Balloon guide catheter without preparation phase

Abstract

The present invention is entitled "Balloon Guide Catheter with No Preparation Phase". The present invention provides a system having a balloon guide catheter for mechanical thrombectomy that requires minimal preparation to inflate the balloon compared to most contemporary designs. The balloon guide catheter may have an elongated tubular member and a proximal Luer interface. The elongated tubular member of the catheter may have two internal lumens. The first internal hollow lumen may have a larger opening for aspiration and propulsion assist device, and the second inflation lumen may provide a fluid pathway to inflate the balloon. The proximal Luer interface may have a Luer lumen, an inflation port, and a core shaft hub. A removable core shaft may extend distally from the core shaft hub to occupy the entire length and volume of the inflation lumen of the tubular member. A protrusion of the core shaft may extend outside the Luer interface to facilitate removal of the core shaft from the catheter prior to inflating the balloon.

Description

Technical Field

[0001] The present invention generally relates to devices and methods for removing acute blockages from blood vessels during endovascular medical treatments. More specifically, the present invention relates to balloon guide catheters for occluding portions of target blood vessels during such procedures. Background Art

[0002] A catheter may be a hollow, flexible structure used for a variety of applications and procedures within a patient's blood vessels. In many cases, a catheter may be guided to a target area in a particular blood vessel and then serve as a guide for other conventional and more specialized devices to access the area through the lumen of the catheter. Such devices may include microcatheters, guidewires, clot retrieval devices, aspiration catheters, or any of a variety of other commercially available accessory components.

[0003] Balloon guide catheters can be used in standard arterial or ischemic stroke surgery to serve as conduits for diagnostic and therapeutic devices, while also providing flow arrest, flow control and / or flow reversal to help safely remove clots from the patient. This flow control provides distal vascular protection, which is important for minimizing the risk of embolic migration and other procedural complications, particularly in the small and fragile brain channels of stroke patients. In addition, the proximal flow control provided by these catheters has been shown to be associated with better angiography and clinical outcomes. These catheters can be used to reduce the operating time and effort during the repassing process of intra-arterial mechanical thrombectomy. For example, they can limit the number of clot removal attempts required during ischemic stroke, while also reducing the incidence of distal embolism.

[0004] Balloon guide catheters must be flexible enough, while also having axial stiffness to smoothly deliver to the target site (usually the internal carotid artery and into the cerebral vasculature of ischemic stroke patients) through the tortuous vasculature. These devices must also be designed to be as non-invasive as possible while still delivering a high level of performance. Once access to the target is obtained and the balloon is deployed, the guide catheter must be quite stable to remain stable in this position while advancing, manipulating and withdrawing other devices through the lumen. The lumen itself must have a diameter large enough for these devices while also guiding the more effective suction required to remove blood and thrombotic material during surgery. However, the lumen size must be balanced by the need for an outer diameter as small as possible to minimize the size of the entrance hole that must be closed once the catheter is removed from the patient.

[0005] Although current designs must balance these tradeoffs, one of the most significant challenges and a barrier to wider adoption of these catheters is the process of preparing the catheter for use. Currently, before a balloon guide catheter is introduced into a blood vessel, a physician must flush the balloon and purge the system of air before any expansion media can be introduced. The current practice of removing air from the expansion lumen of existing catheters is laboriously long and frustrating, and can result in a great deal of waste. In addition, it may be difficult to tell the difference between a "significantly cleared" and a "completely cleared" system. However, failure to complete the clearing process can lead to complications such as cavitation, uneven expansion, and the release of trapped bubbles in the event of a balloon rupture during surgery. These events are likely to result in neurological deficits or other complications.

[0006] At present, the typical steps of clearing most balloon-guided catheter systems involve first connecting a stopcock to the proximal port connector of the catheter. A syringe is partially filled with contrast agent or other liquid and connected to the stopcock. Then the syringe plunger is actuated and maintained to aspirate the expansion lumen and balloon of the catheter. During this process, trapped air in the form of bubbles is sucked into the liquid of the syringe. The evacuated expansion lumen is enabled to be filled with contrast agent in the syringe by releasing the plunger. The process is repeated until bubbles are no longer observed during aspiration. Then, a separate syringe can be attached to the stopcock and used to inject contrast agent, thereby inflating the balloon. The balloon can then be checked for leaks or other defects. The balloon can then be deflated using a syringe so that it can be inserted into the vascular system. In some cases, bubbles remain until the balloon-guided catheter must be discarded and a new catheter is purchased and prepared. This harsh process requires caution and may frustrate the user, as well as adding considerable time to the overall duration of thrombectomy. The result may be a reluctance to adopt and use these devices during operations, where the benefits of these devices may improve the patient's recovery outcomes.

[0007] In order to limit the lasting damage, especially in ischemic stroke patients, there is a constant need to shorten the groin puncture to reperfusion time. The present design aims to provide an improved balloon guide catheter which addresses the drawbacks and gives the user greater flexibility during the procedure. Summary of the invention

[0008] The purpose of the present design is to provide systems, devices and methods that meet the above needs.As presented in the current design, having a balloon guide catheter that does not require the physician to perform tedious preparation steps before use can greatly reduce procedure time and thus lead to better clinical outcomes.

[0009] In mechanical thrombectomy, the current design facilitates preparation of the balloon guide catheter prior to balloon inflation. The design achieves this by integrating a removable mandrel into the catheter that is used to occupy the nominal volume of the inflation lumen prior to balloon inflation. By blocking the lumen, the mandrel removes trapped gas present within the system that would otherwise need to be evacuated prior to the medical procedure. When the physician is ready to inflate the balloon, the mandrel can be withdrawn from the system, thereby evacuating the inflation lumen. In the absence of trapped gas, the balloon can then be inflated using conventionally known techniques.

[0010] Various exemplary devices and methods are disclosed herein for minimizing the preparation required for balloon inflation of a balloon guide catheter. In addition, the disclosed devices address other shortcomings in the art, such as lumen kink protection and maximizing clot retrieval effectiveness.

