Balloon guide catheter with positive venting of residual air

Abstract

The present invention provides a balloon guide catheter, which includes a catheter shaft, the catheter shaft having a main lumen defined in the catheter shaft and an expansion lumen axially defined in the catheter shaft, the main lumen extending axially through the catheter shaft to receive a guide wire therein, and the expansion lumen being arranged to semi-surround the main lumen. The expansion lumen has an inlet port radially outward from the catheter shaft and a discharge port arranged near the distal end of the catheter shaft. The discharge port is longitudinally arranged through the distal terminal end of the expansion lumen or is radially inwardly fluidly connected to the main lumen. A porous membrane is arranged at the discharge port to allow only gas to pass through it. The balloon is fixed around the outer surface near the distal end of the catheter shaft and coincides with the inlet port.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of U.S. Provisional Application No. 62 / 845,683, filed May 9, 2019; U.S. Provisional Application No. 62 / 845,699, filed May 9, 2019; U.S. Provisional Application No. 62 / 845,711, filed May 9, 2019; and U.S. Provisional Application No. 62 / 845,747, filed May 9, 2019, each of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to an intravascular medical system. In particular, the present invention relates to an improved balloon guide catheter in which residual air trapped in the balloon guide catheter is positively discharged when the balloon guide catheter is prepared by a physician or interventionalist before being introduced into the body. Background Art

[0004] Catheters are now widely used in conjunction with a variety of intravascular medical procedures or treatments. One such widely adopted use or application of intravascular catheters is in the medical procedure of thrombectomy after acute ischemic stroke (AIS), in which a sheath guide catheter (non-balloon guide catheter) or a balloon guide catheter is introduced into the internal carotid artery to serve as a conduit for auxiliary devices such as guidewires, microcatheters, stent retrievers, or intermediate catheters. The sheath guide catheter (non-balloon guide catheter) maintains access to the intended treatment location within the vessel and shortens the surgical time by facilitating multiple passes with auxiliary devices to reach the treatment location. The use of the balloon guide catheter provides the additional beneficial effect of blocking blood flow and achieving complete apposition of the vessel when expanded to the expanded state. As the stent retriever and / or direct aspiration catheter retracts into the balloon guide catheter along with the captured clot, blood flow blocking provides additional safety in limiting the blood pressure imposed on the clot and maximizing the aspiration performance during the aspiration phase. While such beneficial effects are obvious and clinically proven, the use of balloon guide catheters requires following some cumbersome preparation steps to eliminate residual air in the inflation lumen, which is replaced by the inflation medium in both the inflation lumen and the balloon. Despite such advantages, these preparation steps performed before the balloon guide catheter is introduced into the body completely prevent some physicians or interventionalists from using balloon guide catheters, instead choosing to use sheath guide catheters (non-balloon guide catheters) that do not require such preparation steps.

[0005] Prior to being introduced into a target vessel in the body, a physician or interventionalist will follow a multi-step process to prepare a conventional balloon guide catheter to properly purge residual air trapped therein. This preparation procedure typically requires applying a vacuum or negative pressure at the inflation port to remove the residual air, followed immediately by dispensing inflation media back into the catheter. This inflation lumen vacuum procedure may need to be repeated multiple times to ensure complete expulsion of the residual air. If the purging step is not followed correctly or skipped entirely, the residual air in the balloon guide catheter may be expelled into the vessel in the event of balloon failure, resulting in dangerous and detrimental effects to the patient.

[0006] Therefore, it is desirable to simplify the number of steps or operations to clear residual air from a balloon guide catheter, thereby increasing its desirability and ease of use while optimizing time efficiency and reducing the possibility of human error. Summary of the invention

[0007] One aspect of the present invention relates to an improved balloon guide catheter that minimizes the number of preparatory steps or operations to remove residual air from the device.

[0008] Another aspect of the present invention relates to an improved balloon guide catheter with positive discharge and methods of using such catheter of the present invention.

[0009] Another aspect of the present invention relates to an improved balloon guide catheter wherein the location of the deflation and inflation ports ensures that inflation of a balloon with inflation media occurs only when residual air is fully and completely deflated from the inflation lumen.

[0010] Yet another aspect of the present invention relates to an improved guide catheter wherein the inflation medium serves a dual function or purpose, initially serving to clear residual air from the inflation lumen and subsequently inflating the balloon once the residual air is cleared.

[0011] Yet another aspect of the present invention relates to an improved balloon guide catheter that, when prepared by a physician or interventionalist, allows for visual verification that the balloon has been properly purged of residual air prior to introduction into a patient.

[0012] It is yet another aspect of the present invention to provide an improved balloon guide catheter with positive venting in which residual air is purged prior to introduction into the body, thereby eliminating the need for vacuum or negative pressure during preparation.

[0013] One aspect of the present invention relates to a balloon guide catheter, which includes a catheter shaft having an outer surface, a proximal end, and an opposite distal end. The catheter shaft has a main lumen defined in the catheter shaft, which extends axially through the catheter shaft from the proximal end to the distal end. The main shaft is configured to receive a guide wire therein; the catheter shaft has an expansion lumen axially defined in the catheter shaft, which is arranged to semi-enclose the main lumen; the expansion lumen has an inlet port defined radially outward from the catheter shaft and at least one discharge port arranged near the distal end of the catheter shaft, wherein at least one discharge port is longitudinally arranged through the distal terminal end of the expansion lumen or is radially inwardly fluidly connected to the main lumen. The catheter also includes a porous membrane disposed at at least one discharge port, wherein the porous membrane has a plurality of holes defined in the porous membrane, and the size of these plurality of holes is set to allow only gas to pass through it. In addition, the catheter also has an expandable balloon, which is fixed around the outer surface of the catheter shaft near the distal end of the catheter shaft and coincides with the inlet port.

[0014] Another aspect of the present invention relates to a method of using a balloon guide catheter as described in the preceding paragraphs. The method comprises the following steps: prior to introducing the balloon guide catheter into a target vessel, preparing the balloon guide catheter by positively venting residual air distally from the inflation lumen and the expandable balloon through at least one vent.

