Support catheter and associated loading components

Abstract

Fissure support catheters, loading tools, and methods of use are disclosed. The support catheters can include an elongated tubular member and a push member. The tubular member can include a longitudinal slit configured to accommodate exchange of various interventional devices into and out of a lumen defined by the tubular member. The loading tools can include a body member, a rod member, or both, and can facilitate loading of the support catheter onto one or more interventional devices during a medical procedure. The support catheters can provide intravascular support for various interventional devices, and can be advantageously inserted and removed without first removing an interventional device having a distal end located at or near a target site within a patient's vasculature.

Description

[0001] Priority requirements

[0002] This non-provisional patent document claims priority to U.S. Provisional Patent Application Serial No. 63 / 149,510, filed February 15, 2021, entitled “EXPANDABLE SPLIT SUPPORT CATHETER AND LOADING TOOL DESIGNS, METHODS FOR MANUFACTURE AND METHODS FOR USE”, filed under 35 USC § 119(e), which is incorporated herein by reference in its entirety. Technical Field

[0003] This patent document relates to medical devices. More specifically, but not in a limiting way, this patent document relates to a support catheter having features configured to support other interventional devices within a patient's vascular system. Accessory devices configured to assemble the support catheter with various interventional devices are also disclosed. Background Technology

[0004] When an interventional device, such as a guidewire, balloon catheter, stent, or stent catheter, passes through and advances beyond the distal end of the guiding catheter, the guiding catheter can be withdrawn from the vascular orifice or branch. This withdrawal of the guiding catheter results in the surgeon losing the ability to advance the interventional device further distally. Due to the lack of backup support, the interventional device itself may also be unable to enter or pass through the treatment site, such as the lesion. Before initiating the procedure, the surgeon must select a device configured to prevent guide catheter withdrawal and provide additional anchoring support for the interventional device to avoid the need to remove one or more devices from the patient's vascular system during the procedure. Invention Overview

[0006] The inventors recognize that the need to provide additional backup support for interventional devices (e.g., guide catheters) during interventional procedures can be unpredictable. They also recognize that once advanced along the vessel during the interventional procedure, the support catheter increases the success rate by "anchoring" the interventional device in the vessel, making it less likely to be dislodged or removed from the target site as another interventional device (e.g., balloon or stent delivery system) is advanced. Furthermore, the inventors recognize that the support catheter reduces friction between the interventional device and the surrounding vessel wall, making it less likely for the device to become lodged in calcified or diseased upstream vessel wall tissue. The inventors recognize that support catheters are increasingly used in chronic total occlusion (CTO) and percutaneous coronary intervention (PCI) procedures to increase guide support and also to provide a target for the re-entry of the retrograde wire. The inventors recognize that another useful function of the support catheter is to facilitate selective delivery of contrast agents (e.g., to desired branch vessels), thereby improving angiographic imaging while reducing contrast agent volume.

[0007] The inventors recognize that existing commercially available support catheters can consist of a proximal handle, a flexible distal tubular structure, and a pusher connecting the handle to the tube. The distal tubular structure may include one (or more) radiopaque elements so that it can be visualized, such as circular platinum-iridium (Pt-Ir) marking strips. The distal tube is typically a full-circular tube, and its wall may consist of an inner lubricating layer (such as a PTFE lining), a support material (such as stainless steel braid), and a polymer outer layer (such as nylon, Pebax®, etc.).

[0008] The inventors further recognized that some existing support catheters have an outer diameter of approximately 5F, configured for advancement via a 6F guide catheter, where F is an abbreviation for the French catheter scale (a unit of measurement for catheter diameter, 1F = 1 / 3 mm). 4F, 6F, and 7F support catheters are also available on the market. Typically, a 4F catheter has an inner diameter greater than or equal to 0.050 inches. Typically, a 5F catheter has an inner diameter greater than or equal to 0.059 inches, a 6F catheter has an inner diameter greater than or equal to 0.070 inches, and a 7F catheter has an inner diameter greater than or equal to 0.078 inches. It should be understood that because the wall thickness of the tubular component of the support catheter can vary, and because a certain amount of space is required between the tubular component of the support catheter and the inner wall of the guide catheter, the inner diameter of the tubular component of the support catheter can vary when no device such as an interventional cardiology device is inserted into the catheter, and can be smaller than the inner diameter of a correspondingly sized guide catheter. For example, while a standard 5F guiding catheter may have an inner diameter of 0.059 inches or larger, the 5F support catheter of the present invention, in its resting state (with nothing inserted or passing through it), may have an inner diameter of approximately any of the following: 0.052 inches or smaller, 0.053 inches, 0.054 inches, 0.055 inches, 0.056 inches, 0.057 inches, 0.058 inches, or 0.059 inches or more. If the tubular component of the support catheter is in an extended state (e.g., an interventional cardiology device has been inserted therein), the diameter of the tubular component of the support catheter may be extended beyond the diameter of the tubular component in its resting state. Certain standard coronary balloon and stent delivery systems can be advanced and withdrawn using a 5F support catheter. Relatively large catheter systems can be used during rotational atherectomy, bifurcation PCI procedures, and some CTO procedures (e.g., via balloon anchoring). The diameter of the support catheter affects how easily it can be advanced along the coronary artery, especially considering that challenging interventional procedures that require guidance through vessels with upstream tortuosity, disease, and calcification often require a support catheter.

[0009] The inventors also recognized that, to use existing commercially available support catheter designs, users typically must first advance the distal tubular structure of the support catheter along the guidewire and into the guiding catheter and / or blood vessel. The user must then advance the interventional device (e.g., balloon, stent, etc.) along the guidewire through the guiding catheter and through the support catheter to reach the target lesion. Therefore, existing commercially available designs do not allow for the insertion of the support catheter after the interventional device, meaning that users must pre-select whether to use the support catheter or completely withdraw the interventional device if the support catheter is needed so that the support catheter can be loaded into the guiding catheter first.

[0010] Similarly, the inventors recognized that once the lesion is treated, the interventional device must be completely removed so that the support catheter can be removed subsequently, or both must be removed together. The user cannot remove the existing support catheter after use while leaving the interventional device in the vascular system.

[0011] One reason why current support catheters cannot be directly loaded onto or removed from interventional devices is that these devices typically have large proximal Luer joints or hubs that prevent loading the tubular support catheter onto its proximal end. Therefore, the interventional device must be placed after the support catheter is inserted. A related disadvantage of the entire procedure recognized by the inventors includes requiring the user to pre-select (guess) when the support catheter will be needed and load it first to address difficult situations. This approach generally results in more expensive and longer procedures. Without a pre-selected support catheter, the user must withdraw the carefully placed interventional device, load the support catheter, and then reload the interventional device. This also leads to longer and more expensive procedures. Furthermore, the support catheter cannot be withdrawn independently after treatment with the interventional device, which complicates the interventional procedure.

[0012] Furthermore, the inventors recognize that current tubular support catheters typically have fixed inner and outer diameters and are neither tapered nor expandable. This means that there will inherently be dimensional differences between the inner diameter of the guiding catheter and the outer diameter of the support catheter, as well as between the inner diameter of the support catheter and the outer diameter of the interventional device. Excessive dimensional differences between these surfaces can result in lower support force, as the thrust applied to the proximal end of the device will not translate into 100% forward propulsion. Conversely, if the radial clearance between devices is too large, conventional flexible catheters may bend or even deform. A primary reason for using support catheters is to constrain the interventional device to ensure that the thrust applied proximally effectively drives the device forward. This also means that existing support catheters are inserted into the vessel at their maximum configuration to allow the interventional device to pass through, and because they are not expandable, it makes it more difficult to track the device along tight vessels.

[0013] The inventors also recognized a contradiction between using the smallest possible diameter support catheter (so that the interventional device is securely restrained and the support catheter can therefore be more easily tracked along tight blood vessels) and using the largest possible guide catheter (to improve support for the interventional device). It might be possible to fit the support catheter even tightly to the guidewire to improve wire support and maneuvering, or to fit it as tightly as possible to the interventional device. Existing support catheters with a fixed diameter cannot effectively accommodate the guide catheter, interventional device, and guidewires of different diameters, and the support catheter does not have the ability to expand in diameter if a larger device is inserted through it.

[0014] The support catheter disclosed herein can be advantageously deployed "immediately" after the start of the interventional procedure, i.e., without user pre-selection, to provide effective backup support for at least one interventional device already inserted into the blood vessel. A longitudinal slit defined in the distal tubular member of the disclosed support catheter allows the user to insert the support catheter posterior to and above the interventional device by widening the slit in the distal tubular member and inserting a portion of the interventional device into the distal tubular member. Similarly, the support catheter can be decoupled from the interventional device by pushing the interventional device out through the longitudinal slit in the distal tubular member of the support catheter. Loading the support catheter onto the interventional device after determining that backup support is needed provides surgical flexibility not available with existing devices, similar to unloading the support catheter during the procedure. To facilitate the coupling (or installation) process, accessory devices including loading tools and optional binding tools particularly advantageous for certain interventional procedures are also disclosed herein.

[0015] Because the disclosed support catheters can be expandable, they can also be used in procedures that typically require catheters with larger diameters. The reduced device profile increases the ease of catheter advancement along the coronary artery (or other vessels). This reduces the need for more aggressive approaches to distal advancement of the support catheter (e.g., balloon anchoring in distal vessels), which are associated with an increased risk of upstream vessel dissection. The disclosed support catheters may have a reduced diameter only at the distal tip of a slender tubular member with a longitudinal slit or along its entire length.

[0016] The vascular anchoring provided by the disclosed support catheter can be improved relative to existing devices, primarily because the support catheter can be inserted deeply into the blood vessel. The disclosed support catheter can also be used to maintain the protection and support of the stent delivery system, as the stent on its delivery balloon remains encased around almost the entire circumference of the system.

[0017] Another advantage of the disclosed scalable slit support catheter implementation is that the catheter can be "clamped" in situ onto the guidewire and balloon / stent delivery catheter axis, for example near the Tuohy-Borst hemostatic valve (which is mounted on the proximal end of the guiding catheter), and then advanced through the guiding catheter and along the coronary artery, all without first removing the balloon / stent delivery catheter from the patient.

[0018] The inventors further recognize that it also offers the advantage of faster and easier removal of the support catheter from the patient. The disclosed support catheter can be withdrawn and removed from the guidewire and interventional device axis in a “stripping” manner, which may involve withdrawing the tubular component of the support catheter from the guiding catheter and stripping the tubular component from the inserted wire / treatment device.

[0019] In some embodiments, the support catheter of this disclosure may include a longer distal segment (30-40 cm), a relatively short axis, and optionally added distal bends to provide directional control within the cardiac chambers and when passing through the tricuspid valve. These and related embodiments can allow delivery of the pacing lead to optimal locations in the right atrium and right ventricle, and for left ventricular pacing in coronary veins accessed via the coronary sinus. This type of catheter optionally has distal bends, allowing for directional control of its distal end. The support catheter can be inserted through a short, straight vascular sheath or through a longer sheath with distal bends designed, for example, to engage the coronary sinus. Once the pacing lead is secured in place, the stripping feature allows for easy removal with minimal risk of lead displacement.

[0020] Various other improvements to the design, implementation, construction, and / or use of support catheters are described in U.S. Patent No. 10,173,029 entitled “Deflection Control Catheters, Support Catheters and Methods of Use,” the entire teachings of which are incorporated herein by reference.

[0021] These and other examples and objectives of the support catheter, loading component, and related methods of the present invention will be set forth in the detailed description below. This overview is intended to provide non-limiting examples of the subject matter; it is not intended to provide an exclusive or exhaustive explanation. The following detailed description is included to provide more information regarding the support catheter, loading component, and related methods of the present invention. Attached Figure Description

[0022] In the accompanying drawings, similar reference numerals may be used in several views to describe similar features and components. The drawings generally illustrate, by way of example and not limitation, the various embodiments discussed in this patent document.

[0023] Figure 1A A partial cross-sectional side view of a support conduit constructed according to at least one embodiment is shown.

[0024] Figure 1B It shows Figure 1A The diagram shows a plan view of the support conduit.

[0025] Figure 1C It shows that it includes Figure 1A A partial side view of the pushing member in the support conduit shown.

[0026] Figure 1D It shows along Figure 1A An enlarged sectional view of the support conduit taken along line AA.

[0027] Figure 1E It shows in Figure 1BA magnified side view of the distal portion of the tubular component supporting the conduit, taken at detail point A.

[0028] Figure 1F It shows along Figure 1A An enlarged sectional view of the support conduit taken along line AA, showing the layers and dimensions of the tubular member wall and inner lumen.

[0029] Figure 1G It shows that it includes Figure 1A A side view of the marking strip in the support conduit shown.

[0030] Figure 1H It shows Figure 1G The side view of the cross section of the marked band shown.

[0031] Figure 1I It shows that it contains Figure 1H A cross-sectional side view of the distal tubular member of the marked band shown.

[0032] Figure 2A A partial plan view of a support conduit including a tapered tubular member, constructed according to at least one embodiment, is shown.

[0033] Figure 2B It shows in Figure 2A An enlarged sectional view of the support conduit taken at line AA.

[0034] Figure 2C It shows in Figure 2A An enlarged cross-sectional view of the support conduit taken at the BB line.

[0035] Figure 2D It shows in Figure 2A An enlarged cross-sectional view of one embodiment of the support conduit, taken at the BB line.

[0036] Figure 2E It shows in Figure 2A An enlarged cross-sectional view of another embodiment of the support conduit, taken at the BB line.

[0037] Figure 3A A perspective view of a support conduit comprising a tubular member in a narrowing configuration, as constructed according to at least one embodiment, is shown.

[0038] Figure 3B Showing the expanded configuration Figure 3A A perspective view of the supporting conduit.

[0039] Figure 4A A partial plan view of a support conduit including a shortened longitudinal slit, constructed according to at least one embodiment, is shown.

[0040] Figure 4B It shows in Figure 4A An enlarged sectional view of the support conduit taken at line AA.

[0041] Figure 4C It shows in Figure 4A An enlarged cross-sectional view of the support conduit taken at the BB line.

[0042] Figure 5A An enlarged cross-sectional view of a tubular member supporting a conduit, constructed according to at least one embodiment, is shown.

[0043] Figure 5B An enlarged cross-sectional view of another tubular member supporting the conduit, constructed according to at least one embodiment, is shown.

[0044] Figure 5C It shows Figure 5A An enlarged cross-sectional view of the tubular member after the intervention device has been inserted.

[0045] Figure 5D It shows Figure 5B An enlarged cross-sectional view of the tubular member after the intervention device has been inserted.

[0046] Figure 6 A perspective view of a support conduit comprising a variable stiffness tubular member, constructed according to at least one embodiment, is shown.

[0047] Figure 7 A perspective view of another support conduit constructed according to at least one embodiment is shown.

[0048] Figure 8A A perspective view of a support conduit including a notched longitudinal slit, constructed according to at least one embodiment, is shown.

[0049] Figure 8B It shows in Figure 8A An enlarged sectional view of the support conduit taken at line AA.

[0050] Figure 8C This illustrates the situation when the support catheter is decoupled from the interventional device. Figure 8A A perspective view of the supporting conduit.

[0051] Figure 9 A perspective view of a support conduit having a distal tubular structure defining a proximal lateral opening, as constructed according to at least one embodiment, is shown.

[0052] Figure 10 A partial plan view of another support conduit constructed according to at least one embodiment is shown.

[0053] Figure 11A perspective view of a support conduit, including a curved distal end, constructed according to at least one embodiment, is shown.

[0054] Figure 12A An enlarged cross-sectional view of the distal end of a support catheter, constructed according to at least one embodiment, is shown.

[0055] Figure 12B An enlarged cross-sectional view of the distal end of another support catheter, constructed according to at least one embodiment, is shown.

[0056] Figure 12C An enlarged cross-sectional view of the distal end of another support catheter, constructed according to at least one embodiment, is shown.

[0057] Figure 13A A cross-sectional side view of a support conduit, including a braided structure, constructed according to at least one embodiment, is shown.

[0058] Figure 13B It shows in Figure 13A The enlarged cross-sectional view of the support conduit taken at point A.

[0059] Figure 13C It shows Figure 13A The side view of the support conduit shown.

[0060] Figure 13D It shows in Figure 13C The enlarged cross-sectional view of the support conduit taken at detail point B.

[0061] Figure 14A The initial steps of a method for forming a support catheter according to at least one embodiment are shown.

[0062] Figure 14B The subsequent steps of the method are shown.

[0063] Figure 14C The subsequent steps of the method are shown.

[0064] Figure 14D The subsequent steps of the method are shown.

[0065] Figure 15A A cross-sectional side view of a support conduit including a metal support structure, constructed according to at least one embodiment, is shown.

[0066] Figure 15B It shows Figure 15A The perspective view of the support conduit shown.

[0067] Figure 16A A perspective view of a tubular member comprising a metal support frame and a support conduit, constructed according to at least one embodiment, is shown.

[0068] Figure 16B It shows Figure 16A The image shows a cross-sectional view of the tubular component.

[0069] Figure 16C It shows Figure 16A The plan view of the metal support frame for the tubular component shown.

[0070] Figure 16D It shows that it can be included Figure 16A A plan view of an alternative embodiment of the metal support frame in the tubular member shown.

[0071] Figure 16E It shows that it can be included Figure 16A A plan view of an alternative embodiment of the metal support frame in the tubular member shown.

[0072] Figure 16F It shows that it can be included Figure 16A A plan view of an alternative embodiment of the metal support frame in the tubular member shown.

[0073] Figure 16G It shows that it can be included Figure 16A A plan view of an alternative embodiment of the metal support frame in the tubular member shown.

