Patent Description:
The present disclosure pertains to medical devices. More particularly, the present disclosure pertains to elongated intracorporeal medical devices including a guide extension catheter having an expandable balloon.

A wide variety of intracorporeal medical devices have been developed for medical use, for example, intravascular use. Some of these devices include guidewires, catheters, and the like. These devices are manufactured by any one of a variety of different manufacturing methods and may be used according to any one of a variety of methods. Examples of such device are disclosed in <CIT>, <CIT>, <CIT>, <CIT> and <CIT>. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and using medical devices.

An example guide extension catheter is disclosed. The invention relates to a guide extension catheter according to claim <NUM>. Further embodiments are set out in the dependent claims. The guide extension catheter comprises:.

The expandable balloon is disposed along an outer surface of the distal sheath for anchoring another device within the distal sheath and occluding flow of blood through the guide extension catheter.

Alternatively or additionally to any of the embodiments above, the expandable balloon is disposed along an inner surface of the distal sheath.

Alternatively or additionally to any of the embodiments above, further comprising an inflation tube in fluid communication with the expandable balloon.

Alternatively or additionally to any of the embodiments above, an inflation lumen is defined through a wall of the distal sheath.

Alternatively or additionally to any of the embodiments above, an inflation lumen is defined through the proximal shaft.

Alternatively or additionally to any of the embodiments above, the distal sheath includes a skived distal tip.

Alternatively or additionally to any of the embodiments above, further comprising a distal guide tube positioned within the distal sheath and extending to a position adjacent to a distal end of the distal sheath.

An example method (not part of the claimed invention) for accessing an intravascular target region is disclosed. The method comprises:.

Alternatively or additionally to any of the embodiments above, further comprising advancing a treatment device through the distal sheath.

Alternatively or additionally to any of the embodiments above, the expandable balloon is an occlusion balloon, and wherein expanding the expandable balloon includes expanding the expandable balloon against an inner surface of the guide catheter; expanding the expandable balloon against one or more of the blood vessel, the ostium, or the coronary artery; or both to substantially prevent blood flow therethrough.

Alternatively or additionally to any of the embodiments above, the expandable balloon is an anchoring balloon, and further comprising anchoring a medical device within the distal sheath with the anchoring balloon.

Alternatively or additionally to any of the embodiments above, further comprising an inflation tube in fluid communication with the expandable balloon, and wherein inflating the expandable balloon includes passing inflation media through the inflation tube.

Alternatively or additionally to any of the embodiments above, an inflation lumen is defined through a wall of the distal sheath, and wherein inflating the expandable balloon includes passing inflation media through the inflation lumen.

Alternatively or additionally to any of the embodiments above, an inflation lumen is defined through the proximal shaft, and wherein inflating the expandable balloon includes passing inflation media through the inflation lumen.

An example guide extension catheter is disclosed. The guide extension catheter, comprises:.

Alternatively or additionally to any of the embodiments above, the expandable balloon is an occlusion balloon disposed along an outer surface of the distal sheath.

Alternatively or additionally to any of the embodiments above, the expandable balloon is an anchoring balloon disposed along an inner surface of the distal sheath.

Alternatively or additionally to any of the embodiments above, at least a portion of the inflation lumen extends through a wall of the distal sheath.

Alternatively or additionally to any of the embodiments above, at least a portion of the inflation lumen extends through the proximal shaft.

The examples according to the <FIG> and <FIG> are not according to the invention and are present for illustration purposes only.

On the contrary, the intention is to cover all modifications falling within the scope of the disclosure.

Minimally-invasive cardiac interventions, such as percutaneous transluminal coronary angioplasty, are widely utilized throughout the world. These procedures may include the use of a guide catheter. For example, a guide catheter <NUM> may be advanced through a blood vessel such as the aorta A to a position adjacent to the ostium O of a (e.g., left and/or right) coronary artery CA as illustrated in <FIG>. When so positioned, a treatment catheter (e.g., balloon catheter, stent delivery system, etc.) may be advanced through the guide catheter <NUM> and into the coronary artery CA to a target location where the treatment catheter may be used to perform the appropriate cardiac intervention.

In order for the treatment catheter to efficiently reach the intended target location, maintaining the position of the guide catheter <NUM> at the ostium O of the coronary artery CA may be desirable. For example, given that the heart may be beating during the intervention (and/or other factors), the guide catheter <NUM> may lose its positioning or otherwise be shifted so that it no longer is positioned to efficiently guide the treatment catheter to the coronary arteries. Thus, a distal end <NUM> of the guide catheter <NUM> may be shifted away from the ostium O of the coronary artery CA. Because of the shift away from the ostium O, access to the coronary arteries CA may require repositioning of guide catheter <NUM> in order to bring the distal end <NUM> back into engagement with the ostium O of the coronary artery CA.