[0015] Another aspect of the present invention relates to a method for manufacturing a forward distal discharge balloon guide catheter. The method includes the following steps: forming a tubular main liner to form a main lumen extending axially therethrough; the formed tubular main liner has an etched area and a polymer impact layer at a selected surface. A first opening is radially punched through the formed tubular main liner, and the first opening serves as a radial discharge port in fluid communication with the main lumen defined by the axially passing through the formed tubular main liner. The provided microporous membrane is etched and has a polymer impact layer at selected portions of both surfaces of the microporous membrane, and the microporous membrane is positioned to cover the punched discharge port defined in the formed tubular main liner. Under the application of heat, the formed tubular main liner is laminated to attach to the microporous membrane. Then, a polymer sheath is positioned above the laminated assembly including the mandrel, the formed tubular main liner and the microporous membrane; and heat shrinkage is applied to cause reflow of the polymer sheath, thereby bonding the polymer sheath to the etched / impact layer of the microporous membrane and to the etched / impact layer of the formed tubular main liner. In a similar manner, a tubular expansion liner having an expansion lumen extending axially therethrough is formed; the shaped tubular expansion liner having an etched area and a polymer impact layer at selected surfaces. A second opening is radially punched through the shaped tubular expansion liner, the second opening serving as a radial drain port in fluid communication with the expansion lumen defined axially through the shaped tubular expansion liner. The second opening of the shaped tubular expansion liner is longitudinally positioned relative to the first opening of the shaped tubular main liner. At least one sheath is applied around the shaped tubular expansion liner. Heat shrink is then applied to induce backflow of at least one outer sheath, thereby forming a fused assembly with the braid, the shaped tubular expansion liner, and the shaped tubular main liner. The heat shrink is then removed prior to attaching a balloon around the fused assembly. Optionally, in

[0016] Prior to the step of longitudinally positioning the second opening of the formed tubular expansion liner relative to the first opening of the formed tubular primary liner, the method may also include applying a braid or coil wrapped around: (i) the formed tubular primary liner, excluding the formed tubular expansion liner; (ii) the formed tubular primary liner and including the formed tubular expansion liner; or (iii) the formed tubular primary liner, wherein a portion of the braid wraps around the formed tubular expansion liner and another portion of the braid is disposed between the formed tubular primary liner and the formed tubular expansion liner. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features of the present invention will become more apparent from the following detailed description and accompanying drawings, in which examples of the present invention are illustrated, wherein like reference numerals refer to similar elements throughout the several views, and in which:

[0018] Figure 1A is a longitudinal cross-sectional view of a balloon guide catheter of the present invention having a forward distal discharge configuration; the balloon is shown in a collapsed state;

[0019] Figure 1B yes Figure 1A A radial cross-sectional view of the balloon catheter along the dotted line I(B)-I(B);

[0020] Figure 1C yes Figure 1B An enlarged view of the dashed area I (C);

[0021] Figure 1D yes Figure 1A A longitudinal cross-sectional view of a balloon guide catheter of the present invention, wherein the balloon is in a fully expanded state;

[0022] Figure 1E depicts a partial view of the distal end of an exemplary balloon guide catheter according to the present invention, wherein dual inflation lumens are arranged side by side;

[0023] Figure 1F depicts a partial view of a distal end of another exemplary balloon guide catheter according to the present invention, wherein a dual inflation lumen arrangement has one inflation lumen disposed above the main / central lumen and another inflation lumen positioned below the main / central lumen;

[0024] Figure 1G is an alternative configuration of an exemplary radial cross-sectional view of a catheter of the present invention, which shows an eccentrically arranged semi-enclosing inflation lumen and a main / guide lumen (the two lumens do not share the same center, are not concentric);

[0025] Figure 1H is another configuration of an exemplary radial cross-sectional view of a catheter of the present invention, depicting a concentrically arranged semi-enclosing inflation lumen and a main / guide lumen (both lumens share the same center);

[0026] Figure 2A is a schematic diagram of an alternative configuration of the balloon guide catheter of the present invention, in which the balloon is in a completely collapsed state;

[0027] Figure 2B yes Figure 2A A partial longitudinal cross-sectional view of a balloon guide catheter;

[0028] Figure 2C to Figure 2G Describes the manufacturing Figure 2A A series of sequential stages or steps during the balloon-guided catheterization of

[0029] Figure 3A is a partial longitudinal cross-sectional view of the sealing convex feature of the forward discharge balloon guide catheter of the present invention; wherein when the balloon is in an expanded state, residual gas is allowed to escape through the discharge port longitudinally arranged at the terminal end of the expansion lumen and through the porous membrane;

[0030] Figure 3B yes Figure 3AA partial longitudinal cross-sectional view of a balloon guide catheter of , wherein the balloon is in a collapsed state sealed against a bump to inhibit the passage of residual air proximally through the stoma;

[0031] Figure 4A is a partial longitudinal cross-sectional view of yet another configuration of a balloon guide catheter according to the present invention having an expandable distal tip including a plurality of expandable detachable fingers; wherein the balloon is depicted in an inflated state and the expandable distal tip in an expanded state;

[0032] Figure 4B yes Figure 4A A partial longitudinal cross-sectional view of a balloon guide catheter of the invention, wherein the balloon is in a collapsed state and the expandable distal tip is in a compressed state;

[0033] Figure 4C yes Figure 4B A radial cross-sectional view of the expandable distal tip of the catheter along line IV(C)-IV(C);

[0034] Figure 4D yes Figure 4A End view of the expandable distal tip of

[0035] Figure 4E is a top longitudinal view of another configuration of a balloon guide catheter according to the present invention, wherein a balloon enclosing an expandable distal tip is radially constrained by a restriction band; wherein the balloon is shown in a collapsed state and the expandable distal tip is in a compressed state;

[0036] Figure 4F yes Figure 4E a balloon guide catheter, wherein the balloon is shown in an inflated state and the expandable distal tip is in an expanded state;

[0037] Figure 4G is a top longitudinal view of yet another configuration of a balloon guide catheter according to the present invention, wherein the expandable distal tip is a plurality of fingers and the balloon is secured along a distal weld pattern between the fingers; wherein the balloon is depicted in a collapsed state and the expandable distal tip is in a compressed state;

[0038] Figure 4H yes Figure 4G a balloon guide catheter, wherein the balloon is in an inflated state and the expandable distal end is in an expanded state;

[0039] Fig. 4I yes Figure 4H A radial cross-sectional view of the distal end of the catheter along line IV(I)-IV(I);

[0040] Figure 5Ais a top longitudinal view of an assembled balloon guide catheter showing an exemplary braid configuration, wherein a portion of the braid is depicted as being radially outside of an expanded liner and another portion of the braid is depicted as being radially inside of the expanded liner; and depicting optional three separate polymeric sheaths disposed about each of the central liner, the braid, and the inner liner;

[0041] Figure 5B yes Figure 5A A longitudinal cross-sectional view of the catheter along the line V(B)-V(B);

[0042] Figure 5C yes Figure 5A A radial cross-sectional view of the catheter along the line V(C)-V(C);

[0043] Fig. 6A is a top longitudinal view of an alternative expandable distal tip of an assembled balloon guide catheter according to the present invention; wherein the expandable distal tip is an expandable mesh or braid; the expandable distal tip is shown in a compressed state with the balloon collapsed; and

[0044] Figure 6B yes Fig. 6A Top longitudinal view of the catheter with the expandable distal tip depicted in the expanded state with the balloon inflated. DETAILED DESCRIPTION

[0045] The terms "distal" or "proximal" are used in the following descriptions regarding positions or directions relative to a treating physician or medical interventionist. "Distal" or "distalward" is a position away from or in a direction away from a physician or interventionist. "Proximal" or "proximalward" or "proximally" is a position close to or in a direction toward a physician or medical interventionist. The terms "blockage," "clot," or "occlusion" are used interchangeably.