[0074] Figure 16H A plan view of an alternative embodiment of a metal support frame that can be included in a tubular member supporting a conduit is shown.

[0075] Figure 16I It shows including Figure 16H An enlarged perspective view of a portion of the tubular component of the metal support frame shown.

[0076] Figure 16J It shows Figure 16H A partial plan view of a portion of the metal support frame shown.

[0077] Figure 16K A plan view of an alternative embodiment of a metal support frame that may be included in a tubular member supporting a conduit is shown.

[0078] Figure 17 A perspective view of a tubular member comprising an embedded metal strip and a support conduit, constructed according to at least one embodiment, is shown.

[0079] Figure 18A A perspective view of a support conduit constructed according to at least one embodiment is shown.

[0080] Figure 18B The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0081] Figure 18C The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0082] Figure 18D The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0083] Figure 18E The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0084] Figure 18F The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0085] Figure 18G The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0086] Figure 18H The image shown is taken along line AA and can be included. Figure 18A An enlarged cross-sectional view of the pushing component in the support conduit.

[0087] Figure 18I A perspective view of a support conduit, including a pushing member, as constructed according to at least one embodiment, is shown.

[0088] Figure 19A A perspective view of a support conduit including a partially embedded actuating member, constructed according to at least one embodiment, is shown.

[0089] Figure 19B A perspective view of another support conduit, including a partially embedded actuating member, as constructed according to at least one embodiment, is shown.

[0090] Figure 20A A perspective view of a support conduit including a bifurcated pusher member, constructed according to at least one embodiment, is shown.

[0091] Figure 20B The image shown is taken along line AA. Figure 20A The enlarged cross-sectional view of the support conduit shown.

[0092] Figure 21A perspective view of a support catheter and a compatible interventional device, constructed according to at least one embodiment, is shown.

[0093] Figure 22A A schematic snapshot is shown of a method using a support catheter and associated interventional device, as constructed according to at least one embodiment.

[0094] Figure 22B It shows in Figure 22A A schematic snapshot of the proximal portion of the catheter and associated interventional device during the method shown.

[0095] Figure 23 A perspective view of a support catheter, decoupled from the interventional device, constructed according to at least one embodiment, is shown.

[0096] Figure 24A A perspective view is shown of a technique for loading a support catheter with an interventional device, as constructed according to at least one embodiment.

[0097] Figure 24B A perspective view is shown of another technique for loading a support catheter with an interventional device, as constructed according to at least one embodiment.

[0098] Figure 25A A schematic diagram of a support catheter coupled to an interventional device, constructed according to at least one embodiment, is shown.

[0099] Figure 25B A schematic diagram of a support catheter coupled to an interventional device, constructed according to at least one embodiment, is shown.

[0100] Figure 26 An enlarged view is shown of the distal portion of a support catheter, which is close to a part of an interventional device, as constructed according to at least one embodiment.

[0101] Figure 27 A loading tool, constructed according to at least one embodiment, is shown, configured to facilitate coupling of a support catheter with an interventional device.

[0102] Figure 28A A perspective view is shown of a loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0103] Figure 28B It shows Figure 28A The diagram shows the loading tool.

[0104] Figure 28C It shows Figure 28A The side view of the loading tool shown.

[0105] Figure 28DIt shows Figure 28A The other side view of the loading tool shown.

[0106] Figure 28E It shows in Figure 28D The detail was captured at point A. Figure 28A An enlarged side view of the loading tool shown.

[0107] Figure 28F It shows Figure 28A The image shows a longitudinal side view of the loading tool.

[0108] Figure 29A A perspective view is shown of a loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0109] Figure 29B It shows Figure 29A The diagram shows the loading tool.

[0110] Figure 29C It shows Figure 29A The side view of the loading tool shown.

[0111] Figure 29D It shows in Figure 29C The detail was captured at point A. Figure 29A An enlarged side view of the loading tool shown.

[0112] Figure 30A A perspective view is shown of a loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0113] Figure 30B It shows Figure 30A The diagram shows the loading tool.

[0114] Figure 30C It shows Figure 30A The side view of the loading tool shown.

[0115] Figure 30D It shows Figure 30A The other side view of the loading tool shown.

[0116] Figure 30E It shows in Figure 30D The detail was captured at point A. Figure 30A An enlarged side view of the loading tool shown.

[0117] Figure 30F It shows Figure 30A The image shows a longitudinal side view of the loading tool.

[0118] Figure 31AA perspective view is shown of a loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0119] Figure 31B It shows Figure 31A The diagram shows the loading tool.

[0120] Figure 31C It shows Figure 31A The image shows a longitudinal side view of the loading tool.

[0121] Figure 31D It shows Figure 31A The other side view of the loading tool shown.

[0122] Figure 32A A plan view is shown of a loading tool configured to facilitate coupling of a support catheter and an interventional device, as constructed according to at least one embodiment.

[0123] Figure 32B The image shown is taken along line AA. Figure 32A The cross-sectional view of the loading tool shown.

[0124] Figure 32C The image shown is a cutoff at detail B. Figure 32B An enlarged cross-sectional view of the loading tool shown.

[0125] Figure 33A A plan view is shown of a loading tool configured to facilitate coupling of a support catheter and an interventional device, as constructed according to at least one embodiment.

[0126] Figure 33B The image shown is taken along line AA. Figure 33A The cross-sectional view of the loading tool shown.

[0127] Figure 33C The image shown is a cutoff at detail B. Figure 33B An enlarged cross-sectional view of the loading tool shown.

[0128] Figure 34 A perspective view is shown of another loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0129] Figure 35 A perspective view is shown of another loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0130] Figure 36 A perspective view is shown of a loading tool configured to facilitate coupling of a support catheter with an interventional device, as constructed according to at least one embodiment.

[0131] Figure 37 A perspective view is shown of another loading tool, constructed according to at least one embodiment, configured to facilitate coupling of a support catheter with an interventional device.

[0132] Figure 38A A loading tool, constructed according to at least one embodiment, is shown, configured to facilitate coupling of a support catheter with an interventional device.

[0133] Figure 38B It shows Figure 38A A cross-sectional view of a portion of the loading tool shown.

[0134] Figure 38C It shows Figure 38A A cross-sectional view of a portion of an alternative form of the loading tool shown.

[0135] Figure 38D It shows Figure 38A A cross-sectional view of a portion of an alternative form of the loading tool shown.

[0136] Figure 38E It shows Figure 38A A cross-sectional view of a portion of an alternative form of the loading tool shown.

[0137] Figure 38F It shows Figure 38A A cross-sectional view of a portion of an alternative form of the loading tool shown.

[0138] Figure 38G It shows Figure 38A A cross-sectional view of a portion of an alternative form of the loading tool shown.

[0139] Figure 39 A loading tool comprising a groove and a rod, constructed according to at least one embodiment and configured to facilitate coupling of a catheter to an interventional device, is shown.

[0140] Figure 40 A support conduit, constructed according to at least one embodiment, is shown for proximity to a loading tool including a rod.

[0141] Figure 41 A support conduit for a loading tool, including a rod and a handle, is shown, constructed according to at least one embodiment.

[0142] Figure 42 A loading tool, constructed according to at least one embodiment, is shown, including a ring-shaped feature for user gripping.

[0143] Figure 43 A binding tool coupled to a guidewire and interventional device, as constructed according to at least one embodiment, is shown.

[0144] Figure 44 Another bundling tool as constructed according to at least one embodiment is shown.

[0145] Figure 45 Another bundling tool as constructed according to at least one embodiment is shown.

[0146] Figure 46 A loading tool, constructed according to at least one embodiment, is shown, comprising an integrated strapping feature coupled to a guidewire and interventional device.

[0147] Figure 47 A loading tool comprising a rod and a bundle tube, constructed according to at least one embodiment, is shown.

[0148] Figure 48 A loading tool comprising a single tube, as constructed according to at least one embodiment, is shown.

[0149] Figure 49 A loading tool including a countersunk channel, as constructed according to at least one embodiment, is shown.

[0150] Figure 50A A schematic diagram is shown of a method for inserting a pacemaker lead into a vascular target site according to the disclosed embodiment.

[0151] Figure 50B It shows Figure 50A A schematic diagram of the subsequent steps of the method shown.

[0152] Figure 50C It shows Figure 50B A schematic diagram of the subsequent steps of the method shown.

[0153] Figure 50D It shows Figure 50C A schematic diagram of the subsequent steps of the method shown.

[0154] Figure 50E It shows Figure 50D A schematic diagram of the subsequent steps of the method shown.

[0155] Figure 50F It shows Figure 50E A schematic diagram of the subsequent steps of the method shown.

[0156] Figure 50G It shows Figure 50F A schematic diagram of the subsequent steps of the method shown.

[0157] Figure 51A A schematic diagram of a method for treating bifurcation lesions according to the disclosed implementation scheme is shown.

[0158] Figure 51BIt shows Figure 51A A schematic diagram of the subsequent steps of the method shown.

[0159] Figure 51C It shows Figure 51B A schematic diagram of the subsequent steps of the method shown.

[0160] Figure 51D It shows Figure 51C A schematic diagram of the subsequent steps of the method shown.

[0161] Figure 51E It shows Figure 51D A schematic diagram of the subsequent steps of the method shown.

[0162] Figure 51F A schematic diagram of a support catheter inserted via a guide catheter and an introducer sheath is shown.

[0163] Figure 51G It shows Figure 51F A schematic diagram of the subsequent steps of the method shown.

[0164] Figure 51H It shows Figure 51G A schematic diagram of the subsequent steps of the method shown.

[0165] Figure 51I It shows Figure 51H A schematic diagram of the subsequent steps of the method shown.

[0166] Figure 52A A schematic diagram of a method for inflating a treatment balloon according to the disclosed embodiment is shown.

[0167] Figure 52B It shows Figure 52A A schematic diagram of the subsequent steps of the method shown.

[0168] Figure 52C It shows Figure 52B A schematic diagram of the subsequent steps of the method shown.

[0169] Figure 52D It shows Figure 52C A schematic diagram of the subsequent steps of the method shown.

[0170] Figure 52E It shows Figure 52D A schematic diagram of the subsequent steps of the method shown.

[0171] Figure 53A A schematic diagram of a posteriorly loaded support catheter on an interventional device is shown.

[0172] Figure 53B A schematic diagram of the support catheter and interventional device inside the guiding catheter is shown.

[0173] The accompanying drawings are not necessarily drawn to scale. Some features and parts may be shown at an enlarged scale or as schematic diagrams, and some details may not be suitable for the purpose of clarity and conciseness. Invention Details

[0175] Various embodiments and aspects of this disclosure will be described with reference to the details discussed below, and the accompanying drawings will illustrate the various embodiments. The following description and drawings are generally illustrative of this disclosure and should not be construed as limiting. Numerous specific details are described to provide a thorough understanding of the various embodiments of this disclosure. However, in some cases, well-known or conventional details have not been described in order to provide a concise discussion of embodiments of this disclosure.

[0176] This patent document specifically discloses a support catheter to be placed within a guiding catheter, which provides support and guidance in a blood vessel during percutaneous advancement of interventional devices (e.g., guidewires, balloon catheters, stents, or stent catheters). The support catheter can be inserted into the blood vessel after determining that one or more inserted interventional devices require or may benefit from additional support. Assistive devices for loading the support catheter onto the in-place interventional device are also disclosed. The support catheter of this invention has applications in coronary, peripheral, and other vascular systems.

[0177] The support catheters disclosed herein may include a guide extension catheter configured to pass through the main lumen of a guide catheter such that its distal end portion can extend beyond the distal end of the guide catheter, for example as described in U.S. Patent Nos. 8,048,032 (and its divisions) and 10,751,514, all of which are incorporated herein by reference in their entirety.

[0178] As used herein, an "interventional device" is any device inserted into a patient's vascular system to treat a medical condition. Interventional devices can provide therapeutic and / or surgical support. For example, an interventional device can be used to treat medical problems such as vascular occlusion or stenosis, and / or an interventional device can be used to guide another interventional device to the treatment site, where the interventional device can anchor or position the other device. For these purposes, interventional devices are typically elongated devices with a diameter small enough to fit within a patient's blood vessel. Interventional devices deployed to treat, for example, vascular lesions may include a treatment catheter with therapeutic structures such as an inflatable balloon, a stent, and / or a threaded portion configured to drill through the distal portion of the lesion. In some embodiments, an interventional device may include an interventional cardiology device. Additional non-limiting, non-exhaustive examples of interventional devices contemplated herein include: stents, stent delivery devices, balloon catheters, balloon delivery devices, and / or pacemaker leads. For consistency and ease of illustration only, "interventional device" and "support catheter" refer herein to separate devices.

[0179] As used herein, "user" can be defined as a person who guides the disclosed support catheters and interventional devices into and out of a patient's vascular system during a medical procedure. Non-limiting examples of users contemplated herein include medical professionals such as treating clinicians, nurses, physicians, interventional cardiologists, and / or physician assistants.

[0180] The term “blood vessel” in this document may be defined as any blood vessel within a patient’s vascular system, and non-limiting examples may include various arteries and veins, including their branches and orifices. Specific examples may include coronary arteries, but it should be understood that support catheters may also be used to treat non-coronary artery lesions throughout the patient’s body, the peripheral vascular system, the neurovascular system, or other hollow structures (e.g., bile ducts, ureters, etc.).

[0181] The support catheter described herein (also referred to herein as an "expandable slit support catheter," "slit support catheter," or "guided extension catheter") facilitates the intravascular guidance and fixation of elongated interventional devices during various medical procedures, such as percutaneous procedures targeting hard-to-reach branch vessels. A medical device delivery system may comprise at least one interventional device and a support catheter configured to couple and span one (or more) interventional devices in an on-wire or rapid-exchange configuration. Once coupled to the interventional device, the support catheter can help resist axial and shear forces that often displace the interventional device from its in-situ location, which may contain an orifice of a branch artery.

[0182] One embodiment of the scalable support conduit 100 according to the principles of this disclosure is... Figure 1A-1F As shown in the diagram. Among other features, the support catheter also includes an expandable longitudinal slit that travels the full length of its distal tubular member. The slit can accommodate the insertion and removal of various interventional devices from the tubular member, such that the support catheter can be coupled to the interventional device within the blood vessel after the interventional device has been inserted. When the support catheter is no longer needed, it can be simply withdrawn from the treatment site and decoupled from one (or more) interventional devices. Just as the configuration of the tubular member defining the slit can vary, the configuration of the slit can also vary to suit the user's needs, as further described herein. Although the distal tubular portion is referred to as the "member" throughout this document, it is understood that "member" refers to a longitudinal segment or portion, depending on the context, and is not limited to a single structure; rather, those skilled in the art who read this disclosure will understand that the claimed portion of the support catheter can be integral; single; composed of one, two or more components or materials; or a combination of these (longitudinally and / or axially oriented), and unless otherwise stated, the term "member" is not intended to limit the manner of construction of the device.

[0183] exist Figure 1AThe support catheter 100, depicted in a longitudinal section, includes a rapid exchange device 102 consisting of a distal sheath or tubular member 104 defining a longitudinal slit 106 and an angled proximal port 108 opposite a distal end opening 110. An inner lumen 111 defined by the tubular member 104 connects the proximal port 108 to the distal end opening 110. The support catheter 100 further includes a push member 112, such as a connecting wire or rod, which can be eccentrically coupled to the tubular member 104 at one end and coupled to an optional handle member 114 at a user-accessible, opposite proximal end outside the patient's body. The push member 112 can transmit thrust and pull forces applied by the user to slidably advance or withdraw the support catheter 100 during medical procedures without obstructing the lumen of the guiding catheter, allowing the interventional device to be advanced alongside the push member 112 and then advanced into the tubular member 104 via the proximal port 108. The longitudinal slit 106 can be adapted during medical procedures to load and unload the support catheter 100 onto and from various interventional devices. This adaptation can be achieved, with or without a loading tool, by expanding the width of the slit 106 by pushing the interventional device through it, as further elaborated and described below.

[0184] The handle component 114 can be formed of any one (or more) of materials that are user-gripable, such as polycarbonate. Together with the push component 112, the handle component 114 allows the user to push the tubular component 104 through the patient's vascular system (or body) to a target area. The size or shape of the handle component 114 may also prevent it from passing through a hemostatic valve that can be attached to the proximal end of a guide catheter through which the support catheter portions are inserted.

[0185] The length of the support catheter 100 can be varied. In some implementations (e.g.) Figure 1A In one embodiment depicted, the support catheter has a length of approximately 150 cm. In an additional embodiment, the length of the support catheter 100 may be less than approximately 50 cm, or may be any one of approximately 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm, 110 cm, 120 cm, 130 cm, 140 cm, 150 cm, 160 cm, 170 cm, 180 cm, 190 cm, 200 cm, or greater, or any length in between. The length of the support catheter 100 allows the tubular member 104 to reach the distal end or distal portion of the interventional device positioned at the vascular target site. Therefore, the length of the support catheter 100 may be approximately equal to or slightly less than the length of the interventional device. When suitable for use with a guiding catheter or sheath, the length of the support catheter 100 may be longer than the length of the guiding catheter or sheath.

[0186] The length of the tubular member 104 can also vary. In the example shown, the tubular member 104 is approximately 17 cm long. Additional examples may feature the tubular member 104 with a length of approximately 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, 11 cm, 12 cm, 13 cm, 14 cm, 15 cm, 16 cm, 17 cm, 18 cm, 19 cm, 20 cm, 21 cm, 22 cm, 23 cm, 24 cm, 25 cm, 26 cm, 27 cm, 28 cm, 29 cm, 30 cm, or greater, or any length in between. When suitable for use with a guiding catheter or sheath, the length of the tubular member 104 may be shorter than the length of the guiding catheter or sheath.

