Patent Description:
The disclosure relates generally to medical devices and methods of use. Embodiments of the invention include devices for performing thrombectomy or embolectomy in the internal carotid artery and other vessels of a patient.

Mechanical thrombectomy is a procedure that removes clots through endovascular intervention to restore blood flow to the brain during acute ischemic stroke. Acute Ischemic Stroke ("AIS") can be caused by thrombus, embolus or other occlusions in regions of the internal carotid artery ("ICA") such as the Petrous segment, Cavernous segment or Cerebral segment, or the middle cerebral artery ("MCA"), such as the MCA bifurcation, the M1 segment, and the M2 segment. Approaches for performing thrombectomy or embolectomy to treat AIS include accessing the vasculature and navigating a balloon guiding catheter to the carotid artery at a location upstream from the occlusion, typically at a proximal location in the artery such as the cervical segment of the ICA. After the balloon is inflated to provide antegrade blood flow cessation, retrieval devices can be passed through the balloon guide catheter to retrieve the embolus. Thrombectomy tools such as stent retrievers, aspiration catheters, or both can be delivered directly to the embolus through the guiding catheter to complete the retrieval process, after which the balloon is deflated and the retrieval and guide catheters retracted to the access point.

These thrombectomy procedures may involve placing a sheath through an arteriotomy in the patient's common femoral artery, and delivering the guiding catheter to the ICA through the sheath. In some cases, the arteriotomy may be located in an artery other than the common femoral artery. For example, an <NUM>-<NUM> French (Fr) inner diameter (ID) (<NUM>-<NUM> inches) sheath having a length on the order of twenty-five centimeters can be used to provide the access to the arterial tree through the arteriotomy. A balloon guiding catheter having a <NUM>-<NUM> Fr outer diameter (OD) (<NUM>-<NUM> inches), commonly about ninety centimeters in length, can then be delivered to the ICA through the sheath. An arteriotomy of <NUM>-<NUM> inches may be required for the sheath during procedures of these types. Unfortunately, these relatively large arteriotomies can enhance the risk of bleeding, especially since patients undergoing these procedures may be receiving thrombolytics that may increase the risks of hemorrhagic complications.

Distal access aspiration catheters (e.g., up to about <NUM> inch OD) are sometimes used during thrombectomy in the ICA. Such distal aspiration catheters include the ACE <NUM> from Penumbra, Inc. and the Sophia Plus from Microvention, Inc. For example, during these procedures the distal aspiration catheter can inserted with the end positioned at the distal middle cerebral artery. Other thrombectomy tools such as stent retrievers are sometimes delivered to the intracranial vasculature through distal access catheters used in this manner, or directly through the guide catheter. However, balloon guiding catheters have IDs that are too small to accommodate these distal aspiration catheters. Other known balloon guide catheters include the Cello devices from Medtronic, Inc. , and the Flowgate2 device from Stryker Neurovascular. The relatively long period of time required to place a sheath and then a balloon guide catheter can detract from the benefits of this treatment.

Stent retrievers and other endovascular tools are sometimes placed in the ICA or other vasculature using guiding sheaths that do not have balloons. Guiding sheaths are typically about ninety centimeters in length. These devices act as a combination of access sheath and guiding catheter. The need for a separate sheath is obviated by the use of these guiding sheaths since they are sufficiently long to provide access to the target vessel. Although guiding sheaths do not provide arterial occlusion, they can be rapidly placed.

International Publication No. <CIT> describes a balloon guiding sheath that includes an inflation lumen located between an inner tube and an outer tube. International Publication No. <CIT>describes a balloon catheter that includes an annular fluid path between a tubular inner member and a tubular outer member, where passages through the wall of the outer member forms a fluid pathway between the annular fluid path and a balloon interior.

The disclosure includes a balloon guiding sheath comprising an elongated sheath comprising a proximal end, a distal end, an inner tube extending between the proximal end and the distal end, an outer tube surrounding the inner tube and extending between the proximal end and the distal end, an access port located adjacent the proximal end, a distal port located adjacent the distal end, and a working lumen extending through an interior portion of the elongated sheath between the access port and the distal port; an inflatable balloon located on an outer surface of the elongated sheath adjacent the distal end, the inflatable balloon being fluidly coupled to an inflation lumen extending between the inflatable balloon and an inflation port located adjacent the proximal end; and a plurality of inflation holes extending through a side wall of the elongated sheath, wherein the plurality of inflation holes fluidly couple the inflatable balloon to the inflation lumen. The elongated sheath may be sized and configured to enable direct insertion into a patient's vasculature through an arteriotomy in at least one of a carotid artery and vertebral artery to position the inflatable balloon at a target site.