[0046] Conventional balloon catheters have a coaxial design, wherein a central lumen disposed centrally in the balloon catheter receives a guide wire passing therethrough, and an expansion lumen is disposed coaxially around the central lumen and completely / fully surrounds the central lumen. The balloon guide catheter of the present invention is designed such that the expansion lumen partially surrounds or semi-surrounds the main lumen, i.e., the expansion lumen does not completely surround the main lumen. In addition, the center of the expansion lumen may, but does not necessarily, share the same center as the main lumen. Figure 1G is an alternative configuration of an exemplary radial cross-sectional view of a catheter of the present invention, which shows an eccentrically arranged semi-enclosed inflation lumen and a main / guide lumen (the two lumens do not share the same center, are not concentric), while Figure 1His another configuration of an exemplary radial cross-sectional view of a catheter of the present invention, depicting a concentrically arranged semi-enclosing inflation lumen and a main / guide lumen (both lumens share the same center).

[0047] When traversing a tortuous path through the body's vasculature, the currently arranged expansion lumen provides improved deliverability across the entire shaft by providing a connectable shaft that cannot be provided by a complete / completely enclosed concentric (coaxial) conventional design because the concentric design must be substantially unconnected between the outer and inner shafts to provide a concentric lumen. In addition, the conventional concentric (coaxial) design of an expansion lumen surrounding a central lumen occupies a significant amount of significant cross-sectional area between the inner and outer surfaces of the catheter, which extends around the circumference of the catheter in a substantially uniform manner, compared to the partial / semi-enclosed design of the present invention, which may have a varying wall thickness between the inner and outer surfaces of the catheter, which varies around the circumference of the catheter and allows for a reduction in the cross-sectional area between the inner and outer surfaces of the catheter. This variation in wall thickness around the circumference of the catheter allows for a larger inner diameter for a given outer diameter when compared to a conventional fully / completely enclosed coaxial design because less material is required to define the expansion / collapse lumen for a given lumen cross-sectional area. Ideally, the inner diameter of the partial / semi-enclosed design of the present invention remains circular over the entire catheter shaft to accommodate auxiliary devices that are mainly longitudinally maintained in a circular shape, and the outer surface deviates from a circular shape to a slightly elliptical shape to accommodate an expansion / collapse lumen. For a given outer diameter, a larger inner diameter allows the catheter of the present invention to receive auxiliary devices with an outer diameter larger than that originally accommodated by a complete / completely enclosed concentric design with the same given outer diameter. In addition, for a given suction vacuum pressure, the larger inner diameter of the present invention's design will allow a larger suction (co-suction with the intermediate catheter) flow rate. A larger suction flow rate is used to enhance the reverse flow in the target treatment position, and to apply a larger suction force to the clot face in the blood vessel, thereby facilitating the successful retrieval of clots by suction alone or in combination with a stent thrombectomy device. It should be understood that the inner and outer surfaces of the partial / semi-enclosed design of the present invention may have an elliptical shape. It is also conceivable to maintain an additional embodiment of an outer circular shape with an internal elliptical shape. The embodiment with an internal elliptical shape will be advantageous in a balloon guide catheter when combined with an inner intermediate catheter with a circular shape, because additional volume is provided between the inner elliptical cross section of the balloon guide catheter and the outer circular cross section of the intermediate catheter, providing additional cross-sectional area between the catheters that can be used for aspiration flow. Therefore, when a given intermediate catheter with an outer circular shape is accommodated in a balloon guide catheter with a given outer diameter, the balloon guide catheter with an internal elliptical shape will allow a greater aspiration flow rate than the balloon guide catheter with an inner circular shape, especially for a concentric design, because the concentric design will also require the wall thickness of the catheter to have a larger cross-sectional area to accommodate the expansion / collapse lumen.

[0048] refer to Figure 1A The longitudinal cross-sectional view depicted, the forward venting balloon guide catheter of the present invention eliminates the need for vacuum or negative pressure that is typically required when preparing conventional devices. The balloon guide catheter of the present invention includes a catheter shaft or body 100 having a main / central lumen 105 defined longitudinally therethrough for receiving a guidewire or other auxiliary device. The catheter shaft or body 100 also defines an expansion lumen 110 disposed radially outward from the main / central lumen 105 and partially / semi-enclosing the main / central lumen (but not sharing a common center), such as Figure 1B The proximal end of the expansion lumen is in fluid communication with the expansion port 115. Figure 1A As shown, the inflation port 115 is generally angled radially outward relative to the port of the catheter body 100. A manual device (e.g., a syringe) 120 or an automatic pressure device can be attached at the proximal inflation port 115 to generate positive pressure by dispensing an inflation medium (e.g., a liquid) into the inflation lumen 110. The inflation medium is preferably a liquid solution, such as a solution containing water, distilled water, deionized water, heparin, saline, contrast media / contrast agent, or some combination thereof. In a preferred embodiment, the inflation medium is a solution of contrast media and saline, most preferably a solution of a 50:50 ratio of contrast media and saline. The inflation medium solution is typically stored at room temperature.

[0049] The inflation lumen 110 has one or more exhaust ports defined therein. These exhaust ports may be configured to exhaust / clear residual air trapped in the inflation lumen in the radial direction, the longitudinal direction, or both. Figure 1A In the example shown, residual air is purged from two vents 135, 135', both disposed toward the distal end 150 of the catheter. One of the vents 135 is disposed proximal to the distal tip or end 150 of the catheter and is defined radially inwardly in the catheter shaft or body 100, serving as a conduit for fluid communication between the inflation lumen 110 and the main / central lumen 105 for purged residual air. The other vent 135' is disposed longitudinally at the distal tip or end 150 of the inflation lumen 110. It is contemplated and within the intended scope of the present invention to alternatively have either a radial vent or a longitudinal vent, but not both. Furthermore, if the balloon catheter has a radial vent, more than one vent may be provided as desired.

