Guide extension catheter

Abstract

A guide extension catheter (300) positionable within a guide catheter (302) and configured to receive an interventional device for insertion into the vasculature. The guide extension conduit includes a pushing member (322), a first reinforcing member (306) in contact with the pushing member, and a radially collapsible tubular membrane (310) in contact with the pushing member and the first reinforcing member. A tubular membrane is positioned distal to the first reinforcing member and radially collapses or wraps around the pushing member prior to receiving the interventional device. The urging member provides sufficient columnar strength to prevent longitudinal collapse of the tubular membrane during use. The guide extension catheter may access a target lesion in the vasculature and optionally provide a lower friction, larger diameter pathway (for a given compatible guide catheter size) through the target lesion in the vasculature, thereby reducing microscopic and macroscopic vasculature damage caused by delivery of the interventional device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority under 35 U.S.C. §119(c) to U.S. Provisional Application Serial No. 63 / 479,612, filed on January 12, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to devices, systems, and methods for interventional procedures, and more particularly, to a guide extension catheter for assisting in delivering an interventional device to a treatment site within a patient. Background Art

[0004] Generally, interventional procedures require the delivery of an interventional device via a guide catheter. Often, it is necessary to deliver the interventional device beyond the distal end of the guide catheter to the desired location, i.e., the target tissue region, in order to effectively administer the device. However, delivering the interventional device beyond the guide catheter requires high delivery forces and may cause micro- and / or macro-damage to the vasculature en route to the target tissue region. Summary of the Invention

[0005] The present inventors have recognized that there is a need to provide catheter delivery devices, systems, and methods that can be used to deliver interventional devices to a desired location while protecting the vasculature from abrasion or damage.

[0006] According to some embodiments, a guide extension catheter positionable within a guide catheter and configured to receive an interventional device for insertion into a vascular system may include a push member, a first reinforcement member in contact with the push member, and a radially collapsible tubular membrane in contact with the push member and the first reinforcement member. The tubular membrane may be positioned distal to the first reinforcement member and collapsed or wrapped around the push member prior to receiving the interventional device.

[0007] According to some embodiments, a guide extension catheter for use with a guide catheter may include a radially collapsible tubular membrane defining a lumen including a central axis and a pushing member that contacts the tubular membrane along its entire length and extends proximally of the tubular membrane for slidably positioning the tubular membrane within and partially beyond the distal end of the guide catheter. The tubular membrane may have no significant radial strength and may be configured to collapse radially inwardly toward the central axis. The tubular membrane may include a tensile strength sufficient to prevent tearing during insertion of an interventional cardiology device.

[0008] According to some embodiments, a method for accessing a coronary artery may include providing a guide catheter, advancing the guide catheter through a blood vessel to a position adjacent to the coronary artery ostium, and providing a guide extension catheter. The guide extension catheter may include a push member and a radially collapsible tubular membrane, the radially collapsible tubular membrane wrapped around the push member prior to receiving an interventional device. The method may also include advancing the guide extension catheter through the guide catheter to a position at which at least a portion of the tubular membrane extends distally beyond a distal end of the guide catheter and into the coronary artery, and advancing an interventional cardiology device through the guide catheter into a lumen defined by the tubular membrane, including causing the tubular membrane to expand from a collapsed, wrapped configuration to an expanded configuration.

[0009] These and other examples and features of the apparatus, system, and method of the present invention will be at least partially described in the following detailed description. This summary is intended to provide non-limiting examples of the subject matter of the present invention and is not intended to provide an exclusive or exhaustive explanation. The following detailed description is included to provide more information about the apparatus, system, and method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] This written disclosure describes non-limiting and non-exhaustive illustrative embodiments. Reference is made to the illustrative embodiments depicted in the accompanying drawings, in which:

[0011] Figure 1 A plan view of a guide catheter is shown having been advanced through the aorta to the coronary ostia, according to some embodiments.

[0012] Figure 2 Shown is a plan view of a guide extension catheter, as constructed in accordance with at least one embodiment, for use in conjunction with a guide catheter for delivering an interventional device into an occluded blood vessel for treatment.

[0013] Figure 3 An isometric view of a guide extension catheter and a guide catheter are shown with a fixed push member, according to some embodiments.

[0014] Figure 4 An isometric view of a guide catheter, a guide extension catheter, and a guidewire is shown, according to some embodiments.

[0015] Figure 5A An isometric view of a guide extension catheter with a first stiffening member is shown, according to some embodiments.

[0016] Figure 5B An isometric view of a guide extension catheter with a second stiffening member is shown, according to some embodiments.

[0017] Figure 6A A cross-sectional view of a tube member is shown, wherein a pushing member is disposed on an outer surface of the tube member, according to some embodiments.

[0018] Figure 6B A cross-sectional view of a tubular member is shown, wherein a pushing member is disposed on an inner surface of the tubular member, according to some embodiments.

[0019] Figure 6C A cross-sectional view of a tubular member is shown, wherein the pushing member is disposed in the plane of the tubular member, according to some embodiments.

[0020] Figure 6D A cross-sectional view of a tubular member and a guidewire is shown, wherein the pushing member is disposed within the plane of the tubular member, according to some embodiments.

[0021] Figure 7A Shown is a cross-sectional view of a radially collapsible tubular membrane in an expanded configuration, according to some embodiments.

[0022] Figure 7B A cross-sectional view illustrating a radially collapsible tubular film folding pattern according to some embodiments.

[0023] Figure 7C A cross-sectional view illustrating a radially collapsible tubular film folding pattern according to some embodiments.

[0024] Figure 7D A cross-sectional view illustrating a radially collapsible tubular film folding pattern according to some embodiments.

[0025] Figure 8A A plan view of an interventional device being advanced through a guide catheter and a guide extension catheter is shown, according to some embodiments.

[0026] Figure 8B A plan view of an interventional device being advanced through a guide catheter and a guide extension catheter is shown, according to some embodiments.

[0027] Figure 8C Shown is a plan view of an interventional device that has been advanced through a guide catheter and a guide extension catheter, according to some embodiments.

[0028] Figure 9A An isometric view of a guide extension catheter and a guide catheter are shown with a distal stiffening member, according to some embodiments.

[0029] Figure 9B According to some embodiments, Figure 9A An enlarged isometric view of the distal portion of the guide extension catheter is shown in FIG.

[0030] Figure 9CA side view of an interventional device according to some embodiments is shown, the interventional device being directed toward Figure 9A The configuration of the guide extension catheter shown in FIG. 1 is shown with the distal end proximally retracted.

[0031] Figure 9D A side view of an interventional device according to some embodiments is shown, the interventional device being directed toward Figure 9A The distal end of another configuration of the guide extension catheter shown in FIG. 1 is proximally retracted.

[0032] Figure 10A Isometric view of a guide extension catheter and a guide catheter showing a tubular member with a variable cross-sectional diameter, according to some embodiments.

[0033] Figure 10B According to some embodiments, Figure 10A 00140] Figure 1 is a front view of a first configuration of a portion of a tube member shown in FIG.

[0034] Figure 10C According to some embodiments, Figure 10A 0014] Figure 1 is a front view of a second configuration of a portion of a tube member shown in FIG.

[0035] Figure 11 An isometric view of a guide extension catheter and a guide catheter are shown with an expandable reinforcement member, according to some embodiments.

[0036] Figure 12A A schematic diagram illustrating column forces acting on a tubular member, according to some embodiments.

[0037] Figure 12B Schematic diagram illustrating bending forces acting on a tubular member, according to some embodiments.

[0038] Figure 12C Schematic diagram illustrating radial compressive forces acting on a tubular member, according to some embodiments.

[0039] Figure 12D Schematic diagram illustrating tension or expansion forces acting on a tubular member, according to some embodiments.

[0040] Figure 13 A flow chart illustrating a method for accessing a coronary artery and providing therapy to the artery, according to some embodiments. DETAILED DESCRIPTION

[0041] According to some embodiments, the present disclosure relates to a guide extension catheter having a push member, a reinforcement portion, and a radially collapsible tubular membrane having a lumen. The tubular membrane may have a minimum effective radial strength, a minimum effective cylindrical strength, and a minimum effective bending stiffness in compression. The tubular membrane may have sufficient tensile strength to avoid tearing during insertion of an interventional device and during removal of the interventional device from a patient. The tubular membrane may be permanently lubricated on an inner surface to facilitate advancement and withdrawal of the interventional device through its lumen, and may be permanently lubricated on an outer surface to enhance delivery of the guide extension catheter into a blood vessel.

[0042] According to some embodiments, the pushing member can serve as the backbone of the tubular membrane. The pushing member can optionally be in the form of a guide wire or a gradually tapering push rod to help manipulate and support the delivery of the guide extension catheter to the target tissue area. The reinforcing portion of the guide extension catheter can be disposed at the proximal end of the tubular membrane and can provide structural support to keep the proximal end of the lumen of the tubular membrane open and accessible. The guide extension catheter can also include a second reinforcing portion disposed at the distal end of the tubular membrane, the second reinforcing portion being configured to keep the distal end of the lumen of the tubular membrane open.

