Intravascular Catheters

Abstract

To provide an intravascular catheter.SOLUTION: An intravascular catheter includes a distal porous cuff section having a plurality of unobstructed openings defined radially outward from an annular inflation chamber, where the distal porous cuff section is non-rotatable. The catheter also includes a tubular body disposed proximally to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section with an inner lumen defined axially therethrough. The sidewall of the tubular body has an inflation supply channel extending in a direction parallel to an axial direction of the intravascular catheter.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to intravascular catheters, and more particularly to intravascular catheters for capturing and retrieving thrombi or clots or other material that obstructs flow through a blood vessel. [Background technology]

[0002] Acute ischemic stroke is primarily caused by a thrombotic or embolic obstruction (e.g., blockage) in an artery of the brain. The obstruction is typically caused by a blood clot that has dislodged from another part of the body and travels antegrade (in the direction of normal blood flow) through the blood vessels, eventually lodges in a neurovascular artery, where it blocks blood flow to a particular region of the brain.

[0003] A procedure known as thrombectomy can be used to remove thrombi, obstructions, blockages, or clots lodged in blood vessels using a mechanical retrieval device. In a thrombectomy procedure or treatment, a physician or interventionalist introduces a guidewire and a microcatheter together into the blood vessel through the vasculature in an artery typically located in the groin or arm, or by direct access through the carotid artery. The guidewire and microcatheter are advanced together to a location proximal to the targeted clot, blockage, or blockage. The guidewire is then advanced across the clot, followed by the microcatheter. While in a compressed state, a mechanical thrombectomy device may be guided through the lumen of the microcatheter to the target site. After exiting the microcatheter, the mechanical thrombectomy device typically automatically expands to its original expanded state. Mechanical thrombectomy devices are typically made of self-expanding biocompatible materials, such as nickel-titanium. Aspiration through the catheter may be used in conjunction with or instead of the mechanical retrieval device to remove the clot.

[0004] During retrieval of the blockage, it is preferable to bring the distal end or tip of the catheter as close as possible to the outer or external surface of the thrombus, obstruction, blockage, or clot. It is desirable to minimize friction therebetween (i.e., low friction) to improve maneuverability of the catheter through tortuous vascular pathways while reducing trauma to tissues of the inner wall of the blood vessel. Typically, friction is reduced by applying a hydrophilic coating or other lubricious coating, such as silicone, polytetrafluoroethylene (PTFE), polyvinylpyrrolidone (PVP), to the outer surface of the catheter. However, the use of such low-friction coatings may have one or more associated drawbacks, such as a tendency to spread to undesired areas and / or easily degrade / destroy undesired downstream particulate matter. A low-friction surface on the inner surface of the distal portion of the catheter is also desirable to minimize shear forces on the clot as it is retrieved by the catheter. Additionally, it may be desirable to enlarge / expand the diameter of the distal tip or end of the clot retrieval catheter to optimize complete clot retrieval, resulting in higher first-pass recanalization success. Simply enlarging or expanding the distal tip may increase the stiffness of the catheter and therefore unnecessarily impede beneficial flexibility during navigation through the blood vessels to the target site. Summary of the Invention [Problem to be solved by the invention]

[0005] It would therefore be desirable to develop an improved intravascular catheter that overcomes these aforementioned drawbacks. [Means for solving the problem]

[0006] One aspect of the present invention is directed to a low-friction intravascular catheter in which friction between the distal portion / section / tip / end of the catheter and the inner wall of the blood vessel is minimized such that the catheter is easily advanced through the tortuous path of the blood vessel to a position at the face of the clot.

[0007] Another aspect of the present invention relates to an intravascular catheter having a distal section that is expandable / expandable when positioned in proximity to the clot to optimize complete clot collection, resulting in higher first-pass recanalization success and minimizing the incidence of distal emboli, and further wherein the catheter maintains its flexibility by having the distal section remain in a non-expanded / non-expanded state while navigating through a tortuous path to the target clot.

[0008] Yet another possible embodiment of the present invention relates to an intravascular catheter in which at least a portion of the distal section of the catheter is expandable / expandable to increase in diameter in order to make physical contact with the inner wall of the blood vessel and form a seal, thereby preventing blood flow therethrough.

[0009] Yet another aspect of the invention relates to aiding advancement of the catheter through the vasculature by directing a fluid jet in a retrograde direction through an orifice in the distal porous cuff section / tip of the catheter.