[0050] A microporous membrane 140 covers each of the exhaust ports 135, 135', wherein the pores of the microporous membrane are sized to allow only gas (e.g., residual air) to pass therethrough, and liquid (inflation medium) dispensed through the inflation lumen is prevented from permeating through the porous membrane, thereby allowing pressure within the inflation lumen to build up and inflate the balloon as the volume within the balloon is filled with the inflation medium. Preferably, the microporous membrane is a grade (based on porosity and thickness) of sintered polytetrafluoroethylene (PTFE), such as sintered polytetrafluoroethylene (ePTFE), which allows air molecules to pass therethrough, but acts as a barrier to larger molecules such as water, saline, and contrast media due to the two properties of (i) a hydrophobic membrane and (ii) molar volume. The membrane is hydrophobic in nature and allows the membrane to repel relatively high tension (polar) fluids even in the presence of small pores in a non-pressurized system. On the other hand, gases readily pass through such membranes at relatively very low pressures. For example, water vapor will pass through an ePTFE microporous membrane, however it is time dependent. With respect to the second factor, the size of water and contrast media molecules is larger than that of air molecules which allows air molecules to pass through a membrane containing many small pore sizes. With respect to the present invention, the relative size of the molecules is the primary feature that comes into play within the time frame of this patent application for fluid infusion through a lumen where air is expelled through a microporous membrane at a relatively high pressure. The micropores of the ePTFE microporous membrane vary in size and are preferably in the size range of about 0.02 μm to about 500 μm, more preferably in the size range of about 5 μm to about 100 μm. Figure 1C yes Figure 1B An enlarged view of the dashed area I(C) in FIG. 1 clearly shows the microporous membrane 140 covering the radially arranged discharge ports 135. Figures 1A to 1C In the embodiment, the microporous membrane 140 is radially arranged outside the central lumen 105 (ie, inside the expansion lumen 110). As required, the microporous membrane may be arranged inside the expansion lumen ( Figures 1A to 1C ); the microporous membrane may be completely disposed within the wall between the central lumen 105 and the expansion lumen 110, respectively; or a combination thereof, wherein a first portion of the microporous membrane extends radially inwardly into the wall between the expansion lumen and the central lumen, and a second portion of the microporous membrane extends radially outwardly into the expansion lumen. Preferably, no portion of the microporous membrane extends radially inwardly into the central lumen, as this could potentially cause an obstruction when passing the auxiliary device.

[0051] The inflation lumen 110 extends axially through the catheter body 100 from near its proximal end 145 to its opposite distal tip or end 150. An inflation port 130 is defined radially outward through the catheter body 100 and serves as a conduit for an inflation medium between the inflation lumen 110 and a balloon 125 covering the inflation port 130. The balloon 125 is bonded or adhered to the outer surface of the distal portion of the catheter body 100, thereby forming a seal over the inflation port 130. Figure 1AIn the collapsed state shown, balloon 125 is in physical contact against inflation port 130 , thereby temporarily preventing the passage of inflation medium therethrough until the accumulated pressure in inflation lumen 110 exceeds a predetermined pressure of the opposing force exerted by balloon 125 .

[0052] Figures 1A to 1C The embodiment shown in depicts a balloon catheter of the present invention having a single inflation lumen. Having more than one inflation lumen is possible and within the intended scope of the present invention. Figure 1E A dual inflation lumen design 110', 110" is depicted, wherein two inflation lumens are arranged side by side. In the first inflation lumen 110', fluid flows through the lumen from the proximal end to the distal end, while fluid flows through the second inflation lumen 110" in the opposite direction from the distal end to the proximal end. Figure 1F Another configuration of a dual inflation lumen design is shown in . Here, one of the dual inflation lumens is disposed above the main / central lumen and the other lumen is disposed below the main / central lumen. That is, the first inflation lumen 110' is disposed above the main / central lumen 105 and the second inflation lumen 110" is disposed below the main / central lumen 105. The first inflation lumen 110' having fluid flowing therethrough from the distal end to the proximal end has a microporous membrane 140 at the port to allow residual gas to pass through, but when the residual air has been purged, exhausted or driven out of the system, the inflation medium is prohibited from passing through the membrane, thereby causing the balloon to inflate.

[0053] The perspective view and the longitudinal cross-sectional view of the assembled catheter according to the present invention are respectively suitable for Figure 2A and 2B In. Figures 2C to 2G Describes the assembly and manufacturing Figure 2A and 2B A series of sequential steps or phases during the catheterization process shown. Initially, Figure 2C In the embodiment of the present invention, the main / central lumen 105 can be formed by wrapping a main / central liner 210 (e.g., made of PTFE) around a mandrel 205 to produce a shaped main / central tube. Preferably, the mandrel 215 is a silver-plated (SPC) mandrel impregnated with a PTFE layer with a wall thickness (typically about 0.00075" to about 0.001") and then etched. A polymer impact layer (e.g., polyether block amide) is applied. The polymer strike layer may have a wall thickness of a few thousandths of an inch, but for the present application, a thickness of about 0.00025" will be sufficient to communicate and adhere to the return polymer jacket material, as described in detail below. Alternatively, a preformed tube may be used as the main / central tube. A first hole or opening is radially punched through the formed tubular main / central liner 210 (PTFE on SPC mandrel) which serves as a radial drain port 135 into the main / central lumen 105. The formed micro-porous material of the selected grade (based on the desired porosity and thickness) is cut from a patch or from a tubular configuration. The sintered PTFE of the microporous membrane 140 is provided to facilitate easier installation and positioning around the mandrel 205 and the formed tubular main / center liner 210. Selected portions or the entire surface on both sides of the microporous membrane 140 may be treated (e.g., etched using conventional techniques) to facilitate application of a thin polymer impact layer at selected portions or edges of the microporous membrane 140, along which the microporous membrane forms an inherent weld with the catheter polymer substrate. Similar to the microporous membrane, the formed tubular PTFE main / center liner 210 is also treated (e.g., etched) and prepared with a polymer impact layer. See Figure 2D , the cut microporous membrane 140 is positioned (preferably centrally located) above the punched vent 135 defined in the shaped tubular PTFE main / center liner 210. The shaped tubular PTFE main / center liner 210 is then attached (e.g., welded or bonded) to the cut microporous membrane 140 with the application of heat during the lamination construction process step of the catheter.