Disclosed herein are medical devices and methods for making and using medical devices that may improve access to the coronary arteries CA. For example, <FIG> illustrates a guide extension catheter <NUM> extending through the guide catheter <NUM> and beyond the distal end <NUM> of the guide catheter <NUM> into the coronary artery CA. Because, for example, the guide extension catheter <NUM> may extend beyond the distal end <NUM> of the guide catheter <NUM>, the guide extension catheter <NUM> may extend beyond the ostium O of the coronary artery CA and into a portion of the coronary artery CA. By extending beyond the ostium O, the guide extension catheter <NUM> may stabilize the positioning of the guide catheter <NUM> and allow for improved access to the coronary artery CA for a number of cardiac interventions.

<FIG> is a cross-sectional side view of the guide extension catheter <NUM>. Here it can be seen that the guide extension catheter <NUM> may include a proximal shaft <NUM>. The proximal shaft <NUM> may include a proximal portion <NUM> and a distal or ribbon portion <NUM>. The proximal portion <NUM> may have a lumen <NUM> defined therein. In some embodiments, the lumen <NUM> extends along the entire length of the proximal portion <NUM>. In other embodiments, the lumen <NUM> extends along only a portion of the length of the proximal portion <NUM>. In addition, the proximal portion <NUM> may include both proximal and distal openings (e.g., positioned at the proximal and distal end of the proximal portion <NUM>) such that the lumen <NUM> is open on both ends. Alternatively, one or both of the ends of the proximal portion <NUM> may be closed or otherwise sealed. For example, the distal end of the proximal portion <NUM> may be closed. In some embodiments, the proximal portion <NUM> may have an opening or port (not shown) formed in the wall of the proximal portion <NUM> and spaced from the proximal and/or distal end of the proximal portion <NUM>. The port may or may not be in fluid communication with the lumen <NUM>. A hub <NUM> may be attached to the proximal portion <NUM>.

A distal sheath <NUM> may be attached to the proximal shaft <NUM>. The distal sheath <NUM> may have a lumen <NUM> formed therein. In general, the lumen <NUM> (and/or the inner diameter of the distal sheath <NUM>) may be larger than the lumen <NUM> (and/or the inner diameter of the proximal portion <NUM>) and may be larger than the outer diameter of the proximal shaft <NUM>. Accordingly, the lumen <NUM> may be sufficiently large so as to allow a therapeutic catheter (e.g., balloon catheter, stent delivery system, etc.) to pass there through. For example, when the guide extension catheter <NUM> is positioned within the guide catheter <NUM>, the therapeutic catheter may extend within the guide catheter <NUM> alongside the proximal shaft <NUM> and through the lumen <NUM> of the distal sheath <NUM>.

The distal sheath <NUM> may include a body portion <NUM>. In some embodiments, the body portion <NUM> is made from one or more polymers such as those disclosed herein. This may include the use of polymers with a differing durometer along the length of the body portion <NUM>. For example, a more proximal section of the body portion <NUM> may include a polymer or a polymer blend with a higher durometer and a more distal section of the body portion <NUM> may include a polymer or a polymer blend with a lower durometer. Portions of all of the length of the body portion <NUM> may be loaded with or otherwise include a radiopaque material.

In some instances, one or more radiopaque markers <NUM> may be disposed along the body portion <NUM>. For example, a radiopaque marker <NUM> may be positioned adjacent to a distal end of the distal sheath <NUM>. In some of these embodiments, a radiopaque marker may be positioned adjacent to a proximal end of the distal sheath <NUM>. The distal sheath <NUM> may also include additional radiopaque markers positioned at suitable locations along its length. The shape, form, arrangement, and/or configuration of the radiopaque marker(s) <NUM> may also vary. For example, in some instances, the radiopaque marker <NUM> may be embedded in the body portion <NUM>. In addition, the radiopaque marker may have a length in the axial direction that is greater than a length or thickness in the radial direction. Other shapes and/or configurations are contemplated.

The body portion <NUM> may also include a reinforcing member <NUM>. The form of the reinforcing member <NUM> may vary. For example, the reinforcing member <NUM> may include a braid, coil, mesh, or the like made of a suitable material, such as a metal, a polymer, or the like.

