Patent Description:
This disclosure is related generally to a catheter assembly, and more particularly to a catheter assembly having an expandable perforation treatment device permitting perfusion past the perforation treatment device.

During percutaneous coronary intervention (PCI), it is possible for a vessel (coronary artery) to become perforated/dissected. For example, a guidewire may be accidentally pushed out of the vessel or a stent may become over expanded, causing a perforation in the vessel. A perforated vessel may lead to complications such as rapid blood loss or buildup of fluid around the tissue adjacent the vessel. A conventional method of treating a perforated vessel is to cover the perforation with an inflated balloon for a period of time (e.g., <NUM> hour) to allow for sufficient clotting to occur, blocking the perforation. In use, the balloon is delivered to a treatment location by inserting the balloon in an uninflated configuration through a body lumen (e.g., a blood vessel/vasculature). Balloons can be inserted through a body lumen by tracking the uninflated balloon through an introducer sheath and/or along a guidewire. Once the uninflated balloon has reached the treatment location, fluid is delivered into the balloon, thereby expanding the outer circumference of the balloon (i.e., the balloon is inflated). The expansion of the balloon completely occludes the body lumen preventing fluid flow past the balloon. However, when the perforation occurs in a major vessel in a proximal location (e.g., proximal RCA or proximal LAD), this process is less desirable as the balloon blocks blood flow to the downstream myocardium for the time that it is inflated.

<CIT> describes a system and method for low-profile occlusion balloon catheter. <CIT> describes a scaffold for tubular septal occluder device and techniques for attachment.

<CIT> describes vascular treatment devices.

<CIT> describes an intravascular hemostasis-type catheter.

<CIT> describes a system and method for delivering a catheter.

<CIT> describes systems and methods for acute treatment to limit intracerebral hemorrhage growth.

<CIT> describes a system for endoscopic surgery within a body lumen of a patient including a flexible catheter having an expandable region at a distal portion and an access opening.

<CIT> describes a catheter having a tapered structure and a balloon formed above a lower drainage hole.

<CIT> describes a system and method for low profile occlusion balloon catheter. In one embodiment of <CIT>, the inclusion of the restraining filament preferably creates a reverse curvature in the balloon and permits fluid to flow past the balloon through a blood flow channel or multiple blood flow channels.

<CIT> describes balloon-manipulating devices, balloon catheter assemblies, and methods thereof.

An aspect of the present disclosure provides a catheter assembly including a catheter tube and an expandable unit attached to a distal end portion of the catheter tube. The catheter tube is sized and shaped for delivery through a body lumen of a subject. The expandable unit is configurable in a first configuration and a second configuration. The first configuration is a collapsed configuration for facilitating delivery of the catheter assembly through the body lumen. The second configuration is a fully expanded configuration for contacting an interior wall of the body lumen to cover a perforation in the body lumen. The expandable unit defines at least one longitudinal channel extending from a proximal end of the expandable unit to a distal end of the expandable unit when the expandable unit is in the fully expanded configuration to permit blood flow past the expandable unit.

An example (not claimed) of the present disclosure provides a method of treating a perforation in a body lumen of a subject. The method includes steps of delivering a catheter assembly to a perforation site in the body lumen, expanding an expandable unit of the catheter assembly to contact an interior wall of the body lumen to cover a perforation in the body lumen, and permitting blood flow past the expandable unit while the expandable unit is in contact with the interior wall of the body lumen covering the perforation.

Referring to <FIG> and <FIG>, one embodiment of a balloon catheter (broadly, a catheter assembly) is generally indicated at reference number <NUM>. In general, the balloon catheter <NUM> comprises a medical balloon assembly, generally indicated at <NUM>, and an inflation conduit assembly, generally indicated at <NUM>. The inflation conduit assembly <NUM> comprises a catheter tube <NUM>, defining an inflation lumen (not shown) fluidly coupled to the balloon assembly <NUM> to deliver inflation fluid through the inflation lumen to an interior of the balloon assembly, and a guidewire lumen <NUM> configured to provide a passage for a guidewire (not shown) to facilitate delivery of the balloon catheter <NUM> through a patient's vasculature (broadly, a body lumen). The balloon assembly <NUM> comprises at least one balloon <NUM> (broadly, an expandable unit). The balloon assembly <NUM> may include an additional number of balloons without departing from the scope of the disclosure. Each balloon <NUM> may comprise one or more layers each having the same or different properties and constructions. The balloons <NUM> may be formed by any suitable manner such as from parisons or extrusion. The balloon catheter <NUM> further comprises a pair of blocking portions <NUM> (only one is shown) extending over the balloon <NUM> limiting expansion of the balloon when the balloon is fully inflated. As will be explained in greater detail below, the blocking portions <NUM> create perfusion channels <NUM> that allow passage of fluid (e.g., blood) past the balloon <NUM> when the balloon is fully inflated.

