 by a gear. The electrically actuated feeding mechanism may be designed in a way that allows one-handed operation, freeing the other hand to stabilize the device shaft relative to the patient body.

[0075] FIGS. 7A and 7B illustrate views of an example cutting system 700 that may include an alternative feeding mechanism. One or more aspects of the system 700 may be the same or similar to other example cutting systems described herein, such as aspects of cutting systems 600 described with reference to FIGS. 6A-6C relating to the sheath protection guide 604 and / or blade 606. As illustrated in FIGS. 7A-7B, the cog-like wheel(s) 704 may have a three dimensional shape that improves engagement with the sheath surface. For example, the wheel’s axis of rotation 602 may be aligned perpendicular to the longitudinal axis of the sheath and the contour of the wheel in the direction of the axis of rotation may follow or approximate the cross sectional contour of the sheath, for example in its expanded state or unexpanded state. This may improve its ability to engage the sheath 100 and / or align the sheath 100 with the blade. The wheel 704 with a surface in a longitudinal section that approximates the surface of the sheath in its transverse section may optionally have teeth 706 arranged in various configurations as disclosed herein, such as a single row of teeth, two rows of teeth with groove between them, or two rows of teeth that are helically arranged on the wheel, for example in opposing directions.Example methods of using the cutting system

[0076] As described herein, the cutting system of FIGS. 5A-7B, can be used in methods for placing devices, such as MCS devices in patients. In some embodiments, for example, an expandable introducer sheath 100 can be delivered into a patient’s natural lumen (e.g., into a femoral, subclavian, axillary artery through an arteriotomy), for example using a commonly practiced Seidinger Technique. After the expandable introducer sheath 100 is delivered, a medical device (e.g., MCS device) 115 can be delivered through the expandable introducer sheath 100.

[0077] After the medical device is delivered through the introducer sheath 100, the sheath 100 can be removed while the medical device (e.g., MCS device) 115 remains in the patient and a shaft of the medical device remains passing through the patient’s natural lumen (e.g.,vasculature). For example, while holding the medical device shaft stationary with respect to the patient so the medical device 115 remains in a target location, the sheath cutting system can be operated as described herein (e.g., by engaging an actuator) so that the feeding mechanism 616 guides the wall 125 of the sheath 100 towards the cutting blade 606. After cutting, the sheath 100 can be removed in a radial direction.Terminology

[0078] While the above description provides examples of one or more processes or apparatuses, it will be appreciated that other processes or apparatuses may be within the scope of the accompanying claims.

[0079] Specific embodiments described herein are not intended to limit any claim and any claim may cover processes or apparatuses that differ from those described herein, unless specifically indicated otherwise. The claims are not limited to apparatuses or processes having all of the features of any one apparatus or process described herein or to features common to multiple or all of the apparatuses described herein, unless specifically indicated otherwise. It is possible that an apparatus or process described herein is not an embodiment of any exclusive right granted by issuance of this patent application. Any subject matter described herein and for which an exclusive right is not granted by issuance of this patent application may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicants, inventors or owners do not intend to abandon, disclaim or dedicate to the public any such subject matter by its disclosure in this document.

[0080] Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the claims, the principles and the novel features disclosed herein. The word “example” is used exclusively herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “example” is not necessarily to be construed as preferred or advantageous over other implementations, unless otherwise stated.

[0081] Certain features that arc described in this specification in the context of separate implementations also can be implemented in combination in a single implementation. Conversely,various features that are described in the context of a single implementation also can be implemented in multiple implementations separately or in any suitable sub-combination. Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination can be directed to a sub-combination or variation of a sub-combination.

[0082] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.

[0083] It will be understood by those within the art that, in general, terms used herein are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and / or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.”is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (c.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the ail would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

Claims

CLAIMSWHAT IS CLAIMED IS:

1. A system for opening a lumen of an introducer sheath of a cardiac assist system, the system comprising: an introducer sheath comprising a lumen configured to contain a medical device; a cutting system comprising: a blade configured to cut a wall of the introducer sheath; a protection guide configured be received between the medical device and the wall of the introducer sheath; and a feeding mechanism configured to guide the wall of the introducer sheath towards the blade.

2. The system of Claim 1, wherein the cutting system is configured to mate with an introducer hub.

3. The system of Claim 1 , wherein the cutting system is integrated into an introducer hub.

4. The system of any one of Claims 1-3, wherein the feeding mechanism comprises at least one cog-like wheel comprising a plurality of teeth.

5. The system of Claim 4, wherein the plurality of teeth are configured to engage one or more reinforcement filaments of the introducer sheath.

6. The system of any one of Claims 1-5, further comprising an actuator configured to actuate the feeding mechanism.

7. The system of Claim 6, wherein the actuator is configured to rotate the feeding mechanism about an axis transverse to the longitudinal axis of the introducer sheath.

8. The system of any one of Claims 6-7, wherein the actuator comprises a manual actuator geared to balance a speed of rotation of the feeding mechanism with a cutting force.

9. The system of any one of Claims 6-8, wherein the actuator comprises an electrical actuator.

10. The system of any one of Claims 1-9, wherein the protection guide comprises a partially closed lumen configured to receive the medical device.

11. The system of Claim 10, wherein the partially closed lumen is at least 50 percent closed.

12. The system of any one of Claims 1-11, wherein the protection guide comprises a C- shaped cross section.

13. The system of any one of Claims 1-12, wherein the protection guide and the blade are formed from a single material.

14. The system of any one of Claims 1-13, wherein the protection guide comprises an approximately constant outer diameter and an approximately constant inner diameter from a proximal end to a distal end of the protection guide.

15. The system of any one of Claims 1-13 , wherein the protection guide comprises an approximately constant inner diameter and a tapered outer diameter from a proximal end to a distal end of the protection guide, wherein the proximal end of the protection guide comprises a larger outer diameter than the distal end of the protection guide.

16. The system of Claim 15, wherein an outer surface of the protection guide is contoured to encourage a cut portion of the introducer sheath to move away from a longitudinal axis of the introducer sheath.

17. The system of any one of Claims 1-16, wherein an outer surface of the protection guide is smooth.

18. The system of any one of Claims 1-16, wherein an outer surface of the protection guide is at least partially ridged.

19. The system of any one of Claims 1-18, wherein the feeding mechanism comprises a wheel comprising a three-dimensional shape configured to at least partially follow a contour of the wall of the introducer sheath.

20. A method of delivering a catheter placed in a natural lumen of a patient, the method comprising: delivering an introducer sheath into the natural lumen of the patient; delivering a catheter through the introducer sheath; cutting the introducer sheath using a cutting system; and removing the introducer sheath from the catheter.

21. The method of claim 20, wherein the cutting system comprises a system according to any of claims 1-19.

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