[0043] The devices, systems and methods herein generally relate to the delivery of medical devices via guide extension catheters, and more specifically, to devices, systems and methods for the enhanced and non-invasive delivery of interventional devices in patients undergoing percutaneous interventional procedures in order to (i) deliver interventional devices that would not be easily delivered with the aid of a selected in situ guide catheter alone, and / or (ii) reduce micro- and macro-arterial damage caused by the delivery of inflexible or non-lubricated interventional devices and existing guide extension catheters. It should be noted that although the following description is primarily directed to cardiovascular percutaneous interventional procedures, the devices, systems and methods described herein can be used in other medical specialties, for example, peripheral vasculature therapy, urology therapy, respiratory therapy, digestive therapy, diagnostic endoscopic therapy and / or any other medical treatment that can benefit from the use of a guide extension catheter.

[0044] Figure 1An exemplary minimally invasive cardiac intervention is shown that includes a guidewire 112 and a guide catheter 102. The guidewire 112 may include an elongated, smaller diameter member designed to navigate a blood vessel to a diseased site or vascular segment of interest. The guidewire may have various configurations, for example, including a stainless steel or nitinol core wire and / or a solid core wire wrapped in a smaller coil. The guide catheter 102 may include an elongated tubular member that defines a main lumen 104 along its length. The guide catheter 102 may be formed of, for example, polyurethane and may be shaped along its distal portion to facilitate advancement to and alignment with the coronary ostium 106 (or other area of ​​interest in the patient's body). Guide catheters 102 of various sizes, for example, 6F, 7F, or 8F guide catheters, may be inserted into the femoral artery or radial artery, where F is an abbreviation for French units (a unit of measurement for catheters) (a unit for measuring the diameter of a catheter (1F = 1 / 8 of a caliper). 1 / 3mm)), and the guide catheter is advanced through the aorta 108 to a position adjacent to the ostium 106 of the coronary artery 110.

[0045] A guidewire 112 (or a shorter, thicker introducer wire) and guide catheter 102 can be advanced through the arch 114 of the aorta 108 to the ostium 106. The guidewire 112 can then be advanced beyond the ostium 106 and into the coronary arteries 110. However, the diameter and rigidity of the distal end 116 of the guide catheter may not allow the device to be safely advanced beyond the ostium 106 and into the coronary arteries 110.

[0046] Maintaining the position of the distal end 116 of the guide catheter at the ostium 106 can facilitate successful access of the guidewire 112 or another interventional device to the diseased site (e.g., stenotic lesion 118). With the guide catheter 102 in its proper position, force can be applied to the proximal end of the guidewire to push the guidewire 112 to and beyond the lesion 118, and a treatment catheter (optionally comprising a balloon or stent) can be passed over the guidewire 112 to treat the site. Applying force to the guidewire 112 or treatment catheter can sometimes cause the guidewire 102 to dislodge from the ostium 106 of the coronary artery 110, and in such cases, the guidewire or treatment catheter must be advanced distally, independent of the guide catheter's ostium alignment and support, to reach the lesion 118. This can occur in the case of severe stenotic lesions 118 or tortuous anatomy, for example, where it is often difficult to pass the guidewire 112 or treatment catheter to and beyond the lesion. The intrinsic pulsation of the heart may also cause the distal end 116 of the guide catheter to lose its port position or otherwise become displaced such that it is no longer positioned to align and support the guidewire 112 or treatment catheter into the portion of the coronary artery 110 containing the lesion 118 .

[0047] If first in Figure 2 As shown in FIG, the guide extension catheter 200 of the present invention can improve access to and protect the coronary artery 210, the access extending all the way to and optionally beyond the stenotic lesion 218. The guide extension catheter 200 can include an elongated tubular member 220 and a pusher member 222, the total length of which is greater than the length of the guide catheter 202 (e.g., 130 cm to 175 cm or more). The outer diameter of the tubular member 220 can be sized to allow its distal end 224 to be inserted through the guide catheter 202 into the coronary artery 210 or its branch containing the lesion 218, thereby providing alignment, support, and a low-friction path for an interventional device (e.g., a treatment catheter) to extend beyond the distal end 216 of the guide catheter 202 to the lesion 218 and optionally through the lesion 218. The extension of the tubular member 220 into smaller arteries or branches can also be used to maintain the position of the guide catheter 202 at the arterial ostium 206 during surgery.

[0048] Pushing member 222 can be in the form of a guidewire or a tapered push rod, for example, to help steer and support the delivery of guide extension catheter 200 to lesion 218. Pushing member 222 can comprise stainless steel, nitinol, or another substantially rigid material and can be configured to be sufficiently rigid in terms of torque to prevent helical twisting of guide extension catheter 200 during use. For example, pushing member 222 can be flattened in cross-section along one or more portions of its length to help resist twisting and reduce the cross-profile of guide extension catheter 200.

[0049] Tubular member 220 may include a first reinforcement portion (not shown) disposed at its proximal end 226 and a second reinforcement portion disposed at its distal end 224. Tubular member 220 may also include a soft, flexible, radially collapsible tubular membrane 250 disposed distally of the first reinforcement portion and proximally of the second reinforcement portion.

[0050] In the absence of a guide extension catheter 200, delivery of an inflexible or non-lubricated interventional device through a segment of the coronary artery 210 distal to the guide catheter 202 can cause (i) endothelial damage (microscopic damage) and lead to atheroembolism and type 4 periprocedural myocardial infarction, and / or (ii) more severe macroscopic damage, including plaque rupture and coronary artery dissection, leading to acute / threatening ischemic complications, either of which can lead to atherosclerosis progression and ultimate target vessel failure. The soft, flexible, radially collapsible tubular membrane 250 can reduce device-artery interaction by providing a thin-walled structure that lines the artery and provides a lubricated intracoronary delivery path.

[0051] In some embodiments, the operating physician can apply a longitudinal force to the push member 222 to advance the distal portion 224 of the tubular member 220 over the guidewire 212 through the distal end 216 of the guide catheter and beyond the distal end 216 of the guide catheter and into the coronary artery 210 by directly or via a handle member 230 (e.g., the handle member 230 described in commonly owned U.S. Patent Publication No. 2019 / 0247619, the entire contents of which are incorporated herein by reference). The handle member 230 may include a flexible clip or clamp that is configured to attach to an external object when not in motion, as described in U.S. Patent Publication No. 2021 / 0008342, the entire contents of which are incorporated herein by reference. During the procedure, the proximal end portion 226 of the tubular member 220 can remain within the guide catheter 202. The physician can then advance the treatment catheter over the guidewire 212, through the main lumen 204 of the guide catheter 202, and through the lumen 228 of the tubular member 220 until the working portion of the treatment catheter is positioned beyond the distal end 224 of the tubular member. By using the tubular member 220, the physician can protect the vasculature from abrasion or damage caused by advancing the treatment catheter toward the lesion 218. Additionally, the tubular member 220 can provide additional alignment support for the guide catheter 202 relative to the coronary ostium as the treatment catheter is advanced.

[0052] Generally speaking, the size and shape of the lumen 228 (and therefore the tubular member 220) when expanded can be set to allow one or more interventional devices (e.g., a guidewire and a treatment catheter) to pass therethrough. The cross-sectional shape of the expanded lumen 228 can be similar to the cross-sectional shape of the main lumen 204 of the guide catheter. For example, in some examples, the cross-sectional shape of the expanded lumen 228 can be substantially uniform along its length. In other examples, the cross-sectional diameter can vary along the length of the tubular member 220. According to such an example embodiment, for example, the distal end 224 of the tubular member 220 can be narrower, for example, tapered, relative to the proximal end 226. In other examples, for example, the following combination Figure 10A In the examples described above, the proximal end of the tubular member can be narrower than the distal end. In such embodiments, the length of each differently sized portion of the tubular member 220 can also vary, and in some examples, the distal end 224 of the tubular member can be the longest. In examples including proximal and distal ends of different sizes, the difference in diameter between the proximal end 226 and the distal end 224 of the tubular member can be from about 1 French to about 4 French, or any value therebetween.

[0053] The outer diameter of tubular member 220, when expanded, can exhibit a maximum cross-sectional dimension that allows tubular member 220 to slide coaxially relative to guide catheter 202. In other embodiments, the outer cross-sectional dimension of tubular member 220, when expanded, can be less than the maximum allowable value. In various embodiments, the diameter of lumen 228 of tubular member 220, when expanded, is no more than approximately one French unit (a unit of catheter measurement) smaller than the diameter of lumen 204 of guide catheter 202. In one embodiment, guide extension catheter 200 can be manufactured in at least three sizes corresponding to the internal capacities of 8F, 7F, and 6F guide catheters commonly used in interventional cardiology procedures. The dimensional difference between the outer diameter of tubular member 220, when expanded, and the inner diameter of guide catheter 202 can vary. For example, the gap in cross-sectional diameter between the inner diameter of the guide catheter and the outer diameter of tubular member 220, when expanded, can be less than and / or approximately 0.001 inch, 0.002 inch, 0.003 inch, 0.004 inch, or 0.005 inch, or any distance therebetween. In certain embodiments, the cross-sectional diameter gap can be in the range of about 0.002 inches to 0.003 inches or about 0.002 inches to 0.0035 inches. For example, where the guide catheter has an inner diameter of 0.070 inches and the guide extension catheter has an expanded outer diameter of 0.068 inches, the gap would be 0.002 inches. In some embodiments, the diameter gap between the outer diameter of tubular member 220 when expanded and lumen 204 of guide catheter 202 can also be substantially continuous along a substantial portion of the length of tubular member 220 or a majority of the length of tubular member 220, or the diameter gap can increase along one or more distal portions of tubular member 220.