[0187] The proximal port 108 defines a proximal opening of the lumen 111. In the illustrated embodiment, the proximal port 108 includes an angled opening or cutout portion defined by an inclined wall, collar, or concave track (which extends from the actuating member 112 to a fully cylindrical portion of the proximal end 115 of the marked tubular member 104). In some embodiments, the proximal port 108 may be considered as part of or an extension of the actuating member 112 and / or the tubular member 104, particularly where the port 108 is angled, stepped, or otherwise inclined. In some examples, the proximal port 108 may be considered as a discrete component of the support conduit 100 joined or integrated between the proximal end 115 of the tubular member 104 or the distal end of the actuating member 112. The metallic or polymeric structure forming the proximal port 108 may have decreasing stiffness and increasing flexibility in a direction from proximal to distal to provide a gradual, flexible transition between the more stiff actuating member 112 and the generally more flexible tubular member 104.

[0188] The shape, angle, and configuration of port 108 can vary. For example, the near-end port 108 can define a smooth increase in circumference (in the distal direction) or a stepped increase in circumference defined by one or more platforms. Figure 1AA proximal port 108 is shown, having a generally non-sloping region separated by two sloping regions. In some examples, the proximal port 108 may include a full circumferential portion (which may form the proximal end of the tubular member 104), a semi-cylindrical portion, and an arcuate portion, each having any desired length, similar to the tubular portion of the guide extension conduit described in U.S. Patent No. 8,048,032. In other embodiments, the proximal port 108 may not be angled, but may define a blunt lateral opening perpendicular to the longitudinal axis of the tubular member 104. The proximal port 108 may have one or more slopes, or no slope (i.e., generally vertical), and may have any desired one or more angles.

[0189] like Figure 1B As shown in the plan view, the support catheter 100 may also include at least one radiopaque marking band 116 within the tubular member 104 to enable visualization and tracking of the catheter within the patient's vascular system. In some embodiments, the support catheter 100 or a portion thereof, such as the distal tubular member 104, may be formed of a radiopaque material. The actuating member 112 may also include radiopaque markings or depth markings.

[0190] Figure 1B A plan view of the proximal port 108 is also provided, showing a complete circumferential portion 118, a portion 120 greater than 180°, and a portion 122 less than 180°. The portion 120 greater than 180° may, for example, include a structure forming a circumference of approximately 300° of the tubular member 104. The portion 122 less than 180° may, for example, include a structure forming a circumference of approximately 90° of the tubular member 104.

[0191] A partial side view of the pushing member 112 is shown Figure 1C In some embodiments, the actuating member 112 may comprise multiple segments or portions with different stiffness and flexibility profiles to provide a desired combination of thrust and vascular placement capability for supporting the catheter 100. In this particular embodiment, the actuating member 112 tapers distally, such that the distal portion 132 has a narrower diameter than the intermediate portion 134, which in turn has a narrower diameter than the proximal portion 136. Alternatively, the actuating member 112 may have a generally uniform thickness and / or cross-sectional shape along its length. Alternatively, the distal portion of the actuating member 112 facing or adjacent to the tubular member 104 may be tapered, narrowed, and / or have a cross-sectional shape different from the cross-sectional shape of one or more portions of the actuating member 112 approaching or adjacent to the region of the tubular member 104.

[0192] To effectively propel the tubular member 104 of the supporting catheter 100 through the patient's vascular system, while preventing vascular obstruction and allowing various interventional devices to pass alongside the propulsion member 112, the propulsion member 112 may include a flexible rod, a wire, or a tubular element with a relatively small cross-sectional diameter or other dimensions. Examples may include a propulsion member 112 consisting of at least one segment (composed of wire only) and / or a wire and another segment (composed of a thiopanthus tube with an optional thiopanthus tube cap). Embodiments may also include at least one segment of a thiopanthus tube composed of a wire segment coiled into a coil. For example, the propulsion member 112 may include a proximal portion formed of a thiopanthus tube-coiled wire adjacent to a wire-only segment extending to and optionally beyond the proximal end 115 of the tubular member 104. Solid steel or nickel-titanium alloy core wires and solid core wires wrapped in smaller wire coils or braids may also be used. Alternatively, the actuating member 112 may have one or more gaps along part or all of its length, which may be discrete, discontinuous, or continuous, either wholly or partially. Typically, the actuating member 112 may comprise an elongated solid filament or rod of constant or varying dimensions and may comprise polymeric or metallic materials such as high-tensile stainless steel (e.g., 304V, 304L, or 316LV), mild steel, nickel-titanium alloy, nickel-chromium-molybdenum alloy, nickel-copper alloy, nickel-tungsten alloy, or tungsten alloy. The actuating member 112 may be coated with a hydrophilic, silicone, or other anti-friction material. The actuating member 112 may also be made of a thiocyanate tube; where the interior of such a tube is open at both ends and along its length, making the interior too small to allow passage of a balloon or stent catheter.

[0193] exist Figure 1C In the example shown, the distal portion 132 of the actuating member 112 has a cross-sectional diameter of approximately 0.006 inches, the intermediate portion 134 has a cross-sectional diameter of approximately 0.008 inches, and the proximal portion 136 has a cross-sectional diameter of approximately 0.018 inches. The aforementioned cross-sectional diameters are not limiting, as the cross-sectional diameter along the actuating member 112 can be in a range of approximately 0.001 inches to approximately 0.03 inches or greater. Any suitable one or more diameters may be used without interfering with the function or operation of the support conduit 100.

[0194] The length of the actuating member 112 may vary in part depending on the length and configuration of the support conduit 100, as the actuating member 112 may be attached at least to the proximal end of the tubular member and may extend proximally from the attachment to an optional handle member 114. The actuating member may be at least partially embedded within or coupled to at least a portion of the tubular member 104. Figure 1CThe example shown has a length of approximately 146 cm, such that the actuating member 112 spans almost the entire length of the supporting catheter 100. In additional examples, the actuating member 112 may extend only to or near the proximal end 115 of the tubular member 104. In various embodiments, the length of the actuating member 112 may be less than approximately 50 cm, or any one of approximately 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm, 110 cm, 120 cm, 130 cm, 140 cm, 150 cm, 160 cm, 170 cm, 180 cm, 190 cm, 200 cm, or greater, or any length in between. In specific, non-limiting embodiments, for example, for deployment in a coronary artery, the actuating member 112 may have a length of approximately 95 cm, and the tubular member 104 may have a length of approximately 15 cm. According to this embodiment, the inner diameter of the tubular member 104 can be fitted onto a 4F to 4.5F conduit and the outer diameter can be fitted into a 6F guide conduit, wherein there is sufficient clearance between the outer diameter of the tubular member 104 and the inner diameter of the guide conduit, as discussed below.

[0195] Figure 1D It is along Figure 1A The AA line shows a cross-sectional side view of the support catheter 100, which shows the actuating member 112, the angled proximal port 108, and the distal tubular member 104. The distal tubular member 104 may have a generally circular cross-section defining an inner lumen 111, the size of which is adapted to accommodate various interventional devices.

[0196] Figure 1E Is Figure 1AThe image shows a magnified view of the distal portion of the distal tubular member 104, taken at detail A, which reveals the marking band 116 and the distal portion of the longitudinal slit 106. As shown, the slit 106 may include a straight portion 124 and at least one inclined or curved portion 126 at the distal end of the straight portion (relative to the longitudinal axis of the tubular member 104). In embodiments, the support conduit 100 may have a continuous straight slit or a slit that jogs radially at one or more locations. In some embodiments, the slit may jog near its distal end, for example, across the distal end of the tubular member 104 by 0.25 cm to 3 cm. This configuration of the slit 106 facilitates guiding the support conduit 100 through tight bends in the vascular system by preventing the slit from opening before it is necessary. Although a jogged slit 106 is shown, a variety of other non-straight slit configurations can be used to achieve a similar purpose. In additional embodiments, for example, the tubular member 104 may have a spiral, zigzag, serpentine, or other irregular configuration, or a zipper-like longitudinal slit, to facilitate installation onto the interventional device while also providing increased resistance to accidental disengagement of the device.

[0197] The cylindrical wall defining the tubular member 104 may include an outer layer 128, and as... Figure 1F The inner liner 130, which defines the cross-sectional diameter of the tubular member 104, is shown in the cross-sectional side view. The outer liner 128 and the inner liner 130 may contain extrusions of various materials and may be reinforced with metal frame structures, braids, or coils, as further described herein.

[0198] In some examples, the support conduit 100 may have a nominal 4F size along the entire length of the tubular member 104, which may allow insertion of such a conduit via 5F, 6F, 7F, or 8F guide conduits. The diameter and overall design of the tubular member 104 may be made in smaller or larger diameters, depending on the end use and indication. Figure 1F The tubular member 104 shown has an inner diameter of 0.052 inches and an outer diameter of 0.068 inches. Generally, the size and shape of the inner lumen 111 of the tubular member 104 are suitable for accommodating one or more interventional devices through which they pass. In some examples, the inner diameter of the inner lumen 111 of the tubular member 104 is no more than about 1F smaller than the inner diameter of the inner lumen of the guiding catheter / sheath through which the supporting catheter extends during the medical procedure.

[0199] Generally, the tubular member 104 may have external cross-sectional dimensions that allow the tubular member 104 to slide coaxially (i.e., in a tube-in-tube configuration, substantially on the same longitudinal axis, and allowing space between the tubes) into and through the guide tube. The following discussion applies to, for example, Figure 2BAs shown, the tubular member 104 is in contact with or very close to each other (e.g., within about 1 mm) when the longitudinal edges of the slit are touching or very close (e.g., within about 1 mm). For example, for a 6F guide catheter, the inner diameter of the tubular member 104 can be about the inner diameter of a 5F guide catheter, or any suitable desired diameter. In some embodiments, the inner diameter of the tubular member 104 can be no more than about 1 F smaller than the inner diameter of the guide catheter used with it. The difference between the inner diameter of the tubular member 104 and the inner diameter of the guide catheter relates to their respective wall thicknesses and the gap between the outer diameter of the tubular member 104 and the inner diameter of the guide catheter, where the gap should be sufficient to allow the tubular member 104 to advance within the guide catheter. For example, the gap in the cross-sectional diameter between the inner diameter of the guide catheter and the outer diameter of the tubular member 104 can be less than and / or about 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 range from about 0.002 to 0.003 inches or about 0.002 to 0.0035 inches. In some embodiments, the diameter gap between the outer diameter of the tubular member 104 and the inner diameter of the guiding conduit can be substantially continuous along the majority or most of the length of the tubular member 104, or the gap and / or difference between the inner diameter of the tubular member 104 and the guiding conduit can vary along the length of the tubular member 104; for example, in one embodiment, the distal portion of the tubular member 104 can be tapered. In various embodiments, guiding conduits of any diameter can be used. The length of the tubular member 104 can be substantially less than the length of the guiding conduit; however, the tubular member 104 can be designed to have any length, such as any one of about 6 to 45 cm, 10 to 35 cm, 14 to 25 cm, or 18 to 20 cm, or any other desired length, depending on the desired application. While the above discussion is provided in the context that the slit edges of the tubular member 104 are in contact with each other or very close (e.g., within about 1 mm), it should be understood that these examples also apply when the slit edges overlap, such as... Figure 2E As shown, there may or may not be an interventional device within the tubular member 104, and it should be further understood that these examples apply when the longitudinal edges of the slit are in an open, extended configuration due to the interventional device, such as... Figure 5D As shown.

[0200] The optional marking band 116 of the support catheter 100 is shown. Figure 1G and 1H middle, Figure 1I The transverse sectional view shows an optional arrangement of the marking strip 116 relative to the distal tubular member 104. Figure 1GThis is a side view of the marking strip 116, showing its variable length L. In some embodiments, the length L of the marking strip 116 can be about 0.04 cm. As mentioned above, the tubular member 104 itself can contain a radiopaque material, such that it does not contain a separate marking strip. Other embodiments (such as the embodiment shown) include one or more discrete marking strips having a defined length, which can be less than or about 0.01 cm; or any length, or in between, about 0.02 cm, 0.03 cm, 0.04 cm, 0.05 cm, 0.06 cm, 0.07 cm, 0.08 cm, 0.10 cm, or longer.

[0201] The marking strip 116 may have a basic cylindrical configuration that extends circumferentially around the tubular member 104. Figure 1H The marking band 116 extends around the tubular member 104 at approximately 270°, leaving approximately 90° of the tubular member unmarked (plus or minus approximately 30°), through which a longitudinal slit 106 extends. In an embodiment, the marking band 116 may extend around the tubular member 104 at less than or greater than 270°, for example, across any one of approximately 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, 170°, 180°, 190°, 200°, 210°, 220°, 230°, 240°, 250°, 260°, 270°, 280°, 290°, 300°, 310°, 320°, 330°, 340°, 350°, 360°, or across any value in between.

[0202] like Figure 1H As further apparent, the cross-sectional thickness of the marking strip 116 can be smaller than the cross-sectional thickness of the wall of the tubular member 104. The inner diameter of the marking strip 116 can be approximately 0.054 inches, ±0.0002 inches, and the outer diameter can be approximately 0.056 inches, also ±0.0002 inches. The marking strip 116 can be symmetrical or substantially symmetrical with respect to the slit 106 (e.g., ±10°), as... Figure 1I As shown. The marking strip 116 may comprise platinum-iridium, platinum-tungsten, or alloys thereof. Alternatively, one or more marking strips may be formed by impregnating portions of the tubular member 104 with a radiopaque filler material (e.g., barium sulfate, bismuth trioxide, bismuth carbonate, tungsten powder, tantalum powder, etc.). The marking strip 116 may have any desired flexibility or stiffness.

[0203] The support catheter disclosed herein (including support catheter 100) can be formed of one or more biocompatible materials. Non-limiting examples of such biocompatible materials may include metals, such as stainless steel or alloys, such as nickel-titanium alloys, or polymers, such as polyether-amide block copolymers (Pebax®), nylon (polyamide), polyolefins, polytetrafluoroethylene, polyesters, nylon, polyurethanes, polycarbonates, or other suitable biocompatible polymers or composites and / or combinations thereof. Typically, different sections of the support catheter may be formed of materials different from other sections, and sections of the catheter may include multiple materials at different and / or specific locations. For example, the proximal extension rod / wire may be formed of a metal (e.g., stainless steel). Regarding the tubular component, a crucial material may comprise a thermoplastic polymer with embedded reinforcing materials, such as filaments, braids, or coils that may be metals or suitable polymers or other materials. Suitable polymer layer materials for the tubular component include, for example, polyamides, i.e., nylon, or Pebax®. The filaments may be braided, coiled, or otherwise placed on a polymer tubing liner under tension. A polymer sheath is then placed on top. After heating above the polymer's softening temperature and then cooling, the filament is embedded in the polymer. The lining and sheath can be the same or different materials. Suitable filaments for embedding in the polymer include, for example, flat stainless steel wire. The filament adds extra mechanical strength while maintaining an appropriate amount of flexibility.

[0204] Materials can be molded, extruded, etc., for example, using processing methods known in the art. Materials can be joined by softening one material and embedding another material within the softened material, and / or by using mechanical reinforcements, jigs, supports, etc. Medical-grade materials are generally commercially available and suitable for forming the structures described herein. Bending can be introduced into polymeric materials by softening and hardening the polymer on a bent mandrel or the like.

[0205] As shown in Table 1 below, the components included in the disclosed support conduit embodiments, such as the outer extrusion of the tubular member, the hysteresis tube, and the marking tape, are by way of example only and may be composed of one or more optional materials, including thermoplastic elastomers (e.g., HYTREL SSD 20% BaSO4), stainless steel (e.g., 304 SS), and alloys (e.g., Pt 10% Ir).

[0206]

[0207] In some embodiments, the expandable support conduit of this disclosure is characterized in that the proximal end of the tubular member has a larger diameter than the distal portion. For example, as... Figure 2A-2CAs shown, the support catheter 200 may include a distal tubular member 202 defining a longitudinal slit 204 extending from an angled proximal port 206 to a distal end opening 208. The tubular member 202 tapers distally, such that the proximal portion 210 has a larger diameter than the distal portion 212. Additionally or alternatively, it may be desirable for the proximal end 210 to open to a larger diameter than the rest of the tubular member 202. The tubular member 202 may taper from the proximal portion 210 to the distal portion 212 by any desired amount, for example, from just over 0 inches to about 1F to about 2F or more. For example, if the support catheter 200 is specifically configured for use with a 6F guiding catheter, the proximal portion 210 of the support catheter 200 may have a 5F outer diameter and the distal portion 212 may have a 4F outer diameter. The length of each discrete diameter portion may vary along the length of the tubular member 202. For example, the outer diameter may be approximately 5F at the proximal 90 mm of the tubular member 202, tapering from approximately 5F to 4F over the next 90 mm, and approximately 4F at its distal 90 mm. A support catheter used with a 7F guiding catheter may tape from 6F distally to 4F along its length. In some embodiments, the distal portion 212 of the support catheter may taper less, for example to 4.5F, or more, for example to 3.0 or 3.5F. However, in some cases, 4F may be the optimal balance between low profile / deliverability and reliable stent / balloon delivery system coverage. In some examples, it may be advantageous to taper the tubular member 202 such that its distal tip 214 is only slightly larger than the diameter of a guidewire (e.g., approximately 0.014 inches for coronary applications), which may have a solid structure or may have an internal structure, such as a hollow lumen or a core wire.