According to the invention, the balloon guiding sheath further comprises an inflation trough located on the outer tube, wherein the inflation trough facilitates fluid coupling between each inflation hole of the plurality of inflation holes. The inflation trough may rotationally extend around at least a portion of a perimeter of the outer tube to fluidly couple two inflation holes of the plurality of inflation holes. In some embodiments, the inflation trough rotationally extends <NUM>-degrees around the perimeter of the outer tube to fluidly couple each inflation hole of the plurality of inflation holes. The elongated sheath may be elongate along a first direction, and the inflation trough may rotationally extend along a second direction that is perpendicular to the first direction.

In some embodiments, the plurality of inflation holes are substantially symmetrically spaced around the outer tube. The plurality of inflation holes and the inflation trough may be arranged and configured to facilitate substantially symmetrical inflation of the inflatable balloon. In some embodiments, the inflation trough is located between the outer tube and the inflatable balloon. The inflation trough may be located adjacent the distal end of the elongated sheath. In some embodiments, the inflation trough is located closer to a distal portion of the inflatable balloon than a proximal portion of the inflatable balloon.

In some embodiments, the elongated sheath is elongate along a first direction, and the inflation trough defines a depth radially extending along a second direction that is perpendicular to the first direction. According to the invention, the elongated sheath is elongate along a first direction, the plurality of inflation holes each define a first width extending along the first direction, and the inflation trough defines a second width extending along the first direction, and wherein the first width is greater than the second width. The elongated sheath may define a generally constant outer diameter from the proximal end to the distal end.

The disclosure also includes a method (not in accordance with the claimed invention) of using a balloon guiding sheath comprising an elongated sheath comprising a proximal end, a distal end, an inner tube extending between the proximal end and the distal end, an outer tube surrounding the inner tube and extending between the proximal end and the distal end, an access port located adjacent the proximal end, a distal port located adjacent the distal end, a working lumen extending through an interior portion of the elongated sheath between the access port and the distal port, an inflatable balloon located on an outer surface of the elongated sheath adjacent the distal end, the inflatable balloon being fluidly coupled to an inflation lumen extending between the inflatable balloon and an inflation port located adjacent the proximal end, a plurality of inflation holes extending through a side wall of the elongated sheath that fluidly couple the inflatable balloon to the inflation lumen, and an inflation trough located on the outer tube, the inflation trough configured to facilitate fluid coupling between each inflation hole of the plurality of inflation holes. In some embodiments (not in accordance with the claimed invention), the method comprises inserting the balloon guiding sheath directly into a patient's vasculature through an arteriotomy in at least one of a carotid artery or a vertebral artery; advancing the balloon guiding sheath through the patient's vasculature and positioning the distal end at a target site; and inflating the inflatable balloon with at least one of fluid and media via the plurality of inflation holes and the inflation trough.

In some embodiments (not in accordance with the claimed invention), the method further comprises substantially symmetrically inflating the inflatable balloon via the plurality of inflation holes and the inflation trough. The method may include applying a substantially even inflation force into the inflatable balloon, via the plurality of inflation holes and the inflation trough, whereby the inflation force radially extends around a perimeter of the elongated sheath and the inflation force is directed away from the elongated sheath to thereby substantially symmetrically inflate the inflatable balloon. In some embodiments, the method includes maintaining a substantially constant and even pressure within the inflatable balloon.

In some embodiments (not in accordance with the claimed invention), wherein prior to the inflating the distal end of the elongated sheath is located in a first position with respect to the target site, the method further comprises, while inflating, maintaining a location of the distal end of the elongated sheath such that the distal end is substantially located in the first position during the inflating. The method may include, after inflating, maintaining the location of the distal end of the elongated sheath such that the distal end is still substantially located in the first position after the inflating.

In some embodiments (not in accordance with the claimed invention), the inflating comprises injecting, via the inflation port, at least one of fluid and media into the inflation lumen through the plurality of inflation holes and the inflation trough and into the inflatable balloon.

The elongated sheath may be elongate along a first direction, and the inflation trough may define a depth radially extending along a second direction that is perpendicular to the first direction, and the method may further comprise sending the at least one of fluid and media through the inflation lumen along the first direction; sending the at least one of fluid and media through the plurality of inflation holes along the second direction; sending the at least one of fluid and media through the inflation trough rotationally around the outer tube; and sending the at least one of fluid and media radially along the second direction away from the elongated sheath to thereby inflate the inflatable balloon.