[0054] The length of tubular member 220 can be substantially less than the length of guide catheter 202; however, tubular member 220 can be designed to any length depending on the desired application, for example, about 6 cm to about 45 cm, about 10 cm to about 35 cm, about 14 cm to about 25 cm, or about 18 cm to about 20 cm.

[0055] Figure 3 An isometric view of guide extension catheter 300 is shown extending from distal end 304 of guide catheter 302. Guide extension catheter 300 includes a tubular member 320 having a proximal end 326 and a distal end 324. Figure 3 An embodiment, referred to herein as a "fixed wire," is shown in which a pushing member 322 is fixed to and extends distally from a tubular member 320. Pushing member 322 includes a distal tip 328.

[0056] Proximal end 326 of tubular member 320 may include first reinforcement member 306, which may comprise an elongated tube or concave rail configured to provide additional pushing strength during insertion of guide extension catheter 300 into a blood vessel and / or to maintain first lumen 308 of guide extension catheter 300. In other embodiments, first reinforcement member 306 may comprise a non-elongated tube, such as a tube or ring having an inner diameter greater than its length. First reinforcement member 306 may be a full or partial ring, for example, formed from a suitable polymer or metal, to maintain dilated entry / exit points, allowing for free advancement and withdrawal of guide extension catheter 300. In one embodiment, first reinforcement member 306 may comprise a polyether block amide having a durometer hardness of 72, such as PEBAX 7233 available from Arkema. PEBAX 7233 has a Shore D hardness of 61, a tensile strength at yield of 3770 psi, a tensile modulus of 74.0 ksi, and an elongation at yield of 18%. A lubricating layer of polytetrafluoroethylene (PTFE) can coat the inner surface of PEBAX 7233.

[0057] Tubular member 320 also includes a radially collapsible tubular membrane 310 located distally of first reinforcement member 306. A proximal end 312 of tubular membrane 310 can be secured to a distal end 307 of first reinforcement member 306, wherein first reinforcement member 306 is configured to maintain patency of lumen 314 of tubular membrane 310. In one embodiment, tubular membrane 310 can include a lubricating layer, a non-crosslinking adhesive layer, and a crosslinked heat shrink layer. The lubricating layer can include PTFE. The non-crosslinking adhesive layer can include a polyether block amide having a durometer hardness of 35, such as PEBAX 3533 available from Arkema. PEBAX 3533 has a Shore D hardness of 25, a tensile strength at break of 5660 psi, and a tensile modulus of 2.61 ksi to 2.76 ksi. The crosslinked heat shrink layer can include a polyether block amide having a durometer hardness of 55, such as PEBAX 5533 available from Arkema. PEBAX 5533 has a Shore D hardness of 50, a tensile strength at yield of 1740 psi and a tensile modulus of 23.9 ksi to 24.7 ksi.

[0058] In various embodiments, the tubular membrane 310 may have significantly less cylindrical strength, radial strength, and bending stiffness than those of the first reinforcement member 306 .

[0059] The cylindrical strength, radial strength, and bending stiffness of the tubular membrane 310 may be ineffective, i.e., the radially collapsible tubular membrane 310 may have no effective cylindrical strength, no effective radial strength, and no effective bending stiffness. In other words, any radial force, cylindrical force, or bending force may cause the tubular membrane 310 to deflect, collapse, and / or bend, and the tubular membrane 310 will not provide effective resistance to the radial force, cylindrical force, or bending force.

[0060] The tubular film 310 can have sufficient tensile strength to prevent tearing of its wall during advancement and withdrawal of the interventional device. For example, during advancement of the interventional device through the tubular film 310, the interventional device can provide a force that pushes radially outward against the wall of the tubular film 310. The tubular film 310 can have sufficient tensile strength to withstand the radially outward force of the interventional device so that the interventional device does not tear or otherwise damage the wall of the tubular film 310.

[0061] The tubular membrane 310 can be permanently lubricated on one or both of its inner and outer surfaces via a hydrophobic silicone or polymer coating. The lubricated inner surface of the tubular membrane 310 can be configured to reduce friction between the tubular membrane 310 and the interventional device during insertion and / or withdrawal of the device. The lubricated outer surface of the tubular membrane 310 can be configured to reduce friction between the tubular membrane 310 and the guide catheter 302 during insertion and / or withdrawal of the guide extension catheter 300 from the guide catheter 302.

[0062] Figure 3 The lumen 314 of the tubular membrane 310 is shown in a fully open / fully expanded state. In the fully open state, the lumen 314 of the tubular membrane 310 has a first inner diameter, a first outer diameter, and a first cross-sectional area. The tubular membrane 310 comprises a wall thickness of 0.00075 inches to 0.004 inches and an outer diameter to wall thickness ratio of 10:1 to 200:1, or optionally comprises an outer diameter to wall thickness ratio of 10:1 to 50:1, for example, 18:1, 24:1, 30:1, 36:1, 42:1, and ranges therebetween. The thin-walled nature of the tubular membrane 310, and thus the larger cross-sectional area for a given compatible guide catheter size, allows interventionalists to perform a wider range of challenging procedures in today's complex world of interventions via either the traditional femoral approach or the new-age radial approach.

[0063] In some embodiments, the lumen 314 of the tubular membrane 310 can be freely collapsible, i.e., the tubular membrane 310 cannot support the first cross-sectional area without external support (e.g., the first reinforcing member 306 supports the patency of the lumen 314) or without internal support (e.g., an interventional device inserted through the tubular membrane opens the lumen via internal forces). Thus, if the tubular membrane 314 is not supported by additional components or features, the lumen 314 will "collapse," meaning that the cross-sectional area of ​​the lumen 314 will be smaller than the first cross-sectional area (i.e., the cross-sectional area of ​​the lumen 314 will be smaller than the first cross-sectional area). Figure 3 cross-sectional area in the fully opened state shown in ).

[0064] In the collapsed state, the tubular membrane 310 does not exhibit significant tensile strength, i.e., when the cross-sectional area of ​​the lumen 314 is smaller than in the fully open state, the tubular membrane 310 will not provide significant tensile resistance. However, in the fully open state, the tubular membrane 310 can exhibit a tensile strength sufficient to prevent tearing of the wall of the tubular membrane 310 and to prevent micro- and / or macro-damage to the vessel wall during insertion of an interventional device. In other words, when the cross-sectional area of ​​the tubular membrane 310 is expanded to the fully open state, the tubular membrane 310 will provide resistance to any radially outward tensile forces. In various embodiments, the tubular membrane can have a tensile strength exceeding approximately 2.25 pounds.

[0065] exist Figure 3 In the embodiment shown in , the pushing member 322 extends distally from the distal end 324 of the tubular member 320. The pushing member 322 may include a stainless steel or nitinol core wire and / or a solid core wire wrapped in a smaller coil. The distal tip 328 of the pushing member 322 may include a non-invasive guidewire-like distal tip. In some embodiments, the non-invasive guidewire-like distal tip includes a tapered core surrounded by a coil, and in some embodiments, the non-invasive guidewire-like distal tip includes a steerable tip. The pushing member 322 can serve as the backbone of the tubular membrane 310, that is, the pushing member 322 can provide columnar strength and / or bending stiffness to facilitate the advancement and withdrawal of the guide extension catheter 300. In some embodiments, the proximal portion of the pushing member 322 may include a removable support member or be surrounded by a removable support member, the removable support member being as described in commonly owned U.S. Patent No. 10,953,197, the entire contents of which are incorporated herein by reference.

[0066] Figure 4An isometric view of a guide extension catheter 300' and a guidewire 450 is shown, according to some embodiments. The guide extension catheter 300' is referred to herein as a "rapid exchange" embodiment, in which the pusher member 322' terminates at or before the distal end 324 of the tubular member 320, and the guidewire 450 extends distally beyond the distal end 324 to guide the guide extension catheter 300' and / or an interventional device. The guidewire 450 can be slidable relative to the tubular member 320, or more specifically, the tubular member 320 can be slid over the guidewire 450 and advanced into position adjacent to the target area.

[0067] The slidable nature of the guidewire 450 relative to the guide extension catheter 300' enables rapid exchange of interventional devices. For example, an interventional device, such as a balloon dilator (not shown), can be slidably advanced over the guidewire 450. The balloon dilator can be advanced through the guide catheter 302 and the guide extension catheter 300' and advanced distally from the distal end 324 of the tubular member 320 to the target tissue. Treatment can be provided at the target tissue (e.g., the balloon dilator can be inflated to open a vascular lesion), and the balloon dilator can be slidably retracted from the target tissue over the guidewire 450 through the guide extension catheter 300' and the guide catheter 302. The balloon dilator can be withdrawn from the patient and removed from the guidewire 450. A second interventional device, such as a stent, can then be slidably received over the guidewire 450 and advanced through the guide catheter 302, through the guide extension catheter 300', to the target tissue located distal to the distal end 324 of the tubular member 320. A second treatment can be provided at the target tissue (e.g., a stent can be deployed). Thus, guidewire 450 enables rapid exchange of interventional devices.