In the illustrated embodiment, the balloon catheter <NUM> comprises a fully assembled balloon catheter that includes the medical balloon assembly <NUM>, among other components. For example, the balloon catheter <NUM> may also comprise a stent (not shown) received around the deflated balloon assembly <NUM>. It will be understood that a medical balloon assembly can comprise a subassembly of the balloon catheter. For example, in one or more embodiment, a balloon catheter <NUM> comprises the medical balloon assembly <NUM> in a subassembly separate from the inflation conduit <NUM>.

In the illustrated embodiment, the balloon <NUM> comprises a single piece of monolithic material. For example, in one or more embodiment, the balloon <NUM> is formed from a bondable material, such as one of a PEBA and a nylon (e.g., one of PEBAX® elastomer and nylon <NUM>). The balloon <NUM> can also have other configurations. For example, in one or more embodiment, one or more of the balloons of the balloon assembly can comprise a multi-layer balloon (e.g., co-extruded, multilayer balloon) or have other arrangements of sections of discrete materials. In certain embodiments, when the balloons are formed from multiple materials, portions (e.g., layers) of the balloon that contacts the inflation conduit are formed from bondable materials such that the components of the medical balloon assembly can be secured by direct bonds.

A length of the balloon <NUM> extends along an axis of the balloon catheter from a proximal end to a distal end thereof, and an inflatable portion <NUM> of the balloon extends along the length of the balloon assembly between the proximal and distal end. When inflation fluid is delivered to the interior of the balloon <NUM> through the inflation conduit assembly <NUM>, the inflatable portion <NUM> is configured to radially expand from an uninflated configuration (<FIG>) to an inflated configuration (<FIG>). Thus, the inflatable portion <NUM> defines an interior space of the balloon <NUM> when the balloon is inflated. The blocking portions <NUM> of the catheter tube <NUM> prevent expansion of the balloon <NUM> along longitudinal segments of the balloon. Therefore, the inflatable portion <NUM> does not extend circumferentially around an entirety of the balloon <NUM> at any longitudinal point along the length of the balloon. This discontinuity in the inflation portion <NUM> is what forms the perfusion channels <NUM>. In one or more embodiment, the balloon <NUM> can be one of non-compliant, semi-compliant, and compliant in the inflated configuration. In the illustrated embodiment, the inflatable portion <NUM> of the balloon <NUM> comprises a pair of lobed inflated sections diametrically opposed to each other. In one or more embodiment, the balloon <NUM> has other shapes in the inflated configuration.

The catheter tube <NUM> has a proximal end portion configured for connection to an inflation fitting, a distal end portion secured to the balloon assembly <NUM>, and a length extending along an axis of the catheter tube from the proximal end portion to the distal end portion. Thus, the inflation lumen in the catheter tube <NUM> is connectable to a source of inflation fluid (not shown) for inflating the balloon <NUM>. In one or more embodiment, the inflation lumen is concentrically disposed around the guidewire lumen <NUM> and extends from the proximal end portion to the distal end portion to provide fluid communication between the source of inflation fluid and the interior of the balloon assembly <NUM>. The illustrated catheter tube <NUM> comprises a single tube. In other embodiments, the catheter tube <NUM> can have other configurations (e.g., multiple tubes). Further, the catheter tube <NUM> may be formed by any suitable manner. In one embodiment, the catheter tube <NUM> is an extruded polymer tube.