[0011] The system may generally include a balloon guide catheter with a tubular core having an internal hollow catheter lumen. An elongated tubular member may be arranged around the core, but not concentric with the core. The elongated tubular member may have a distal end proximal to a distal end of the distal end of the core, and an independent expansion sleeve defining an expansion lumen independent of the internal hollow lumen. The internal hollow lumen may extend between the proximal end and the distal end of the core. The size of the internal hollow lumen may be set to maximize the clot removal capability, and may be a catheter for any of a microcatheter, a guidewire, a clot removal device, a suction catheter, or a variety of other commercially available auxiliary devices. The expansion lumen may extend from the expansion port at the proximal end to the balloon interior at the distal end of the elongated tubular member along most of the length of the core. The balloon may be attached to the distal portion of the tubular core, and may also be attached near the distal end of the elongated tubular member.

[0012] Near the proximal end of the catheter may be a Luer interface having a proximal end, a distal end integral with the elongated tubular member, and an internal Luer lumen. The Luer interface may also have an inflation inlet that provides a passageway for fluidly connecting the Luer lumen to the inflation lumen of the elongated tubular member. The Luer interface may have an inflation port and a mandrel hub, both of which may communicate with the internal Luer lumen.

[0013] The mandrel hub of the Luer interface may have a proximal port, wherein the mandrel is configured to pass through the proximal port and extend distally from the port along the full length of the expansion sleeve. The mandrel can be removably disposed within the mandrel hub of the Luer interface and the expansion sleeve. The mandrel may have a distal end and an opposite proximal end, which may include a mandrel protrusion. The mandrel protrusion may extend proximal to the proximal port and outside the Luer interface. The mandrel is sized so that it blocks the expansion lumen and occupies the entire internal volume of the expansion lumen. The mandrel may have an extended size to extend the distance between the mandrel hub and the balloon near the distal end of the balloon guide catheter. The proximal port of the mandrel hub may also have an air seal through which the mandrel passes. Whether the mandrel is present or not, the air seal prevents air from entering the Luer lumen and the expansion lumen.

[0014] The lumen of the expansion sleeve is in fluid communication with the balloon and can serve as a passage for expanding and contracting the balloon. The expansion sleeve can have any of a variety of shapes, but typically has a smaller cross-section than the internal hollow lumen. In one example, the expansion sleeve includes a generally crescent-shaped cross-section. The expansion sleeve can be formed of polyethylene (PE), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), or similar fluoropolymers.

[0015] The tortuosity may induce forces on the catheter body, and in extreme or abrupt angulations, one or more of the internal catheter lumen or the inflation lumen may become kinked. A kinked internal hollow lumen may constrain or completely prevent other devices from moving or operating therein. A kinked inflation lumen may inhibit flow to and from the balloon near the distal end of the catheter. These situations cause complications during treatment because a non-functional balloon guide catheter may need to be removed, with the physician then forced to perform surgery without stopping blood flow, or insert an additional tube through the inflation lumen to deflate the balloon. These situations also increase surgical time.

[0016] In order to reduce the possibility of kinking, the elongated tubular member may, for example, have a system of reinforcing wires or braids to support and fix the internal hollow lumen and the expansion lumen. The wire system may be embedded in the catheter and wound around the lumen to protect the expansion lumen and the internal hollow lumen along at least a portion of the length of the elongated tubular member. The wire can also enhance the torque capacity along the catheter length while protecting the expansion lumen from kinking. The wire system may be present on and / or around the expansion sleeve, and the sleeve may be radially joined to the inner core. The mesh system may be a braided wire mesh, or some similar structures that improve the strength of the catheter while reducing the overall stiffness of the catheter. In other wire configurations such as coiling, a stiffness gradient may be introduced along the various lengths of the catheter. If each wire has a circular, square or some other shaped profile, strength and flexibility may also be affected.

[0017] Another system for making a balloon guide catheter may include an elongated tubular member, a proximal Luer interface, and a seamless balloon.

[0018] The elongated tubular member may have a proximal end, a distal end, an outer surface, and two inner surfaces. The first inner surface may define an inner hollow lumen extending between the proximal end and the distal end of the elongated tubular member for delivering other catheters and / or devices to a target site. The second inner surface may define an expansion lumen extending along at least a portion of the length between the proximal end and the distal end of the elongated tubular member. The expansion lumen may be at least partially eccentric to the elongated tubular member and the inner hollow lumen. Similar to other examples, a reinforcing braid or mesh may be provided around the outer surface of the inner hollow lumen and the outer surface of the expansion lumen to provide kink protection. The expansion lumen may have a cross-section of an arc or crescent shape, and an area smaller than the inner hollow lumen, thereby allowing the expansion lumen to be eccentric and positioned closer to the outer edge of the elongated tubular member. This shape of the expansion lumen allows the larger inner hollow lumen to occupy most of the cross-sectional area of ​​the elongated tubular member, thereby improving the deliverability of other devices and improving suction efficiency.

[0019] The proximal Luer interface may include an internal lumen, an expansion port sized to receive fluid injection, a mandrel hub sized to receive a mandrel, and an air seal disposed within the mandrel hub to prevent air from entering the expansion lumen of the elongated tubular member. The mandrel can be removably disposed within the mandrel hub and extend into and through the expansion sleeve via an inlet proximal to the proximal end of the elongated tubular member. The inlet can provide a fluid passageway between the expansion lumen and the Luer lumen through the outer wall of the elongated tubular member.

[0020] The mandrel may be sized to completely block the entire length and volume of the inflation lumen so that there is no pre-existing gas within the inflation lumen, which may require repeated evacuation attempts to prepare for balloon inflation. The blocked distal portion of the mandrel may have an extended length to span the distance between the proximal port of the mandrel hub and the balloon at the distal end of the elongated tubular member. The proximal end of the mandrel may include a protrusion extending outside of the Luer interface and may be used by the user to grip the mandrel body and withdraw the mandrel body from the system when the physician is ready to inflate the balloon.

[0021] The seamless balloon can be fixed to the distal end of the elongated tubular member. The balloon can be joined to the elongated tubular member by a mechanical member (such as a ring tether), or attached by an adhesive or other means. By selecting a specific material for construction, such as a blend of silicone, elastomeric alloy, or similar materials, the balloon can be made soft and extremely conformable. When expanded, the balloon can provide a way to fix the catheter position in the blood vessel. In addition, the balloon can stop blood flow, thereby improving the efficiency of any suction guided by the internal lumen of the balloon guide catheter and / or other related catheters used in combination with the balloon guide catheter. Suction can be used to remove clots and prevent clot fragments from migrating distally, which potentially causes embolism of downstream distal blood vessels.