[0068] In some embodiments, the pushing member 322' can terminate in the second reinforcing member 334 of the guide extension catheter 300'. The pushing member 322' can be directly fixed to the second reinforcing member 334, wherein the pushing member 322' is configured to provide additional pushing strength during the insertion of the guide extension catheter 300 into the blood vessel and the second reinforcing element 334 is configured to maintain the lumen 314 of the tubular membrane 310. The second reinforcing member 334 can be sufficiently flexible and deflectable along the axis of the guide extension catheter 300' so that when encountering resistance to advancement, the second reinforcing member 334 conforms to create a reduced cross profile. The second reinforcing member 334 can be retracted and deployed outside the guide catheter. For example, a hollow guidewire or pushing member 322' can allow for a second reinforcing member 334 in the form of a retractable distal reinforcing ring.

[0069] Figure 5AAn isometric view of a guide extension catheter 300 is shown, showing a first reinforcement member 306. The proximal end 330 of the first reinforcement member 306 may include a concave opening 332 leading to the first lumen 308. The concave opening 332 can be configured to easily insert a guidewire (not shown) or an interventional device (not shown) into the first lumen 308 of the first reinforcement member 306. For example, the concave opening 332 can provide a larger area than the area associated with the opening oriented perpendicular to the longitudinal axis of the tubular member to receive the interventional device into the tubular member. In some embodiments, the first reinforcement member 306 may include an extended concave track that defines a semi-tubular feature that is configured to help guide the interventional device into the first lumen 308 of the first reinforcement member 306. Exemplary embodiments of semi-tubes, concave tracks, and other first reinforcement members and features are described in commonly owned U.S. Patent Publication No. 2019 / 0247619, the entire contents of which are incorporated herein by reference.

[0070] The first reinforcement member 306 can have a length l defined between a proximal end 330 and a distal end 307. The first reinforcement member 306 can have an inner diameter d i (also known as the first lumen diameter), outer diameter d o In some embodiments, the length l of the first reinforcing member can be as small as d i / 10.

[0071] In some embodiments, the first reinforcement member 306 can be formed by a polymer inner layer, a polymer outer layer and / or a reinforcement layer (e.g., a braid or coil) disposed between or near the polymer layers. According to such an example, the polymer inner layer can be composed of or coated with silicone, PTFE, or another lubricating material to provide a smooth surface for the received interventional device. The polymer outer layer can include one or more materials, such as polyurethane, polyethylene, polyolefin, or polyether block amide, whose durometer hardness decreases successively along the length of the tubular member and can be coated with a material that reduces friction (e.g., a hydrophilic material) to facilitate insertion and traceability through the vascular system and guide catheter. In embodiments featuring a braid or coil, the reinforcement braid or coil can be formed of, for example, stainless steel or a platinum alloy and can extend between the polymer layers along at least a portion of the length of the tubular member.

[0072] In some embodiments, the push member 322 can include one or more depth markers that can be positioned at predetermined lengths relative to the distal end of the tubular member 320. One or more radiopaque marker bands can be positioned on the tubular member 320. The marker bands can be composed of tungsten, platinum, or alloys thereof and can have a metal band structure. Alternatively, for space-saving reasons, the marker bands can be formed by impregnating portions of the tubular member 320 with a radiopaque filler material (e.g., barium sulfate, bismuth trioxide, bismuth carbonate, powdered tungsten, powdered tantalum, etc.).

[0073] Figure 5B The tubular member 320 is shown including a second reinforcing member 334 disposed at the distal end 324 of the tubular member 320. The second reinforcing member 334 can be configured to maintain patency of the lumen 314 at the distal end 324 of the tubular membrane 310, such that the interventional device can be withdrawn from the lesion area into the lumen 314 of the guide extension catheter 300. In some embodiments, the second reinforcing member 334 can be configured to selectively open and / or close the distal end 324 of the tubular membrane 310.

[0074] In some embodiments, the second stiffening member can include a small diameter snare-like device extending from the hollow push member 322, such as the snare device described in commonly owned US Patent Publication No. 2005 / 0234474, the entire contents of which are incorporated herein by reference.

[0075] like Figures 5A to 5B As shown in FIG, the pushing member 322 may be fixed to the inner surface of the tube member 320 (see also FIG. Figure 6B ). In other embodiments, for example, Figure 6A and Figures 6C to 6D , the pushing member 332 may be fixed to the outer surface of the tube member 320 (see, for example, Figure 6A ) or integrated within the wall of the tubular member 320, for example, sandwiched between an inner polymer layer and an outer polymer layer (see, for example, Figures 6C to 6D ). The position of the pushing member 322 can be configured to maximize the first lumen area, i.e., maximize the cross-sectional area within the lumen of the first reinforcement member 306, to allow for delivery of larger interventional devices through the guide catheter. In other embodiments, the position of the pushing member 322 can be configured to minimize the outer diameter, i.e., to allow for delivery of the guide extension catheter 300 through the guide catheter 302. In further embodiments, the position of the pushing member 322 can be configured to control the flexibility, maneuverability, and / or deflection of the guide extension catheter 300.

[0076] like 6A to 6DAs shown in , the pushing member 322 can define a circular cross-section along a portion of its length. However, the cross-sectional shape and size of the pushing member 322 can vary. For example, the pushing member 322 can include an arcuate or flat sheet-like cross-sectional shape, and rectangular, irregular, oblong, and elliptical cross-sectional shapes are also within the scope of the present disclosure. An exemplary embodiment of a pushing member is described in co-owned U.S. Patent Publication No. 10,751,514, the entire contents of which are incorporated herein by reference. The stiffness of the pushing member 322 can be uniform or substantially uniform along its length, or a region having variable stiffness along its length can be defined. For example, the pushing member 322 can be softer near its distal end than near its proximal end. The pushing member 322 can include sufficient rigidity to avoid spiral twisting of the guide extension catheter 300 during use.

[0077] Figure 6D A cross-sectional view of a tubular member 320 is shown having a push member 322 integrated into the wall and a guide wire 450 extending therethrough. The guide wire 450 may be slidable relative to the tubular member 320, i.e., the guide wire 450 may slide in a longitudinal direction relative to the longitudinal axis of the tubular member 320. In some embodiments, the guide wire 450 may also be able to travel laterally and vertically within the tubular member (e.g., the guide wire 450 may be able to move around the inner circumference of the tubular member 320 or near the center point of the tubular member 320).

[0078] As described above, the tubular film 310 may be freely collapsible and / or may not exhibit significant columnar strength, radial strength, or bending stiffness. Therefore, the tubular film 310 may be loosely draped over the pushing members 322, 322' and / or the guidewire 450 prior to insertion into the patient. In some embodiments, the tubular film 310 may be folded around the pushing members 322, 322' to reduce cross-sectional area and / or reduce friction during insertion. 7A to 7D A cross-sectional view of an exemplary fold of the tubular membrane 310 guiding the extension catheter 300 is shown. The pushing member 322 is disposed near the center of the tubular membrane, however, in other embodiments, the pushing member 322 may be offset from the center of the tubular membrane, fixed to the inner wall, the outer wall, or integrated into the wall of the tubular membrane 310 (e.g., see 6A to 6D ).

[0079] exist 7A to 7DIn the embodiment shown in , the tubular membrane 310 is shaped to include one or more folding flaps 740, which in this case are four folding flaps 740. The one or more folding flaps 740 rotate about the pushing member 322 to reduce the cross-sectional profile of the guide extension catheter 300. In some embodiments, the one or more folding flaps 740 may include a variety of different folding geometries and sizes. The folding flaps 740 may be configured to open or unfold when an interventional device is inserted through the tubular membrane 310. For example, when an interventional device is inserted through the folded tubular membrane 310, the interventional device may provide a radially outward force on the tubular membrane 310 to push the wall radially outward, and thereby the folding flaps 740 are pushed outward and unfolded. In Figures 8A to 8C A diagram showing the unfolding and / or opening of a tubular membrane is shown in FIG.

[0080] Figures 8A to 8C An exemplary progression of an interventional device 850 being inserted through a guide extension catheter 300 is shown. In some embodiments, a guide wire 450 can be positioned within the patient prior to inserting the guide extension catheter 300 and the interventional device 850, and the guide wire 450 can be configured to guide the guide extension catheter 300 into the correct position. In this way, the guide extension catheter 300 can slide over the guide wire 450 and follow the guide wire 450 to a position adjacent to the target tissue area. The guide extension catheter 300 can also be inserted via the guide catheter 302 (in Figures 8A to 8C The guide extension catheter 300 can be slidably advanced toward the target tissue area by applying force to the pushing member 322. In some embodiments, a delivery assist device (e.g., a device described in commonly owned U.S. Patent Publication No. 8,048,032, the entire contents of which are incorporated herein by reference) can be used to assist in opening the lumen 314 of the tubular membrane 310.