An inner liner or layer <NUM> may be disposed along an inner surface of the body portion <NUM>. The form of the inner liner <NUM> may vary. For example, the inner liner <NUM> may be a lubricious liner or otherwise include a lubricious material such as polytetrafluoroethylene.

The distal sheath <NUM> may be attached to a ribbon portion <NUM> of the proximal shaft <NUM>. The arrangement and/or configuration of the attachment between the ribbon portion <NUM> and the distal sheath <NUM> may vary. For example, the distal sheath <NUM> may have an opening or lumen formed in a tube wall thereof and the ribbon portion <NUM> may be disposed within the opening. This may include necking, skiving, or pinching down the ribbon portion <NUM> and inserting the necked down portion into the opening. In some embodiments, inserting the ribbon portion <NUM> into the opening may secure the proximal shaft <NUM> to the distal sheath <NUM> via a mechanical bond. In some of these and in other embodiments, additional and/or alternative bonding may be utilized including those bonding mechanisms commonly used for medical devices (e.g., adhesive bonding, welding, thermal bonding, brazing, etc.).

Other attachment mechanisms are also contemplated for attaching the proximal shaft <NUM> to the distal sheath <NUM> including direct bonding (e.g., adhesive bonding, thermal bonding, welding, brazing, etc.), bonding that is facilitated by a third component such as a metal or polymer collar <NUM> that may be bonded between the ribbon portion <NUM> and the distal sheath <NUM>. The collar <NUM> illustrated in <FIG> (and in other figures) is meant to be schematic in nature and is not intended to limit the collar to any particular shape or configuration. A number of different collars are contemplated for securing the proximal shaft <NUM> and the distal sheath <NUM>. For example, <FIG> illustrates a collar 42a, which may be utilized with any of the guide extension catheters disclosed herein. For the purposes of this disclosure, any of the guide extension catheters disclosed herein may be considered to have a collar resembling the collar <NUM>, a collar resembling the collar 42a, or another suitable collar. The collar 42a may include a base 54a. A cutout 56a may be formed in the base 54a. In at least some instances, the ribbon portion <NUM> may be disposed within the cutout 56a and attached to the collar 42a using a suitable bonding technique (e.g., welding). The collar 42a may also include a plurality of arms or struts 58a that are oriented at an angle and/or otherwise take a helical configuration. In addition, the material used for the collar <NUM> and/or the collar 42a may vary. For example, in some instances, the collar <NUM> and/or the collar 42a may be made from a radiopaque material, such as Pt-Ir. This may allow the distal sheath <NUM> to not have a separate radiopaque marker adjacent to the proximal end of the distal sheath <NUM>, if desired.

The guide extension catheter <NUM> may also include a number of coatings that may, for example, reduce friction. For example, the proximal shaft <NUM> may have an inner and/or outer coating that includes a hydrophilic polymer that may reduce friction during tracking. An example coating may include BAYER CL-<NUM>, BIOSLIDE, NG-HPC, SLIP COAT, MDX, or the like. Other coating materials are contemplated including those disclosed herein.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheters disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>. The distal sheath <NUM> may also include a tip member <NUM>. The tip member <NUM> may be considered to be a soft and/or an atraumatic tip. In some embodiments, the tip member <NUM> may be a single layer of material. Alternatively, the tip member <NUM> may include an outer layer <NUM> and an inner layer <NUM>. The outer layer <NUM> and the inner layer <NUM> may be formed from the same material or from different materials. In some instances, the outer layer <NUM> and the inner layer <NUM> may include the same polymeric material and each may be loaded with the same or different radiopaque materials. For example, the inner layer <NUM> may include a polyether block amide loaded with approximately <NUM>-<NUM>% (e.g., about <NUM>%) by weight tungsten and outer layer <NUM> may include a polyether block amide loaded with approximately <NUM>-<NUM>% (e.g., <NUM>%) by weight bismuth subcarbonate. These are just examples. In other embodiments, the outer layer <NUM> and the inner layer <NUM> may be made from different materials.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheters disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>. The distal sheath <NUM> may also include a tip member <NUM>. In some instances, the tip member <NUM> may have a tip body <NUM> with a skived end. The skived end may help to facilitate delivery of the guide extension catheter <NUM> (and/or a device passing therethrough). In addition, the skived end may also be softer and atraumatic.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheters disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>. The distal sheath <NUM> may also include a tip member <NUM>. In some instances, the tip member <NUM> may have a tip body <NUM> with a skived end. The liner <NUM> may extend along the tip body <NUM>.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheters disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>. The distal sheath <NUM> may also include a tip member <NUM>. In some instances, the tip member <NUM> may have a tip body <NUM> with a skived end. A guidewire tube <NUM> may extend along at least a portion of the tip body <NUM>. The guidewire tube <NUM> may be used as a conduit for a guidewire extending through the distal sheath <NUM>.