[0022] The larger interior hollow lumen of the elongated tubular member provides a more accessible conduit for delivering auxiliary products such as intermediate or aspiration catheters, microcatheters, and clot retrieval devices to the target site. The larger orifice of the lumen also simplifies the withdrawal of such devices with captured clots.

[0023] A method of utilizing a balloon guide catheter system that requires minimal preparation to inflate the balloon is also provided. The method may have some or all of the following steps and variations thereof, and the steps are listed in no particular order.

[0024] A system with a balloon guide catheter may be selected. The balloon guide catheter may have a proximal end, a distal end, an internal hollow lumen, an expansion sleeve defining an expansion lumen, a balloon, and a proximal Luer interface. The Luer interface may include an injection port, a core shaft hub, and a Luer lumen in fluid communication with the expansion lumen.

[0025] An air seal may be provided at the proximal end of the mandrel hub that prevents air from entering the Luer lumen. A removable mandrel may be provided to pass through the air seal in the mandrel hub and extend distally to occlude the entire volume of the inflation lumen.

[0026] Access to the patient's vasculature is obtained using conventionally known techniques, and the balloon guide catheter can be advanced into the vasculature to a position proximal to the target site. The Luer lumen can be filled with an expansion medium liquid through the expansion port of the Luer interface using a syringe or other expansion source. The liquid medium is typically a contrast medium solution, saline, or a mixture of the two. The proximal protrusion can then be pulled to withdraw the mandrel from the catheter to create a vacuum in the expansion lumen, thereby allowing the expansion medium in the Luer lumen to fill the expansion lumen along the length of the catheter. The balloon can be inflated by injecting additional expansion medium from the expansion source.

[0027] The method may also include the step of using other devices in conjunction with the balloon guide catheter. For example, mechanical thrombectomy can be performed using techniques known in the art. Any number of commercial products can be used for these surgeries, and therefore the method is not limited to those mentioned herein.

[0028] One step may involve advancing an intermediate catheter or a suction catheter through the inner lumen of a balloon guide catheter to a target site to aspirate the occlusive thrombus into the catheter head. Similarly, an optional step may utilize a microcatheter with a clot retrieval device that is advanced through the lumen of a balloon guide catheter. The microcatheter may be advanced onto the occlusive thrombus, and the clot retrieval device is deployed to capture and remove the thrombus under aspiration through the balloon guide catheter. In another example, the microcatheter with the clot retrieval device may have an access catheter or an intermediate catheter as an outer sheath. The intermediate catheter, the microcatheter, and the clot retrieval device may be advanced together through the lumen of a balloon guide catheter to reach the target site. The clot retrieval device may then capture and remove the thrombus.

[0029] In any of the foregoing examples, aspiration may be directed through any combination of a balloon guide catheter, an intermediate catheter, or other related aspiration catheters used during thrombus retrieval.

[0030] The balloon can be deflated by providing suction at the inflation port of the Luer to withdraw the inflation medium.After the procedure is completed, the system can be withdrawn from the vasculature.

[0031] Other aspects and features of the present disclosure will become apparent to those of ordinary skill in the art after reviewing the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other aspects of the present invention will be further discussed through the following description of the accompanying drawings, in which the same reference numerals indicate the same structural elements and features in the various figures. The accompanying drawings are not necessarily drawn to scale, but instead, emphasis is placed on illustrating the principles of the present invention. The accompanying drawings depict one or more specific implementations of the apparatus of the present invention by way of example only and not by way of limitation. It is expected that those skilled in the art will be able to conceive and combine elements from multiple drawings to better meet the needs of the user.

[0033] Figure 1 is an illustration of a system having a balloon guide catheter according to aspects of the present invention;

[0034] Figure 2 A close up isometric cross-sectional view of the distal tip of a balloon guide catheter showing the balloon inflated state according to aspects of the present invention;

[0035] Figure 3 Showing the various aspects of the present invention Figure 2A side cross-sectional view of the distal end of a balloon guide catheter;

[0036] Figure 4 According to various aspects of the present invention Figure 3 Cross-sectional view of the catheter tip;

[0037] Figure 5 is a diagram showing an internal lumen according to aspects of the present invention. Figure 3 Another cross-sectional view of the catheter end of FIG.

[0038] Figure 6 is a side view of a proximal Luer interface of a balloon guide catheter according to aspects of the present invention;

[0039] Figure 7 According to various aspects of the present invention, there is a core shaft Figure 6 A cross-sectional view of a Luer interface showing the internal fluid path;

[0040] Figure 8 According to various aspects of the present invention, there is a core shaft Figure 7 Detail of illustration of the area surrounding the expansion inlet;

[0041] Fig. 9 is downstream of the expansion inlet according to aspects of the present invention Figure 8 A cross-sectional view of the present invention, wherein the mandrel blocks the expansion lumen;

[0042] Fig.10 is the expansion inlet according to aspects of the present invention Figure 8 Another cross-sectional view of;

[0043] Figure 11A-11B is a view of a process of withdrawing a core shaft from a balloon guide catheter and filling a cavitation inflation lumen with an inflation medium according to various aspects of the present invention;

[0044] Fig.12 is an isometric view of a mandrel separate from a balloon guide catheter according to aspects of the present invention;

[0045] Fig.13 A balloon guide catheter for use with an intermediate catheter, a microcatheter, and a clot retrieval device to capture a target embolus in a blood vessel is shown according to aspects of the present invention;

[0046] Fig.14 Shown is a tip of a balloon guide catheter with a microcatheter and a clot retrieval device according to aspects of the present invention;

[0047] Figure 15-16 is a flow chart outlining one possible method of using a system according to aspects of the present invention. DETAILED DESCRIPTION

[0048] Specific examples of the present invention are now described in detail with reference to the accompanying drawings, wherein like reference numerals indicate functionally similar or identical elements. These examples address many of the drawbacks associated with preparing conventional balloon guide catheters for balloon expansion and remove steps and processes that can result in significant reductions in surgical time and waste.

[0049] Access to various blood vessels within the blood vessel (whether coronary, pulmonary or cerebral) involves well-known surgical procedures and the use of many conventional commercially available accessory products. These products, such as angiographic materials, rotary hemostatic valves and guidewires, are widely used in laboratories and medical procedures. When these products are used in conjunction with the systems and methods of the present invention in the following description, their function and exact construction are not described in detail.