[0081] The interventional device 850 may be slidably secured to the guidewire 450 for longitudinal movement along the length of the guidewire 450. Figure 8A , the interventional device enters the first reinforcing member 306 of the tubular member 320. The first reinforcing member can be configured to maintain the patency of the first lumen 308 of the tubular member 320 so that the interventional device 850 can be easily inserted into the tubular member 320. The first reinforcing member 306 can be configured to maintain the patency of the lumen 314 of the tubular membrane 310 at the proximal end 312 of the tubular membrane 310. In some embodiments, before inserting the interventional device 850 (e.g., see 7A to 7D ), the tubular membrane 310 can be folded along a substantial portion of its length. In some embodiments, the tubular membrane 310 can be freely collapsed, i.e., the cross-sectional area of ​​the lumen 314 is smaller than that in the fully open state (e.g., see Figure 3 ).

[0082] like Figure 8B As shown in FIG, the interventional device 850 can be advanced distally of the first reinforcement portion 306 and into the tubular membrane 310. As the interventional device 850 is advanced through the tubular membrane 310, the lumen 314 of the tubular membrane 310 can be opened. For example, in embodiments where the tubular membrane 310 is folded along a substantial portion of its length (e.g., see 7A to 7D ), advancement of the interventional device 850 can expand the tubular membrane 310 and push the walls of the tubular membrane 310 radially outward, thereby increasing the cross-sectional area of ​​the lumen 314. In embodiments where the tubular membrane 310 is freely collapsed prior to insertion of the interventional device, the lumen 314 of the tubular membrane 310 can be pushed open as the interventional device 850 is advanced through the tubular membrane 310.

[0083] like Figure 8C As shown in FIG, the interventional device can be advanced distally of the distal end 324 of the tubular member 320 to deliver treatment at or near the target tissue location. In some embodiments, the tubular member 320 may include a second reinforcing member 334 disposed at the distal end 324 of the tubular member 320. The second reinforcing member 334 (at Figures 8A to 8C The second reinforcing member 334 (not shown) can be configured to maintain the lumen 314 of the tubular membrane 310 at the distal end 324 so that the interventional device 850 can be withdrawn from the target tissue area into the tubular member 320 without hindrance. For example, if the distal end 324 of the tubular member 320 collapses or folds, the lumen 314 may be smaller than the cross-sectional dimensions of the interventional device 850, causing the wall of the tubular membrane 310 to twist, kink, or fold when the interventional device 850 is withdrawn. The second reinforcing member 334 may include a tube or a ring having a cylindrical strength, radial strength, and / or bending stiffness that is greater than the corresponding cylindrical strength, radial strength, and / or bending stiffness of the tubular membrane 310.

[0084] Figure 9AAn isometric view of a guide extension catheter featuring a distal reinforcement member configured to pivot, tilt, tilt, or otherwise undergo a change in angular position upon contact with a proximally retracted interventional device to open a passageway for the proximally retracted interventional device defined by the lumen of the tubular member. As shown extending from the distal end 504 of a guide catheter 502, the guide extension catheter 500 includes a tubular member 520 having a distal end 524, a proximal end 526, and a radially collapsible tubular membrane 510 to which a pusher member 522 is secured. A guidewire 528 extends through the lumen 514 of the tubular membrane 510, which is depicted as being in a fully open / fully expanded state, through the distal end 524 of the tubular member 520 and distally beyond the distal end 524 of the tubular member 520. The tubular film 510 may be freely collapsible and / or foldable consistent with the embodiments of tubular films described herein.

[0085] The proximal end 526 of the tubular member 520 may include a first reinforcement member 506, which may include a substantially circular component, such as a ring or coil. Embodiments of the reinforcement member 506 may also include or comprise features similar or identical to those of the reinforcement member 306, such as an elongated tube, a concave track, a non-elongated tube (e.g., a partial or complete ring or coil), or a combination thereof. Embodiments of the first reinforcement member 506 may include a variety of materials, non-limiting examples of which may include one or more metals, plastics, or a combination thereof.

[0086] As in Figure 9A As further shown in FIG, the distal end 524 of the tubular member 520 may include a second distal reinforcement member 534 comprising a resilient support ring or coil member (hereinafter referred to as "coil member 534") that is attached to the distal end of the tubular membrane 510 and is configured to facilitate entry of one or more interventional devices (e.g., a treatment catheter) into the tubular member 520 during proximal withdrawal of such devices from a target site within the vasculature of a subject. The coil member 534 may include a flexible, deformable shape memory material and / or an elastic configuration that is biased toward a resting, unconstrained configuration in which the coil member 534 is substantially perpendicular or otherwise orthogonal to the longitudinal axis of the push member 522, as shown. Figure 9A. The unconstrained configuration of coil member 534 can establish, expand, and / or maintain patency of at least a distal portion of lumen 514 of tubular membrane 510. In its resting state, coil member 534 is not positioned within a guide catheter or constrained within an operative space within the vasculature of a subject, and thus coil member 534 can define a distal opening into tubular member 520 that is oriented and sized for unobstructed passage of one or more interventional devices therein.

[0087] When the coil member 534 is restrained within a blood vessel during an interventional procedure, the coil member 534 may tilt, bend, or otherwise bend in a proximal or distal direction, such as by Figure 9B 524. In this configuration, and when no interventional device is positioned within the tubular membrane 510, the membrane 510 can be in its collapsed state, loosely covering or folded over the push member 522, which in some examples may not be particularly conducive to the backing of an interventional device into it from beyond its distal end due to the potential risk of the membrane interfering with the path of the interventional device. To facilitate the entry of the interventional device 538 proximally withdrawn toward the distal end 524 of the tubular member 520 (in Figure 9C and Figure 9D ), contact of the interventional device 538 with the leading edge or distal-most portion 535a, 535b of the angled coil member 534 causes the coil member 534 to swing or pivot toward its unconstrained configuration substantially perpendicular or orthogonal to the longitudinal axis of the push member 522, thereby transitioning the distal end of the lumen 514 of the tubular membrane 510 to its expanded, non-collapsed state and opening a clear passage through the opening defined by the coil member 534 into the tubular member 520 through which the interventional device can be proximally retracted. Thus, the angle of the coil member 534 relative to the longitudinal axis of the push member 522 can change in response to the force applied by the interventional device. Due to its material composition and configuration, the angle and / or cross-sectional form of the coil member 534 can also change in response to changes in the subject's vasculature (e.g., widening and narrowing of a tortuous blood vessel).

[0088] In embodiments featuring a coil member 534, the coil member 534 tilts proximally when the coil member 534 is restrained within the guide catheter 502 and / or within the blood vessel (see FIG. Figure 9C ), contact between the distal-most portion 535a of the coil member 534 and the proximally retracted interventional device 538 causes the opposite "free" end 536a of the coil member 534 to be released. Figure 9C, the coil member 534 pivots or swings toward its resting, unconstrained configuration in the direction of the curved arrow shown in the figure, causing the attached distal end of the tubular membrane 510 to pivot or swing therewith. Figure 9D contact between the distal-most portion 535b of the coil member 534 (which constitutes the "free" end in this configuration) and the proximally retracted interventional device 538 causes the distal-most portion 535b of the coil member 534 to be retracted. Figure 9D , toward its resting, unconstrained configuration, again causing the attached distal end of tubular membrane 510 to pivot or rock with it. Thus, proximal retraction of the interventional device causes coil member 534 to return to or near its resting, unconstrained state, in which the cross-sectional area of ​​lumen 514 of at least the distal portion of tubular member 510 is increased or maximized, and the likelihood of interference with the proximally retracted interventional device, along with any associated damage to tubular membrane 510, is reduced. Thus, the angle of coil member 534 can directly respond to the position and movement of interventional device 538 and the size and curvature of the surrounding vessel wall.

[0089] Embodiments of the coil member 534 can be integrally formed with the push member 522 such that the coil member 534 can be continuous with the push member 522 and, in some examples, can define the distal end of the push member 522. According to such embodiments, the push member 522 can include an elongated push rod or body having a longitudinal axis substantially aligned with the longitudinal axis of the tubular member 520 and the guide catheter 502 and a distal portion that is coiled, curled, or otherwise bent away from its longitudinal axis. In other embodiments, the coil member 534 can include different components, portions, or sections that are fixed, coupled, or otherwise attached to the distal end of the push member 522, for example, via welding.

[0090] Figure 10AAn isometric view of a guide extension catheter is provided, which is configured to receive a proximally retracted interventional device via a tubular member having a varying cross-sectional area along its length. As shown, the guide extension catheter 600 includes a tubular member 620 having a distal end 624, a proximal end 626, and a radially collapsible tubular membrane 610 to which a pusher member 622 is affixed. A guidewire can extend through a lumen 614 of the tubular membrane 610, extending through the distal end 624 of the tubular member 620 and distally beyond the distal end 624 of the tubular member 620. The lumen 614 of the tubular membrane 610 is depicted as being in a fully open / fully expanded state. In the illustrated example, the radially collapsible tubular membrane 610 is tapered so that in the expanded state, the cross-sectional area of ​​the distal end 624 of the tubular member 620 is greater than the cross-sectional area of ​​the proximal end 626 of the tubular member 620. The proximal end 626 of the tubular member 620 can include a first reinforcement member 606 , which can be similar or substantially identical to reinforcement members 306 and / or 506 .