[0010] Yet another aspect of the present invention relates to reducing the coefficient of friction of the inner surface of the distal porous cuff section / tip of the catheter.

[0011] The present invention is directed to an intravascular catheter including a distal porous cuff section having a plurality of unobstructed openings defined radially outward from an annular inflation chamber, where the distal porous cuff section is non-rotatable. The catheter also includes a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section and having an inner lumen defined axially therethrough. The tubular body sidewall has an inflation supply channel extending in a direction parallel to the axial direction of the intravascular catheter.

[0012] Additionally, the present invention also relates to a method for using an intravascular catheter having a proximal end and an opposing distal end, the intravascular catheter including a distal porous cuff section having a plurality of unobstructed openings defined radially outward from an annular inflation chamber, where the distal porous cuff section is non-rotatable. The intravascular catheter also has a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from the proximal end to the distal porous cuff section and defining an inner lumen axially therethrough. The sidewall of the tubular body has an inflation supply channel extending in a direction parallel to the axial direction of the intravascular catheter. The method of the present invention includes the step of minimizing friction between an outer surface of the intravascular catheter and an inner wall of the blood vessel by injecting pressurized fluid into an inflation supply channel while navigating the intravascular catheter so that the distal end is in proximity to a blood clot within the blood vessel, thereby forming a cuff of fluid jets that are ejected into the blood vessel from a plurality of openings defined in a distal porous cuff section of the tubular body. [Brief description of the drawings]

[0013] These and other features of the present invention will become more readily apparent from the following detailed description and drawings which illustrate the invention and in which like reference numerals refer to like elements throughout the several views. [Figure 1] FIG. 2 is a cross-sectional view of a portion of a blood vessel showing the distal porous cuff section / tip of an intravascular catheter of the present invention positioned adjacent to a target clot. [Diagram 2] FIG. 2 is a side view of the first embodiment of the intravascular catheter of the present invention of FIG. 1, in which the tubular body of the catheter proximal to the distal porous cuff section / tip is constructed as a single wall and has a single axial inflation supply channel defined therein. [Figure 2A] FIG. 3 is a cross-sectional view of the intravascular catheter of FIG. 2 taken along line II(A)-II(A) through the distal porous cuff section / tip. [Figure 2B] FIG. 3 is a cross-sectional view of the intravascular catheter of FIG. 2 taken along line II(B)-II(B) through the distal porous cuff section / proximal tubular body of the tip. [Figure 2C] FIG. 3 is a cross-sectional view through the intravascular catheter of FIG. 2 along line II(C)-II(C), including the distal porous cuff section / tip. [Figure 2D] FIG. 2C is a proximal radial cross-sectional view of a distal porous cuff section / tip similar to that of FIG. 2B, but depicting an alternative configuration of a tubular body of an intravascular catheter of the present invention having a single-walled sidewall with multiple axial inflation supply channels defined therein. [Figure 3A] FIG. 1 is a longitudinal cross-sectional view of the distal porous cuff section / tip of an intravascular catheter of the present invention depicting fluid being expelled radially outward through openings that are in fluid communication with the annular expansion chamber, the openings being positioned non-perpendicular (i.e., at an oblique angle toward the proximal end of the catheter relative to the axial direction of the catheter). [Figure 3B] FIG. 1 is a longitudinal cross-sectional view of the distal porous cuff section / tip of an intravascular catheter of the present invention depicting fluid being expelled radially outward through openings that are in fluid communication with the annular expansion chamber, the openings being positioned non-perpendicular (i.e., at an oblique angle toward the distal end of the catheter relative to the axial direction of the catheter). [Figure 4] FIG. 1 is a longitudinal cross-sectional view of the distal porous cuff section / tip of an intravascular catheter of the present invention illustrating fluid being released both radially outward and radially inward through openings that are in fluid communication with the annular expansion chamber. [Figure 5A] FIG. 2 depicts one configuration of the distal porous cuff section / tip of the intravascular catheter of the present invention in an enlarged / expanded, inflated state. [Figure 5B] FIG. 5B depicts the distal porous cuff portion of the intravascular catheter of the present invention of FIG. 5A in a non-expanded / non-dilated state. [Figure 5C] A cross-sectional view of the distal porous cuff section / proximal tubular body of the tip taken along line V(C)-V(C) in FIG. 5B illustrating a single radial section inflation supply channel defined within a single wall of the tubular body of the intravascular catheter. [Figure 6A] FIG. 13 is a longitudinal cross-sectional view of the distal porous cuff section / tip of another configuration of an intravascular catheter of the present invention in a flared state forming a conical funnel, showing internal connecting ribs disposed within the annular expansion chamber. [Figure 6B] FIG. 6B is a side view of the distal porous cuff section / tip of the intravascular catheter of the present invention of FIG. 6A in a non-flared state. [Figure 7] FIG. 1 is a side view of yet another configuration of the intravascular catheter of the present invention, in which the distal porous cuff section / proximal tubular body of the tip is configured as two concentric walls radially spaced a predetermined distance from each other to define an annular inflation supply channel therebetween. [Figure 7A] FIG. 8 is a cross-sectional view of the intravascular catheter of FIG. 7 taken along line VII(A)-VII(A) through the distal porous cuff section / tip. [Figure 7B] FIG. 8 is a cross-sectional view of the intravascular catheter of FIG. 7 taken along line VII(B)-VII(B) through the distal porous cuff section / proximal tubular body of the tip. [Figure 7C] FIG. 8 is a cross-sectional view of the intravascular catheter of FIG. 7 taken along line VII(C)-VII(C), including the distal porous cuff section / tip of the intravascular catheter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The terms "distal" or "proximal" are used in the following description with reference to a location or direction relative to the treating or interventional physician. "Distal" or "distally" is a location or direction away from the physician or interventional physician. "Proximal" or "proximally" or "proximal" is a location or direction closer to the physician or interventional physician. The terms "obstruction," "clot," or "blockage" are used interchangeably.