[0054] like Figure 2E As shown, using a wire braiding machine, a braid or coil 155 is tightly applied or wrapped around the assembled SPC impregnated mandrel 205 with the shaped tubular ePTFE main / center liner 210 and the ePTFE microporous membrane patch 140. The braid 155 provides structural support as well as holding the ePTFE microporous membrane patch 140 to the tubular shaped ePTFE main / center liner 210. Then, a polymer sheath material 235 with scraping ports is directly located above the scraping portion. Figure 2F In the embodiment of the present invention, a heat shrink is positioned over the assembly and heat is applied to cause the materials to reflow and bond together before the heat shrink is removed. Preferably, a fluorinated ethylene propylene (FEP) heat shrink is slid over the assembly and heat is applied to cause the polymer jacket material 235 to reflow to bond to the braid of the membrane, the etched / strike portion, and to the strike layer covering the PTFE.

[0055] A separately formed expansion liner 410 (eg, PTFE) is wrapped around its own inner mandrel (eg, SPC mandrel) to form the expansion lumen 110, such as Figure 5AAs shown. The shaped tubular expansion liner can be positioned above the braid, below the braid, or between the braid strands (i.e., a portion of the braid is above the shaped tubular expansion liner and another portion of the braid is below the shaped tubular expansion liner). Alternatively, a preformed tube can be used as the shaped tubular expansion liner. The shaped tubular ePTFE expansion liner can be longitudinally positioned relative to the shaped tubular main / center liner. In one configuration, the shaped tubular expansion liner and the main / center liner are arranged so that the ePTFE microporous membrane 140 and the expansion port 130 leading to the balloon 125 are substantially radially aligned with the radial exhaust port 135 (e.g., Figure 2A and 2B Alternatively, Figure 1A As shown, the microporous membrane 140 and inflation port 130 do not need to be radially aligned with the radial vent 135. When subjected to the FEP heat shrink process, the assembled outer sheath, braid, inflation lumen and liner fuse together during reflow. Prior to attaching the balloon, the FEP heat shrink is removed. Figure 2G The balloon 125 in the catheter is positioned over the fused assembly of the outer sheath, braid, inflation lumen and liner so that the balloon covers the inflation port 130. The two ends of the balloon are then heat welded to form a built-in weld with the outer surface of the catheter shaft or body 100.

[0056] See also Figure 5A Several additional thermoplastic outer tubes, sleeves or sheaths (500, 500', 500") of varying Shore hardness may be positioned over the respective main / central liner 210, braid 455 and expansion liner 410 to tailor the finished catheter stiffness profile as desired. The sheaths are placed one after the other to vary the stiffness of the catheter along its length. The sheaths of varying hardness are arranged over the central lumen, braid and expansion lumen assembly, with each sheath being arranged to be longitudinally serially adjacent (in physical contact) against the next sheath, or space may be left for material to flow between adjacent sheaths. A single outer sheath disposed longitudinally allows for a thin wall thickness that is a function of how thin the wall thickness can be extruded for a particular material. These sheaths are reflowed through the braid pattern and bonded to the impact layers of the central lumen and expansion lumen. The reflow process involves threading FEP heat shrink tubing over the assembly, applying heat to reflow the sheaths, and then removing the FEP heat shrink. The balloon is then heat welded to the assembly. Radially disposed outer sheaths are possible.

[0057] Once the components are assembled and positioned as desired, an insert is preferably placed to prevent sealing of the openings during heating, thereby maintaining fluid connectivity in the following areas: (i) at the ends of the inflation lumen; (ii) between the balloon and the inflation lumen; and (iii) between the inflation lumen and the PTFE microporous membrane. Heat is applied, whereby the thermoplastic material reflows to form a fixed assembly while the insert inhibits sealing of the communication passage. Finally, the insert is removed and the balloon 125 is assembled (e.g., heat welded) to the fixed assembly. Figure 2A and 2B In the configuration of , the distal end of the balloon 125 is sealed within the wall of the catheter (i.e., between the PTFE center liner and the outer sheath). The balloon 125 is then inverted and its proximal end is laser welded to the outer surface of the assembled catheter body. Figure 1A In the depicted alternative configuration, the balloon is laser welded to the outer surface of the catheter shaft at both its proximal and distal ends, rather than wrapping around the distal end or tip 150. A Luer or other connector 160 may be attached to the proximal end of the assembled catheter.

[0058] The location of the inflation / venting ports promotes complete venting of residual air, and only when the residual air has been completely expelled is the balloon inflated with the inflation medium initially used to vent the residual air in the catheter. To facilitate this, the inflation port size and the venting port size are preferably optimized so that the pressure required to inflate the balloon is greater than the pressure required to vent the residual air.

[0059] exist Figures 2A to 2G In the embodiment of the present invention, the braid 155 is wrapped around the outer periphery of the assembled shaped tubular PTFE main / center liner and the ePTFE microporous membrane secured thereto to hold the microporous membrane in place. The ePTFE microporous membrane may be positioned above the braid in other ways, i.e., the braid wraps around the outer periphery of the shaped tubular main / center liner completely radially inward (i.e., below / under) the shaped tubular expansion liner. While in another design, the braid may wrap around the outer periphery of the assembled shaped tubular PTFE main / center liner, the ePTFE microporous membrane, and the shaped tubular expansion liner. In another configuration, a portion of the braid may be wrapped radially inward (i.e., below / under) the shaped tubular expansion liner (i.e., between the shaped tubular expansion liner and the shaped tubular main / center liner), and another portion may be wrapped radially outward (i.e., above / on) the shaped tubular expansion liner (e.g., between the shaped tubular expansion liner and the shaped tubular main / center liner). Figure 5A ).

[0060] The positively discharged balloon guide catheter of the present invention is prepared by a physician or interventionalist before being introduced into the body. Specifically, a syringe 120 containing an expansion medium is connected to the expansion lumen 110 via an expansion port 115. As the physician or interventionalist uses the syringe 120 to dispense the expansion medium into the expansion lumen 110, the residual air therein is pushed through the expansion lumen 110 in the distal direction by the expansion medium. Since the residual air is pushed forward through the expansion lumen by the expansion medium, the need for vacuum or negative pressure when removing the residual air from the catheter is eliminated. In more detail, initially, when the balloon collapses and is tightly wrapped in a manner of physical contact against the outer surface of the catheter body, the residual air follows the route or path of least resistance through the microporous membrane 140 and through the discharge ports 135, 135' to leave the catheter body. As the expansion medium is introduced into the expansion port, only the residual gas (e.g., air) permeates through the microporous membrane 140 and outwardly through the corresponding radially and longitudinally configured discharge ports 135, 135'. Because the microporous membrane 140 prohibits the liquid inflation medium from permeating therethrough, initially the pressure in the inflation lumen 110 remains equal or constant to a certain extent due to the fact that the residual gas (e.g., air) previously trapped in the catheter passes through the porous membrane and outwardly from the vents 135, 135'. However, once the residual gas (e.g., air) in the catheter is vented, the continued distribution of the pressurized inflation medium into the inflation lumen causes a pressure buildup at the inflation port 130, thereby exerting a radially outward force on the balloon 125, which in turn causes the balloon to expand radially outward when filled with the inflation medium. Figure 1A The balloon 125 is shown in a collapsed state; and Figure 1D The balloon is shown in a fully inflated state when residual air has been purged from the catheter and inflation medium has completely filled the balloon.