[0091] The distal portion 624 of the tubular member 620 may include or be defined by a distal reinforcing member 634 attached to the distal end of the tubular membrane 610. The distal reinforcing member 634 may include a flexible shape memory material and / or an elastic configuration that is configured to bend radially outward into an expanded state when advanced distally beyond the distal end 604 of the guide catheter 602. Embodiments of the distal reinforcing member 634 may include an elastic circular element, such as a ring or coil, that may be deformable and configured to be angularly adjusted relative to the longitudinal axis of the push member 622, just like the coil member 534. In the expanded configuration, the tubular member 620 may assume a conical or funnel shape, wherein the diameter of the tubular member 620, and thus the cross-sectional area of ​​the tubular member 620, is greatest at its distal end 624. Radial expansion or flexing of the distal reinforcement member 634 and thereby the concomitant widening of at least the distal portion of the lumen 614 of the tubular membrane 610 to which it is attached can occur automatically in a spring-like manner upon its release from the guide catheter 602, thereby opening or expanding the cross-sectional space available for entry and smooth passage of an interventional device through the distal end 624, for example during an interventional procedure or during proximal retraction of such a device upon completion of the interventional procedure.

[0092] Together with the self-expandable, flexible configuration of distal reinforcement member 634, this distal expansion of tubular member 620 is enabled by the relatively narrow cross-sectional wall thickness and relatively small cross-sectional space occupied by radially collapsible tubular membrane 610 in its collapsed state. The compactness of tubular membrane 610 in its collapsed configuration allows tubular member 620 to be configured for advancement through a guide catheter 602 having a smaller inner diameter relative to at least a portion of the inner and / or outer diameters of tubular member 620 in its expanded state. Thus, the cross-sectional diameter of tubular member 620 along at least a distal portion thereof in its expanded state is not limited by the inner diameter of guide catheter 602. Consequently, guide extension catheter 600 is compatible with a wider range of interventional devices than existing guide extension devices and can be adapted to simultaneously pass more than one interventional device during a given procedure, thereby enhancing the ease of performing a wide range of interventional procedures.

[0093] In the expanded state, the cross-sectional dimensions of the tubular member 620 along its length can vary. In some examples, after the tubular member 620 is advanced beyond the distal end 604 of the guide catheter 602, at least the distal portion of the tubular member 620 (e.g., having a diameter B) can expand until its outer periphery abuts the inner surface of the surrounding vessel wall. In such embodiments, at least a portion of the tubular member 620 in the expanded state can have an outer diameter that is greater than or approximately equal to the inner diameter of the guide catheter 602. Different sizes of guide catheters 602 can be used, for example, 6F, 7F, or 8F, and the diameter variation between the proximal end 626 and the distal end 624 of the tubular member 620 can vary from about 1F to about 4F, or any value therebetween. In its expanded state, the size of the cross-sectional gap between the inner diameter of the guide catheter 602 and the outer diameter of the tubular member 620 can also vary along at least a portion of its length. For example, when the tubular member 620 extends beyond the distal end 604 of the guide catheter 602, the gap between the inner diameter of the guide catheter 602 and the larger outer diameter of at least a portion of the tubular member 620 can be greater than, less than and / or equal to approximately 0.001 inches, 0.002 inches, 0.003 inches, 0.004 inches, 0.005 inches, 0.006 inches, 0.007 inches, 0.008 inches, 0.009 inches, 0.010 inches, 0.011 inches, 0.012 inches, 0.013 inches, 0.014 inches, 0.015 inches, or any value therebetween.

[0094] The cross-sectional diameter, and thus the area, of the tubular member 620 extending beyond the distal end 604 of the guide catheter 602 can increase in a smooth, gradient manner, such that the resulting conical configuration defines a constant or substantially constant slope. In other embodiments, the expanded tubular member 620 can define one or more discrete segments or steps, thereby defining different slopes. Thus, the cross-sectional area of ​​the expanded tubular member 620 can increase in a smooth or stepped manner in the distal direction.

[0095] The proximal end 626 of the tubular member 620 that remains nested within the guide catheter 602 can have a maximum cross-sectional dimension that allows the tubular member 620 to slide coaxially relative to the guide catheter 602. In other embodiments, the outer diameter of at least the proximal portion of the tubular member 620 can be less than the maximum allowable value. In various embodiments, the diameter (e.g., diameter A) of the first lumen 608 of the tubular member 620 positioned within the guide catheter 602 can be no more than about one French unit (a unit of measurement for catheters) smaller than the inner diameter of the lumen of the guide catheter 602. In one embodiment, the guide extension catheter 600 can be made in at least three sizes that correspond to the internal capacity of 8F, 7F, and 6F guide catheters commonly used in interventional cardiology procedures. The size difference between the outer diameter of at least the proximal portion 626 of the tubular member 620 and the inner diameter of the guide catheter 602 can vary. For example, the gap in cross-sectional diameter between the inner diameter of the guide catheter 602 and the maximum outer diameter of at least the proximal portion 626 of the tubular member 620, for example, at the proximal reinforcement member 606, can be less than and / or equal to approximately 0.001 inches, 0.002 inches, 0.003 inches, 0.004 inches, or 0.005 inches, or any distance value therebetween. In specific embodiments, the cross-sectional diameter gap can be in the range of approximately 0.002 inches to 0.003 inches, or approximately 0.002 to 0.0035 inches. In some embodiments, the diametrical gap between the maximum outer diameter of at least the proximal portion of the tubular member 620 and the lumen of the guide catheter 602 can also be substantially continuous along a substantial portion of the length of the tubular member 620, or a majority of the length of the tubular member 620, or the diametrical gap can increase along one or more portions of the tubular member 620.

[0096] Figure 10B and Figure 10C Elevation views of the distal reinforcement member 634 are provided in different configurations illustrating its flexible, resilient, and deformable properties. Figure 10B The distal reinforcement member 634 is shown in a substantially circular configuration, which may be a resting, unconstrained configuration not bound by a stenotic vessel or guide catheter. Figure 10CAs shown in , this configuration can bend to a more elliptical oblong configuration in response to externally applied compression, constriction within the guide catheter, and / or anatomical changes (including vessel tortuosity and / or narrowing). The shape and configuration of the reinforcement member 634 can substantially conform to the interior surface of any surrounding structure, such that its configuration can be widely varied in different environments. 9A to 9D The embodiment of the coil member 534 shown in the figure can be similarly or identically configured in whole or in part so that the distal reinforcing member 634 and the coil member 534 can be flexible not only in its angle relative to the longitudinal axis of the pushing member, but also in its cross-sectional form. These deformable, deflectable and / or flexible characteristics can significantly enhance the versatility of the guide extension catheter 600 (for example, the guide extension catheter 500). For example, the distal reinforcing member 634 (and for example, the coil member 534) can be narrowed by ellipsoidal deformation so as to pass through a relatively narrow artery segment. The ellipsoidal deformation of the distal reinforcing member 634 also can help the tube member 620 pass through the guide catheter with a smaller cross-sectional area. Therefore, the radial expansion of the distal reinforcing member 634 can relate in whole or in part to the change of its cross-sectional form that occurs when the distal reinforcing member 634 leaves the distal end 604 of the guide catheter 602 or be consistent with it, so that even if the circumference of the distal reinforcing member 634 remains unchanged, the cross-sectional area of ​​the distal reinforcing member 634 also can increase. Within the guide catheter 602, the distal reinforcement member 634 can be deformed into various cross-sectional configurations, including, for example, Figure 10C Upon exiting the guide catheter 602, the distal reinforcement member 634 may exhibit a more annular circular cross-sectional configuration, e.g., Figure 10B The cross-sectional configuration of the distal reinforcement member can then continue to adjust in response to anatomical changes encountered during its advancement through the subject's vasculature, such that when traversing a tightly curved or narrow vessel, the distal reinforcement member can temporarily return to an approximately elliptical or irregular cross-sectional shape.

[0097] Figure 11A guide extension catheter is shown featuring a tubular member comprising a radially collapsible tubular membrane sandwiched on either side by two inflatable reinforcement members configured to enable selective, controlled expansion of the tubular member. Specifically, guide extension catheter 700 includes tubular member 720 having a distal end 724, a proximal end 726, and a radially collapsible tubular membrane 710 secured to a hollow pusher member 722. A first reinforcement member 706 comprising one or more inflatable helical coils is included at proximal end 726 of tubular member 720, and a second reinforcement member 734 comprising one or more inflatable helical coils is included at distal end 724 of tubular member 720. The lumen of each spiral structure can include a flexible, inflatable balloon arranged in a spiral configuration, and the lumen of each spiral structure can be continuous with the lumen of the hollow pushing member 722 so that the reinforcement member can be inflated when desired by injecting an inflation fluid into the proximal end of the hollow pushing member 722. Expansion of the reinforcement members 706, 734 causes the tubular membrane 710, and thus the tubular member 720 as a whole, to transition from a collapsed configuration to an expanded configuration, the latter as shown in FIG. Figure 11 , so as to be suitable for allowing one or more interventional devices to enter and pass therethrough.