[0015] FIG. 1 shows a partial axial cross-section through a blood vessel 102 having a clot, obstruction, thrombus or occlusion 150 lodged therein. An intravascular catheter 100 of the present invention having an inner central lumen 105 defined therein is advanced axially from its proximal end to its opposite distal end until it is in close proximity to the clot 150. The distal and proximal ends of the inner central lumen 105 are open and sized to accommodate the trapped clot therethrough during removal. Ancillary devices, such as guidewires, delivery wires, mechanical thrombectomy devices, containment catheters, etc., may be advanced distally through the inner central lumen 105. A biocompatible fluid, preferably saline, may be infused under pressure only through one or more inflation supply channels defined within the tubular body of the catheter and positioned radially outward of the inner central lumen 105.

[0016] FIG. 2 shows a side view of the distal portion of a first embodiment of an intravascular catheter of the present invention, including the distal porous cuff section / tip 127 and the tubular body (i.e., the remainder of the intravascular catheter disposed proximal to the distal porous cuff section / tip). In this first embodiment, the sidewall 115 of the tubular body is constructed as a single wall, including either a single layer or a laminate / composite of multiple layers (e.g., a liner, a braid, a polymer jacket and / or a coating). When formed or defined (e.g., molded) in the single wall sidewall 115, a single inflation supply channel 120 extends parallel to the axial direction of the catheter. FIG. 2B shows a cross-sectional view along line II(B)-II(B) of FIG. 2 through the tubular body proximal to the distal porous cuff section / tip 127 of the catheter. While only a single axial inflation channel 120 is shown in the single wall sidewall in FIG. 2B, FIG. 2D shows an alternative design of the single wall sidewall 115 of the catheter tubular body having three axial inflation supply channels 120 defined therein, each axial inflation channel being radially spaced apart from one another by an equal distance. Any number of one or more axial inflation supply channels 120, as well as the diameter and arrangement of such axial inflation supply channels within the single wall sidewall of the catheter tubular body, may be modified as desired. It is further contemplated that radial sections of inflation supply channels may be formed within the single wall of the tubular body of the intravascular catheter of the present invention, as seen in FIG. 5C. Two wall tubular body configurations are also possible, as shown in FIGS. 7-7D and described in more detail below, in which the inflation supply channels are defined by the space between the two walls of the two wall catheter.