[0050] See the attached figure, Figure 1 , a system 100 for preparing a balloon guide catheter 110 for use in surgery is shown. As shown, the catheter 110 of the system may have a proximal Luer interface 118, an internal hollow lumen 114, a removable core shaft 216, and a catheter tip 112 near the distal end 116 of the catheter. The internal hollow lumen can be used to deliver other catheters and auxiliary devices to the target site, while also providing a channel for aspiration and injection of contrast agents. The size of the lumen can vary based on the target site, or a standard guide catheter inner diameter of approximately 0.087" can be used. The Luer interface can be integrally formed with the distal tubular body of the catheter, or can be bonded to the distal tubular body of the catheter.

[0051] Figure 2 Show Figure 1 1 is an isometric cross-sectional view of a catheter tip 112 of a balloon guide catheter of FIG. The catheter body has an elongated tubular member 310 disposed around a tubular inner core 115. The inner core may be relatively thin-walled so that an inner hollow lumen 114 extending through the inner core may have a larger cross-sectional area for suction and passage of other devices. The inner hollow lumen may define a longitudinal axis 111 so that the elongated tubular member 310 is at least partially eccentric to the inner core 115 and the longitudinal axis 111. The smaller diameter of the inner core compared to the diameter of the elongated tubular member allows the balloon to be placed flush with the transverse profile of the catheter when the balloon is deflated. The flush placement provides a smoother delivery profile for the catheter. The balloon 113 may be attached to the elongated tubular member 310 at its proximal end and to the inner core 115 at its distal end.

[0052] The elongated tubular member 310 has an expansion lumen 117 extending parallel to the longitudinal axis 111, which may terminate at the distal end of the elongated tubular member within the lumen of the balloon 113. The elongated tubular member and the expansion lumen may extend along most of the length of the inner core 115. Prior to balloon inflation, the core shaft 216 occupies the expansion lumen, which extends from the interior of the proximal Luer interface 118 to the distal end of the elongated tubular member 310. The expansion lumen may be smaller than the internal hollow lumen because the volume of inflation medium required for balloon inflation is generally not very large. The inflation lumen may be crescent-shaped and may be approximately or about 0.2 mm. 2 This shape of the expansion lumen maximizes the interior space of the elongated tubular member 310 so that the interior hollow lumen 114 occupies most of the cross-sectional area. The larger inner diameter of the interior hollow lumen facilitates delivery of devices, contrast agents, and more efficient aspiration.

[0053] While elements are described and visualized in the drawings as tubular structures and are generally shown as substantially straight cylindrical structures, the terms "tubular" and "tube" as used herein should be understood broadly. They are not intended to be limited to structures that are perfect cylinders or that are completely circular in cross-section or have a uniform cross-section throughout their length.

[0054] Figure 3 1 shows a side view of the distal catheter tip 112 of the balloon guide catheter. The internal hollow lumen 114 can extend longitudinally with the expansion lumen 117 of the expansion sleeve 119 and terminate at the distal end 116 of the inner core 115. The expansion lumen can extend to the distal end over the entire length of the elongated tubular member 310 and evacuate in the balloon lumen 126. The expansion medium fluid (typically a 50 / 50 contrast agent mixture) can be injected into the proximal Luer interface to provide a fluid flow into the expansion lumen. The fluid can flow through the length of the expansion lumen and flow into the balloon cavity, as shown by the arrow.

[0055] The balloon 113 can assume an oval or conical shape when inflated, with a large, expanded radius of curvature for atraumatic interfacing with the vascular system wall. The balloon can be secured to the distal end of the elongated tubular member. The balloon can be joined to the outer surface 316 of the elongated tubular member 310 by a mechanical member, such as a ring tether or strap, or it can be crimped, welded, or attached by other means. In one example, the balloon is attached using a suitable adhesive means, such as epoxy or cyanoacrylate.

[0056] The body of the elongated tubular member 310 may be cut from a hypotube, or may be laminated, injection molded, or soft-melt welded to one or more outer sheaths in place. In one example, the elongated tubular member is cut from a hypotube having high column strength, thereby enabling good propulsion and torque characteristics, strain capacity for small bending radius, and high kink resistance. Common hypotube materials include nitinol and common stainless steel alloys such as 304 and 316. The elongated tubular member may have a uniform stiffness over its entire length, or a stiffness that varies along the length of the elongated tubular member. The stiffness distribution variation of the catheter may be produced by laser cutting features, such as machined circumferential slots or grooves and patterned ridges or depressions that are longitudinally or axially offset.

[0057] In other cases, the elongated tubular member 310 may be made of a polymer tube or of one or more multi-hardness polymer sheaths. During manufacture, one or more sheaths or sheath segments may be fused using heat. Changes introduced into the axial or radial arrangement of the sheath may customize the axial and lateral stiffness distribution from the proximal end to the distal end. For example, by configuring the sheaths axially in series, the overall stiffness of the catheter may be transformed from a harder proximal end to a very flexible distal end.

[0058] The surface of the polymer tube may also be formed with a series of ridges and depressions that provide enhanced torque, propulsion, and trackability features. Both the inner and outer surfaces of the catheter may be made of, or coated with, a lubricating, low-friction material such as PTFE. This ensures that when the catheter is guided through a blood vessel, there is a smooth, non-abrasive surface for contacting the inner vessel wall along the path to the target site.

[0059] To achieve the desired stiffness, other materials and / or additives having the desired stiffness properties may also be used in the construction of the elongated tubular member. The materials and / or additives may vary along the length of the elongated tubular member to form sections having different stiffnesses, each section having a different stiffness or hardness. Additional layers or additives may be provided to control the individual stiffness of each section of the elongated tubular member. However, it is desirable that the axial stiffness transition be relatively gradual, because otherwise the catheter may be biased to kink in areas where flexibility changes dramatically.

[0060] In another example, the elongated tubular member 310 may have a proximal end, a distal end, an outer surface 316, and two inner surfaces. The first inner surface may define an inner hollow lumen 114 for delivering an auxiliary device or for delivering aspiration or contrast media. The first inner surface may be at least partially eccentric to the elongated tubular member. The second inner surface may define an expansion lumen 117 extending therethrough, which may have a circular arc or crescent-shaped cross-section. In this way, the expansion lumen may be smaller than the inner hollow lumen and occupy a smaller interior volume of the elongated tubular member.

[0061] Figure 4 and Figure 5 for Figure 3 Cross-sectional view of the catheter tip. Figure 4 A cross-sectional view of the catheter tip is shown through the inflation balloon 113. The corresponding contours of the balloon lumen 126, the inflation lumen 117, and the inner hollow lumen 114 can be seen. The balloon can have a rounded contour when inflated as shown, or can take another shape as designed for a particular procedure.