[0061] Figure 1A Only one inflation opening 130 is shown, but more than one inflation opening is contemplated and within the intended scope of the present invention for faster inflation / expansion of the balloon 125. Figure 1A As shown), the balloon 125 is in physical contact with the outer surface of the catheter body, thereby sealing the inflation port 130 so that the expelling medium cannot pass therethrough until the pressure applied to the balloon at the inflation port 130 exceeds a predetermined threshold.

[0062] The alternative configuration of the main / central lumen 305 and the partially / semi-enclosed inflation lumen 310 of the balloon guide catheter of the present invention is Figure 3A345 and 350. The balloon 325 is directly laser welded to the catheter shaft or body 300 at its proximal end, and at its opposite distal end of the balloon 325, a distal hole 340 (e.g., a microporous membrane or a plurality of longitudinal openings) is arranged at the junction between the outer surface of the balloon and the catheter body. The microporous membrane 340 is similar to the microporous membrane described in detail with respect to the previous embodiment, and only allows residual gas (e.g., residual air) to pass through it, thereby prohibiting any liquid / solution (e.g., expansion medium) from passing through. A bump, protrusion, convexity or other convex surface 375 extends radially outward from the outer surface of the catheter body and is positioned at the proximal side of the microporous membrane 340. During the preparation of the balloon guide catheter before inserting the blood vessel, the device is positioned so that the distal end faces upward. When the inflation medium is injected through the inflation lumen, the residual gas is directed over the bump, protrusion, convexity or other raised surface 375 with a slight expansion in the balloon 325 and exits through the microporous membrane 340. Once the air escapes, the passage of the inflation medium is blocked by the microporous membrane 340, and the balloon 325 is fully inflated as the pressure increases. However, the physician or interventionalist only needs to partially inflate the balloon 325 until there is no visible residual gas in the balloon. Prior to insertion into the body, the inflation medium is retracted into the syringe under negative pressure / vacuum and the balloon 325 collapses. The balloon 325 forms a seal against the bump, protrusion, convexity or other raised surface 375 when in the collapsed state, thereby preventing gas from returning to the balloon in the proximal direction, thereby maintaining the lumen cleared of air in the collapsed state prior to insertion into the body.

[0063] In another variation of the configuration of a balloon catheter according to the present invention, the assembled catheter body at its distal end may be configured to have an expandable distal end or tip 450, such as Figures 4A to 4D . The expandable distal end or tip of the catheter is in an expanded state having a larger diameter relative to its smaller diameter when the balloon is inflated, and in a compressed state when the balloon is collapsed. Specifically, the expandable distal end or tip 450 is divided into a plurality of separable expandable fingers 480 that can be radially compressed together by the overmolded balloon 425. In this particular configuration, rather than substantially conforming to the outer contour of the expandable fingers, in the inflated state, the overmolded balloon is stretched taut across the tips or ends of the fingers and is in physical contact only therewith (without physical contact of the balloon between the fingers). Figure 4A and 4BIn the configuration shown, the balloon is welded or fixed only around the outer periphery of the catheter shaft distal to the porous membrane 440, thereby coinciding with the perforations through the primary liner 210 and the outer sheath 500. Other attachment methods are contemplated and are within the intended scope of the present invention for fixing the balloon around the expandable detachable fingers, such as adhesive bonding or heat fusion, which will be further described in detail. The expandable distal end or tip 450 of the catheter can be divided into any number of two or more expandable detachable fingers 480 as needed. The more fingers 480 there are, the shorter the distance that the expandable material between adjacent detachable fingers needs to be separated from each other when the balloon of the catheter is inflated with an expansion medium. The smaller the fingers 480, the larger the diameter to which the fingers will expand. The space between the fingers can be adjusted as needed. That is, the space between adjacent fingers can be increased to allow sufficient expandable material so that the force to expand the material is relatively small; the space between adjacent fingers can be reduced so that the expandable material reaches maximum expansion at a predetermined diameter. The fingers may optionally include features that help minimize lateral bending forces to optimize flexibility when navigating tortuous paths.

[0064] Prior to dispensing inflation medium into inflation lumen 405, balloon 425 is in a collapsed state and expandable distal end or tip 450 of the catheter is in a radially compressed state, such as Figure 4B . When in this radially compressed state, adjacent fingers 480 are spaced at a minimum distance so that the outer diameter of the distal end or tip is less than or equal to the outer diameter of the remainder of the catheter. When the balloon 425 is in the collapsed state, the balloon is tightened in physical contact against the bump 475 that acts as a collapse seal to inhibit residual gas (e.g., air) from returning to the balloon 425 in the proximal direction through the vent 485.

[0065] See also Figure 4A During expansion, the balloon 425 expands radially and contracts longitudinally, thereby pulling the expandable distal tip 450 proximally and expanding the distance spacing between adjacent fingers 480. With such an expanded distal end or tip, a wider mouth is provided on the distal end of the catheter for suction and provides greater suction force when engaging the clot. Once the clot is engaged, the suction force can be maintained while the balloon collapses and the distal mouth radially compresses the clot to help clamp the clot for extraction through a larger guide or balloon guide catheter. The thickness of the balloon can be varied as desired to define a specific expansion profile for the balloon and expandable distal end or tip 450.

[0066] Figure 4C yes Figure 4B A radial cross-sectional view of the four fingers of the catheter in FIG. 5 along line IV(C)-IV(C) with the fingers in a compressed state (reduced diameter) and the balloon collapsed. Figure 4DAnother view in the Figure 4A An end view of the expandable distal tip in FIG. 1 and, in particular, depicts the four fingers of the expandable distal end or tip in an expanded state (increased diameter) with the balloon inflated.