[0017] The distal section of the intravascular catheter 100 functions as a fixed (non-rotating relative to the remaining proximal tubular body) distal porous cuff section / tip 127 having an annular inflation chamber 122 in fluid communication with one or more inflation supply channel(s) 120 (axial or radial). As clearly shown in FIG. 2A, a plurality of openings 125 are defined within the distal porous cuff section / tip 127 and disposed radially outward from the annular inflation chamber 122. Preferably, the openings 125 are disposed 360 degrees within the distal porous cuff section / tip 127. The exemplary axial cross-sectional view of FIG. 2C illustrates the annular inflation chamber 122 of the distal porous cuff section / tip 127 in fluid communication with the single axial inflation supply channel 120 of the tubular body, as well as the plurality of openings 125 defined radially outward and in fluid communication with the annular inflation chamber 122. When dispensed under pressure through one or more axial inflation delivery channel(s) 120, the biocompatible fluid (e.g., saline) emerging from the openings 125 defined in the distal porous cuff section / tip 127 forms a fluid jet "cuff," "cloud," "pillow," or "pool" around the outer periphery of the distal section of the catheter to minimize friction with the vessel wall, minimize damage to the surrounding tissue, aid in navigation, and allow the distal end or tip of the catheter to advance in close proximity to the clot surface. The fluid jet "cuff" formed from the inflation fluid is injected with sufficient pressure to form a fluid interface between the outer surface of the catheter and the inner wall of the vessel, minimizing friction between them without crushing or disrupting the clot. The placement of the openings 125 in the distal porous cuff section / tip 127 of the catheter ensures that the clot is not crushed or disrupted by the fluid jet. The distal porous cuff section / tip 127 remains stationary, fixed, or non-rotating relative to the tubular body of the catheter while draining fluid from openings 125. The radial openings 125 in the distal porous cuff section / tip 127 of the catheter function only as drainage ports for the passage of fluid from the catheter. Fluids and / or substances are never introduced into the interior of the catheter from the exterior of the catheter through the radial openings 125.In other words, once the fluid is released through radial opening 125, it does not then circulate back through a radial opening (either the same radial opening or any other radial opening along the side of the catheter). Furthermore, all radial openings along the side of the catheter remain unobstructed and do not have any covering extending over the openings on the outside.

[0018] In an alternative configuration shown in Figure 7, the proximal tubular body of the distal porous cuff section / tip of the catheter of the present invention may have a two-wall sidewall structure rather than the single wall structure depicted in Figure 2. Figures 7A and 7B show the two-wall catheter structure of Figure 7 along lines VII(A)-VII(A) (through the distal porous cuff section / tip) and VII(B)-VII(B) (through the proximal tubular body of the distal porous cuff section / tip), respectively. The two-wall sidewall structure of the proximal tubular body of the distal porous cuff section / tip 127 is shown in Figure 7B and includes an inner wall 113 disposed radially inward of an outer wall 114 spaced apart from each other by a predetermined distance to form an annular, radial, circular, ring-shaped, or circumferential inflation supply channel 120' therebetween. Inner wall 113 and outer wall 114 are preferably concentric, but may otherwise be eccentrically disposed, as shown in Figure 7B. Again, a plurality of openings 125 are defined radially outward from annular inflation chamber 122 in distal porous cuff section / tip 127 (Figure 7A).

[0019] In the case of a two-walled tubular body structure of an intravascular catheter of the present invention (as shown in FIG. 7B) that forms an annular inflation supply channel 120' between the walls, the introduced fluid is substantially equally distributed from the distal porous cuff section / tip opening 125 as a fluid jet. In the case of one or more axial inflation channel(s) 120 (FIG. 2B or FIG. 2D) that are formed in a single wall of the catheter's tubular body, the introduced fluid is unevenly distributed from the distal porous cuff section / tip opening 125. That is, the fluid may be distributed at a faster rate from the opening 125 closest to the proximal end of the catheter relative to the opening 125 closest to the opposite distal end of the catheter. The diameter of the openings 125 may be varied to substantially uniform the distribution of fluid from such openings 125.