In addition to the guidewire tube <NUM> or as an alternative to the guidewire tube <NUM>, a magnet or magnetic material may be disposed adjacent to or embedded within the tip body <NUM>. For example, a magnet may be disposed along the skived end of the tip body <NUM>. In other instances, the tip body <NUM> (e.g., whether skived or not) may include a magnetic material embedded therein (e.g., powdered magnetic material). In other instances, the tip body <NUM> (e.g., whether skived or not) may include a magnetic material and/or a radiopaque material embedded therein (e.g., powdered magnetic material and/or radiopaque material). In other instances, the tip body <NUM> (e.g., whether skived or not) may include a magnetic material embedded therein and/or a radiopaque marker (e.g., powdered magnetic material and/or a radiopaque marker). The magnetic material may allow the guide extension catheter <NUM> to hold onto a guidewire, yet release when a device approaches along the guidewire. This may allow a clinician to leave a guidewire in place during an intervention rather than remove the guidewire in order to advance a device past the guidewire tube <NUM>.

<FIG> illustrate example guide extension catheters that include an expandable member or balloon along an outer surface of the distal sheath. Such a balloon may function as an occlusion balloon that is designed to block the flow of blood. The balloon may be designed to be expanded against tissue along a blood vessel, against tissue adjacent to the coronary ostium, against a coronary artery, against a guide catheter through which the guide extension member is disposed, or a combination thereof. Different inflation structures may be utilized to inflate the balloon as discussed herein. While an outer balloon may be considered to be an occlusion balloon, the balloon may also function in anchoring the guide extension catheter to tissue and or other devices. To the extent that it is appropriate, structures disclosed with respect to other guide extension catheters disclosed herein (e.g., soft tips, skived tips, the collar 42a, the guidewire tube <NUM>, etc.) may be utilized with the guide extension catheters disclosed in <FIG>.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheters disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. As indicated above, the balloon <NUM> may function as an occlusion balloon. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. The inflation tube <NUM> may extend along the outer surface of the distal sheath <NUM> and then further along the proximal shaft <NUM> to a position where an inflation device (e.g., a device for passing inflation media therethrough) may be connected.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In some instances, the inflation tube <NUM> may be in fluid communication with the lumen <NUM> of the proximal shaft <NUM>. A gap <NUM> may be positioned at the distal end of the proximal shaft <NUM>. The gap <NUM> may help facilitate connection of the inflation tube <NUM> with the lumen <NUM> of the proximal shaft <NUM>.

<FIG> illustrates another example guide extension catheter <NUM> that may be similar in form and function to other guide extension catheter disclosed herein. The guide extension catheter <NUM> may include a proximal shaft <NUM> and a distal sheath <NUM>. A collar <NUM> may be used to secure the proximal shaft <NUM> to the distal sheath <NUM>. The distal sheath <NUM> may include a lumen <NUM>, a body portion <NUM>, a reinforcing member <NUM>, a liner <NUM>, and a radiopaque marker <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In some instances, the inflation tube <NUM> may be in fluid communication with an inflation lumen <NUM> formed in the distal sheath <NUM>. In other words, the distal sheath <NUM> may have the inflation lumen <NUM> defined in the wall thereof and the inflation tube <NUM> may be connected to the inflation lumen <NUM>. In some instances, the formation of the inflation lumen <NUM> may include the use of a mandrel placed along one or more of the layers of the distal sheath <NUM> during manufacturing of the distal sheath <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In some instances, the inflation tube <NUM> may be in fluid communication with the lumen <NUM> of the proximal shaft <NUM>. A gap <NUM> may be positioned at the distal end of the proximal shaft <NUM>. In some instances, the inflation tube <NUM> may also be in fluid communication with the inflation lumen <NUM> formed in the distal sheath <NUM>.