[0208] The outer diameter of the larger proximal portion 210 of the support catheter 200 can fit substantially tightly within the inner diameter of the guiding catheter or sheath through which the support catheter 200 is inserted, thereby maximizing the diameter of the lumen defined by the tubular member 202 and increasing the overall support provided by the support catheter 200, while also facilitating unobstructed passage of interventional devices and contrast agents. The lower profile and smaller diameter of the distal portion 212 of the tubular member 202 can facilitate the delivery of the guiding extension along narrow, tortuous blood vessels. Figure 2B and Figure 2C The cross-sectional view shows the larger cross-sectional diameter of the proximal portion 210 relative to the distal portion 212, as well as the longitudinal slit 204.

[0209] The configuration of the tubular member 202 and its longitudinal slit 204 can vary. In some embodiments, the slit 204 may be defined by the parallel juxtaposition of the opposing blunt edges or lips 216, 218 of the tubular member 202, such that the space between the opposing lips 216, 218 defines the width of the slit 204. In other examples, the lips 216, 218 may overlap in a pre-use (insertion) configuration prior to coupling with the interventional device, such as... Figure 2E As shown. According to this embodiment, during or after insertion of the interventional device through the tubular member 202, the lips 216, 218 of the slit 204 can overlap or return less. Figure 2D The non-overlapping configuration is shown.

[0210] For example, Figure 3A and 3B The support catheter 300 shown includes a tubular member 302 defining a longitudinal slit 304, which is configured to form and potentially expand until a variable-width gap is created between previously overlapping lips 306, 308. This expansion can occur when an interventional device is inserted into or removed from the lumen 310 of the tubular member 302. As the slit 304 of the support catheter 300 opens, the circumferential coverage of the interventional device is maintained sufficiently to retain the device within the lumen 310. This particular configuration allows the tubular member 302 to coil to a very small diameter when guided in tight blood vessels and / or when used to advance interventional devices with an outer diameter much smaller than the inner diameter of the tubular member 302. This configuration can also be advantageous in medical procedures involving direct tracking of the support catheter 300 on a guidewire, as the tight coiled configuration of the tubular member around the guidewire prevents the guidewire from slipping out of the lumen 310 of the tubular member 302 through the slit 304. In an additional example, the edges or lip of the slit may interlock, for example, in a keyed configuration, to prevent accidental removal of interventional devices inserted into the tubular member.

[0211] In some embodiments, the support conduit of this disclosure (e.g., any support conduit described herein) can be incorporated into a longitudinal slit that does not traverse the entire length of the tubular member. For example, Figures 4A-4C The support conduit 400 depicted includes a tapered tubular member 402 and a longitudinal slit 404 having a proximal end 406 away from the proximal port of the tubular member, such that the middle section of the tubular member 402 has no slit, as... Figure 4B As shown in the cross-sectional view, the proximal end 406 of the slit 404 may begin approximately at the beginning of the tapered portion of the tubular member 402. Figure 4C(As shown in the cross-sectional view) and extends through the distal end 410 of the tubular member 402, such that the slit 404 spans approximately two-thirds of the length of the tubular member 402. The length of the slit 404 can vary relative to the length of the tubular member 402. In some examples, the slit 404 may span at least about 50%, or at least about 60%, 70%, 80%, 90%, 95%, more than 95% of the length of the tubular member, or any length in between. This partial slit embodiment can be used in situations where the distal portion of a support catheter is deeply inserted into a reduced-size blood vessel, and the slit allows opposing lips to overlap and obtain a smaller tapered tubular member.

[0212] The non-limiting exemplary cross-sectional diameter of the tubular member disclosed before and after insertion of the interventional device is in Figures 5A-5D As depicted in the text. For example... Figure 5A As shown, the 5F tubular member 500a may have an outer diameter 502a of about 0.067 inches and an inner diameter 504a of about 0.056 inches. Figure 5B The 4F tubular member 500b shown has an outer diameter 502b of approximately 0.053 inches and an inner diameter 504b of approximately 0.046 inches. When an interventional device 506 is inserted through the 5F tubular member 500a, the slit 508a defined by the tubular member 500a can maintain the same or substantially the same width. Insertion of the same interventional device 506 through the tubular member 500b of the 4F catheter can cause an expansion of the width of the slit 508b of the catheter. The degree of expansion can vary depending on the number and cross-sectional dimensions of one (or more) interventional devices and / or the material composition of the tubular member. Figure 5D In the example shown, the reception of the interventional device 506 can cause the slit 508b of the 4F tubular member 500b to expand until it surrounds approximately 80% of the circumference of the interventional device 506. In other embodiments, the remaining circumferential coverage of the tubular member after insertion of the interventional device can vary within the range of approximately 50% or more, such as any one of approximately 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or any value between these ranges. Primarily due to the circumferential strength of the tubular member, the circumferential coverage of the interventional device provided by the surrounding tubular member after insertion is sufficient to retain the interventional device within the lumen defined by the tubular member. The remaining coverage is also sufficient to effectively transmit (from the support catheter to the interventional device) the thrust applied to the proximal end of the support catheter.

[0213] Additionally or alternatively, the support catheter of this disclosure (e.g., any support catheter described herein) may be characterized in that the distal end of the distal tubular member is more flexible than the proximal end, such as... Figure 6As shown, this can improve the maneuverability of the catheter within a patient's vascular system. As illustrated, the support catheter 600 may include a longitudinal slit 602 spanning at least a portion of a distal tubular member 604, which includes a distal portion 606 that is softer than a proximal portion 608. The distal portion 606 may be made of a polymer with a hardness of about 25D to about 63D (e.g., HYTREL, Nylon 12, or Pebax). The proximal portion 608 may be made of a polymer with a hardness of about 63D to about 72D (e.g., HYTREL, Nylon 12, or Pebax).

[0214] The number of segments with different hardness along the tubular member can vary, ranging from, for example, two, three, four, five, or more segments. Additional embodiments may include a tubular member having a soft or medium-hardness polymer from its proximal end to its distal end, followed by a harder polymer, and then another soft or medium-hardness polymer. In some embodiments, the hardness may vary substantially seamlessly and continuously along the length of the distal tubular member 604, making it impossible to definitively depict discrete regions with uniform hardness. In some embodiments, the transverse section of the distal tubular member may include materials with different hardness values. For example, viewed from a transverse cross-sectional perspective of the tubular member, the bottom of the circular section may be made of a polymer softer than the top of the circular section (including the slit location) to resist unintended deformation along each side of the slit. The tubular member 604 may have circumferential strength sufficient to resist unintended opening along the slit 602 as the tubular member 604 is advanced through bends and turns within the vascular system.

[0215] Regarding flexural modulus, embodiments of the support conduit may comprise, starting from the distal end: a first portion having a flexural modulus of approximately 13,000 PSI ± 5,000 PSI, a second portion having a flexural modulus of approximately 29,000 PSI ± 10,000 PSI, a third portion having a flexural modulus of approximately 49,000 PSI ± 10,000 PSI, and a fourth portion having a flexural modulus of approximately 107,000 PSI ± 20,000 PSI. Any amount of stiffness may be used along the length of some or all of the portions of the device, as will be apparent to those skilled in the art based on reading this disclosure.

[0216] In another embodiment, the distal tip of the tubular member may be tapered and flexible, allowing it to fold back into the lumen of the distal portion of the tubular member when interacting with the interventional device. This folding back of the distal tip can increase the support provided by the support catheter for the interventional device, which may be advantageous after the device has reached its target site. Therefore, proximal folding of the distal tip can reflect a shift in the primary function of the support catheter from catheter manipulation assistance to interventional device support. Embodiments may also include a flexible, tapered distal tip configured to fold back onto the outer surface of the distal portion of the tubular member.

[0217] In some embodiments, the expandable support conduit of this disclosure (e.g., any support conduit described herein) can incorporate a longitudinal slit whose cross-sectional width varies along the length of the tubular member. Specific examples may include a longitudinal slit that forms or incorporates one or more enlarged incision areas, such as... Figure 7 As shown in the non-limiting example, the illustrated support catheter 700 includes a distal tubular segment 702 opposite an optional handle 704, with a push member 706 positioned therebetween. A longitudinal slit 708 defined by the tubular member 702 includes a first incision region 710a adjacent to a second distal incision region 710b, with narrower regions 712a, 712b, and 712c positioned therebetween. The support catheter 700 can better facilitate clamping of the support catheter onto an interventional device. Embodiments may feature one incision region or more than two (e.g., four, five, six, or more) incision regions.

[0218] In some embodiments, the expandable support conduit of this disclosure (e.g., any support conduit described herein) can incorporate a “notched” slit that is fabricated to extend less than 100% through the wall of the distal tubular member, as described by Figure 8A , 8B As shown in the non-limiting example of 8C, the support conduit 800 includes a distal tubular member 802 with a longitudinal slit 804. Figure 8BA transverse sectional view of the distal tubular member 802, depicted along line AA, shows the wedge shape of the slit 804, which does not extend through the wall of the tubular member 802 into the inner lumen 806, thus keeping the inner surface of the tubular member 802 completely intact. By activating the slit without extending through the entire wall, the user may be able to use the support catheter as with currently commercially available support catheters (directly loaded onto the guidewire, or using the distal end of the guidewire, or reverse-loaded onto the inserted interventional device before the interventional device is introduced into the guiding catheter). The notched slit allows the support catheter to function similarly to currently commercially available support catheters, but unlike currently commercially available support catheters, it is removed by tearing open the slit and peeling the tubular member off the interventional device after it is no longer needed. Additionally or alternatively, a support catheter with a perforated slit can be used in a similar manner. Figure 8C An interventional device 808 is shown removed from the distal tubular member 802 of a support catheter 800 via a slit 804 that can be torn in a proximal-to-distal direction during separation of the support catheter 800 and the interventional device 808. In some examples, it may be necessary to place a support catheter 800 with a notched slit 804 prior to the interventional device 808. In the case of using a notched slit, the fragile, intact, membranous portion of the tube may be on the inner surface, outer surface, or both of the tube. Alternatively, the slit may be a series of perforations. When the fragile, intact portion of the tube is on the outer wall, it can be formed by molding the tubular portion onto a mandrel having a suitably shaped ridge formed longitudinally along the length of the mandrel, such that when the tubular portion is molded onto the ridge, the ridge leaves a notch along the length of the interior of the tubular portion.

[0219] The embodiments of the support conduit disclosed herein may be characterized by a tubular member defining at least one side port. For example, such as Figure 9 The illustrated support catheter 900 includes a proximal actuation member 901 and a tubular member 902. The tubular member 902 defines a distal end opening 904, a proximal port 906, and a lateral port 908. In addition to preventing backflow, the support catheter 900 can also deflect interventional devices (such as the illustrated guidewire 910) into target branch vessels within the patient's vascular system, as further described in U.S. Patent No. 10,173,029.

[0220] The size and shape of the side port 908 facilitate the withdrawal of the distal tip 912 of the interventional device. In some examples, the longitudinal length of the side port 908 is longer than the diameter of the guidewire (e.g., at least twice). At least a portion of the tubular member 902 may have a stiffness value approximately equal to or greater than that of the interventional device 910 to support the device when it is pushed through the side port 908. The tubular member 902 may have sufficient flexibility to open and close the interventional device 910, while also having sufficient stiffness to remain above the device 910 when the tubular member 902 is pushed into place within the blood vessel. The longitudinal slit 914 may be formed with overlapping segments, intersecting segments, and / or various locking segments.

[0221] In a specific example, the side port 908 has a longitudinal length of approximately 8 mm. The length of the tubular member distal to the side port can be approximately 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm or longer, or any length in between. The support conduit 900 may have one or more bends that deflect the side port 908 from the longitudinal axis of the tubular member 902 that extends from the proximal port 906 to the distal end opening 904.

[0222] In some embodiments, according to aspects of this disclosure, adding slits to the tubular element supporting the conduit may require altering the co-extrusion of the metal braid or coil in the distal tubular portion. Furthermore, the annular marking strip used in some embodiments described herein may be replaced with a non-transparent marking strip.

[0223] This disclosure envisions a variety of catheter construction options. One or more forms of the aforementioned support catheters can utilize some or all of these construction methods. In some embodiments, the distal tubular member of the support catheter can be extruded without metal braiding or coil reinforcement. According to this method, the polymer used to form the tubular member can be recirculated on top of the inner tubular liner (polymer or lubricant, such as PTFE). The polymer hardness can vary along the axis of the support catheter, with the segment having the lowest hardness typically near the distal tip (e.g., as shown in the image). Figure 1A , 1B (As shown in the non-limiting example of 6). Additionally, a smooth coating (e.g., a hydrophilic or silicone coating) can be applied to the inner and / or outer surfaces of the tubular member to reduce friction during use. As described above, by loading the polymer with a radiopaque agent such as bismuth subcarbonate or barium sulfate, at least a portion of the supporting conduit can be made radiopaque (visible under X-rays), and / or a slit-marking band with suitable flexibility can be used, wherein the Pt-Ir mark contains a slit and is typically embedded in the polymer near the distal tip (within 1 cm, preferably within 0.250 inches to 0.025 inches) (e.g., as shown in example 6). Figure 1E(as shown in the non-restrictive example).

[0224] It may be advantageous to: taper or flatten at least the distal portion of the actuating member, which in some examples may include metal or other suitable stiffness actuating shaft material; and to use welding, bonding, or adhesive to attach it to the tubular member and / or the interior of the reinforcing material and / or to a marking strip attached to the tubular member to improve the tensile strength of the assembly, for example, as in Figure 10 As shown in the support conduit 1000, the distal portion of the actuating member is connected to a marking band. In one embodiment, the support conduit 1000 includes a distal tubular member 1002 having a distal marking band 1004 defining a longitudinal slit 1006 opposite to the proximal portion of the actuating member 1008, which includes a wire. The actuating wire 1008 includes an elongated flat portion 1010 having a band-like cross-sectional shape that can extend to or near the distal end 1012 of the tubular member 1002. The support conduit 1000 further includes a proximal transition portion 1014, which may be defined by a crescent shape or a semi-tubular shape, and may be glued, welded, or otherwise secured to the proximal flat portion of the actuating wire 1016. By having a flat band-like shape and extending the length of the tubular member 1002, the flat portion 1010 of the actuating wire 1008 can provide a supporting “spine” for the tubular member 1002, as well as a larger surface area for securing the tubular member 1002. The flat portion 1010 can also provide tensile strength for the tubular member 1002.

[0225] In one embodiment, the tubular member supporting the conduit can be shaped to have a bend, for example, by heating and / or cooling in a bend shape to add the bend (e.g., as...). Figure 11 (as shown in the non-limiting example) to be shaped, or heated and cooled into a conical configuration (e.g., as shown in the non-limiting example) Figures 4A-4C (As shown). Figure 11 The curved catheter 1100 shown includes a distal tubular member 1102 having a curved portion 1104 and a longitudinal slit 1106. It also includes a proximal actuating member 1108 and an optional handle 1110. The slit may be inside the curve, which can prevent or stop the interventional device from accidentally exiting the lumen of the tubular member during use (e.g., when the tubular member is traversing a tortuous blood vessel). In different embodiments, multiple curved portions may be included at different points along the distal tubular member.

[0226] Tubular components supporting various catheters may have rounded edges at the distal and / or proximal ends to facilitate the insertion and withdrawal of interventional devices (e.g., such as...). Figures 12A-12C (as shown in the non-limiting example). In particular, the distal and / or proximal ends of the tubular member may have a rounded outer surface, a rounded inner surface, or a rounded inner and outer surface. Figure 12AThe circumferential wall 1202 of the distal end 1204 of the tubular member has, for example, a rounded outer surface 1206. Figure 12B The circumferential wall 1208 of the distal end 1210 of the tubular member shown has a rounded outer surface 1212 and an inner surface 1214. Figure 12C The circumferential wall 1216 of the distal end 1218 of the tubular member shown has a rounded inner surface 1220. Linings, translucent and / or metallic marking strips, as well as hydrophilic coatings, bends, and tapers are optional additional configurations that can be used in combination or not at all in this and all design configurations. Edges can be rounded by heating, material removal, end self-folding, adding material (different or the same), or other methods.

[0227] In some alternative embodiments, the distal tubular member supporting the conduit may comprise one or more polymer layers and reinforcing members, such as braids or coils, such that the tubular member includes layered circumferential walls. In some embodiments, the braid (or coils, longitudinal supports, or other reinforcing layers or one or more materials) may be loaded onto the liner and reflowed with an external polymer, such that the braid (or other reinforcement) is encapsulated. The assembly is then cut open, as... Figure 13A As generally shown in the longitudinal sectional view. The support conduit 1300 includes a distal tubular member 1302 formed according to this embodiment. The tubular member 1302 defines an inner lumen 1303 and the support conduit 1300 includes a pushing member 1304 adjacent to the distal tubular member 1302. The braided layer 1306 of the tubular member 1302 is enclosed within an inner liner 1308 and an outer polymer 1310, as... Figure 13B A magnified view of detail A shows more detail. The inner liner 1308 may be a polymer layer composed of or coated with silicone, polytetrafluoroethylene (PTFE), or another lubricating material to provide a smooth surface for the received interventional device. The outer polymer 1310 may be a polymer layer composed of one or more flexible materials (e.g., polyurethane, polyethylene, or polyolefin) whose hardness decreases sequentially along the length of the tubular member, and may be coated with a friction-reducing material (e.g., a hydrophilic or silicone material) to facilitate insertion and traceability through the vascular system and guiding catheter or sheath. Braided layers may include, for example, stainless steel or platinum alloys and may extend along at least a portion of the tubular member between the polymer layers. Any suitable polymer, metal, compound, or other suitable material, or combination thereof, may be used to support any desired component, aspect, or one or more portions of the catheter, as will be understood by one of ordinary skill in the art upon reading this disclosure.