[0020] With reference to FIG. 2C, the openings 125 defined radially outwardly in the distal porous cuff section / tip 127 may be disposed perpendicular to the axial direction of the catheter. These openings 125 of the distal porous cuff section / tip may alternatively be disposed at a non-perpendicular angle (i.e., at an oblique angle). In the exemplary axial cross-section through the distal porous cuff section / tip shown in FIG. 3A, the openings 125 in the distal porous cuff section / tip are defined radially outwardly non-perpendicularly (i.e., at an oblique angle pointing proximally toward the proximal end of the catheter), such that the fluid jet formed pushes / advances the catheter distally forward to assist in maneuvering the catheter through the blood vessel to a desired location. Yet another non-perpendicular (i.e., at an oblique angle pointing distally toward the distal end of the catheter) arrangement of the openings 125 defined radially outwardly in the distal porous cuff section / tip is shown in FIG. 3B. Positioning the openings toward the distal side (FIG. 3B) provides additional fluid to the space between the catheter and the clot, thereby forming a "pool" or "cloud" of fluid that surrounds the clot and flows into the catheter tip under suction. This fluid can also serve to reduce friction between the clot and the catheter. Furthermore, the openings do not have to all coincide in that some may be positioned perpendicularly while others may be positioned non-perpendicularly to the axial direction of the catheter (i.e., at an oblique angle facing proximally and / or distally).

[0021] In FIG. 2C, openings 125 are only defined radially outward from the annular inflation chamber 122 in the distal porous cuff section / tip 127 to aid in advancing the catheter through the blood vessel to the target site. It is further contemplated that openings 125 may also be defined radially inward from the annular inflation chamber 122 in the distal porous cuff section / tip 127 to aid in drawing trapped clots into the catheter or to aid in retrieving them during aspiration. FIG. 4 depicts a distal porous cuff section / tip in which vertically disposed openings 125 are defined both radially inward and radially outward from the annular inflation chamber 122. Thus, openings 125 may be defined radially inward and / or radially outward from the annular inflation chamber 122 in the distal porous cuff section / tip 127 with any desired arrangement of such openings (e.g., vertical, non-vertical / angled). The angle of arrangement need not be the same between openings.

[0022] As an alternative to the use of a separate conventional inflatable balloon component that is bonded, connected, attached, or welded to the outer surface of the catheter to block blood flow, the annular inflation chamber 122 of the distal porous cuff section / tip 127 of the intravascular catheter of the present invention can accomplish this goal without blocking, isolating, or covering any of the radial openings 125. Specifically, if the pressure and / or volume of fluid introduced into the annular inflation chamber 122 exceeds the rate at which it can be dispensed through the radial openings 125, the pressure and volume of fluid introduced into the annular inflation chamber 122 will increase / grow, changing the outer contour of the distal porous cuff section / tip 127 (i.e., to a hyper-inflated state). In one configuration shown in Figures 5A-5D, the outer wall of the distal porous cuff section / tip 127 is made from a compatible material. Apart from being at the distal end of the annular expansion chamber 122, the inner and outer radial walls, separated from each other by a predetermined distance within the annular expansion chamber 122, are not fixed, joined or tethered in any manner (i.e., the annular expansion chamber does not have any internal connecting ribs). Thus, as the pressure and volume of fluid injected / introduced into the annular expansion chamber 122 increases / increases, the compliant outer wall bulges radially outward. If sufficient pressure increases / increases within the annular expansion chamber 122, the expanded or enlarged diameter of the outer wall of the distal porous cuff section will physically contact and seal against the inner wall of the blood vessel, preventing blood flow therethrough. Because the annular expansion chamber 122 does not have any internal connecting ribs, inflation with highly pressurized fluid creates a radially outward bulging profile of the outer wall of the distal porous cuff section / tip 127 relative to the profile of the inner wall (similar to an inflated balloon).

[0023] Instead of bulging the outer contour, the distal porous cuff section / tip 127 may be configured such that when the distal porous cuff section / tip is subjected to an infusion of fluid into the annular inflation chamber 122 at a pressure and volume that exceeds what the distal porous cuff section / tip can dispense through the opening 125, the distal porous cuff section / tip flares outward to form a conical funnel shape. An axial cross-sectional view of the distal cuff section / tip of the catheter in an expanded / expanded state having a flared conical funnel shape is shown in FIG. 6A and its unexpanded / unexpanded state is shown in FIG. 6B. The maximum diameter of the flared conical funnel shaped distal porous cuff section / tip occupies its most distal end, and the opposite proximal end has a diameter substantially equal to that of the remaining tubular body of the catheter proximal to the distal porous cuff section / tip. In the non-flared state, the diameter (both inner and outer diameters) of the distal porous cuff section / tip is substantially equal to the diameter (both inner and outer diameters) of the remaining tubular body portion of the catheter proximal to the distal porous cuff section / tip. The widening of the distal porous cuff section / tip into a conical funnel shape is achieved by having a number of connecting ribs 130 (similar to those of an airbed) disposed within the annular inflation chamber 122 itself. As a result of the internal connecting ribs 130, as the volume and pressure of the fluid within the annular inflation chamber 122 increases, the distal porous cuff section / tip 127 widens into a conical funnel shape while the inner and outer walls remain substantially equidistant to each other (rather than the outer wall expanding like a balloon). Advantageously, such an alternative conical funnel shape configuration serves two purposes: to occlude blood flow and the enlarged diameter of the distal end optimizes complete collection of blood clots into the catheter.