Referring to <FIG>, at least one blocking portion <NUM> extends along the distal portion of the catheter tube <NUM> covering a section of the balloon <NUM>. The blocking portion <NUM> extends along the entire length of the balloon <NUM>. In the illustrated embodiment, two diametrically opposed blocking portions <NUM> (only one is shown) are disposed over the balloon <NUM>. However, more than two blocking portions <NUM> and/or blocking portions arranged in other locations on the balloon <NUM> may be incorporated without departing from the scope of the disclosure. Additionally, in the illustrated embodiment, each blocking portion <NUM> comprises an elongate rectangular segment. However, the blocking portions <NUM> could have other shapes without departing from the scope of the disclosure. The blocking portions <NUM> comprise a material that is stiffer than the material of the balloon <NUM> such that it will not expand in the same manner as the balloon material when the balloon is inflated. In one embodiment, the blocking portions <NUM> comprise a material having a stiffness that substantially resists expansion when the balloon <NUM> is inflated. In embodiments not forming part of the claimed invention, the blocking portions <NUM> may be extruded sections that are separately attached to the catheter tube <NUM>. The blocking portions <NUM> may be formed from the same material as the catheter tube <NUM>, or in embodiments not forming part of the claimed invention, the blocking portions may be formed from a different material. As such, the blocking portions <NUM> may have the same stiffness as the catheter tube <NUM>, or the blocking portions may have a stiffness that is different (e.g., stiffer) than the catheter tube. In one embodiment, the blocking portions <NUM> are made from Pebax. For example, the blocking portions <NUM> may be made from a Pebax that is stiffer than Pebax <NUM>. However, the blocking portions <NUM> can be made from other stiff polymer materials without departing from the scope of the disclosure. Additionally, other materials and components could be used for the blocking portions <NUM>. For instance, metals or a combination of metals and polymers could be used. In one embodiment, a spine component is disposed over the balloon <NUM> in the area of the blocking portions <NUM> to perform the blocking function. Still other structures and materials are envisioned.

Referring to <FIG>, the balloon catheter <NUM> is formed by first extruding the catheter tube <NUM> and bonding the balloon <NUM> to an exterior surface <NUM> of the catheter tube along a distal segment of the catheter tube. In one embodiment, the balloon <NUM> is thermally fused to the exterior surface <NUM> of the catheter tube <NUM> at each end of the balloon. However, the balloon could be bonded to the catheter tube <NUM> by other means. It will be understood that the balloon <NUM> may be in the form of a sleeve that is slid over the catheter tube <NUM> to locate the balloon in place for bonding to the catheter tube. Referring to <FIG>, the blocking portions <NUM> may then be fused to an outer surface of the balloon <NUM> along an entire length of the blocking portions. Ends of the blocking portions <NUM> may also be fused to the catheter tube <NUM> to bond the blocking portions <NUM> to the catheter tube. As such, the stiffer material of the blocking portions <NUM> will extend along the entire length of the balloon <NUM> thus forming the perfusion channels <NUM> (<FIG> and <FIG>) that extend along the entire length of the balloon when the balloon is inflated. Therefore, during use of the balloon catheter <NUM>, such as to cover a perforation in a patient's vessel, the balloon <NUM> can be fully inflated to cause the balloon material to contact an interior surface of the vessel around the perforation thereby covering the perforation. However, the blocking portions <NUM> will limit the expansion of at least some of the balloon material that is not used to cover the perforation creating the perfusion channels <NUM> allowing for blood flow past the balloon <NUM>. So the use of the catheter <NUM> to treat the perforation will not meaningfully affect blood flow through the vessel. Accordingly, the organs in communication with the vessel and that are downstream from the perforation will continue to receive the necessary blood flow during the perforation treatment.

Referring to <FIG>, an embodiment according to the claimed invention of a balloon catheter (broadly, a catheter assembly) is generally indicated at <NUM>. The balloon catheter <NUM> may comprise an inflation conduit <NUM> including a catheter tube <NUM>, defining a guidewire lumen <NUM>, and a balloon <NUM> (broadly, an expandable unit) bonded to a distal end portion of the catheter tube. Blocking portions <NUM> are formed integrally with the catheter tube <NUM> and extend along an entire length of the balloon <NUM>.

Referring to <FIG>, the balloon catheter <NUM> is formed by first extruding the catheter tube <NUM>. The extruded catheter tube <NUM> initially has a uniform cylindrical configuration along the distal end portion of the catheter tube. The catheter tube <NUM> is then skived along the distal end portion of the tube at two diametrically opposed locations forming two diametrically opposed openings <NUM> (only one is shown) in the distal end portion of the tube. In the illustrated embodiment, each skive <NUM> comprises a shallow U-shaped cut in the catheter tube <NUM>. However, the skive cuts may have a different shape without departing from the scope of the disclosure. Material of the balloon <NUM> is then bonded to the skived areas <NUM> of the catheter tube <NUM> replacing the catheter material that was cut out with the balloon material. In one embodiment, a laser is used to fuse the balloon <NUM> to the catheter tube <NUM>. Thus, the uniform cylindrical configuration of the distal end portion of the catheter tube <NUM> is restored through a combination of the catheter tube material and the balloon material fused to the catheter tube. The portions of the catheter tube <NUM> between the skived sections <NUM> define the blocking portions <NUM>. The balloon catheter <NUM> is otherwise constructed and functions substantially the same as balloon catheter <NUM> of the previous embodiment.