[0062] The expansion lumen 117 can act as a conduit for the expansion medium that inflates and deflates the balloon 113. The expansion lumen can be connected to a port at the proximal end of the catheter, extend along most of the length of the elongated tubular member, and empty into the balloon lumen. The expansion lumen can have any number of shapes, including but not limited to a crescent shape of a specific arc radius size. The expansion lumen can be a sleeve of polytetrafluoroethylene (PTFE), polyethylene (PE), polyethylene terephthalate (PET), fluorinated ethylene propylene (FEP), etc.

[0063] The balloon can be constructed of any of a variety of materials, such as Chronoprene, polyurethane, nylon, PBx, or another thermoplastic elastomer. These materials make the balloon durable and thin. The balloon may or may not be air permeable, as the design of the catheter does not require air to diffuse out of the balloon during preparation. For atraumatic lubricity, the outer surface of the balloon can be coated with a hydrophilic coating, and the balloon can be shaped so that there is a minimal contact zone with the vessel wall when inflated.

[0064] Advancement through particularly tortuous vasculature may cause the catheter 110 and associated lumen to kink or curl. Kinking of the internal hollow lumen 114 may cause binding on a guidewire or other device. The kinked expansion lumen 117 may inhibit flow to and from the balloon of the balloon guide catheter, which may reduce the rate of expansion or contraction of the balloon or completely prevent expansion or contraction of the balloon. In some extreme cases, the kinked expansion lumen may cause the balloon to fail completely or lose the ability to inflate or contract the balloon. This may cause complications during treatment because the non-functional balloon guide catheter may need to be removed, the physician may need to perform surgery without blocking blood flow, or some other device may need to be inserted through the expansion lumen to deflate the balloon.

[0065] To prevent kinking, the catheter profile may include joining the outer surface of the expansion sleeve 119 to a reinforcing wire formation or braided mesh 318 on the outer surface of the inner core 115 along the length of the catheter, such as Figure 5. The reinforcing mesh may be wrapped within the polymer tube of the elongated tubular member 310 and may function similarly to rebar to prevent kinking of the catheter while maintaining consistent lateral flexibility for stable trackability. The reinforcing mesh may have a consistent structure and spacing along the axis of the catheter, or may vary in shape and density along various lengths. For example, changing the mesh profile may increase the flexibility of the distal end of the catheter while still minimizing the possibility of kinking of the expansion lumen. The strands may extend in a substantially parallel manner or in a cruciform configuration.

[0066] Other examples may change the braided mesh to a wire coil geometry to reduce the bending stiffness of the catheter 110 compared to a braid. The density of the coils or the materials used in their construction may be adjusted to change the axial stiffness profile of the catheter. Adding coils instead of braid reduces this "whip" orientation near sharp bends or loops in the blood vessel.

[0067] The elongated tubular member 310 may also have an outer surface 316 including one or more outer sheaths or liners that provide a reduced friction surface. One or more sheaths may be laminated, injection molded, or soft-melt welded to a suitable position. The outer surface 316 of the elongated tubular member and the surface of the inner hollow lumen 114 may be coated with a lubricating low-friction coating such as PTFE, high-density polyethylene, or similar fluoropolymers. The coating may be applied via spraying, plasma, or any other applicable method so that it is smooth and uniform. When the catheter is guided through the vascular system, the outer sheath may effectively provide a smooth surface for sliding along the inside of the blood vessel without injuring or scratching the blood vessel or generating excessive friction that would hinder the catheter from being delivered to the treatment site. Similarly, the coating or lining on the inner hollow lumen will be easy to advance and guide other devices through the lumen.

[0068] Figure 61 shows a Luer interface 118 near the proximal end 121 of the balloon guide catheter. The Luer interface can be a self-sealing connector with a typical connector for receiving an attachment. The Luer interface can be a rigid shell having a proximal end, a distal end, an expansion port 210, and a mandrel hub 214 constituting the proximal end 121 of the catheter. The shell of the Luer interface is configured to be hermetically sealed when in use. The proximal end can serve as an inlet for other devices used in endovascular surgery. As seen in the previous figures, the elongated tubular member 310 can be contained within the Luer interface toward the proximal side and can extend downstream from the distal end of the Luer interface. The expansion port 210 can branch radially away from the longitudinal main body portion of the Luer interface. The size of the port can be set to receive or transmit fluids, such as entering or leaving a syringe. The Luer interface can have a mandrel hub 214 as another rod deviating from the main body, and a removable mandrel 216 can be disposed within the catheter to leave the mandrel hub proximal to reach the outside of the Luer interface 118. Actuation of the mandrel is achieved by manipulating the mandrel tab 217 at the proximal end of the mandrel. The mandrel can be removed by tensioning the mandrel tab to slide the mandrel out of the mandrel hub.

[0069] Figure 6 The luer interface 118 shown in the and other figures is used to illustrate a single aspect of the present design. Of course, the present design can be applied to other luer interfaces of various shapes, sizes and practicalities as long as the mandrel is accommodated as described.

[0070] Figure 7 2 shows a view of the interior of the Luer interface 118 without the removable mandrel. The Luer interface can have an internal Luer lumen 212 that forms a hollow passageway of the inflation port 210. The elongated tubular member 310 can be combined with or integrally formed with the Luer interface housing. The elongated tubular member can start from a proximal end 314 in the housing and extend distally. Access to the inflation lumen can be provided via an inflation inlet 222 passage through the sidewall of the elongated tubular member 310 and near the proximal end of the elongated tubular member. The inflation inlet provides a fluid passage between the Luer lumen and the inflation lumen to allow the balloon to inflate and deflate via the Luer interface.

[0071] An air seal 218 may be disposed at the proximal end of the mandrel hub 214. The seal may be a compression gasket or other such methods known in the art. The proximal end of the seal may be flush with the outer surface of the mandrel hub, extend from the outer surface of the mandrel hub, or be recessed from the outer surface of the mandrel hub. The air seal provides the practicality of maintaining a pressure barrier and preventing air from entering the Luer interface even if the removable mandrel has been removed from the mandrel hub. Thus, when the mandrel has performed its function, the seal protects the internal catheter environment from contamination. The seal may also prevent air bubbles from being trapped during expansion or contraction of the balloon.