[0228] Figure 13C The side view shows the longitudinal slit 1312 of the catheter 1300, and Figure 13DA magnified view of detail B is provided, showing one edge 1314 of the slit 1312 and revealing a cross-section of the braided layer 1306 exposed when the tubular member 1302 was flush-cut to form the slit 1312.

[0229] Figures 14A-14D A process 1400 for manufacturing braided catheters using at least one mandrel is described. (Example) Figure 14A As shown, process 1400 may involve inserting a first mandrel 1402 through a conduit 1406 opposite a push member 1408 into a preliminary slitless distal tubular member 1404. The distal tubular member 1404 comprises a first polymer layer 1410, which has been recirculated over a cylindrical braid 1412 and an inner liner 1414, all defining an inner lumen with a diameter smaller than the target diameter of the final distal tubular member. The distal tubular member 1404 is then cut open and loaded onto a larger second mandrel 1416, which opens a slit 1418. A second polymer outer layer 1420 is then recirculated onto the braid 1412 to encapsulate the braid and cover the slit 1418, as... Figure 14C As shown. Then cut the distal tubular member 1404 again, as shown. Figure 14D As shown, this forms the final slit 1422. An optional objective for all embodiments is to ensure that no sharp metal braid edges protrude through the polymer surface. It may be advantageous to taper the metal pushrod shaft and attach it to the braid and / or marking tape to improve the tensile strength of the component.

[0230] Alternatively, non-metallic materials can be used instead of metallic braids or coils, such as layers of woven polyester or carbon fiber (or similar materials). According to this embodiment, the slit can be cut through the tube (including through the polyester or carbon fiber layers).

[0231] In other embodiments, a metal “strip” or “coil” is added to the distal tubular member in place of or as a supplement to the metal braid. For example, Figure 15A A support conduit 1500 is shown, comprising a distal tubular member 1502 having a metal strip or coil 1504 surrounding an inner liner 1506. A distal marking strip 1508 is also included in the tubular member 1502. One or more proximal metal collars may be attached to the strip or coil. Figure 15B The perspective view also shows the longitudinal slit 1510 of the tubular member 1502 and the metal strip or coil 1504 exposed at the edge of the slit.

[0232] In other embodiments, the stainless steel tubing can be patterned to provide flexibility and then reflowed into the tubular assembly. This pattern can be stacked end-to-end and co-extruded. The metal structure can be cut such that it extends approximately 80-90% of the circumference around the distal end of the tube, allowing longitudinal slits to be added to sections lacking metal structure. While this production method may be slightly more complex than adding metal braid, it offers several potential benefits. For example, laser-cutting supports from 316 SS tubing using this technique can be relatively inexpensive. Many cutting patterns can be used to form the tubular assembly, including the option of adding a “spine” to the extruded tubular assembly. The flexibility of the tube can be varied along its length by having a row of support-like frames with different patterns, by varying the support (tube) thickness, or by varying the support width. Other components, such as distal marking strips and cuffs and segments (used to attach to the push wire at the proximal end), can be laser-cut as part of their respective patterns. When a row of patterned metal structures is stacked together, the patterns can be designed to be interdigitated and aligned. Different alloys, such as cobalt-chromium or platinum-chromium, can be used for some or all of the support to increase transmissivity linearity. One such design creates radial flexibility while preventing longitudinal compression and / or elongation. Non-limiting examples of optional patterned tubes are shown in... Figure 16A-16J The view is provided and described below.

[0233] Figures 16A-16C A support conduit 1600a is shown, having a distal tubular member 1602a composed of a ladder-shaped metal frame 1603a defined by a plurality of parallel ribs 1604a and interlaced gaps 1606a. A longitudinal "spine" 1607a spans the length of the frame 1603a, is integral with and connects to the fork 1604a. Figure 16A Perspective and Figure 16C As shown in the plan view, the distal end 1608a of frame 1603a can have a larger surface area than each of the individual forks 1604a to be particularly suitable for placing marking tapes, etc. The proximal end 1610a can be attached to or integrally formed with another frame having the same or different patterns. The slit 1612 of the distal tubular member 1602a... Figure 16B It can be seen in the transverse cross-sectional view. In some embodiments, the slit 1612 may be positioned approximately opposite the spine 1607a.

[0234] Figure 16DA serpentine frame 1603b is shown, which can be used to form the distal tubular member supporting a conduit in a similar manner. The serpentine frame 1603b may be defined by a series of longitudinal metal segments 1604b connected by lateral metal segments 1606b, which reach a apex, for example, at a distal end 1608b having a wide surface for integrating a marking band. Like frame 1603a, frame 1603b may be stacked with another frame at its proximal end 1610b.

[0235] Figure 16E A configuration of a support-like metal frame 1603c, which can be cut from a metal tube and used for a tubular member, is shown. The frame 1603c includes a series of box-shaped segments 1604c, each defining a central aperture 1606c. A series of relatively short longitudinal segments 1608c connect the box-shaped segments 1604c and provide the longitudinal “spine” of the frame 1603c. The pattern of the frame 1603c can be repeated to extend the longitudinal dimension of the tubular member formed therefrom, and / or the frame 1603c can be attached end-to-end to one or more additional frames to form an elongated tubular member composed of a series of individual frames.

[0236] Figure 16F The support-like frame 1603d shown also defines a series of box-like structures 1604d, but with lateral gaps 1606d between them. The successive gaps 1606d alternate between openings on the left or right sides of the structure 1603d relative to the orientation of the plan view shown.

[0237] Figure 16G Five additional examples of scaffold-like frames that can be used to form tubular members supporting conduits according to this disclosure are shown. The specific configuration of each frame can vary, and as... Figure 16G Clearly, the frame may include a series of repeating features that together define the monolithic structure. The frame may include or lack a distinct vertebral feature that extends substantially parallel to the longitudinal axis of the resulting tubular member.

[0238] Figure 16H-16J An embodiment of a scaffold-like frame incorporating interdigital features is shown. Figure 16H The frame 1603e shown includes a series of support-like segments 1604e arranged in a row. The segments 1604e are connected via interdigitated features 1606e aligned with the support-like segments 1604e. Figure 16I A perspective view of the distal portion of the distal tubular member 1602a is shown, which consists of a frame 1603e formed after the frame is rolled into a cylindrical shape. The gap 1607e left between the opposite lateral ends of each frame segment 1604e provides space for the subsequent formation of longitudinal slits. Figure 16JThis is an enlarged view of segment 1604e of frame 1603e, showing the first interdigital member 1608e opposite to the complementary interdigital member 1610e. To stack two or more segments 1604e in series, the first interdigital member 1608e can be inserted between the two parallel forks 1612e, 1614e constituting the complementary interdigital member 1610e.

[0239] Figure 16K Another configuration of a patterned frame 1603f, which can be used to form the distal tubular member of a support catheter, is shown. Frame 1603f includes opposing rounded ends 1604f, which together resemble a coiled wire or spring. These overlapping ends prevent the interventional device from accidentally dislodging through the longitudinal slit of the support catheter. Frame 1603f, through its non-overlapping slit sides, can also increase or maximize the inner diameter of the tubular member formed therefrom, unlike frame designs characterized, for example, by overlapping sides of the longitudinal slit. Figure 16K Design and Figure 16D The design is similar because it can be a continuous material (or discontinuous depending on the case), but it can be formed from wires arranged in a serpentine configuration, or cut or formed from nylon or other polymeric materials and then wrapped, folded or otherwise formed into a distal tubular member.

[0240] In some embodiments, the support conduit of this disclosure can incorporate one or more metallic fracture bands with any desired flexibility (or stiffness) along the entire length of the distal tubular member, for example, as Figure 17 As shown. The support conduit 1700 includes a distal tubular member 1702 composed of a plurality of steel strips 1704 embedded within an outer polymer layer 1706 radially surrounding an inner liner 1708. The strips 1704 may comprise radiopaque materials such as platinum-iridium, steel (e.g., 316 SS), or combinations thereof to ensure visibility in some areas and greater clamshell (radial) force in others. Applying the metal strips to the tubular member 1702 improves its radial force (thus ensuring the tubular member resists bending or kinking) and biases the slit 1710 into a closed configuration. By adding one or more strips 1704 along the length of the tubular member 1702, the manufacturer can advantageously control the areas requiring more radial force or force to maintain slit closure.

[0241] As further disclosed herein, the actuating component may be contained within the support conduit, for example... Figure 18AThe support conduit 1800a depicted herein includes a distal tubular member 1802a and a push rod 1804a. The push rod 1804a may typically be metal, polymer, or other suitable stiffness structure, or a combination thereof, integrally formed with and / or connected to the distal tubular member 1802a, and may optionally include one or more features described in more detail herein.

[0242] The cross-sectional shape of the push rod 1804a can be approximately circular. Figure 18B ), oval ( Figure 18C ), square ( Figure 18D ),rectangle( Figure 18E ), crescent concave ( Figure 18F The plunger 1802a can be either flat (18G) or curved (18G). One possible goal is to allow sufficient force for actuation while still allowing the tubular member 1802a to be flexible enough to follow bends and turns through various blood vessels. Another goal may be to allow as much cross-sectional space as possible between the outer diameter of the interventional device and the interior of the guiding catheter. The cross-sectional shape of the plunger 1804a can vary along its length; for example, the plunger 1804a can be rounded at the proximal end (e.g., 18G). Figure 18B (as shown) and the distal portion is concave (as shown) Figure 18F (As shown). Other configurations and combinations can be used (e.g., one or more parts of the push rod 1804a can be as follows according to...). Figure 18H (Discussion configuration).

[0243] Figure 18H Another potential cross-sectional shape of at least a portion of the actuating member is shown, the proximal portion of which is shown together with the guide conduit 1802b. The cross-sectional shape of the actuating member 1804b shown may be defined by an arcuate first surface 1806b and a second surface 1808b positioned opposite the first surface. The arcuate first surface 1806b may have an outer curvature matching the inner surface 1807b of the guide conduit. The second surface 1808b may be flat or substantially flat and may be furthest from the first surface 1806b at its center point. The two arcuate surfaces 1810b, 1812b connect the first and second surfaces. As further described in U.S. Patent No. 10,751,514, the arcuate or curved shape of the first surface 1806b conforms to the inner surface 1807b of the guide conduit 1802b to provide smooth relative movement between the two components. The arcuate shape of the first surface 1806b may also increase or maximize the axial or columnar strength of the actuating member 1804b. In general, the shown cross-sectional configuration of the push member 1804b can increase the pushing force capability and torque control compared to a flat rectangular push member.

[0244] Figure 18IA perspective view of a support catheter 1800c is shown, the support catheter 1800c having a distal tubular member 1802c coupled to a push member 1804c at its distal end 1806c. Surrounding the push member 1804c is a removable support member 1808c, which may include a longitudinal slit 1810c extending along its length. The slit 1810c may be formed to be resiliently closed such that it can be forcibly pried open to remove the removable support member 1808c from the push member 1804c. The distal end of the removable support member may include a stop or lip member 1812c, which may include a substantially soft, resilient, or otherwise compressible material configured to affect the tubular member 1802c without damaging it during insertion of the support catheter 1800c into a blood vessel, as further set forth in U.S. Patent No. 10,953,197, the entire contents of which are incorporated herein by reference. In some embodiments, the actuating member may be at least partially attached to the distal tubular member of the supporting conduit using adhesive bonding, thermal bonding, welding, brazing, or the like. Typically, the tubular member and the actuating member may be coupled in a manner that provides a smooth transition therebetween. The arrangement or configuration of this coupling may vary. For example, the tubular member may include an opening formed in its peripheral wall, and the actuating member may be disposed within this opening. Inserting the actuating member into the opening can result in mechanical coupling between the members, and additional or alternative adhesives may be used.

[0245] In some implementations, the actuating member can alter the dimensions and / or properties (e.g., stiffness) of the region abutting with the tubular member. For example, it may be desirable to increase the flexibility of the actuating member and extend it into the wall of the polymer tubular member, such as... Figure 19A and 19B As shown in the view. Figure 19A The illustrated support conduit 1900a includes a tubular member 1902a and a pushing member 1904a. An embedded portion 1906a of the pushing member 1904a is embedded within the circumferential wall of the tubular member 1902a, radially separated from the longitudinal slit 1908a. The length of the embedded portion can vary, extending less than approximately 5% of the length of the tubular member 1902a, or any one of approximately 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or more, or any portion thereof.

[0246] exist Figure 19BIn the illustrated embodiment, the support conduit 1900b may further include a push member 1904b having a substantially flat portion 1906b radially separated from the longitudinal slit 1908b. The flat portion 1906b extends almost the entire length of the tubular member 1902b and terminates at a distally positioned marking strip 1910b. The flat portion 1906b of the push member 1904b may be directly attached to the marking strip 1910b or another metal part of the tubular member 1902b.

[0247] The actuating member can be attached to any of the aforementioned reinforcements located within the tubular member. Typically, it is desirable to attach the actuating member to the distal end of the tubular member opposite the slit; however, alternatively, it can also be attached in a manner that allows the actuating member to be on the same side of the slit or at a different radial location. For example… Figure 20A and 20B Perspective and transverse sectional views of a support conduit 2000, including a tubular member 2002 and a pushing member 2004, are shown. Near the proximal end of the tubular member 2002, the pushing member 2004 longitudinally splits to form a fork-shaped member 2005 composed of a first fork tooth 2006 and a second fork tooth 2008, both of which can extend and attach or embed within the tubular member 2002, thereby forming a first embedded fork tooth 2010 and a second embedded fork tooth 2012. Each embedded fork tooth 2010, 2012 can support one side of a longitudinal slit 2014 defined by the tubular member 2002. Figure 20BAs shown more clearly in the cross-sectional view, the first embedded fork tooth 2010 may be adjacent to one side of the slit 2014, and the second embedded fork tooth 2012 may be adjacent to the opposite side of the slit 2014, both forks being embedded within the outer polymer layer 2016 surrounding the liner 2018. Alternatively or additionally, the actuating member 2004 may be made of separate longitudinal members fused, bonded, or held or fixed together along the length of the actuating member 2004 until the actuating member 2004 is sufficiently close to the tubular member 2002 for individual attachment of the longitudinal members to the tubular member 2002. The length of each embedded fork tooth 2010, 2012 may vary. Typically, the integrity of the slit 2014 can be enhanced by increasing the length of the forks 2010, 2012 within the tubular member 2002. It should be noted that the slit in this embodiment can be used to further increase the force to keep the slit closed by means of material memory, by relying on magnetic force, or by mechanical interlocking features that ensure the two sides of the slit and / or gap actuating member can interlock together. In some embodiments, one or more reinforcing structures, such as braids, coils, and / or marking strips, can be attached to the embedded fork teeth 2010, 2012. The fork member 2005 can be configured to provide a radial closing force on the slit 2014 to prevent the slit from expanding undesirably. The cross-sectional shape and width of the actuating member 2004, which includes the fork teeth 2006, 2008, 2010, 2012, can vary. In some examples, all or at least a portion of the actuating member 2004 can have a flat and / or tapered cross-sectional configuration.

[0248] The actuating member may or may not have a handle member located on the proximal portion or end. Preferably, the handle member will have a larger diameter or other dimension than the actuating member alone. Alternatively, according to, for example... Figure 1A and 1B In a non-limiting embodiment, the handle member can be positioned to allow a working length of at least about 110 cm (the length from the distal tip of the tubular member to the starting point of the handle). In some embodiments, the push member may have at least one mark positioned along its axis that indicates to the user that once the mark approaches the proximal end of the guide catheter, the distal tip of the support catheter is close to the distal tip of the inserted guide catheter. In this embodiment, the mark may preferably be located about 100 to about 110 cm from the most distal tip of the support catheter, for example, as shown in the figure. Figure 21As shown, a support catheter 2100 consisting of a distal tubular member 2102 and a proximal actuating member 2104 is illustrated. The tubular member 2102 defines a longitudinal slit 2106, and the actuating member 2104 includes a marking 2108. An interventional device 2110 compatible with the support catheter 2100 is shown adjacent to it. The marking 2108 of the support catheter 2100 is positioned such that when the distal tip of the support catheter 2100 is aligned with the interventional device 2110, the marking 2108 is substantially aligned with the proximal end of the interventional device 2110 (which may be defined by the proximal end of the Luer connector / valve 2112).

[0249] Some aspects of this disclosure relate to various techniques and / or tools that can be used to load and unload the disclosed support catheter onto and from various interventional devices. It should be understood that one or more combinations of the loading / unloading features described herein may be used together in some examples. According to this disclosure, loading the support catheter refers to coupling the support catheter to the interventional device. Coupling may involve inserting the interventional device through a longitudinal slit in the tubular member of the support catheter into a lumen defined by the tubular member. Unloading the support catheter refers to decoupling the support catheter from the interventional device by removing the interventional device from the lumen of the tubular member of the support catheter via the longitudinal slit. Advantageously, the loading and / or unloading of the disclosed support catheter can be achieved without first removing the interventional device from the blood vessel. The loading tools described below facilitate the loading and unloading process.

[0250] Regarding the unloading method, as previously described, the expandable slit support catheter can be unloaded from the guidewire as follows: first, withdraw the interventional device from the guiding catheter, then withdraw the interventional device from the guidewire, and subsequently withdraw the expandable slit support catheter from the guidewire. Alternatively, the expandable slit support catheter and the interventional device can be removed simultaneously, or the support catheter can be removed from the interventional device while the interventional device remains fully or partially positioned within the guiding catheter.