<FIG> illustrate guide extension catheters that include an expandable member or balloon along an inner surface of the distal sheath. Such a balloon may function as an anchoring balloon that is designed to anchor another device (e.g., a guidewire, catheter, stent delivery system, or the like) within the distal sheath. Different inflation structures may be utilized to inflate the balloon as discussed herein. While an inner balloon may be considered to be an anchoring balloon, the balloon may also function in occluding flow of blood through the guide extension catheter. To the extent that it is appropriate, structures disclosed with respect to other guide extension catheters disclosed herein (e.g., soft tips, skived tips, the collar 42a, the guidewire tube <NUM>, etc.) may be utilized with the guide extension catheters disclosed in <FIG>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. The inflation tube <NUM> may extend along an inner surface of the distal sheath <NUM> and then along the proximal shaft <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In some instances, the inflation tube <NUM> may be in fluid communication with the lumen <NUM> of the proximal shaft <NUM>. A gap <NUM> may be positioned at the distal end of the proximal shaft <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In some instances, the inflation tube <NUM> may be in fluid communication with an inflation lumen <NUM> formed in the distal sheath <NUM>.

An expandable balloon <NUM> may be coupled to the distal sheath <NUM>. An inflation tube <NUM> may be in fluid communication with the balloon <NUM>. In this example, the expandable balloon <NUM> is shown disposed along an outer surface of the distal sheath and positioned adjacent to a proximal end of the distal sheath <NUM>. This illustrates that the position of the balloon <NUM> may vary. In addition, the inflation mechanism utilized to inflate the balloon <NUM> may include structures similar to those disclosed herein (e.g., as shown in <FIG>). The balloon <NUM> may function to occlude and/or to anchor (e.g., anchor the guide extension catheter <NUM> to, for example, a guide catheter).

The materials that can be used for the various components of the guide extension catheters disclosed herein and the various components thereof disclosed herein may include those commonly associated with medical devices. For simplicity purposes, the following discussion makes reference to the distal sheath <NUM> and other components of the guide extension catheter <NUM>. However, this is not intended to limit the devices and methods described herein, as the discussion may be applied to other similar tubular members and/or components of tubular members or devices disclosed herein.

The distal sheath <NUM> and other components of the guide extension catheter <NUM> may be made from a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material. Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, DELRIN® available from DuPont), polyether block ester, polyurethane (for example, Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example, ARNITEL® available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as HYTREL® available from DuPont), polyamide (for example, DURETHAN® available from Bayer, CRISTAMID® available from Elf Atochem, VESTAMID®, or the like), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), Marlex high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene (for example REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-<NUM> (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. In some embodiments the sheath can be blended with a liquid crystal polymer (LCP). For example, the mixture can contain up to about <NUM> percent LCP.

Some examples of suitable metals and metal alloys include stainless steel, such as 304V, <NUM>, and 316LV stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL® <NUM>, UNS: N06022 such as HASTELLOY® C-<NUM>®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like); platinum enriched stainless steel; titanium; combinations thereof; and the like; or any other suitable material.

In at least some embodiments, portions or all of the guide extension catheter <NUM> may also be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are understood to be materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. This relatively bright image aids the user of the guide extension catheter <NUM> in determining its location. Some examples of radiopaque materials can include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloy, polymer material loaded with a radiopaque filler, and the like. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design of the guide extension catheter <NUM> to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into the guide extension catheter <NUM>. For example, the guide extension catheter <NUM>, or portions thereof, may be made of a material that does not substantially distort the image and create substantial artifacts (e.g., gaps in the image). Certain ferromagnetic materials, for example, may not be suitable because they may create artifacts in an MRI image. The guide extension catheter <NUM>, or portions thereof, may also be made from a material that the MRI machine can image. Some materials that exhibit these characteristics include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nitinol, and the like, and others.

<CIT> is mentioned as disclosing examples of known material.

Claim 1:
A guide extension catheter (<NUM>, <NUM>, <NUM>, <NUM>), comprising:
a proximal shaft (<NUM>, <NUM>, <NUM>, <NUM>) having a first outer diameter;
a distal sheath (<NUM>, <NUM>, <NUM>, <NUM>) attached to the proximal shaft (<NUM>, <NUM>, <NUM>, <NUM>) and having a second outer diameter greater than the first outer diameter;
wherein the distal sheath (<NUM>, <NUM>, <NUM>, <NUM>) is designed to extend past a coronary ostium and into a coronary artery so that another medical device can pass therethrough toward the coronary artery; and
an expandable balloon (<NUM>, <NUM>, <NUM>, <NUM>) coupled to the distal sheath (<NUM>, <NUM>, <NUM>, <NUM>),
wherein the expandable balloon (<NUM>, <NUM>, <NUM>, <NUM>) is disposed along an inner surface of the distal sheath (<NUM>, <NUM>, <NUM>, <NUM>), for anchoring another device within the distal sheath (<NUM>, <NUM>, <NUM>, <NUM>) and occluding flow of blood through the guide extension catheter (<NUM>, <NUM>, <NUM>, <NUM>).