[0072] Figure 8It is shown in Figure 7 Detailed view of the interior of the Luer interface 118 of the embodiment of the present invention, including the outline of the core shaft 216. Prior to balloon inflation, at least a length of the core shaft 216 may extend through the air seal 218 of the proximal port 220 of the core shaft hub to exit the Luer interface and provide an external gripping surface for the user. Inside the Luer interface, the core shaft may pass through the core shaft hub 214 and enter the expansion sleeve 119 of the slender tubular member 310 via the expansion inlet 222 or proximal to the expansion inlet. The Luer lumen 212 may act as a small volume reservoir when the core shaft 216 is in place and prevent fluid from entering the expansion sleeve through the expansion inlet. The entry of the core shaft into the expansion sleeve may occur proximal to the expansion inlet or through the expansion inlet itself.

[0073] Figure 8 Also shown in the figure is a detailed view of the interface around the expansion inlet 222. The mandrel 216 can be a flexible elastomer or other material with a high elastic strain limit, so that it is flexible enough to bend into an arc - as shown in the figure from the radially offset mandrel hub 214 to the generally longitudinal expansion sleeve 119 of the slender tubular member 310. The expansion inlet can be shaped so that it is conducive to transitional bending. In one example, the longitudinal shape of the expansion inlet can be tapered so that when the mandrel is inserted from the mandrel hub and fed into the catheter, the distal end of the mandrel converges into the expansion inlet and the expansion lumen through the tapered portion. From the expansion inlet, the mandrel continues distally in this "off-axis" configuration, thereby blocking the entire internal volume of the expansion lumen. In this way, the mandrel prevents any gas or other medium from occupying the expansion lumen prior to the use of a balloon guide catheter and initial expansion of the balloon.

[0074] Fig. 9 The expansion inlet is shown distally and downstream of the Figure 8310 . The elongated tubular member may be integrally formed with the Luer interface, or the outer surface 316 of the elongated tubular member may be bonded or press-fitted to the inside of the Luer interface housing. The elongated tubular member may have at least two inner surfaces. The first inner surface may define an inner core 115 and an inner hollow lumen 114 extending through the inner core. The second inner surface may define an expansion sleeve 119, which details the periphery of the expansion lumen 117. As with the other examples, the cross-section of the expansion lumen may be smaller than the cross-section of the inner hollow lumen. The expansion lumen 117 occupied by the mandrel 216 prior to balloon expansion may be oriented radially upward or "12 o'clock" relative to the inner core 115 and the inner hollow lumen 114, or it may be in some other clock orientation. The reinforcing braid or mesh 318 may have interlocking strands and extend around the outer surface of the inner core and the expansion sleeve. The braid may be in a cross configuration, a helical orientation, or some other manner to reinforce and provide kink resistance to the catheter and lumen. The density of the reinforcing mesh may also be used to affect the rigidity properties of the catheter, allowing a more longitudinally rigid proximal portion and a more flexible distal portion.

[0075] Fig.10 Also shown is a portion of the expansion inlet 222 extending through the housing of the Luer 118 and the elongated tubular member 310. Figure 8 The mandrel 216 occupies a crescent-shaped cross-section of the expansion sleeve 119 prior to balloon inflation. Due to the shape of the inflation lumen 117, the inner core 115 and the associated inner hollow lumen 114 are not concentric with the elongated tubular member 310. The cross-section of the expansion sleeve is crescent-shaped in this example, but if another shape is used for the expansion sleeve, the mandrel area can also be customized for that geometry.

[0076] When the balloon guide catheter has been advanced through the vasculature to the target site of the occluded clot, the balloon can be inflated to block flow in the vessel and block fluid proximal to the catheter tip. In most examples, the seamless balloon is inflated within the patient's vessel using contrast medium, saline, another neutral fluid, or a combination of these. Typically, equal parts of contrast medium solution and saline are used. When the system is at the target site and the user is ready to inflate the balloon, a small amount of expansion medium 26 can first be injected into the trunk of the expansion port 210 via an expansion source or syringe 25 to pre-fill the Luer lumen 212, such as Fig.11A Prefilling the Luer lumen ensures that when the mandrel is removed from the catheter and access to the inflation lumen 117 through the inflation inlet 222 is opened, the evacuated space in the inflation lumen is filled with contrast media from the Luer lumen.

[0077] Fig. 11BThe process of removing the mandrel 216 when the operator is ready to inflate the balloon is shown. The mandrel can be withdrawn proximally from the mandrel hub 214 of the Luer interface 118, while the air seal 218 maintains an airtight seal inside the Luer interface. When the mandrel body has left the expansion inlet 222 hole through the wall thickness of the elongated tubular member 310, the volume of the contrast agent 26 in the lumen 212 of the expansion port 210 is sucked into the expansion lumen 117 by the adverse pressure gradient left by the removal of the mandrel. This eliminates the steps required to remove air, which would otherwise nominally occupy the expansion lumen. The internal hollow lumen 114 of the inner core 315 is undisturbed during this fluid transfer. The mandrel can be completely removed from the Luer interface, or the tail can be left at some internal position between the expansion inlet and the proximal port 220 of the mandrel hub. At this point, further injection of the expansion medium into the expansion port will inflate the balloon. The fluid volume and / or pressure remain constant to keep the balloon engaged with the vascular cavity, thereby preventing flow through the balloon. Once the procedure is complete, or to reposition the catheter, the balloon can be deflated by pulling the syringe's plunger to withdraw the medium.

[0078] Fig.12 216 is an isometric view of a mandrel 216 that is independent of the catheter system. The body of the mandrel may take the shape of a crescent of an expansion sleeve so that it occupies the entire volume of the expansion lumen before the balloon is expanded. Navigation to the target site of the operation may involve not only flexure, but also torsion and a small bending radius. Therefore, the mandrel may be made of a highly elastic flexible material so that it can adapt to the associated strains imparted by the path and the catheter body. The mandrel protrusion 217 may be integrally formed with the mandrel or formed independently of the mandrel. The protrusion may be any of a variety of shapes so that it can be easily clamped and has a feature that provides positive tactile feedback to the user. In one example, the protrusion may have a ridge or diamond plate pattern for enhanced clamping. The outer surface of the mandrel may be coated with a low friction lubricating coating so that it can slide more freely when it is withdrawn from the catheter in preparation for balloon expansion.