[0024] Instead of requiring the application of suction or negative pressure to deflate, as is required with conventional balloons sealed to the exterior surface of the catheter, the bulging or flared conical funnel created by the introduction of highly pressurized fluid into the annular inflation chamber of the distal porous cuff section / tip of the intravascular catheter of the present invention advantageously deflates itself automatically. Thus, the need for the application of suction or negative pressure to deflate the outer contour of the distal porous cuff section / tip is eliminated. That is, cessation of fluid injection or reduction in pressure into the annular inflation chamber 122 results in the natural automatic self-deflation of the pressurized fluid therein through the opening 125 and a contraction / reduction in the diameter of the outer contour of the distal porous cuff section / tip until an equilibrium pressure is achieved outside the catheter and within the annular inflation chamber 122.

[0025] During operation, a biocompatible fluid, preferably saline, is injected under positive pressure through one or more inflation channels 120, 120' defined in the sidewall of the tubular body of the intravascular catheter of the present invention to aid in maneuverability while the intravascular catheter is advanced through the blood vessel to a site proximate to the target clot. The pressurized fluid enters the annular inflation chamber 122 and is expelled (as a fluid jet) from the annular inflation chamber 122 in the distal porous cuff section / tip 127 through a plurality of openings 125 defined radially outward and / or radially inward. The fluid jet "cuff", "cloud" or "pillow" formed from the openings in the distal porous cuff section / tip of the intravascular catheter of the present invention minimizes friction and reduces the risk of irritation or trauma to the surrounding tissue. The low friction "cuff", "cloud" or "pillow" allows the "cloud" or "pillow" formed by the fluid jet to be manipulated to bring the distal end of the intravascular catheter closer to the face or surface of the clot. When an opening is defined radially inward from the annular inflation chamber 122 in the distal porous cuff section / tip, then a fluid jet formed therefrom within the inner central lumen 105 assists in complete collection of the blood clot into the catheter.

[0026] Once the distal end of the catheter is positioned proximal to the clot, a vacuum (e.g., negative pressure) can be applied to the inner central lumen 105 to retrieve the clot into the catheter by suction. To optimize full and complete ingestion of the clot, the diameter of the distal end of the catheter is preferably larger than the diameter of the clot. However, an expanded or enlarged diameter is undesirable during navigation of a tortuous path. Thus, the intravascular catheter of the present invention has a distal porous cuff section / tip of normal (unexpanded / non-expanded) outer diameter size when advanced to a target site within the blood vessel proximal to the clot. Once properly positioned, the same inflation channel used to introduce biocompatible fluid under pressure can be used to transition the outer contour of the distal porous cuff section of the catheter from a first state having a non-expanded / non-expanded diameter to a second state having an enlarged / expanded diameter to facilitate containment of the clot therein, thereby optimizing complete ingestion of the clot. An additional advantage of blocking blood flow within a blood vessel may be realized if, while in the expanded / expanded state, a portion of the outer surface of the distal porous cuff section comes into physical contact with the inner wall of the blood vessel and forms a seal therebetween.

[0027] The fluid jet "cuff", "cloud" or "pillow" formed around the distal porous cuff section / tip of the intravascular catheter of the present invention reduces the surface friction of the inner wall of the blood vessel during delivery of the catheter to the target site. Thus, the intravascular catheter of the present invention can eliminate the need for a low-friction lubricious coating applied to the outer surface of the catheter in some applications. However, it is contemplated within the present invention for the catheter of the present invention to use a low-friction coating as well.