[0098] The illustrated example includes two inflatable reinforcement members 706, 734, but additional embodiments may feature only one inflatable reinforcement member, disposed, for example, at the distal end or the proximal end of tubular member 720. Embodiments having only one inflatable reinforcement member may include additional, non-inflatable reinforcement members that include one or more of the features described above, for example, with respect to reinforcement members 306, 334, 506, 534, 606, and / or 634. For example, a guide extension catheter may include a proximal reinforcement member comprising one or more inflatable coils and a distal reinforcement member comprising an elastic ring or coil, for example, coil member 534 or distal reinforcement member 634.

[0099] In operation, one or both reinforcing members 706, 734 of the guide extension catheter 700 can be inflated to establish and / or maintain patency of the lumen 714 of the radially collapsible tubular membrane 710, thereby facilitating distal or proximal entry and passage of one or more interventional devices therein. During the course of a given procedure, one or more cycles of inflation and subsequent deflation of one or more reinforcing members can be performed to accommodate the replacement of various interventional devices.

[0100] The number of complete helical coils included in each reinforcement member 706, 734 can vary. Embodiments can feature one or more helical coils, for example, approximately two coils, three coils, four coils, five coils, or more. In embodiments featuring two reinforcement members, the number of inflatable coils included in each reinforcement member can be the same or different. For example, the proximal reinforcement member can feature two inflatable coils, while the distal reinforcement member can include only one inflatable coil.

[0101] The coils of the reinforcement members 706, 734 can be formed according to various methods, one of which can involve winding the expandable tube in a helical manner about a central axis into a series of windings that are subsequently stacked and bonded to one another, for example, as described in U.S. Patent No. 10,946,177, U.S. Patent No. 10,159,821, and U.S. Patent No. 9,968,763, the entire contents of which are incorporated herein by reference.

[0102] 12A to 12D Examples are shown for columnar strength, bending stiffness, radial strength, and tensile strength, respectively. Figure 12A A schematic top view of a tubular member 820 is shown, wherein arrows 825 indicate columnar forces. Thus, the term "columnar strength" refers to the structural resistance to one or more columnar forces 825. Figure 12B A schematic top view of a tube member 820 is shown, with arrows 835 indicating bending forces. Thus, the term "bending stiffness" (or bending strength) refers to the resistance of the structure to one or more bending forces 835. Figure 12C A schematic cross-sectional view of a tubular member 820 is shown, wherein arrows 845 indicate radial compressive forces. Thus, the term "radial strength" refers to the structural resistance to one or more radial compressive forces 845. Figure 12D A schematic cross-sectional view of a tubular member 820 is shown, wherein arrows 855 indicate tension or expansion forces. Thus, the term "tensile strength" refers to a structure's resistance to one or more tension forces 855.

[0103] Figure 13 A method for accessing a coronary artery, protecting the artery from wear or damage, and providing treatment to the artery is shown. Method 1300 may include step 1302: providing a guide catheter, which may include providing a guide catheter formed, for example, of polyurethane and shaped along its distal portion to facilitate advancement to the coronary ostium (or other area of ​​interest in the patient's body). A guide catheter of any size may be provided, for example, a 6F, 7F, or 8F guide catheter, where F is an abbreviation for the French catheter unit of measure (a unit for measuring the diameter of a catheter (1F = 8F)). 1 / 3mm)).

[0104] Method 1300 includes step 1304 of advancing a guide catheter, which includes advancing the guide catheter through a blood vessel to a position adjacent to the coronary ostium. In some embodiments, the guide catheter can be inserted into the femoral artery or radial artery and advanced through the aorta to a position adjacent to the coronary ostium. In some embodiments, the guide catheter can be guided by a guidewire, which optionally includes a steerable and / or deflectable guidewire tip. The guide catheter can include radiopaque markers to communicate the position of the guide catheter as it is advanced through the patient.

[0105] Method 1300 includes step 1306 of providing a guide extension catheter, wherein the guide extension catheter includes a push member and a tubular membrane wrapped around the push member. In some embodiments, the guide extension catheter includes a first reinforcement portion configured to maintain the patency of the lumen. The tubular membrane will have no effective columnar strength, no effective radial strength, and no effective bending stiffness. In other words, any radial force, columnar force, or bending force will cause the tubular membrane to deflect, collapse, and / or bend, and the tubular membrane will not provide effective resistance to radial force, columnar force, or bending force (e.g., see 7A to 7D The tubular film may exhibit a tensile strength sufficient to prevent tearing of the wall of the tubular film and sufficient to prevent micro- and / or macro-damage to the vessel wall during advancement of the interventional cardiology device.

[0106] Method 1300 includes step 1308 of advancing a guide extension catheter, wherein the guide extension catheter is advanced via the guide catheter to a position where at least a portion of the tubular membrane extends distally beyond a distal end of the guide catheter and into a coronary artery. In some embodiments, the guide extension catheter is advanced by providing an advancing force on a pushing member.

[0107] Method 1300 includes step 1310 of advancing an interventional cardiology device, which includes advancing the interventional cardiology device through a guide catheter into a lumen defined by a tubular membrane and causing the tubular membrane to expand from a collapsed, wrapped configuration to an expanded configuration. In some embodiments, advancing the interventional cardiology device into and through the lumen defined by the tubular membrane includes protecting an endothelial layer of a coronary artery from damage between a distal end of the guide catheter and a target tissue treatment area.

[0108] The devices, systems, and methods of the present invention provide or utilize delivery tools to reduce arterial damage caused by: (i) abrasion of the coronary endothelium during interventional device delivery, or (ii) coronary trauma / dissection caused by high delivery forces, active guide catheter occlusion, or relatively rigid guide extension catheters. In contrast to existing more rigid guide extension catheters, the present devices are configured to optimize (1) coronary vessel protection and (2) lubricity throughout the intracoronary delivery pathway.

[0109] The above detailed description contains references to the accompanying drawings, which form a part of the detailed description. The detailed description should be read with reference to the accompanying drawings. The accompanying drawings illustrate, by way of illustration, specific embodiments in which the apparatus, systems, and methods of the present invention may be practiced. These embodiments are also referred to herein as "examples."

[0110] The detailed description is intended to be illustrative and not restrictive. For example, the above examples (or one or more features or components thereof) may be used in combination with one another. For example, one or more features of guide extension catheters 300, 300', 500, 600, and / or 700 may be interchangeable. For example, guide extension catheters 300 and / or 310' may include a distal reinforcement member comprising coil member 534 and / or distal reinforcement member 634. Certain elements, although numbered differently in separate figures, may be identical or substantially identical in size, shape, material composition, and / or configuration. For example, radially collapsible tubular membrane 310 may be similar, identical, or readily interchangeable with radially collapsible tubular membranes 510 and / or 710. Similarly, push member 322 may be similar, identical, or readily interchangeable with push members 522 and / or 622. For example, other embodiments may be utilized by one of ordinary skill in the art after reviewing the detailed description and accompanying figures. Furthermore, various features or components have been or may be combined to streamline the present disclosure. This should not be interpreted as meaning that an unclaimed disclosed feature is essential to any claim. Rather, the subject matter of the invention may lie in less than all features of the disclosed embodiments. Thus, the following claims are hereby incorporated into the detailed description, with each example standing on its own as a separate embodiment.

[0111] In Example 1, a guide extension catheter can be positioned within a guide catheter and configured to receive an interventional device for insertion into a vascular system. The guide extension catheter can include a push member, a first reinforcement member in contact with the push member, and a radially collapsible tubular membrane in contact with the push member and the first reinforcement member. The tubular membrane can be positioned distal to the first reinforcement member and collapsed or wrapped around the push member before receiving the interventional device.

[0112] In Example 2, the guide extension catheter of Example 1 is optionally configured such that the tubular membrane has no effective cylindrical strength, no effective radial strength, no independent bending stiffness, but has a tensile strength sufficient to prevent tearing during insertion of the interventional device.

[0113] In Example 3, the guide extension catheter of either Example 1 or Example 2 is optionally configured such that the distal end of the pushing member extends distally of the distal end of the tubular membrane.

[0114] In Example 4, the guide extension catheter of Example 3 is optionally configured such that the distal end of the pushing member comprises an atraumatic guidewire-like distal end.

[0115] In Example 5, the guide extension catheter of Example 4 is optionally configured such that the atraumatic guidewire-like distal end comprises a tapered core surrounded by a coil.

[0116] In Example 6, the guide extension catheter of Example 5 is optionally configured such that the non-invasive guidewire-like distal end receives and maintains a user-induced curve.

[0117] In Example 7, the guide extension catheter of either Example 1 or 2 is optionally configured such that the distal end of the pushing member terminates at or near the distal end of the tubular membrane.