[0251] A non-limiting example of the arrangement of these devices prior to the implementation of these technologies is provided by Figure 22A and 22B The view is shown. Figure 22A The illustration shows the distal end 2200 of the guidewire 2202, interventional device 2204, support catheter 2206, and guiding catheter / sheath 2208 positioned within a blood vessel 2210 during a medical procedure. The guiding catheter / sheath 2208 may surround the support catheter 2206, which may surround a portion of the interventional device 2204, which has been inserted onto the guidewire 2202. Figure 22BThe proximal end 2212 of the guidewire 2202, interventional device 2204, and support catheter 2206 is shown in position. The proximal end of the support catheter 2206 (which includes a portion of the push member 2214 and an optional handle 2216) protrudes from the proximal end of the access sheath 2218. The proximal end of the guidewire 2202 protrudes from the proximal end of the interventional device 2204 (which may include a proximal Luer connector or hub 2220).

[0252] In other embodiments, the longitudinal slit of the disclosed support catheter provides an additional option for unloading the support catheter from an interventional device (e.g., treatment delivery catheter shaft and / or guidewire) already in place in the guiding catheter and / or coronary artery. This is due to the large hub on the proximal end of some interventional devices, such as... Figure 23 As shown, the support catheter 2300 can be unloaded by peeling it from the side of the axis of the interventional device 2302 and / or guidewire 2304 through the longitudinal slit 2306 of the support catheter 2300. This can be accomplished by simply pushing the slit 2306 open and withdrawing the support catheter 2300 from the axis of the interventional device 2302 and / or guidewire 2304 until the components are completely removed. More specifically, it may be advantageous to remove the support catheter 2300 from the interventional device 2304 by pulling the tubular member 2308 and the pushing member 2310 of the support catheter 2300 away from the axis of the interventional device 2302, such that the axis of the interventional device 2302 first leaves the proximal portion 2312 of the slit 2306, and then continues removal from proximal to distal, resulting in complete removal when the distal portion 2314 of the slit 2306 is removed. This sequence can be performed on one or more forms of support conduits disclosed herein, including embodiments in which the slit initially does not cut through the entire wall of the tubular member (e.g. Figures 8A-8C In that case, by pulling first from the proximal end of the tubular member, the slit can tear through the entire wall of the tubular member until the interventional device can be removed, and the tear will travel distally until the support catheter is completely separated.

[0253] Figure 24A and 24B Two loading techniques that can be implemented using the disclosed apparatus are shown. For example... Figure 24A As shown, an expandable slit support catheter 2400a can be loaded onto the guidewire 2404a by stringing the distal tubular member 2404a onto the proximal end of the guidewire 2402a, advancing the tubular member 2404a via the hemostatic valve 2405a coupled to the guiding catheter 2406a, and moving the support catheter 2400a distally through the guiding catheter / sheath 2406a. This can be done if it is known in advance that a support catheter will be needed. Alternatively, and as... Figure 24BAs shown, the distal end of the interventional device 2408b and / or the treatment structure can be preloaded into the proximal end of the support catheter 2400b, and the assembly extends uniformly on the guidewire 2402b and through the guide catheter / sheath 2406b, which can be coupled to the proximal hemostatic valve 2405b, to the target location in the blood vessel.

[0254] In other implementations, the longitudinal slit provides additional options for loading an expandable slit support catheter onto an interventional device (e.g., balloon / stent delivery catheter shaft and guidewire) already in place in the coronary artery, such as via... Figure 25A and 25B The view shown illustrates a support catheter 2500a and a guidewire 2502a. The support catheter 2500a has a distal tubular member 2504a and a longitudinal slit 2505a that expands on the interventional device 2506a when the support catheter 2500a is pushed distally toward the guide catheter / sheath 2508a. Due to the large hub 2510a on the proximal end of the interventional device 2506a, the slit expands the support catheter 2500a, which must be loaded onto one side of the axis of the interventional device 2506a and / or the guidewire 2502a. This can be accomplished by simply pushing the slit 2505a open and advancing the expandable slit support catheter 2500a onto the axis of the interventional device 2506a and / or the guidewire 2502a until the components are completely within the tubular member 2504a. More specifically, it is advantageous to load the support catheter 2500a onto the interventional device 2506a by advancing the tubular member 2504a and the pushing member proximally, such that the axis of the distal end 2512a of the support catheter 2500a is first loaded onto the interventional device 2506a and advanced, thereby resulting in full loading when the proximal region of the slit 2505a is loaded. Note that this loading can be performed on both wire-on interventional devices, where the guidewire is positioned inside the interventional device from the tip to the hub, or on rapid-exchange interventional devices, where the guidewire is positioned inside the distal end of the interventional device but withdrawn and outside the proximal end. Figure 25B A support catheter is shown being loaded onto a rapid exchange device, such as an interventional device. The support catheter 2500b is being loaded onto a guidewire 2502b via a tubular member 2504b. The distal portion of the guidewire 2502b is inserted into a rapid exchange interventional device 2506b, which in turn inserts a guiding catheter / sheath 2508b.

[0255] Figure 25A and 25BOptional loading tool areas A and B are also shown. In some embodiments, a dedicated loading tool can be a useful aid for facilitating the process of loading a support catheter onto one or more interventional devices. Where provided, the loading tools of this disclosure facilitate clamping an expandable slit support catheter onto the axis of an interventional device (balloon, stent, etc.) and optionally onto a guidewire (for interventional devices with a rapid exchange design). The loading tools are designed to make loading quick and simple, and ensure that this operation can be performed by a single user. Generally, all forms of loading tools of this disclosure are designed to facilitate one or more of the following.

[0256] Some loading tools disclosed herein can facilitate alignment by providing an axial or coaxial track that introduces the lumen of the expandable slit-support catheter into the axis of the interventional catheter (and optionally the axis of the guidewire), such that all lumens and the axis are supported and introduced in similar planes. It may be advantageous to introduce the lumen of the expandable slit-support catheter into the axis of the interventional catheter such that the radial center of the lumen is aligned with the radial center of the axis. It may also be advantageous to introduce the lumen into the axis at an angle less than 90° but greater than 0°, for example, as... Figure 26 As shown, the support catheter 2600 approaches the interventional device 2602 at an angle α less than 90° in the direction of the arrow. The radial center A of the support catheter 2600 and the radial center B of the interventional device 2602 are preferably in the same plane to align the two devices and facilitate the loading process.

[0257] Implementations of the loading tool described herein may include various variations of axial or coaxial guideways. For example, the guideway may take the form of at least one loading structure, such as a channel, rod, or groove, to provide external support and guidance for supporting catheters and one (or more) interventional devices. Figure 27As shown, the loading tool 2700 may include a block or main body member 2702 defining a bifurcated channel 2704, which consists of a straight delivery channel 2706 intersecting an angled loading channel 2708. The former is configured to receive and guide one (or more) interventional devices, while the latter is configured to receive and guide a support catheter. The intersection 2710 of the two channels [where the support catheter is loaded onto one (or more) interventional devices] demarcates a proximal portion 2712 and a distal portion 2714 of the loading channel. In some embodiments, the delivery channel 2706 intersects the midpoint of the loading channel 2708 such that the length of the proximal portion 2712 is equal to or substantially equal to the length of the distal portion 2714. The angle α defined by the proximal side of the intersection 2710 between the delivery channel and the loading channel can vary, ranging from about 5° to about 85° or any angle in between, such as about 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75° or 80°.

[0258] For example, Figure 28A and 28B The loading tool 2800 shown includes a main body component 2802 defining a bifurcated channel 2804, which consists of a straight delivery channel 2806 and an angled loading channel 2808. The angle α defined by the intersection 2810 of the delivery channel 2806 and the loading channel 2808 is approximately 60°, but any suitable angle can be used. The loading channel 2808 includes a proximal portion 2812 and a distal portion 2814, as defined by the location of the intersection 2810.

[0259] like Figure 28B and 28D As further shown in the figure, the width of the main component 2802 wl It can be approximately 1.25 cm in length. l It can be approximately 2.5 cm, and the thickness... t It can be approximately 0.25 cm. The cross-sectional width of delivery channel 2806. w2 It can be approximately 0.04 cm to accommodate one (or more) interventional devices, and the width of the loading channel 2808... w3 It can be approximately 0.07 cm to accommodate the support catheter. Because the cross-sectional width of the support catheter can be larger than the combined cross-sectional width of other interventional devices, the width of the distal portion 2814 of the loading channel 2808 is... w4 It can be the same as or substantially the same as the proximal portion 2812, and is 0.07 cm in the illustrated embodiment.

[0260] like Figure 28C As shown, the depth of delivery channel 2806d1 It can be approximately 0.07 cm, while the depth of the distal portion 2814 of the loading channel 2808 is... d2 It can be smaller. Specifically, Figure 28E The enlarged view of detail A shown reveals that the delivery channel 2806 defines a grooved track 2816, which has a greater depth than the shallower, wider track 2818 of the loading channel 2808. (As shown) Figure 28E and 28F Further shown is the depth of the wider track 2818 of the loading channel 2808. d2 It can be approximately 0.015 cm shallower than the grooved track 2816 of the delivery channel 2806. Both the delivery channel and the loading channel can have variations in the arcuate profile shape. Furthermore, any suitable size can be used for this and other loading tools described herein.

[0261] Figure 29A and 29B A different view of another loading tool 2900 is provided, which includes a main component 2902 defining a bifurcated channel 2904, which comprises a straight delivery channel 2906 and an angled loading channel 2908, the former configured to receive and guide one (or more) interventional devices, and the latter configured to receive and guide a support catheter. The intersection 2910 of the two channels [where the support catheter is loaded onto one (or more) interventional devices] demarcates the proximal portion 2912 and the distal portion 2914 of the loading channel. The angle α defined by the proximal side of the intersection 2910 can vary and is approximately 30° in this particular embodiment. In an additional embodiment, the angle α can range from about 5° to about 85° or any angle in between, such as any one of about 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75° or 80°.

[0262] like Figure 29B and 29C As further shown in the figure, the width of the main component 2902 wl It can be 1.25 cm, length l It can be 2.5 cm, and the thickness of the main component 2902 is... t It can be 0.125 cm. The width of delivery channel 2906. w2 It can be approximately 0.04 cm to accommodate one (or more) interventional devices, and the width of the loading channel 2908... w3It can be approximately 0.07 cm to accommodate the support catheter. Because the cross-sectional width of the support catheter inserted into the loading channel 2908 can be larger than the combined cross-sectional width of other interventional devices inserted into the delivery channel 2906, the width of the distal portion 2914 of the loading channel 2908 is... w4 It can be the same as or substantially the same as the proximal portion 2912, and is 0.07 cm in the illustrated embodiment.

[0263] like Figure 29C and 29D As further shown, the depth of the delivery channel 2906 can be greater than the depth of the loading channel 2908. Figure 29D The enlarged view of detail A shows that the delivery channel 2906 defines a grooved track 2916, which has a greater depth than the shallower and wider track 2918 of the loading channel 2908. Both the delivery channel and the loading channel can have variations in an arcuate profile shape.

[0264] The length of the proximal portion 2912 of the loading channel 2908 can be approximately 1.287 cm, and the lengths of the distal portions 2914 of the delivery channel 2906 and the loading channel can both be approximately 1.25 cm. The length of each channel can vary and can depend at least in part on the angle α of the intersection point 2910.

[0265] Figure 30A and 30B A different view of another loading tool 3000 is provided, which includes a main body member 3002 defining a bifurcated channel 3004 composed of a straight delivery channel 3006 and an angled loading channel 3008. The intersection 3010 of the two channels delineates a proximal portion 3012 and a distal portion 3014 of the loading channel. In this particular example, the angle α defined by the intersection 3010 of the two channel portions is measured to be approximately 15° from the proximal side. In additional embodiments, the angle α can range from approximately 5° to approximately 85° or any angle in between, such as any one of approximately 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, or 80°.

[0266] like Figures 30B-30D As further shown in the figure, the width of the main component 3002 wl It can be approximately 1.25 cm in length. l It can be approximately 2.5 cm, and the thickness... t It can be approximately 0.125 cm. The cross-sectional width of the delivery channel. w2 It can be approximately 0.045 cm to accommodate one (or more) interventional devices, and the width of the loading channel...w3 It can be 0.08 cm to accommodate the support catheter. The width of the distal portion 3014 of the loading channel 3008. w4 It can be the same as or substantially the same as the proximal portion 3012.

[0267] Similar to loading tools 2800 and 2900, delivery channel 3006 defines a narrow, grooved track 3016, the bottom of which has a greater depth than the shallower, wider track 3018 of loading channel 3008. Figure 30F As shown in the cross-sectional view, the depth of track 3016 of delivery channel 3006 can extend about 0.01 cm below the bottom of track 3018 of loading channel 3008.

[0268] The length of the proximal portion 3012 of the loading channel 3008 can be approximately 1.223 cm, the length of the distal portion 3014 can be approximately 1.319 cm, and the length of the delivery channel 3006 can be approximately 1.19 cm. The length of each channel can vary and can depend at least in part on the angle α of the intersection point 3010.

[0269] like Figure 30C As further shown, both the proximal end portion 3020 of the delivery channel 3006 and the proximal end portion 3022 of the loading channel 3008 can be exposed on the proximal end portion 3024 of the body member 3002. Due to the small angle α between the proximal portions 3012 of the delivery channel 3006 and the loading channel 3008, the length of the intersection point 3010 is... 12 The length is significantly larger in this implementation scheme. 12 It facilitates smooth loading and unloading of the support catheter and one or more interventional devices.

[0270] Figures 31A-31D A view of another loading tool 3100 is provided, which includes a main body member 3102 defining a bifurcated channel 3104, this time consisting of a curved delivery channel 3106 and a curved loading channel 3108. The intersection 3110 of the two channels [where a support catheter is loaded onto one (or more) interventional devices] demarcates the proximal portion 3112 and the distal portion 3114 of the loading channel 3108. In some embodiments, the proximal portion 3116 of the loading channel 3108 may be straight or substantially straight, as may the distal portion 3118 of the loading channel.

[0271] like Figure 31B-31D As further shown in the figure, the width of the main component 3102 wl It can be approximately 2.0 cm in length. l It can be approximately 2.5 cm, and the thickness...t It can be approximately 0.125 cm. The cross-sectional width of the distal portion of the loading channel 3114. w2 It can be the same as or substantially the same as the cross-sectional width of the proximal portion 3112, which is 0.08 cm in the illustrated embodiment.

[0272] Figures 32A-32C A view of another loading tool 3200 is provided, which includes a body 3202 defining a bifurcated channel 3204 composed of a curved delivery channel 3206 and a curved loading channel 3208. The intersection 3210 of the two channels defines a proximal portion 3212 and a distal portion 3214 of the loading channel 3208. In some embodiments, the proximal portion 3216 of the loading channel 3208 may be straight or substantially straight, as may the distal portion 3218 of the loading channel.

[0273] like Figures 32A-32C As further shown, the proximal portion 3212 of the loading channel 3208 may include an internal lip or guide rail 3220 projecting into the lumen of the channel 3208, wherein, as the support catheter 3224 slides along the guide rail, it may maintain the longitudinal slit 3222 of the support catheter 3224 in an open configuration, ready to receive the interventional device at the intersection 3210. The cross-sectional width of the distal portion 3214 may taper gradually in the distal direction. In some embodiments, the taper may occur within approximately one inch of extension. This internal lip or guide rail 3220 may also be used on any loading tool, as described herein.

[0274] Figures 33A-33C A view of another loading tool 3300 is provided, which includes a main body member 3302 defining a bifurcated channel 3304 composed of a curved delivery channel 3306 and a curved loading channel 3308. The intersection 3310 of the two channels defines a proximal portion 3312 and a distal portion 3314 of the loading channel 3308. In some embodiments, the proximal portion 3316 of the loading channel 3308 may be straight or substantially straight, as may the distal portion 3318 of the loading channel. Any desired curvature, angle, straightness, or combination thereof can be used.

[0275] like Figures 33A-33CAs further shown, the proximal portion 3312 of the loading channel 3308 may include a track 3320, which includes a lip extending into the channel lumen. This lip may be an internal spherical lip or other suitable structure. A longitudinal slit 3322 of the support conduit 3324 may slide along the track 3320, thereby holding the slit 3322 in an extended position configured to facilitate reception of one or more interventional devices upon contact at the intersection 3310. The track 3320 may taper along the distal portion 3314 of the loading channel 3308 until it no longer protrudes from the inner wall of the channel. In some embodiments, a complete taper may occur within approximately one inch of the extension of the distal portion 3314 of the loading channel. Because the track 3320 is fitted within the support conduit, the maximum outer diameter of the track 3320 is at least slightly smaller than the inner diameter of the support conduit. In some examples, the outer diameter of the track 3320 may be approximately 0.05 inches. Including the protruding track 3320 can eliminate the need for quadrant 3326 of the main component, as is included in the loading tool described above.

[0276] The cross-sectional diameter of the channel can be approximately equal to or slightly larger than the outer diameter of the expandable slit support catheter and interventional device (optionally including guidewire and wire bundle features). Similarly, the internal support features can have an outer diameter similar to or larger than the inner diameter of the slit support catheter lumen (or larger, to facilitate slit opening). It may also be desirable to have a loading structure, such as an elongated shaft or rod, a tapered shape, and / or a wedge-shaped protrusion (other shapes may also be used), so that the support catheter can be easily loaded onto the loading structure, after which the longitudinal slit can expand as the slit tubular member approaches the axis of the interventional device, for example, as... Figure 34 As shown.