Referring to <FIG>, another embodiment according to the claimed invention of a balloon catheter (broadly, a catheter assembly) is generally indicated at <NUM>. The balloon catheter <NUM> may comprise an inflation conduit <NUM>, including a catheter tube <NUM> defining a guidewire lumen <NUM>, and a balloon <NUM> (broadly, an expandable unit) bonded to a distal end portion of the catheter tube. Blocking portions <NUM> are formed integrally with the catheter tube <NUM> and extend along an entire length of the balloon <NUM>.

Referring to <FIG>, the balloon catheter <NUM> is formed by first extruding the catheter tube <NUM>. The extruded catheter tube <NUM> initially has a uniform cylindrical configuration along the distal end portion of the catheter tube. The catheter tube <NUM> is then skived along the distal end portion of the tube at two diametrically opposed locations forming two diametrically opposed openings <NUM> (only one is shown) in the distal end portion of the tube. In the illustrated embodiment, each skive <NUM> comprises a shallow U-shaped cut in the catheter tube <NUM>. However, the skive cuts may have a different shape without departing from the scope of the disclosure. Referring to <FIG>, the balloon <NUM> is then bonded to an exterior surface of the catheter tube <NUM> along the distal end portion of the catheter tube and over the openings <NUM>. In one embodiment, the balloon <NUM> is thermally fused to the exterior surface of the catheter tube <NUM>. However, the balloon <NUM> could be bonded to the catheter tube <NUM> by other means. It will be understood that the balloon <NUM> may be in the form of a sleeve that is slid over the catheter tube <NUM> to locate the balloon in place for bonding to the catheter tube. Referring to <FIG>, thermally bonding the balloon <NUM> to the catheter tube <NUM> will cause the balloon material to cover the openings <NUM> in the catheter tube. The balloon material will also overlay the sections of the catheter tube <NUM> between the openings <NUM>. These portions of the balloon material will fuse to the catheter tube <NUM>, preventing expansion of the balloon material in these areas, thereby forming the blocking portions <NUM>. The balloon catheter <NUM> is otherwise constructed and functions substantially the same as balloon catheter <NUM> of the previous embodiment.

Referring to <FIG>, another embodiment of a catheter assembly is generally indicated at <NUM>. The catheter assembly <NUM> comprises a catheter tube <NUM>, and an expandable unit <NUM> attached to a distal end portion of the catheter tube. In the illustrated embodiment, the catheter tube <NUM> is received in a retractable sheath <NUM> such that the expandable unit <NUM> can be received in the sheath when the sheath is in an extended position (distally), and the expandable unit can be disposed outside of the sheath when the sheath is in a retracted position (proximally) (<FIG>). The expandable unit <NUM> functions similarly to the balloons of the previous embodiments to contact the interior wall of a vessel when the expandable unit is fully expanded to cover a perforation in a body lumen. Additionally, the catheter tube <NUM> may define a lumen <NUM> for receiving a guidewire (not shown) to facilitate delivery of the catheter assembly <NUM> through the patient's vessel.

The expandable unit <NUM> comprises a frame <NUM> defined by a plurality of struts <NUM> attached to the catheter tube <NUM>. In the illustrated embodiment, the struts <NUM> are attached to the catheter tube <NUM> at proximal and distal end of the struts and are free of attachment to the catheter tube between the proximal and distal ends. Alternatively, one of the proximal and distal ends of the struts <NUM> may be movably attached to the catheter tube <NUM> to facilitate expansion of the expandable unit <NUM>. The struts <NUM> comprise separate elongate flexible members that are configurable in a first (collapsed) configuration when the expandable unit <NUM> is received in the retractable sheath <NUM>, and in a second (expanded) configuration when the expandable unit is exposed out from the retractable sheath. In one embodiment, the struts <NUM> are formed from metal or polymer. In one embodiment, the struts <NUM> are formed from shape memory material (e.g., nitinol) and configured such that the second (expanded) configuration is their natural state when attached to the catheter tube <NUM>. Therefore, the struts <NUM> are biased toward the second (expanded) configuration and will return to this configuration when the restraint of the retractable sheath <NUM> is removed. In the illustrated embodiment, there are four struts <NUM> attached to the catheter tube <NUM>, and each strut is equally spaced circumferentially around the catheter tube. However, another number of struts may be used without departing from the scope of the disclosure. For instance, three struts or more than four struts could be used. In one embodiment, at least three struts <NUM> are attached to the catheter tube <NUM>. Additionally, the struts <NUM> may have other spacing around the catheter tube <NUM>. For example, the struts may be asymmetrically spaced around the catheter tube.