[0028] Although the basic novel features of the present invention as applied to the preferred embodiment thereof have been shown, described, and pointed out, those skilled in the art will appreciate that various omissions, substitutions, and changes in the form and details of the illustrated systems / apparatuses, and in their operation, may be made without departing from the spirit and scope of the present invention. For example, all combinations of elements and / or steps that perform substantially the same functions in substantially the same manner to achieve the same results are expressly intended to be encompassed within the scope of the present invention. Also, the substitution of elements from one embodiment described above for another embodiment is fully intended and anticipated. It should also be understood that the drawings are not necessarily drawn to scale, and are merely conceptual. It is therefore intended to be limited only by the scope of the appended claims.

[0029] All issued patents, pending patent applications, publications, articles, books, or other references cited herein are each hereby incorporated by reference in their entirety.

[0030] [Embodiment] (1) An intravascular catheter having a proximal end and an opposite distal end, the intravascular catheter comprising: a distal porous cuff section having a plurality of unobstructed openings defined radially outward from the annular inflation chamber, the distal porous cuff section being non-rotatable; an inflation supply channel extending in a direction parallel to an axial direction of the catheter; and a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section and having an inner lumen defined axially therethrough, the sidewall of the tubular body having an inflation supply channel extending in a direction parallel to an axial direction of the catheter. (2) An intravascular catheter as described in embodiment 1, wherein the side wall of the tubular body is a single wall comprising a single layer or a laminate of multiple layers, and the inflation supply channel is molded into the single wall. (3) An intravascular catheter as described in embodiment 1, wherein the side wall includes two walls, including an inner wall and an outer wall, and the inflation supply channel is an annular inflation supply channel defined between the two walls radially separated from each other by a predetermined distance. (4) An intravascular catheter as described in embodiment 1, wherein at least a portion of the plurality of openings in the distal porous cuff section are arranged perpendicular to the axial direction of the intravascular catheter. (5) The intravascular catheter of embodiment 1, wherein at least a portion of the plurality of openings in the distal porous cuff section are disposed at a non-perpendicular angle relative to an axial direction of the intravascular catheter, the non-perpendicular angle being an angle inclined toward the proximal end of the intravascular catheter or an angle inclined toward the distal end of the intravascular catheter.

[0031] (6) An intravascular catheter as described in embodiment 1, wherein the distal porous cuff section has a plurality of openings defined radially inwardly therein that are in fluid communication between the annular inflation chamber and the inner lumen. (7) An intravascular catheter as described in embodiment 1, wherein the annular expansion chamber does not have internal connecting ribs and, in a super-inflated state, at least a portion of the outer surface of the distal porous cuff section is expandable radially outward. (8) The intravascular catheter of embodiment 1, wherein the annular expansion chamber has a plurality of internal connecting ribs, and in a hyper-inflated state, the distal cuff section flares to form a conical funnel. (9) An intravascular catheter as described in embodiment 1, wherein the multiple openings remain uncovered on the outside. (10) A method for using an intravascular catheter having a proximal end and an opposite distal end, the intravascular catheter including: a distal porous cuff section having a plurality of unobstructed openings defined radially outward from an annular inflation chamber, the distal porous cuff section being non-rotatable; and a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section and defining an inner lumen axially therethrough, the sidewall of the tubular body having an inflation delivery channel extending in a direction parallel to an axial direction of the intravascular catheter, the method comprising: while navigating the intravascular catheter so that the distal end is in proximity to a clot within the blood vessel, injecting a pressurized fluid into the inflation supply channel to form a cuff of fluid jets that eject into the blood vessel from the plurality of openings defined in the distal porous cuff section of the tubular body, thereby minimizing friction between an outer surface of the intravascular catheter and an inner wall of the blood vessel.

[0032] (11) further comprising the step of increasing the pressure of the fluid injected into the annular expansion chamber such that, once the distal end of the intravascular catheter is positioned proximate to the clot, at least a portion of an outer surface of the distal porous cuff section expands radially outward; 11. The method of embodiment 10, wherein at least a portion of the enlarged outer surface of the distal porous cuff section physically contacts the inner wall of the blood vessel and obstructs blood flow therethrough. (12) The method of embodiment 11, wherein the annular expansion chamber does not have internal connecting ribs, and further comprising the step of introducing sufficient fluid into the annular expansion chamber to transition the enlarged portion of the outer surface of the distal porous cuff section to a hyper-inflated state in which the enlarged portion bulges radially outward. 13. The method of claim 11, wherein the annular inflation chamber has a plurality of internal connecting ribs, and further comprising the step of introducing sufficient fluid into the annular inflation chamber such that the enlarged portion of the distal porous cuff section forms a flared conical funnel. 14. The method of claim 10, wherein the sidewall of the tubular body is a unitary wall comprising a single layer or a stack of multiple layers, and the inflation feed channel is molded into the unitary wall. (15) The method of claim 10, wherein the side wall includes two walls including an inner wall and an outer wall, and the expansion supply channel is an annular expansion supply channel defined between the two walls radially spaced a predetermined distance from each other.