[0079] The balloon guide catheter of this design, which requires minimal preparation for balloon inflation, can also be used in conjunction with other mechanical thrombectomy devices. Fig.13, the balloon guide catheter 110 can be advanced through the target vessel 20 to a position proximal to the occluded clot 40. The balloon 113 can be inflated to block proximal flow in the vessel. An entry catheter, such as the intermediate catheter 35 or the suction catheter can be advanced through and beyond the distal end of the balloon guide catheter to reach the target. The microcatheter 70 containing the clot retrieval device 60 can be further advanced through the intermediate catheter and the balloon guide catheter, and deployed to capture the clot 40 while suctioning through one or more catheters. After capturing the clot, the clot retrieval device can be withdrawn into the intermediate catheter, which can compress the structure of the device and enhance the clamping force applied to the clot during retrieval. The clot retrieval device 60, the microcatheter 70, the intermediate catheter 35 and the clot 40 can then be withdrawn through the balloon guide catheter 110 and completely removed from the patient's body.

[0080] When the system is used in conjunction with other intermediate catheters or aspiration catheters, the system can use aspiration in conjunction with one or more flow restrictors or seals that can be selectively triggered to project aspiration to the distal lumen of the desired catheter. The seal can be a hydrogel, annular expandable balloon-type member, with a molded O-ring profile, or can have a frame with a membrane covering. For example, the system can be provided with an intermediate catheter 35 disposed within a balloon guide catheter 110, such as Fig.13 If suction is applied to the proximal lumen of the balloon guide catheter and a circumferential seal is triggered between the outer surface of the intermediate catheter and the inner surface of the balloon guide catheter, the entire force of the suction can be transferred to the distal end of the intermediate catheter. Similarly, if the seal is not triggered, the suction will be split between the intermediate catheter 35 and the balloon guide catheter 110.

[0081] The clot retrieval device 60 referred to in this specification may be any of a number of commercially available products, and many of these products share many common features. Some devices compress the clot when captured to obtain a firm grip, but this tends to make the clot tighter or "stickier", which can complicate retrieval. Other devices seek to expand between the clot and the vessel in a manner that minimizes compression while loosening the clot from the vessel wall. Typically, such devices may be made of nitinol or another shape memory material with sufficient elastic strain capacity so that the elastic limit is not exceeded when the device 60 is in a contracted delivery configuration within the microcatheter 70. This elastic strain capacity allows the device to be effectively "spring-loaded" within the microcatheter so that it can self-expand to engage the clot when deployed from the distal end of the microcatheter.

[0082] As is known in the art, placement of a balloon guide catheter during surgery can be aided by the addition of a radiopaque marker. Such markers may include radiopaque alloying elements such as palladium, platinum, gold, etc. For example, a radiopaque marker may be placed distal to the balloon at the distal end of the catheter. The marker may be placed on the inner core to mark the terminal end of the balloon during surgery.

[0083] As another example, the balloon guide catheter 110 can be maneuvered to the internal carotid artery, the balloon 113 can be inflated, and the microcatheter 70 and clot retrieval device 60 can be advanced through the interior hollow lumen 114 and deployed immediately from the distal end 116 of the balloon guide catheter tip 112. This standard procedure is as follows Fig.14 As shown. The balloon can be inflated using the process already described in this specification. The inflated balloon blocks blood proximal to the target site so as not to interfere with the capture of the clot, and suction can be applied through the balloon guide catheter to prevent fragments or debris from migrating distally from the target site. If additional retrieval attempts are required to clear the vessel, the microcatheter 70 and clot retrieval device 60 can be quickly delivered back to the target site.

[0084] Fig.15 and Fig.16 Flowcharts each include method steps for performing mechanical thrombectomy with such a system. The method steps can be implemented by any of the exemplary systems, devices, and / or apparatus described herein or by means known to one of ordinary skill in the art. The described method steps can be effectively performed without the laborious clearing steps associated with other balloon guide catheter systems.

[0085] See also Fig.15In the method 1500 outlined in , step 1510 describes the task of selecting a balloon guide catheter for mechanical thrombectomy. The balloon guide catheter may have a proximal end, a distal end, an internal hollow lumen, and a proximal Luer interface with a Luer lumen. In addition, the catheter may have an expansion sleeve and a balloon, the expansion sleeve defining an expansion lumen separated from the internal hollow lumen, the balloon being used for flow prevention and effective suction at the target site. In step 1520, an air seal may be disposed in the mandrel hub of the Luer interface to prevent air and other contaminants from entering the Luer lumen. The seal may be achieved by any of a variety of methods known in the art for hermetically sealing medical devices. In step 1530, a removable mandrel is disposed to pass through the air seal, the mandrel extending distally to occupy the entire volume of the expansion lumen, eliminating trapped gas present in the system before expansion. Step 1540 provides access to the patient's arterial blood vessels using conventional, well-known techniques. In step 1550, a balloon guide catheter is advanced into the blood vessel and through the blood vessel to a location proximal to the occluding clot using methods common in the art. In step 1560, the Luer lumen may be filled with a small amount of inflation medium through the inflation port of the Luer interface. This step may be accomplished by injecting a portion of the inflation medium from a filled syringe. Alternatively, this step may involve venting the Luer lumen with a gas permeable membrane.

[0086] See also Fig.16 In step 1610, the user may pull the proximal protrusion of the mandrel to withdraw the mandrel from the catheter and draw a vacuum in the inflation lumen. The inflation medium in the Luer lumen is thereby drawn into the inflation lumen. Then, in step 1620, the balloon may be inflated by injecting additional inflation medium through the inflation port of the Luer interface.

[0087] Once the balloon is fully deployed, as with large distal internal carotid artery (ICA) occlusions, occlusive clots can sometimes be removed by suction directly via the balloon guide catheter. However, in many cases, the next steps involve variations in mechanical thrombectomy that use other methods to remove clots. Such operations are well known in the art, and the steps herein are not intended to be an exhaustive list. In step 1630, the intermediate catheter can be advanced through the balloon guide catheter to the target location and used to aspirate the occlusive thrombus. The alternative in step 1640 involves advancing the microcatheter and clot retrieval device to the target location through the balloon guide catheter, and deploying the clot retrieval device to capture the occlusive thrombus, and with suction. In another example in step 1650, the intermediate catheter is advanced through the balloon guide catheter, and the microcatheter and clot retrieval device are advanced to the target location through the intermediate catheter. The microcatheter and clot retrieval device are advanced on the thrombus, and the clot retrieval device is deployed to capture the thrombus, and with suction through one or more catheters. In step 1660, flow reversal is achieved by directing aspiration through the balloon guide catheter as the thrombus is removed.