[0277] Figure 34 A loading tool 3400 is shown, comprising a main component 3402, which again features a delivery channel 3406 and a loading channel 3408 joined at an intersection 3410, which delineates a proximal portion 3412 and a distal portion 3414 of the loading channel 3408. The proximal portion 3412 of the loading channel defines an internal protrusion or wedge 3416 that is thinner at point A than at point B. In operation, the longitudinal slit of the supporting catheter expands as it advances along the internal wedge 3416 toward point B, such that the slit opens to be equal to or greater than the diameter of the axis of the relevant interventional device inserted through the delivery channel 3406.

[0278] Figure 35A loading tool 3500 is shown, comprising a main component 3502, which again features a delivery channel 3506 and a loading channel 3508 connected at an intersection 3510, which delineates the proximal portion 3512 and the distal portion 3514 of the loading channel 3508. As shown, the cross-sectional diameter of the distal portion 3514 of the loading channel 3508 tapers gradually in the distal direction to close the longitudinal slit surrounding the support catheter of the interventional device and tighten their coupling as the two components extend through the distal portion 3514 of the loading channel.

[0279] In one embodiment, the slot or channel of the loading tool may be larger at the intersection between the loading channel and the delivery channel, which can provide space for the support catheter to wrap around the interventional device in an unobstructed manner, for example, as Figure 36 As shown. The channel depicted by the loading tool includes a branching channel 3604, which has a delivery channel 3606 and a loading channel 3608 that converge at an intersection 3610. As shown, the diameter of the delivery channel 3606 at point B is smaller than the diameter of the distal portion 3614 of the loading channel 3608 at point A.

[0280] Figure 37 This is a perspective view of another loading tool 3700, this time characterized by an elongated body 3702 or rod defining a longitudinal gap 3704 configured to receive a support catheter. The body 3702 includes an arcuate wall 3706 defining a receiving space 3708 configured to receive one or more interventional devices. The unidirectional extension of the support catheter and interventional device along the length of the body 3702 facilitates coupling of the two components, as both extend beyond the body 3702 toward the treatment site. This configuration also facilitates removal of the loading tool from the guide extension spool.

[0281] Axial or coaxial guides can also take the form of shafts or rods that provide internal support and guidance, for example, Figure 38A The view is shown. The shaft or rod section can be circular, as shown, but it can also be non-circular (e.g., triangular, wedge-shaped, square, rectangular, elliptical, C-shaped, or any desired regular or irregular configuration or similar, or a combination thereof, such as...). Figure 38B-38G (As shown). Combinations of cross-sectional shapes can be contained within a single loading device. The cross-sectional shape can also vary along the length of the loading tool's channel or rod.

[0282] The loading tool disclosed herein can have a combination of loading structures. Embodiments may include at least one elongated rod, channel, and / or groove configured to receive and be adapted for axial or coaxial sliding of a tubular member supporting a conduit. Furthermore, the loading tool embodiments may include combinations of features such as channels, grooves, rods, wedges, elongated protrusions, tracks, or inner shafts / rods, specifically configured to open longitudinal slits supporting the conduit, for example, as... Figure 39 As shown, it depicts a loading tool 3900 having a combination of internal and external supports and guides (e.g., rods and slots). The loading tool 3900 includes a loading rod 3902 attached to a delivery channel or slot 3904. The delivery slot 3904 is configured to receive and guide one or more interventional devices, and the loading rod 3902 is configured to receive and guide a support catheter. The dimensions of the delivery slot 3904 and the loading rod 3902 allow for axial or coaxial sliding of the interventional device and the support catheter, respectively. In some embodiments, it may be advantageous to provide the loading tool 3900 as a multi-part, unassembled device. For example, it may be advantageous to allow the internal rod to be inserted into the distal end of the support catheter until its longitudinal slit opens, and then assemble this assembly into a body member or block defining one or more delivery slots.

[0283] Another optional feature provided by some loading tools of this disclosure is a feature for opening the slit of the support catheter. Functionality can be added to the tool to open the slit so that it can easily slide onto the axis of the interventional device (e.g., balloon, stent, plus guidewire and optional wire bundling function (described below)). An example is a wedge designed into a groove in an axial or coaxial guide rail such that when the slit interacts with the wedge, it expands wider so that it can slide onto the axis of the interventional device (e.g., balloon, stent, plus guidewire and optional wire bundling function (described below)). Similarly, the internal support feature can have an outer diameter shaft or rod, sized similar to or larger than the inner diameter of the slit support catheter lumen to facilitate slit opening. It may also be necessary to make the shaft or rod tapered so that it can be easily loaded and then begin to expand the slit. For example, as... Figure 40 The loading tool shown includes a loading rod 4000 having a proximal end 4006 and a distal end 4008. The proximal end 4006 has a smaller cross-sectional diameter than the distal end 4008. As the support catheter 4002 is advanced distally along the rod 4000, the longitudinal slit 4010 extends until it intersects with the interventional device 4004. The tip of the wedge may begin very small (similar to the width of the slit feature) and the maximum portion of the wedge may be equal to or greater than the diameter of the interventional device (optionally including a guidewire and optional wire bundle features (described below)).

[0284] In some implementations, because the loading tool is designed to allow single-operator use, features that free the hands during loading and provide stability may be beneficial. For example, the loading tool of this disclosure may have a flat base for stability. Some block styles are designed to lie flat on a table and have sufficient length, width, and thickness to ensure stability, for example, such as... Figure 34 , 35 Like in number 39.

[0285] In some embodiments, the tool of this disclosure may incorporate a handle or other gripping feature so that a user can stabilize the tool with one hand while using the other to advance the support conduit. This is particularly useful for designs that rely on internal tracks to track slit tubular components. For such designs, it may be useful to have the component protrude from the area where the slit opens so that the tool can be gripped. Figure 41 An example is provided in which the loading tool 4100 includes a handle 4102 projecting from the side of the loading rod 4104. The handle 4102 may be substantially flat or wedge-shaped, or any other desired shape, and may pass through a longitudinal slit 4106 defined by the tubular member 4108 supporting the conduit when the tubular member 4108 is inserted onto the rod 4104, provided that the slit 4106 and the handle 4102 are in the same plane.

[0286] The loading tool can also be configured to be mounted on the user's finger using a ring-shaped device attached to the tool. For example, Figure 42 The loading tool 4200 is shown, which includes an elongated rod 4202 and a ring feature 4204 protruding from it.

[0287] As previously mentioned, there are cases where an expandable slit support catheter is loaded onto the balloon shaft and wire. Interventional procedures may also involve the simultaneous use of two or more rapid exchange devices. For these applications, a separate temporary slit tube can be bundled together with the balloon shaft and wire, allowing the slit support catheter to be loaded onto the bundle before removal and, optionally, disposal of the temporary tube, for example, as... Figure 43 As shown, it displays a temporary binding sleeve 4300 including a longitudinal slit 4302. The binding sleeve 4300 can be loaded onto the intervention device 4304 and the guide wire 4306, and may further include a handle 4308 for easy removal.

[0288] Optionally, the binding device can have a clamshell design, for example, such as Figure 44 and 45 As shown. Figure 44The binding device 4400 includes a first cover 4402, a second cover 4404, and an interface 4406 therebetween. When clamped together or otherwise closed, the first portion 4402 and the second portion 4404 form an internal delivery tube 4408 and a cross-loading tube 4410 for receiving interventional devices and supporting catheters, respectively.

[0289] Figure 45 The binding device 4500 shown has a "clamshell" configuration characterized by a first cover 4502 and a second cover 4504 connected at a longitudinal hinge 4506. The binding device 4500 also includes a locking mechanism consisting of a lip 4508 configured to engage corresponding overhang features 4510 when the first portion 4502 and the second portion 4504 are folded together via the hinge 4506. The specific locking mechanism can vary and may include, for example, a snap-fit, clamping, or key mechanism.

[0290] like Figure 45 As further shown, the bundling device 4500 may include an internal inclined surface 4512, which is configured to expand the longitudinal slit supporting the catheter as the catheter approaches the interventional device. Viewed from the outside of the device, the inclined feature 4512 may resemble a valley of variable width extending into the interior of the device 4500. The configuration of the bundling device 4500 facilitates removal of the device from the spool and, from a manufacturing perspective, makes it easier to manufacture, for example, via injection molding. Optional caps or clamshell caps may also be used to help ensure the device remains within the slot.

[0291] The bundling device can be a separate tool (completely separate from the main loading tool) or an integrated part of the loading tool, for example, such as Figure 46 As shown, the loading tool 4600 may include an elongated shaft or rod 4602 that defines a binding tube 4604 at its distal end. The binding tube 4604 is configured to receive and hold various interventional devices (e.g., guidewires 4608 and treatment devices 4610) together. The binding device may be loaded onto the wire and shaft of the interventional device and may be removable. Thus, the binding tube 4604 may include a slit 4612 traveling parallel to one (or more) interventional devices, which may be clamped onto one (or more) interventional devices and subsequently removed in a similar manner. Loading and unloading the slit binding tube may be performed in a manner similar to the loading / unloading process used for loading / unloading the slit support catheter described herein, but on a much smaller scale. The inner diameter of the binding tube may be approximately 0.020 inches to 0.070 inches. The outer diameter is approximately 0.030 inches to 0.080 inches. The length of the portion of the slit bundle attached to the guidewire and treatment device is approximately a minimum of about 0.050 cm to approximately a maximum of about 35 cm, with a preferred length of approximately 0.5 cm to 10 cm.

[0292] In some implementations, features may be present to temporarily clamp the loading tool onto the treatment device shaft (and guidewire shaft or bundle). This may include clips, magnets, or juxtaposed features that result in temporarily locking the loading tool to the shaft, some examples of which are shown. Figure 47 The loading tool 4700 comprises a clamshell-type loading rod 4702, which is composed of a first portion 4704 and a second portion 4706, with an interface 4708 therebetween. A bundling tube 4710 is coupled to or integrally formed with the loading rod 4702. The bundling tube 4710 may also have a clamshell configuration, characterized by a first portion 4712 and a second portion 4714, with a gap or interface 4716 therebetween. A locking mechanism 4718 is configured to lock the first and second portions of the rod and the bundling tube together. Non-limiting examples of the locking mechanism 4718 may include a magnetic mechanism, a spring clip, a mechanical lock, or a combination thereof.

[0293] In some implementations, the loading tool may comprise a single tube with a slit and including a hole and an optional handle (e.g., a single tubular loading tool). Figure 48 The loading tool 4800 shown includes, for example, an angled tube 4802 consisting of a proximal loading tube 4804 and a slit tube 4806 defining a longitudinal slit 4808. The slit tube 4806 can be configured to clamp onto an interventional device inserted through a through-hole 4810 defined by the slit tube 4806. The length of the loading tube 4804 may be greater than that of the slit tube 4806 to allow gripping as the loading tube 4804 extends out of the slit tube 4806. The loading tube 4804 may also include a longitudinal slit 4812. Additionally or alternatively, an optional handle 4814 may be included for gripping. The handle 4812 is shown near the proximal end of the loading tube 4804, but in an additional embodiment, it may be positioned on the slit tube 4806.

[0294] In some embodiments, the slots sized to receive the interventional device and the support catheter may each include countersunk holes configured to prevent easy removal of the device from the slot. An example of such a device 4900 is shown in... Figure 49 As shown in the figure. The device 4900 includes a block-shaped main body member 4902 defining a bifurcated groove 4904, which is composed of a delivery groove 4906 and a loading groove 4908 (both of which can be countersunk).

[0295] In additional or alternative embodiments, one or more of the aforementioned accessory devices may be supplemented or replaced by a disposable loading device, for example, including a clamping component. According to this embodiment, the user can use the clamping component to clamp the support catheter onto the in-place interventional device before removal.

[0296] The disclosed support catheters can be used to perform a variety of medical procedures, including minimally invasive cardiac interventions, many of which involve the use of guidewires and guiding catheters. Guidewires may include elongated, small-diameter components designed to be guided within a blood vessel to reach a target lesion site or vascular segment. Guidewires can be configured in various ways, for example, including solid steel or nickel-titanium alloy core wires and / or solid core wires wrapped in smaller wire coils or braids. Guiding catheters or sheaths may include elongated tubular components that define a main lumen along their length. Guiding catheters may be formed of, for example, polyurethane and may be shaped along their distal portion for easy advancement to the coronary orifice (or other target areas within the patient). Any appropriately sized guiding catheter, such as a 6F, 7F, or 8F guiding catheter, can be inserted into the femoral or radial artery and advanced through the aorta to a location adjacent to the coronary orifice.

[0297] The following describes a non-limiting example of an interventional medical procedure related to pacemaker lead delivery that can be performed using the devices disclosed herein. Optimal cardiac pacing increasingly requires precise positioning of the pacemaker lead within the right ventricular chamber and / or branches of the coronary venous system. Pacemaker leads are typically delivered via conventional sheaths or pre-shaped guide sheaths (placed via the cephalic or subclavian veins). These sheaths are typically designed to be cut or slit and stripped once the lead is in place. The electrical connections of a typical pacemaker lead are often significantly larger than the axis of various existing guide extension catheters. The expandable slit support catheter of this disclosure, with its distal end positioned near the desired lead fixation point, can help optimize pacemaker lead positioning and fixation. The disclosed support catheter can be particularly advantageous when the pacemaker is positioned into the left ventricle through the patient-specific, anatomically variable coronary sinus.

[0298] In some embodiments, the method for delivering the pacemaker lead of this disclosure may involve introducing a guiding catheter or sheath 5000 into a blood vessel 5002 and advancing its distal end toward a target region 5003, such as Figure 50A As shown. For illustration, vessel 5002 may include the aortic arch and target region 5003 may include the cardiac chambers.

[0299] The guide sheath 5000, as a slender tubular component defining the lumen, can have an internal capacity of 8F, 7F, or 6F, which is commonly used in interventional cardiology procedures. An expandable slit support catheter 5004, with or without a distal pre-defined shape and a full-length longitudinal slit, can be positioned within and extend through the conventional or pre-shaped guide sheath 5000 until the distal end of the support catheter 5004 is located at or near the target area 5003, such as... Figure 50B As shown. At least one guidewire 5006 with a shaped distal end can be advanced through a sheath 5000 and a support catheter 5004, as shown. Figure 50CAs shown. Alternatively, the guidewire 5006 can be preloaded into the support catheter 5004 outside the patient's body and both devices can be introduced together.

[0300] A smaller diameter catheter or "microcatheter" (straight or curved) 5008 can be loaded onto the guidewire 5006 and manipulated to a desired location within the target area 5003. An expandable fissure support catheter 5004 can be advanced on the guidewire 5006 and loaded onto the smaller diameter catheter 5008 near the desired location, such as... Figure 50D As shown. Alternatively, a smaller diameter catheter 5008 can be loaded onto the guidewire 5006 and support catheter 5004 outside the patient's body, and the device can be introduced together.

[0301] Once the target location is reached, the guidewire 5006 and the smaller diameter catheter 5008 can be withdrawn and removed, as... Figure 50E As shown. The pacemaker lead 5012 can then be advanced via the guide sheath 5000 and the expandable slit support catheter 5004 to the desired target location 5010 within the target region 5003, as... Figure 50F As shown. Further manipulation of the expandable slit support catheter 5004 can facilitate final lead positioning and lead fixation. Once the pacemaker lead 5012 is secured in place, the expandable slit support catheter 5004 can be withdrawn and removed, for example, by the stripping method described above, as... Figure 50G As shown. The pacemaker lead 5012 can be kept at the target position 5010 to complete the interventional procedure.

[0302] In some embodiments, the methods of this disclosure may involve PCI procedures for bifurcation lesions. For some bifurcation PCI procedures, it is necessary to simultaneously inflate two treatment structures (e.g., balloons) within the coronary artery (or other vessels in non-coronary procedures) to address vascular constriction at the bifurcation caused by the lesion, which can affect the aorta and adjacent collateral branches. In some examples, the treatment structure may comprise two angioplasty balloons, two stent delivery balloons, or one angioplasty balloon paired with a stent delivery balloon. To treat some lesions using at least two treatment balloons, a support catheter may be required to deliver the first angioplasty or stent delivery balloon to the lesion site. Compared to a guiding catheter, a support catheter can reduce the cross-sectional lumen area available for the delivery and inflation of two treatment balloons. For example, two angioplasty or stent delivery balloons may not be possible to advance through a current tubular (non-slit) 5F-in-6F guiding support catheter. Due to the space constraints associated with using a slitless support catheter, once the first angioplasty or stent delivery balloon has been successfully delivered to the lesion by the support catheter, the support catheter must be completely removed from the guiding catheter before the second angioplasty or stent delivery balloon can be advanced through the guiding catheter. When the first angioplasty or stent delivery balloon is positioned at the lesion, only a small segment of the proximal balloon shaft may remain outside the guiding catheter. When the slitless support catheter is withdrawn and the first angioplasty or stent delivery balloon is positioned at the lesion, the proximal balloon shaft length may be insufficient to completely withdraw the support catheter from the guiding catheter. The only method to remove the slitless support catheter (without first withdrawing the angioplasty or stent delivery balloon) and allow advancement of the second angioplasty or stent delivery balloon may involve cutting the support catheter off the proximal balloon shaft.

[0303] The support catheter of this disclosure, in the form of a guide extension catheter with a full-length longitudinal slit, addresses the aforementioned problems by allowing easy, peel-off removal of the support catheter between the delivery of a first and second angioplasty or stent delivery balloon. For example, in some embodiments, the method of this disclosure may include introducing the guide catheter 5100 through an introducer or access sheath 5102, and advancing the guide catheter 5100 through the vessel 5104 toward the vascular bifurcation 5106 containing the lesion, such as... Figure 51A As shown.