[0033] (16) The method of embodiment 10, wherein at least a portion of the plurality of openings in the distal porous cuff section are arranged perpendicular to an axial direction of the intravascular catheter. (17) The method of embodiment 10, wherein at least a portion of the plurality of openings in the distal porous cuff section are disposed at a non-perpendicular angle relative to an axial direction of the intravascular catheter, the non-perpendicular angle being an angle oblique toward the proximal end of the intravascular catheter or an angle oblique toward the distal end of the intravascular catheter. (18) The method of embodiment 10, wherein the distal porous cuff section has a plurality of openings defined radially inwardly therein that are in fluid communication between the annular inflation chamber and the inner lumen. 19. The method of claim 10, wherein the plurality of openings are left uncovered on the outside. (20) The method of embodiment 10, wherein the cuff of fluid jet ejected from the plurality of openings provides lubrication between the distal end of the intravascular catheter and the inner wall of the blood vessel.

[0034] 21. The method of claim 20, wherein the cuff of fluid jets ejected from the plurality of openings eliminates the need for a lubricious coating.

Claims

1. 1. An intravascular catheter having a proximal end and an opposed distal end, the intravascular catheter comprising: a distal porous cuff section having a plurality of unobstructed openings defined radially outward from the annular inflation chamber, the distal porous cuff section being non-rotatable; a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section and having an inner lumen defined axially therethrough, the sidewall of the tubular body having an inflation supply channel extending in a direction parallel to an axial direction of the intravascular catheter; an annular inflation chamber for inflating a distal portion of the inner lumen through the distal cuff section and a distal porous cuff section having a plurality of second openings defined radially inwardly therethrough that are in fluid communication between the annular inflation chamber and the inner lumen;

2. The intravascular catheter of claim 1 , wherein the sidewall of the tubular body is a unitary wall comprising a single layer or a laminate of multiple layers, and the inflation delivery channel is molded into the single wall.

3. 2. The intravascular catheter of claim 1, wherein the side wall includes two walls, including an inner wall and an outer wall, and the inflation supply channel is an annular inflation supply channel defined between the two walls radially spaced a predetermined distance from each other.

4. The intravascular catheter of claim 1 , wherein at least a portion of the plurality of unobstructed openings in the distal porous cuff section are disposed perpendicular to an axial direction of the intravascular catheter.

5. 2. The intravascular catheter of claim 1, wherein at least a portion of the plurality of unobstructed openings in the distal porous cuff section are disposed at a non-perpendicular angle relative to an axial direction of the intravascular catheter, the non-perpendicular angle being an angle oblique toward the proximal end of the intravascular catheter or an angle oblique toward the distal end of the intravascular catheter.

6. 10. The intravascular catheter of claim 1, wherein the annular expansion chamber has no internal connecting ribs and, in a hyper-inflated state, at least a portion of an outer surface of the distal porous cuff section is expandable radially outward.

7. An intravascular catheter having a proximal end and an opposite distal end, the intravascular catheter comprising: a distal porous cuff section having a plurality of unobstructed openings defined radially outward from the annular inflation chamber, the distal porous cuff section being non-rotatable; a tubular body disposed proximal to the distal porous cuff section, the tubular body having a sidewall extending from a proximal end to the distal porous cuff section and having an inner lumen defined axially therethrough, the sidewall of the tubular body having an inflation supply channel extending in a direction parallel to an axial direction of the intravascular catheter; An intravascular catheter, wherein the annular expansion chamber has a plurality of interconnecting ribs, and in a hyper-inflated state, the distal porous cuff section flares to form a conical funnel.

8. The intravascular catheter of claim 1 , wherein the plurality of unobstructed openings remain externally uncovered.

Images