[0088] The present invention is not limited to the examples described, the construction and details of which may vary. The terms "distal" and "proximal" are used throughout the foregoing description and refer to positions and directions relative to the treating physician. Similarly, "distal" or "distalward" refers to a position away from the physician or in a direction away from the physician. Similarly, "proximal" or "proximal" refers to a position close to the physician or in a direction toward the physician.

[0089] In describing the examples, terminology is employed for the sake of clarity. It is intended that each term assumes its broadest meaning as understood by those skilled in the art, and includes all technical equivalents that operate in a similar manner to achieve similar purposes. It should also be understood that reference to one or more steps of a method does not exclude the presence of additional method steps or intermediate method steps between those explicitly identified steps. The steps of the method may be performed in an order different from that described herein without departing from the scope of the disclosed technology. Similarly, it should also be understood that reference to one or more components in a device or system does not exclude the presence of additional components or intermediate components between those explicitly identified components.

[0090] As discussed herein, a "patient" or "individual" can be a human or any animal. It should be understood that the animal can be of any suitable type, including but not limited to mammals, veterinary animals, livestock animals, or pet animals, etc. For example, the animal can be a laboratory animal (e.g., rats, dogs, pigs, monkeys, etc.) that is specifically selected to have certain characteristics similar to humans.

[0091] "Comprising" or "containing" or "including" means that at least the named compound, element, particle or method step is present in the composition or article or method, but does not exclude the presence of other compounds, materials, particles, method steps, even if other such compounds, materials, particles, method steps have the same function as those named.

[0092] It should also be noted that, as used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as "about" or "approximately" one particular value and / or "about" or "approximately" another particular value. When such a range is expressed, other exemplary embodiments include from the one particular value and / or to the other particular value.

[0093] As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or elements to achieve its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of ±20% of the value of the recited value, for example, "about 90%" may refer to a range of values ​​from 71% to 99%.

[0094] The descriptions contained herein are examples of embodiments of the present invention and are not intended to limit the scope of the present invention in any way. Although specific examples of the present invention have been described, various modifications may be made to the apparatus and method without departing from the scope and essence of the present invention. For example, although the examples described herein relate to specific components, the present invention includes other examples of realizing the functions using various combinations of components, realizing the functions using alternative materials, combining components of various examples, combining components of various examples with known components, etc. The present invention contemplates replacing the components shown herein with other well-known and commercially available products. For those of ordinary skill in the field to which the present invention relates, these modifications are generally obvious and are intended to fall within the scope of the following claims.

Claims

1. A system for preparing a balloon guide catheter, the system comprising: A catheter, the catheter comprising: a tubular core having an interior hollow lumen; and an elongated tubular member disposed about the inner core and comprising an expansion sleeve having an expansion lumen extending therethrough, the elongated tubular member and the expansion sleeve extending along a majority of the length of the tubular inner core; A proximal Luer interface, the proximal Luer interface comprising: a proximal end and a distal end; internal Luer lumen; an inflation port in fluid communication with the Luer lumen; and a mandrel hub having a proximal port, the mandrel hub being in fluid communication with the Luer lumen; a mandrel removably disposed within the mandrel hub and the expansion sleeve, the mandrel occupying the entire volume of the expansion lumen and further comprising a protrusion extending proximally from the proximal port of the mandrel hub exterior to the proximal Luer interface, the protrusion being configured to enable removal of the mandrel from the mandrel hub and the entire volume of the expansion lumen; and A balloon is in fluid communication with the inflation lumen of the inflation sleeve.

2. The system of claim 1 further comprising an inflation inlet in fluid communication with the Luer lumen and the inflation lumen.

3. The system of claim 1, wherein the inflation lumen is smaller than the inner hollow lumen.

4. The system of claim 1, wherein the expansion sleeve comprises a crescent-shaped cross-section.

5. The system of claim 2, wherein the mandrel is configured to be removed from the mandrel hub prior to inflation of the balloon to create a vacuum in the inflation lumen, and in, Inflation media from the Luer lumen fills the inflation lumen along the length of the catheter.

6. The system of claim 2, wherein the proximal port of the mandrel hub comprises an air seal that prevents air from entering the inflation lumen.

7. The system of claim 1, wherein the balloon is attached to a distal portion of the tubular core.

8. The system of claim 1, wherein the elongated tubular member is configured to be at least partially eccentric to the tubular core.

9. A system for preparing a balloon guide catheter, the system comprising: A catheter, the catheter comprising: An elongated tubular member, the elongated tubular member comprising: proximal end; distal end; External surface; and a first interior surface defining an interior hollow lumen extending therethrough, the interior hollow lumen being at least partially eccentric to the elongated tubular member; a second inner surface defining an inflation lumen extending therethrough; A proximal Luer interface, the proximal Luer interface comprising: internal lumen; an expansion port sized to receive an injection of a fluid; a mandrel hub having a proximal port sized to receive the mandrel; and an air seal disposed in the mandrel hub to prevent air from entering the inflation lumen of the elongated tubular member; a mandrel removably disposed within the mandrel hub and further comprising a protrusion extending proximally from the proximal port of the mandrel hub exterior to the proximal luer, the protrusion being configured to enable removal of the mandrel from the mandrel hub and the full volume of the inflation lumen; and A seamless balloon is in fluid communication with the inflation lumen.

10. The system of claim 9, wherein the seamless balloon is secured to the distal end of the elongated tubular member.

11. The system of claim 9, wherein the mandrel is shaped to occlude an entire cross-section of the inflation lumen.

12. The system of claim 9, wherein the inflation lumen is smaller than the inner hollow lumen.

13. The system of claim 9, wherein the inflation lumen comprises a crescent-shaped cross-section.

14. The system of claim 9, further comprising an inlet proximate a proximal end of the elongated tubular member, the inlet providing a fluid pathway between the inflation lumen and the interior lumen of the proximal Luer.

15. The system of claim 14, wherein the mandrel is sized to occupy the entire volume of the inflation lumen and the mandrel is configured to be removed from the mandrel hub prior to inflation of the balloon to create a vacuum in the inflation lumen, and in, Inflation medium from the interior lumen fills the inflation lumen along the length of the catheter.

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