Also, while the illustrated embodiment shows a retractable sheath <NUM> that is movable to expose the expandable unit <NUM>, the catheter assembly <NUM> could be configured to include an actuating sleeve (not shown) rather than a retractable sheath. In this embodiment, the actuating sleeve can be movable to engage the expandable unit <NUM> causing the expandable unit to expand from a first configuration, such as the configuration shown in <FIG>, to a second, fully expanded configuration, shown in <FIG>. The structure of the actuating sleeve may be substantially similar to the retractable sheath <NUM> except that the struts <NUM> would be attached to the actuating sleeve and the actuating sleeve would not be sized to receive the expandable unit <NUM> and instead would be sized to press against proximal ends of the struts <NUM> causing the struts to bow outward, expanding the expandable unit. Still other means for moving the expandable unit <NUM> between collapsed and expanded configurations are envisioned.

A cover <NUM> may extend between two adjacent struts <NUM>. The cover <NUM> may be attached to the two adjacent struts <NUM> along an entire length of the struts or along only a part of the length of the struts. However, the cover <NUM> does not extend between all the struts <NUM> such that a space between at least two of the struts remains free of a cover. As such, a passage or perfusion channel <NUM> (<FIG>) is created between the struts <NUM> that are not connected with a cover. Therefore, fluid may pass between those struts <NUM> for delivery to locations downstream of the expandable unit <NUM>. In one embodiment, the cover <NUM> surrounds only about <NUM>% (i.e., <NUM> degrees) of a circumference of the catheter tube <NUM>. In one embodiment, the cover <NUM> surrounds less than about <NUM>% of the circumference of the catheter tube <NUM>. In one embodiment, the cover <NUM> surrounds less than about <NUM>% of the circumference of the catheter tube <NUM>. In one embodiment, the cover <NUM> surrounds less than about <NUM>% of the circumference of the catheter tube <NUM>. In one embodiment, the cover <NUM> surrounds less than about <NUM>% of the circumference of the catheter tube <NUM>.

The cover <NUM> comprises a flexible sheet of material configured to be folded when the expandable unit <NUM> is in the first (collapsed) configuration, and to unfold when the expandable unit is in the second (expanded) configuration. In one embodiment, the cover <NUM> comprises balloon material. In one embodiment, the cover <NUM> comprises metal scaffold material. The cover <NUM> could be formed from other materials without departing from the scope of the disclosure. The cover <NUM> provides structure for contacting the interior wall of a vessel when the expandable unit <NUM> is fully expanded to cover a perforation in the vessel. The cover <NUM> may also be coated with a medicament (e.g., hydrogel and a drug) for local administration to the area around the perforation.

Additionally, or alternatively, support struts (not shown) may extend between adjacent struts <NUM> connected by the cover <NUM> to assist in maintaining the cover in a fully unfolded configuration when the expandable unit <NUM> is exposed from the retractable sheath <NUM>.

Modifications and variations of the disclosed embodiments are possible without departing from the scope of the invention defined in the appended claims.

When introducing elements of the present invention or the embodiment(s) thereof, the articles "a", "an", "the" and "said" are intended to mean that there are one or more of the elements.

Claim 1:
A catheter assembly (<NUM>) comprising:
a catheter tube (<NUM>) comprising a distal end portion, the catheter tube being sized and shaped for delivery through a body lumen of a subject; and
an expandable unit (<NUM>) attached to the distal end portion of the catheter tube, the expandable unit being configurable in a first, collapsed, configuration to facilitate delivery of the catheter assembly through the body lumen, and a second, fully expanded, configuration for contacting an interior wall of the body lumen to cover a perforation in the body lumen, the expandable unit defining at least one longitudinal channel (<NUM>) extending from a proximal end of the expandable unit to a distal end of the expandable unit when the expandable unit is in the fully expanded configuration to permit blood flow past the expandable unit;
wherein the expandable unit comprises a balloon and at least one blocking element (<NUM>) disposed over the balloon limiting expansion of a longitudinal section of the balloon in the fully expanded configuration, the blocking element forming the at least one longitudinal channel,
characterised in that
the blocking element is formed integrally with the catheter tube.