[0067] A restraining band 495 may be disposed around the balloon proximal to the expandable distal end or tip 450 ( Figure 4E ) to radially limit the diameter of the balloon when inflated, e.g. Figure 4F As shown. If a radiopaque material is selected for the restriction band 495, the band can serve the dual purpose of a marker during navigation of the catheter to the target site in the blood vessel. The balloon 425 is adhered or fixed to the outer surface of the catheter shaft proximally, thereby enclosing the fingers 480 distally without being fixed (separately) under the restriction band 495 in any way. Therefore, during the expansion / collapse of the balloon 425 with the expansion medium, any sliding movement of the balloon 425 under the restriction band 495 is unimpeded and allowed. As the balloon 425 is inflated with the expansion medium, the pressure within the balloon increases (as shown by the "IP" arrow), causing the diameter of the balloon to increase, which in turn applies tension to the balloon material (as shown by the "T" arrow), causing the fingers to open or separate, thereby increasing the diameter of the expandable distal tip. Preferably, the expandable distal tip or end 450 is inflated to an outer diameter that is greater than the outer diameter of the inflated balloon.

[0068] Another alternative configuration of the expandable distal tip or end of the catheter is Figure 4G and 4H In this particular design, the proximal end of the balloon is proximally secured to the outer surface of the catheter shaft, while the opposite end of the balloon is distally secured (e.g., bonded or welded) between the fingers. Such a distal weld pattern (shown in dashed lines) advantageously seals the balloon and facilitates expansion of the fingers during inflation, as shown in FIG. Figure 4H as well as Figure 4H Mid-distal expandable tip Fig. 4I As shown in the distal end view of FIG.

[0069] A final configuration of an expandable distal end or tip of a catheter is Fig. 6A and 6B4, wherein the fingers are replaced by an expandable cage, mesh or braid 480' attached to the distal end of the catheter shaft. The proximal end of the balloon 425 is fixed to the outer surface of the catheter shaft, while its opposite distal end encapsulates the braid 480' and is connected to the distal end of the main shaft via the braid. By selecting a specific braid pattern and the desired degree of expandability of the expandable balloon material above the expandable distal end, the braid 480' is pulled apart (i.e., the diameter increases) as the balloon is expanded / expanded with an expansion medium. It should be noted that there is no portion of the shaped tubular PTFE main / central liner at the distal end or end of the catheter that is intended to be expanded (i.e., does not extend into that portion distally) because this will limit the expansion of the distal end or end, however, the distal terminal end of the shaped tubular PTFE main / central liner can be extended axially to the position where the expandable distal end or end is hinged to the distal end of the catheter shaft and thus enhance the position. Furthermore, the distal end of the balloon may be inverted at the distal tip of the catheter where the distal end of the balloon extends proximally to encapsulate the braid.

[0070] In each of the embodiments of the invention described herein, the balloon catheter of the present invention will be prepared by purging the device prior to introduction into the body, as the residual air is vented distally from the catheter. Failure to purge the catheter prior to introduction into the body will result in the undesired entry of the vented residual air into the vascular system, potentially causing harm to the patient. The positive venting system associated with the balloon guide catheter of the present invention simplifies the preparatory steps for purging the residual air from the device, thereby minimizing the frustration of the physician or interventionalist when using the device.

[0071] Therefore, although the basic novel features of the present invention as applied to its preferred embodiments have been shown, described and pointed out, it should be understood that various omissions, substitutions and changes in form and detail may be made to the illustrated system / device and its operation by those skilled in the art without departing from the spirit and scope of the present invention. For example, it is clearly intended that all combinations of those elements and / or steps that perform substantially the same functions in substantially the same manner to achieve the same results are within the scope of the present invention. It is also fully expected and conceivable that elements are replaced from one described embodiment to another. It should also be understood that the drawings may not be drawn to scale, but they are merely conceptual in nature. Therefore, it is intended to be limited only as indicated by the scope in the appended claims.

[0072] Each issued patent, pending patent application, publication, journal article, book, or any other reference cited herein is each incorporated by reference in its entirety.

Claims

1. A balloon guide catheter, comprising: a catheter shaft having an outer surface, a proximal end, and an opposite distal end; The catheter shaft has a main lumen defined therein, the main lumen extending axially through the catheter shaft from the proximal end to the distal end; the main lumen being configured to receive a guidewire therein; The catheter shaft has an inflation lumen axially defined therein, the inflation lumen being arranged to semi-surround the main lumen; the inflation lumen having an inlet port defined radially outward from the catheter shaft and at least one exhaust port disposed proximate the distal end of the catheter shaft; The at least one vent is disposed longitudinally through the distal terminal end of the inflation lumen or is in radially inward fluid communication with the main lumen; a porous membrane disposed at the at least one discharge port; the porous membrane having a plurality of pores defined therein, the plurality of pores being sized to allow only gas to pass through the plurality of pores; and An expandable balloon is secured about the outer surface of the catheter shaft near the distal end of the catheter shaft and coincident with the inlet port.

2. The balloon guide catheter of claim 1, wherein the catheter shaft comprises a shaped tubular primary liner through which the main lumen extends longitudinally; the catheter shaft further comprises a shaped tubular expansion liner through which the expansion lumen extends longitudinally; and wherein the at least one drain port is arranged to be in radially inward fluid communication with the main lumen; and the balloon guide catheter further comprises a reinforcing member; wherein the reinforcing member is a braid or a coil; and wherein the reinforcing member is arranged around: (i) only the shaped tubular main lining; (ii) only the assembly of the shaped tubular main lining and the porous membrane; or (iii) the assembly of the shaped tubular main lining, the porous membrane and the shaped tubular expansion liner.

3. A balloon guide catheter according to claim 1, wherein the at least one discharge port is longitudinally arranged through the distal terminal end of the inflation lumen; and the balloon guide catheter also includes a protrusion, which is radially arranged outward from the outer surface of the catheter shaft, coincides with the inlet port and is positioned proximal to the longitudinally arranged discharge port; wherein the balloon physically contacts the protrusion when in a collapsed state, thereby preventing air from passing through it in a proximal direction.

4. The balloon guide catheter according to claim 1 further includes an expandable distal tip mounted to the distal end of the catheter shaft; and the proximal end of the expandable balloon is fixed to the outer surface of the catheter shaft, while the opposite distal end of the expandable balloon encapsulates the expandable distal tip; the expandable distal tip changes from a compressed state having a first diameter when the expandable balloon is collapsed to an expanded state having a second diameter greater than the first diameter when the expandable balloon is expanded.