In the drawings, like reference characters denote corresponding features consistently throughout similar embodiments.

The scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein (not in accordance with the claimed invention), the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein.

There is a continuing need for improved devices and methods for performing mechanical revascularization such as thrombectomy and embolectomy in the ICA and other vasculature. In particular, there is a need for such devices and methods that provide effective navigation to the target artery, support while advancing retrieval devices, and rapid flow arrest. Devices and methods of these types that can improve the efficiency of health care delivery would be especially desirable.

<FIG> illustrates a diagrammatic view of a patient <NUM> undergoing a thrombectomy procedure using a balloon guiding sheath <NUM>, which, in many embodiments, is a balloon guide catheter capable of direct arterial access without an introducer sheath. As shown in <FIG>, in some embodiments, the balloon guiding sheath <NUM> is sized and configured to be inserted in an arteriotomy located on the thigh of the patient <NUM> in order to reach a target site via femoral access. The arteriotomy may be located in another area of the patient's <NUM> vasculature <NUM>, such as near the groin of the patient <NUM> in order to reach the target site via the patient's <NUM> femoral artery. In some embodiments, the arteriotomy is located near the wrist of the patient <NUM> to reach the target site via transradial arterial access. The arteriotomy may also be located in the patient's <NUM> vertebral artery. In many embodiments, the target site is located in a carotid artery of the patient <NUM>.

As shown in <FIG> and as will be discussed in greater detail later in the disclosure, in some embodiments the balloon guiding sheath <NUM> includes an inflatable balloon <NUM>, which, in many embodiments, is located on an outer surface of an elongated sheath <NUM> (not shown in <FIG>) and near a distal end of the elongated sheath <NUM>. The balloon guiding sheath <NUM> may also include an access port <NUM> and an inflation port <NUM>, both of which may be located near a proximal end of the elongated sheath <NUM>. In some embodiments, the balloon guiding sheath <NUM> includes a distal port <NUM> located near a distal end of the elongated sheath <NUM>.

<FIG> illustrates a perspective view of the balloon guiding sheath <NUM> located inside the vasculature <NUM>. Specifically, <FIG> includes the common carotid artery ("CCA") 44a, which branches into the internal carotid artery ("ICA") 44b and the external carotid artery ("ECA") 44c. As shown, the middle cerebral artery ("MCA") 44d and the anterior cerebral artery ("ACA") 44e are located near a distal portion of the ICA 44b. <FIG> shows, in greater detail, the distal end <NUM> of the elongated sheath <NUM>, including the distal port <NUM>, located adjacent a target site <NUM>. In many embodiments, the target site <NUM> is located adjacent an occlusion in a vessel, such as an embolus <NUM>, as illustrated by <FIG>. Occlusions, such as an embolus <NUM>, are commonly located in the ICA 44b and near the MCA 44d, as shown in <FIG>. As demonstrated by <FIG> as well as <FIG>, the elongated sheath <NUM> includes an inflatable balloon <NUM>, which is located adjacent the distal end <NUM>. In some embodiments, the inflatable balloon <NUM> extends to a distal edge of the elongated sheath <NUM>. The inflatable balloon <NUM> may also be located near, but not extend all the way to, the distal end <NUM>, as illustrated in <FIG>.

According to the invention, the inflatable balloon <NUM> is configured to inflate, thereby pausing a substantial amount of the blood flow through the vasculature <NUM> to the target site <NUM>. Methods of inflating the balloon <NUM> will be discussed later in the disclosure. Once blood flow has been reduced and/or temporarily stopped, the balloon guiding sheath <NUM> may be configured to remove the embolus <NUM> through the distal port <NUM>. Removal of the embolus <NUM> may be achieved through suction, as in an aspiration thrombectomy procedure, and/or with the use of an additional device that physically breaks up the embolus <NUM>, as in a mechanical thrombectomy procedure. In some embodiments, the additional device is inserted through the access port <NUM> of the balloon guiding sheath <NUM>, illustrated in <FIG>.

<FIG> also shows that, in some embodiments, the balloon guiding sheath <NUM> includes an inner tube <NUM> and an outer tube <NUM>. The outer tube <NUM> may substantially surround the inner tube <NUM>, and both the inner and outer tubes <NUM>, <NUM>, may extend between the proximal end and the distal end <NUM> of the elongated sheath <NUM>. The balloon guiding sheath <NUM> may also include a working lumen <NUM>, which, in some embodiments, extends through an interior portion of the elongated sheath <NUM> between the distal port <NUM> and the access port <NUM>. The working lumen <NUM> may be configured to enable removal of an embolus <NUM> by providing a passageway for suction and/or an additional device used for mechanical thrombectomy.