[0304] The first guidewire 5108 can be introduced through the access sheath 5102, extended through the guide catheter 5100 to the vascular bifurcation 5106, and extended distally within the bifurcation aorta 5110, such as... Figure 51B As shown.

[0305] The second guidewire 5112 can be introduced into the guiding catheter 5100 and extended distally within the collateral artery 5114 of the bifurcation 5106, such as Figure 51CAs shown. Alternatively, the first guidewire 5108 may be inserted before, together with, or subsequently into the guiding catheter 5100 (in which the second guidewire 5112 may optionally be partially in the guiding catheter 5100).

[0306] The first balloon or stent delivery catheter 5116 (which may not be configured for easy advancement to the target site) can then be extended on the first guidewire 5108, as... Figure 51D As shown.

[0307] An expandable slit support catheter 5118 can be distally introduced and inserted into artery 5104 over both the first guidewire 5108, the second guidewire 5112, and the first balloon or stent delivery catheter 5116, until the distal end of the support catheter 5118 approaches the bifurcation 5106, such as... Figure 51E As shown.

[0308] The second balloon or stent delivery catheter can be introduced onto one of the guidewires (in this example, the first guidewire 5108) and extended distally to the bifurcation lesion of the aorta 5110, where it... Figure 51F The image shows the balloon ready for inflation or stent deployment. If simultaneous inflatation of two balloons, two stent delivery catheters, or one balloon and one stent delivery catheter is required, the second balloon or stent delivery catheter cannot be advanced in situ with the guiding extension catheter 5118 due to guiding extension inner diameter limitations. Advantageously, the guiding extension catheter 5118 can be withdrawn from the guiding catheter 5100 and completely removed via a slit from the proximal catheter shaft and first guidewire 5108 of the first balloon or stent delivery catheter 5116, as shown. Figure 51G As shown. The second balloon or stent delivery catheter 5120 can be advanced over the second guidewire 5112 and extended distally to the bifurcation lesion, as... Figure 51H As shown. Figure 51I The balloon is inflated simultaneously as shown. The first balloon or stent delivery catheter 5116 and the second balloon or stent delivery catheter 5120 can then be withdrawn.

[0309] The methods disclosed herein may further relate to PCI or peripheral interventions for treating one or more lesions. In some embodiments, the methods of this disclosure can provide treatment of the lesion without the need for a support catheter prior to the start of the procedure. This method may involve first introducing a guiding catheter 5200 through an access sheath 5202 and into a blood vessel 5204, such as... Figure 52A As shown. Guidewire 5206 can be placed and extended close to or beyond the target lesion 5208, such as... Figure 51B As shown. The treatment device 5210 can be inserted onto the guidewire 5206 and attempt to perform treatment, as... Figure 52A As shown.

[0310] An expandable slit support catheter 5212, having a full-length longitudinal slit 5214 and with or without a distal pre-defined shape, can be loaded onto a treatment catheter shaft 5216 that extends proximally toward the guide catheter 5200 or sheath 5202, such as Figure 52B As shown, it is not necessary to remove the treatment device 5210 first. The loading of the expandable support catheter 5212 can be performed by pushing open the slit 5214 and loading the entire tubular member 5218 of the support catheter onto the treatment catheter shaft 5216 via the slit. If the treatment device is a quick-change device, the expandable slit support catheter may need to be loaded onto both the treatment device and the guidewire. A loading tool can be used during this process.

[0311] The support catheter 5212 extends to the target lesion 5208, such that the proximal end 5220 of the tubular member 5218 remains within the guiding catheter 5200. The distal end 5222 of the tubular member 5218 can be positioned near or across the lesion 5208, for example, on the proximal side of the lesion, and the distal end 5224 of the treatment device 5210 is pushed across the lesion 5208, as... Figure 52C As shown. If the distal end 5222 of the tubular member 5218 is advanced through and across the lesion 5208, it is partially retracted, while the treatment device 5210 remains across the lesion. Then as... Figure 52D Treatment can be performed, for example, by expanding a balloon (with an optional stent) at the distal end of the interventional device. The expandable slit support catheter 5212 can be retracted such that the slit tubular member 5218 extends partially or completely beyond the proximal end of the guiding catheter 5200, or the sheath and support catheter can be detached or removed from the treatment catheter shaft 5216 and guidewire 5206, as described above. Figure 52E As shown. Treatment device 5210 can be reused (at the same lesion or another lesion) or removed. At the end of the procedure, guidewire 5206, guiding catheter 5200, and access sheath 5202 are removed (or the guiding sheath is removed).

[0312] In other embodiments, the method of this disclosure can provide treatment of the lesion when a support catheter is intended to be used, and may include first introducing an access sheath / guide catheter or guide sheath, such as Figure 51A As shown. Figure 51B As shown, the guidewire is placed and extended close to or beyond the lesion.

[0313] The support catheter described herein provides flexibility to interventional medical procedures in a way that improves surgical efficiency and speed, while also reducing the complexity often associated with procedures requiring guidance through tortuous portions of a patient's vascular system. Typically, for example, after a guidewire has been extended across a vascular lesion, the exposed support catheter can be deployed during a procedure involving the insertion of a treatment device via a guide catheter. The user performing the procedure can then recognize the need for backup support. Instead of removing the treatment device from the patient to make room for the support catheter, as was previously done, the exposed support catheter can be inserted onto the axis of the treatment device, advanced through the guide catheter, and optionally, fully or partially, onto the treatment device. Thus, the support catheter can quickly provide sufficient backup support to allow the treatment device to be advanced distally to locations inaccessible before the insertion of the support catheter.

[0314] In some examples, a support catheter can be loaded backward onto the interventional device during the medical procedure. Figure 53A The rearward loading of the support catheter 5300 is depicted. As shown, the support catheter 5300 includes a tubular member 5302 that defines a full-length longitudinal slit 5304, with or without a distal pre-defined shape. The support catheter 5300 can be rearwardly loaded on the distal end 5306 of the treatment catheter 5308, after which both devices can be introduced together into the target lesion.

[0315] Alternatively, the support catheter 5300 can be introduced into the guiding catheter 5310 on the guidewire 5312, and then the treatment device 5308 can be loaded and inserted through the support catheter 5300 and the guiding catheter 5310, as shown. Figure 53B As in the example. The interventional device 5308, with a supporting catheter 5300, can extend to the target lesion, such that the proximal end 5314 of the tubular member 5302 is held in the distal end 5316 of the guiding catheter 5310 near the lesion, as... Figure 52C As shown. Then perform the treatment, for example, as Figure 52D As shown. The support catheter 5300 can then be withdrawn, such that the slit tubular member 5302 extends partially or completely beyond the proximal end 5318 of the guiding catheter or sheath, and the support catheter is detached or removed from the treatment axis and guidewire, for example, as... Figure 52E As shown. The treatment device can be reused or removed. At the end of the procedure, the guidewire, guiding catheter, and access sheath are removed (or the guiding sheath is removed).

[0316] Example

[0317] Although this disclosure has been described with reference to preferred embodiments, those skilled in the art will recognize that changes in form and detail may be made without departing from the spirit and scope of this disclosure. Therefore, the foregoing detailed description is intended to be illustrative and not limiting. Unless expressly stated to the contrary, the above embodiments (or one or more features or components thereof) can be used in different combinations of each other. Other embodiments may be used, for example, by those skilled in the art upon consulting the foregoing detailed description. Furthermore, various features or components have been combined to simplify this disclosure. This should not be construed as meaning that any unclaimed disclosed feature is necessary for any claim. Rather, the subject matter of the invention may lie in fewer than all features of a particular disclosed embodiment. Therefore, the following embodiments are hereby incorporated into the detailed description, wherein each embodiment exists as its own independent embodiment.

[0318] In Embodiment 1, a device for use with a support catheter and at least one interventional device may comprise a body including an elongated delivery channel sized to receive and adapt to axial sliding of the interventional device. The device may also include an elongated loading structure sized to receive and adapt to axial sliding of a tubular member of the support catheter. The distal end of the elongated loading structure intersects the elongated delivery channel along its length.

[0319] In Embodiment 2, the apparatus of Embodiment 1 may optionally be configured such that the elongated loading structure includes a channel having wedge-shaped protrusions extending along its length. The cross-sectional dimensions of the wedge-shaped protrusions vary along their length.

[0320] In Embodiment 3, the apparatus of Embodiment 1 or Embodiment 2 may optionally be configured such that the distal portion of the elongated delivery channel gradually tapers to a width smaller than the proximal portion of the elongated delivery channel.

[0321] In Embodiment 4, a device for use with a support catheter and at least one interventional device may include an elongated loading rod sized to insert into a tubular member of the support catheter. The elongated loading rod also has a distal end configured to be axially coupled to the interventional device. The distal end of the elongated loading rod has a larger dimension than the proximal end of the elongated loading rod.

[0322] In embodiment 5, the device of embodiment 4 may optionally be configured to further include a handle that protrudes from one side of the elongated loading rod and is configured for user engagement.

[0323] In embodiment 6, the apparatus of embodiment 4 or 5 may optionally be configured such that the distal end of the elongated loading rod defines a cylindrical portion configured to bundle one or more interventional devices together.

[0324] In embodiment 7, the apparatus of any one or any combination of embodiments 4-6 may optionally be configured to further include two longitudinal members defining an interface therebetween. The two longitudinal members may be configured to be separated along their length, thereby creating a longitudinal gap therebetween. The apparatus may also include a locking mechanism configured to reduce the width of the longitudinal gap by bringing the longitudinal members closer together along their length.

[0325] In Example 8, a method for delivering two elongated medical devices to a lesion at a vascular bifurcation in a patient involves: positioning a first guidewire and a second guidewire in a guiding catheter and extending the first and second guidewires to the vascular bifurcation. The method also involves: positioning the first elongated medical device on the first guidewire and inserting it into the guiding catheter, extending the first elongated medical device to the vascular bifurcation. The method further involves: positioning a support catheter, including a tubular member comprising a longitudinal slit, on the first and second guidewires and the first elongated medical device by pushing a portion of the elongated medical device into a lumen defined by a tubular member. The method further involves: advancing the first elongated medical device distally until a distal treatment structure of the first elongated medical device is positioned at the lesion.

[0326] In Example 9, a method for treating lesions in a blood vessel using an elongated medical device involves: positioning a first guidewire in a guiding catheter and extending the first guidewire distally beyond the lesion. The method further involves: positioning the first elongated medical device on the guidewire and into the guiding catheter, and extending the first elongated medical device distally until a distal treatment structure of the first elongated medical device is positioned proximal to the lesion. The method also involves: positioning a support catheter including a tubular member on the first guidewire and on the proximal or intermediate portion of the elongated medical device by pushing a proximal or intermediate portion of the elongated medical device into a lumen defined by a tubular member, the tubular member comprising a longitudinal slit.

[0327] In Example 10, the method of Example 9 may optionally be configured to further involve advancing a tubular member of a supporting catheter along an elongated medical device until the tubular member is positioned proximal to the lesion, close to the treatment structure, and advancing the treatment structure of the elongated medical device distally to or beyond the lesion.

[0328] In Example 11, the method of Example 10 may optionally be configured to further involve inflating a balloon of the treatment structure.

[0329] In Example 12, the method of Example 11 may optionally be configured to further involve removing the support catheter by retracting the tubular member proximally and peeling the tubular member from the proximal or middle portion of the elongated medical device via a longitudinal slit.

[0330] In Embodiment 13, a guide extension catheter for use with a guide catheter includes an elongated tubular member having an angled proximal port or coupled to the angled proximal port and defining a longitudinal slit and lumen, and having an outer diameter smaller than the lumen of the guide catheter. The guide extension catheter also includes a pusher member eccentrically coupled relative to the axis of the tubular member and extending proximally to the tubular member for slidably positioning the tubular member within and partially beyond the distal end of the guide catheter.

[0331] In Example 14, the guiding extension conduit of Example 13 may optionally be configured such that the outer radial diameter of the elongated tube member gradually tapers to a distal end, such that the outer diameter at the distal portion of the elongated tube member is smaller than the outer diameter at the proximal portion of the elongated tube member.

[0332] In Embodiment 15, the guiding extension catheter of Embodiment 14 may optionally be configured such that the distal portion of the elongated tube member includes a flexible tapered distal tip configured to fold proximally into the distal portion of the elongated tube member.

[0333] In Example 16, any one or any combination of the guiding extension catheters of Examples 13-15 may optionally be configured such that the width of the longitudinal slit varies along its length.

[0334] In Example 17, the guiding extension catheter of Example 16 may optionally be configured such that the longitudinal slit includes two or more incision portions, each incision portion having a wider width relative to the rest of the longitudinal slit.

[0335] In Example 18, the guide extension conduit of any one or any combination of Examples 13-17 may optionally be configured such that the push member includes a flat portion embedded in at least a portion of the elongated tube member.

[0336] In Example 19, the guiding extension catheter of any one or any combination of Examples 13-18 may optionally be configured such that the distal portion of the elongated tubular member is bent.

[0337] In Example 20, the guiding extension catheter of any one or any combination of Examples 13-19 may optionally be configured such that the elongated tube member includes at least one support-like metal frame having a first interdigital member at a first end and a second interdigital member at a second end, the first interdigital member being complementary to the second interdigital member.

[0338] Conclusion

[0339] The detailed description above includes reference 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 drawings illustrate, in a stylistic manner, specific embodiments in which the support conduit, loading components, and related methods can be implemented. These embodiments are also referred to herein as "examples".

[0340] This patent document uses certain terms throughout to refer to specific features or components. As those skilled in the art will understand, different people may refer to the same feature or component using different names. This patent document is not intended to distinguish between components or features with different names but identical functions.

[0341] For the following defined terms, certain limitations will apply unless otherwise specified elsewhere in this patent document. The terms “a,” “an,” and “the” are used to include one or more, independent of any other instances or uses of “at least one” or “one or more.” The term “or” is used to refer to a non-exclusive “or,” such that “A or B” includes “A but not B,” “B but not A,” and “A and B.” Whether explicitly stated or not, all numerical values ​​are assumed to be modified by the term “about.” The term “about” generally refers to a range of numbers that a person skilled in the art would consider equivalent to the stated value (e.g., having the same function or result). In many cases, the term “about” may include numerical values ​​rounded to the nearest significant figure. The numerical range expressed by the endpoints includes all numbers within and limiting the range and subranges (e.g., 1 to 4 includes 1, 1.5, 1.75, 2, 2.3, 2.6, 2.9, etc., and 1 to 1.5, 1 to 2, 1 to 3, 2 to 3.5, 2 to 4, 3 to 4, etc.). The terms “patient” and “subject” are intended to include mammals, for example, in human or veterinary applications. The terms “distal” and “proximal” are used to refer to a position or direction relative to the treating clinician. “Distal” and “towards distal” refer to a position away from or in a direction away from the treating clinician. “Proximal” and “towards proximal” refer to a position close to or towards the treating clinician.

[0342] The scope of this invention should be determined by reference to the appended claims and the full scope of their equivalents. In the appended claims, the terms “comprising” and “therein” are used as concise English equivalents of the corresponding terms “including” and “wherein”. Furthermore, in the following claims, the terms “comprising” and “including” are open-ended; that is, an apparatus, kit, or method that includes features or components in addition to those listed after such terms in the claims is still considered to fall within the scope of that claim. Moreover, in the appended claims, the terms “first,” “second,” and “third,” etc., are used merely as labels and are not intended to impose numerical requirements on their objects.

[0343] An abstract is provided to allow readers to quickly determine the nature of the technical disclosure. Its submission is based on the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Claims

1. A guiding extension catheter, the guiding extension catheter being configured for use with a guiding catheter, characterized in that: An elongated tubular member having a longitudinal slit, a lumen, and an outer diameter of the lumen smaller than that of the guiding conduit, the elongated tubular member further having an angled proximal port opposite to or coupled to the angled proximal port of the elongated tubular member. as well as A pushing member, which is eccentrically coupled relative to the axis of the elongated tubular member and extends proximal to the elongated tubular member, is used to slidably position the elongated tubular member within and partially beyond the distal end of the guiding conduit. The longitudinal slit comprises a straight portion and at least one inclined or curved portion relative to the axis of the elongated tubular member, the at least one inclined or curved portion being located at the distal end of the straight portion, and the straight portion extending from the angled proximal port to a point 0.25 cm to 3 cm from the farthest end of the distal port portion.

2. The guiding extension catheter according to claim 1, wherein the at least one inclined or curved portion spans a length of 0.25 cm to 3 cm, including the end value.

3. The guiding extension catheter according to any one of claims 1 or 2, wherein the longitudinal slit comprises a notched slit that extends less than 100% through the wall of the elongated tubular member, such that the inner surface of the elongated tubular member is completely intact.

4. The guiding extension conduit of claim 3, wherein the notched slit is configured to facilitate tearing of the elongated tubular member.

5. The guiding extension conduit according to any one of claims 1 or 2, wherein the width of the longitudinal slit varies along the length of the elongated tubular member.

6. The guiding extension catheter of claim 5, wherein the longitudinal slit includes at least one incision portion having a wider width relative to the non-incision portion of the longitudinal slit.

7. The guiding extension catheter of claim 1, wherein the distal portion of the elongated tubular member is curved.

8. The guiding extension catheter of claim 7, wherein the longitudinal slit is located on the inside of the bend of the distal portion of the elongated tubular member.

9. The guiding extension catheter of claim 1, wherein the elongated tubular member comprises at least one support-like metal frame having a first interdigital member at a first end and a second interdigital member at a second end, the first interdigital member being complementary to the second interdigital member.

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