5. A balloon guide catheter according to claim 4, wherein the expandable distal tip is a plurality of expandable detachable fingers; the expandable balloon is (i) fixed to the expandable distal tip but not between the expandable detachable fingers; or (ii) fixed along each of the plurality of expandable detachable fingers of the expandable distal tip and located between them.

6. The balloon guide catheter according to claim 4 further includes a resistance band arranged around the expandable balloon proximal to the expandable distal end; the expandable balloon is separated from the resistance band to allow the expandable balloon to move freely under the resistance band.

7. The balloon guide catheter of claim 4, wherein the expandable distal tip is an expandable braid mounted to the distal end of the catheter shaft.

8. A method of using a balloon guide catheter; wherein the balloon guide catheter has a catheter shaft, the catheter shaft having an outer surface, a proximal end and an opposite distal end; the catheter shaft has a main lumen defined in the catheter shaft, the main lumen extending axially through the catheter shaft from the proximal end to the distal end; the main lumen is configured to receive a guide wire in the main lumen; the catheter shaft also has an expansion lumen axially defined in the catheter shaft, the expansion lumen is eccentrically arranged relative to the main lumen; the expansion lumen has an inlet port defined radially outward from the catheter shaft and is arranged near the catheter shaft. at least one discharge port at the distal end of the expansion lumen; the at least one discharge port is longitudinally arranged through the distal terminal end of the expansion lumen or is fluidly connected radially inwardly with the main lumen; the balloon guide catheter also includes a porous membrane arranged at the at least one discharge port; the porous membrane has a plurality of holes defined in the porous membrane, and the size of the plurality of holes is set to only allow gas to pass through the plurality of holes; and the balloon guide catheter also includes an expandable balloon, which is fixed around the outer surface of the catheter shaft near the distal end of the catheter shaft and coincides with the inlet port; the method comprises the following steps: Prior to introducing the balloon guide catheter into a target vessel, the balloon guide catheter is primed by positively venting residual air distally from the inflation lumen and the expandable balloon through the at least one vent.

9. A method according to claim 8, wherein the catheter shaft includes a shaped tubular main lining extending longitudinally through the main lumen; the catheter shaft also includes a shaped tubular expansion liner extending longitudinally through the expansion lumen; wherein the at least one discharge port is configured to be fluidically connected to the main lumen radially inward, and the balloon guide catheter also includes a reinforcing member; wherein the reinforcing member is a braid or a coil; and wherein the reinforcing member is arranged around: (i) only the shaped tubular main lining; (ii) only the assembly of the shaped tubular main lining and the porous membrane; or (iii) the assembly of the shaped tubular main lining, the porous membrane and the shaped tubular expansion liner.

10. The method according to claim 8, further comprising the steps of: Upon collapsing the expandable balloon, the collapsed balloon, in physical contact with a seal against a bump, prevents proximally returning air from passing through the at least one vent, the at least one vent being longitudinally disposed through the distal terminal end of the inflation lumen, the bump being disposed radially outward from the outer surface of the catheter shaft, coincident with the inlet port and positioned proximal to the longitudinally disposed vent.

11. The method of claim 8, wherein the balloon guide catheter further comprises an expandable distal tip mounted to the distal end of the catheter shaft; and a proximal end of the expandable balloon is fixed to the outer surface of the catheter shaft, and an opposite distal end of the expandable balloon encapsulates the expandable distal tip; the method further comprising the steps of: The expandable distal tip is transitioned from a compressed state having a first diameter when the expandable balloon is collapsed to an expanded state having a second diameter greater than the first diameter when the expandable balloon is inflated.

12. A method according to claim 11, wherein the expandable distal tip is a plurality of expandable detachable fingers; the expandable balloon is (i) fixed to the expandable distal tip but not between the expandable detachable fingers; or (ii) fixed along each of the plurality of expandable detachable fingers of the expandable distal tip and located between them.

13. The method of claim 11, wherein the balloon guide catheter further comprises a resistance band disposed around the balloon proximal to the expandable distal tip; the expandable balloon being separated from the resistance band so as to allow the expandable balloon to move freely beneath the resistance band.

14. The method of claim 11, wherein the expandable distal tip is an expandable braid mounted to the distal end of the catheter shaft.

15. A method for manufacturing a forward distal discharge balloon guide catheter, the method comprising the steps of: forming a shaped tubular primary liner to form a main lumen axially extending through the shaped tubular primary liner; The shaped tubular primary liner has etched areas and a polymer strike layer at selected surfaces; punching a first opening radially through the formed tubular primary liner, the first opening serving as a radial drain port in fluid communication with the main lumen defined axially through the formed tubular primary liner; providing a microporous membrane having etched regions and a polymer strike layer at selected portions of both surfaces of the microporous membrane; positioning the microporous membrane to cover the punched drain port defined in the formed tubular primary liner; as well as The formed tubular primary liner is laminated to attach to the microporous membrane with the application of heat.

16. The method according to claim 15, further comprising the steps of: positioning a polymeric sheath over a laminate assembly comprising a mandrel, said formed tubular primary liner, and said microporous membrane; as well as Heat shrink is applied to induce reflow of the polymeric jacket, thereby bonding the polymeric jacket to the etched areas / surge layers of the microporous membrane and to the etched areas / surge layers of the formed tubular primary liner.

17. The method according to claim 16, further comprising the steps of: forming a shaped tubular expansion liner to form an expansion lumen axially extending through the shaped tubular expansion liner; the shaped tubular expansion liner having an etched area and a polymer strike layer at selected surfaces; punching a second opening radially through the formed tubular expansion liner, the second opening serving as a radial drain port in fluid communication with the expansion lumen defined axially through the formed tubular expansion liner; longitudinally positioning the second opening of the formed tubular expansion liner relative to the first opening of the formed tubular primary liner; applying at least one outer sheath around said shaped tubular expansion liner; applying heat shrink to cause reflow of the at least one outer jacket to form a fused assembly with the braid, the shaped tubular expansion liner, and the shaped tubular primary liner; as well as The heat shrink is removed prior to attaching the balloon around the fused assembly.

18. A method according to claim 17, wherein before the step of longitudinally positioning the second opening of the formed tubular expansion liner relative to the first opening of the formed tubular main liner, it also includes the step of applying a braid or coil wrapped around: (i) the formed tubular main liner, excluding the formed tubular expansion liner; (ii) the formed tubular main liner and including the formed tubular expansion liner; or (iii) the formed tubular main liner, wherein a portion of the braid wraps around the formed tubular expansion liner and another portion of the braid is disposed between the formed tubular main liner and the formed tubular expansion liner.

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