[0118] In Example 8, the guide extension catheter of any one or any combination of Examples 1-7 is optionally configured such that the push member tapers in one or more dimensions along a portion of its length.

[0119] In Example 9, the guide extension catheter of any one or any combination of Examples 1-8 is optionally configured such that the first reinforcement member comprises a deployable loop.

[0120] In Example 10, the guide extension catheter described in any one or any combination of Examples 1 to 8 is optionally configured such that the first reinforcing member defines a concave track leading into the tubular membrane and has a cylindrical strength and a radial strength greater than the cylindrical strength and radial strength of the tubular membrane.

[0121] In Example 11, the guide extension catheter of any one or any combination of Examples 1 to 10 is optionally configured such that the pushing member contacts the inner surface of the tubular membrane.

[0122] In Example 12, the guide extension catheter of any one or any combination of Examples 1 to 10 is optionally configured such that the pushing member contacts an outer surface of the tubular membrane.

[0123] In Example 13, the guide extension catheter of any one or any combination of Examples 1 to 10 is optionally configured such that the pushing member is fixed along a plane of the outer wall of the tubular membrane.

[0124] In Example 14, the guide extension catheter of any one or any combination of Examples 1 to 13 is optionally configured such that the tubular membrane is folded around the push member prior to receiving the interventional device.

[0125] In Example 15, the guide extension catheter of any one or any combination of Examples 1 to 14 is optionally configured such that the first stiffening member is secured to the pushing member and maintains patency of the lumen in the proximal end of the tubular membrane.

[0126] In Example 16, the guide extension catheter of any one or any combination of Examples 1 to 15 optionally further comprises a second reinforcing member disposed at the distal end of the tubular membrane, wherein the second reinforcing member is configured to maintain patency of the lumen at the distal end of the tubular membrane.

[0127] In Example 17, the guide extension catheter of Example 16 is optionally configured such that the second stiffening member selectively opens or closes the distal end of the tubular membrane.

[0128] In Example 18, the guide extension catheter of any one or any combination of Examples 1 to 17 is optionally configured such that the tubular membrane comprises a wall thickness and an outer diameter, wherein a ratio of the outer diameter to the wall thickness is in the range of 10:1 to 50:1, inclusive.

[0129] In Example 19, the guide extension catheter of any one or any combination of Examples 1 to 18 is optionally configured such that the tubular membrane is lubricous on one or both of the inner surface or the outer surface.

[0130] In Example 20, the guide extension catheter of any one or any combination of Examples 1 to 19 is optionally configured such that the tubular membrane is comprised of a lubricating layer, a non-cross-linked polymer layer, and a cross-linked polymer layer.

[0131] In Example 21, a guide extension catheter for use with a guide catheter may include a radially collapsible tubular membrane defining a lumen when biased to an open position, the lumen including a central axis, and a pushing member contacting the tubular membrane along the entire length of the tubular membrane and extending proximally of the tubular membrane for slidably positioning the tubular membrane within and partially beyond the distal end of the guide catheter. The tubular membrane has no significant radial strength and is configured to collapse toward the central axis when subjected to a radially inward biasing force. The tubular membrane may have a tensile strength sufficient to prevent tearing during insertion of an interventional cardiology device.

[0132] In Example 22, a method for accessing a coronary artery may include: providing a guide catheter; advancing the guide catheter through a blood vessel to a position adjacent to the coronary artery ostium; providing a guide extension catheter, the guide extension catheter comprising a push member and a radially collapsible tubular membrane, the radially collapsible tubular membrane wrapped around the push member prior to receiving an interventional device; advancing the guide extension catheter through the guide catheter to a position at which at least a portion of the tubular membrane extends distally beyond the distal end of the guide catheter and into the coronary artery; and advancing an interventional cardiology device through the guide catheter into a lumen defined by the tubular membrane, including driving the tubular membrane to expand from a collapsed configuration to an expanded configuration.

[0133] In Example 23, the method of Example 22 is optionally configured such that advancing the interventional cardiology device into and through the lumen defined by the tubular membrane includes protecting an endothelial layer of the coronary artery from damage between the distal end of the guide catheter and the target tissue treatment area.

[0134] Certain terms are used throughout this patent document to refer to features or components. Different people may refer to the same feature or component by different names. This patent document is not intended to distinguish between components or features that have different names but the same function.

[0135] The scope of the devices, systems, and methods of the present invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Furthermore, in the following claims, the terms "including" and "comprising" are open-ended; that is, devices, systems, or methods that include features or components in addition to those listed after such terms in a claim are considered to be within the scope of the claim. Furthermore, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels and are not intended to impose numerical requirements on their objects.

[0136] The abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Claims

1. A guide extension catheter positionable within a guide catheter and configured to receive an interventional device for insertion into a vasculature, the guide extension catheter comprising: Propelling member; a first reinforcing member in contact with the pushing member; as well as A radially collapsible tubular membrane is in contact with the pushing member and the first reinforcing member, the tubular membrane being positioned distal to the first reinforcing member and collapsed or wrapped around the pushing member prior to receiving the interventional device.

2. The guide extension catheter according to claim 1, wherein: The tubular membrane has no significant cylindrical strength, no significant radial strength, no independent bending stiffness, but has sufficient tensile strength to prevent tearing during insertion of the interventional device.

3. The guide extension catheter according to claim 1, wherein: The distal end of the pushing member extends distally of the distal end of the tubular film.

4. The guide extension catheter according to claim 3, wherein: The distal end of the pushing member includes an atraumatic guidewire-like distal end.

5. The guide extension catheter according to claim 4, wherein: The atraumatic guidewire distal tip includes a tapered core surrounded by a coil.

6. The guide extension catheter according to claim 5, wherein: The non-invasive guidewire-like distal end is configured to receive and maintain a user-induced curve.

7. The guide extension catheter according to claim 1, wherein: The distal end of the pushing member terminates at or near the distal end of the tubular membrane.

8. The guide extension catheter of claim 1, wherein: The pushing member tapers in one or more dimensions along a portion of its length.

9. The guide extension catheter of claim 1, wherein: The first reinforcement member comprises a deployable loop.

10. The guide extension catheter of claim 1, wherein: The first reinforcing member defines a concave track leading into the tubular membrane and has a cylindrical strength and a radial strength that are greater than those of the tubular membrane.

11. The guide extension catheter of claim 1 , wherein: The pushing member is in contact with the inner surface of the tubular film.

12. The guide extension catheter of claim 1, wherein: The pushing member is in contact with the outer surface of the tubular film.

13. The guide extension catheter of claim 1, wherein: The pushing member is fixed along the plane of the outer wall of the tubular membrane.

14. The guide extension catheter of claim 1, wherein: The tubular film is configured to be folded around the pushing member prior to receiving the interventional device.

15. The guide extension catheter of claim 1, wherein: The first stiffening member is secured to the pushing member and is configured to maintain patency of the lumen in the proximal end of the tubular membrane. 16 . The guide extension catheter of claim 15 , further comprising a second reinforcing member disposed at a distal end of the tubular membrane, the second reinforcing member configured to maintain patency of the lumen at the distal end of the tubular membrane.

17. The guide extension catheter of claim 16, wherein: The second reinforcing member is configured to selectively open or close the distal end of the tubular membrane.

18. The guide extension catheter of claim 1, wherein: The tubular membrane comprises a wall thickness and an outer diameter, wherein a ratio of the outer diameter to the wall thickness is in the range of 10:1 to 50:1, inclusive.

19. The guide extension catheter of claim 1, wherein: The tubular membrane is lubricious on one or both of the inner or outer surfaces.

20. The guide extension catheter of claim 1, wherein The tubular film is composed of a lubricating layer, a non-crosslinked polymer layer and a crosslinked polymer layer.

21. A guide extension catheter for use with a guide catheter, the guide extension catheter comprising: a radially collapsible tubular membrane defining a lumen when biased to an open position, the lumen including a central axis; as well as a pushing member in contact with the tubular membrane along the entire length of the tubular membrane and extending proximally of the tubular membrane for slidably positioning the tubular membrane within and partially beyond the distal end of the guide catheter, wherein the tubular membrane has no significant radial strength and is configured to collapse toward the central axis when subjected to a radially inward biasing force, the tubular membrane comprising a tensile strength sufficient to prevent tearing during insertion of an interventional cardiology device.

22. A method for accessing a coronary artery, the method comprising: Provide a guide catheter; advancing the guide catheter through a blood vessel to a position adjacent to the coronary artery ostium; A guide extension catheter is provided, the guide extension catheter comprising: Push member, and a radially collapsible tubular membrane that is wrapped around the pushing member prior to receiving the interventional device; advancing the guide extension catheter through the guide catheter to a position where at least a portion of the tubular membrane extends distally beyond the distal end of the guide catheter and into the coronary artery; and Advancing an interventional cardiology device through the guide catheter into the lumen defined by the tubular membrane includes actuating expansion of the tubular membrane from a collapsed configuration to an expanded configuration.

23. The method according to claim 22, wherein Advancing the interventional cardiology device into and through the lumen defined by the tubular membrane includes protecting an endothelial layer of the coronary artery from damage between a distal end of the guide catheter and a target tissue treatment area.

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