<FIG> illustrates another perspective view of the balloon guiding sheath <NUM>, according to some embodiments. As shown, according to the invention, the inflatable balloon <NUM> and the distal port <NUM> are located at and/or adjacent the distal end <NUM> and the access port <NUM> and inflation port <NUM> are located at and/or adjacent the proximal end <NUM>. The inflation port <NUM> is configured to enable inflation of the inflatable balloon <NUM>. In some embodiments, inflation of the inflatable balloon <NUM> is achieved by the injection of at least one of fluid and media through the inflation port <NUM>. The inflatable balloon <NUM> is located on an outer surface of the elongated sheath <NUM>, and may wrap around substantially an entire circumference of the elongated sheath <NUM>. As shown in <FIG>, in some embodiments, the inflatable balloon <NUM> is located on top of additional components of the elongated sheath <NUM>. These additional components will be discussed in more detail with reference to <FIG>, as indicated in <FIG>.

In many embodiments, the elongated sheath defines a generally constant outer diameter from the proximal end <NUM> to the distal end <NUM>. The balloon guiding sheath <NUM> may define a length of about ninety centimeters.

<FIG> show perspective views of a portion of the elongated sheath <NUM>, including at least one inflation hole <NUM> and an inflation trough <NUM>. It should be noted that, for ease of illustrating the at least one inflation hole <NUM> and the inflation trough <NUM>, <FIG> do not include the inflatable balloon <NUM> and the distal most portion of the elongated sheath <NUM>. As will be described in greater detail, according to the invention the elongated sheath <NUM> comprises a plurality of inflation holes <NUM> configured to enable substantially symmetrical inflation of the inflatable balloon <NUM>. It should be noted that "symmetrical inflation" is intended to indicate radial symmetry of the inflated balloon <NUM>. As such, when inflated in a "substantially symmetrical" manner, the inflatable balloon <NUM> comprises a substantially consistent diameter from a proximal portion to a distal portion of the balloon <NUM>. As illustrated in <FIG>, in some embodiments, the elongated sheath <NUM> comprises three inflation holes 38a, 38b, and 38c. The inflation trough <NUM> may also be configured to work with the at least one inflation hole <NUM> to achieve inflation of the inflatable balloon <NUM>, in some embodiments, the inflation trough <NUM> aids in achieving substantial symmetrical inflation of the inflatable balloon <NUM>.

<FIG> also shows, in greater detail, the inner tube <NUM> and outer tube <NUM> previously mentioned with reference to <FIG>. It should be noted that the outer tube <NUM> and inner tube <NUM> are illustrated with dashed lines to represent that the portion of the elongated sheath <NUM> included in <FIG> does not necessarily extend to the distal end <NUM>. <FIG> also includes the working lumen <NUM>, which, in some embodiments, extends through an interior portion of the elongated sheath <NUM> between the distal port <NUM> and the access port <NUM>.

<FIG> illustrates a similar view as that of <FIG>, but also includes interior elements (shown in dashed lines) of the balloon guiding sheath <NUM>, including the working lumen <NUM>, the inflation lumen <NUM>, the at least one inflation hole <NUM>, and the inflation trough <NUM>. In many embodiments, the balloon guiding sheath <NUM> comprises an inflation lumen <NUM> that extends between the inner tube <NUM> and the outer tube <NUM>. The inflation lumen <NUM> may be configured to carry the at least one of fluid and media from the inflation port <NUM>, shown in <FIG>, to the inflatable balloon <NUM>, thereby enabling inflation of the inflatable balloon <NUM>. The fluid coupling between the inflation lumen <NUM> and the inflatable balloon <NUM> may also enable deflation of the balloon <NUM> by withdrawing the at least one of fluid and media from the balloon <NUM>, through the inflation lumen <NUM>, and out through the inflation port <NUM>.

According to the invention, the inflation lumen <NUM> is fluidly coupled to the inflatable balloon <NUM> via at least one of the inflation holes <NUM> and the inflation trough <NUM>. <FIG> illustrates the fluidly coupled areas, which are distinguished from the other components with shading. It should be noted that, in some embodiments, the inflation lumen <NUM> surrounds the working lumen <NUM>. As such, <FIG> may appear to show shading of the working lumen <NUM>. However, this shaded area actually represents the inflation lumen <NUM> and in many embodiments, the working lumen <NUM> is not fluidly coupled to the inflation trough <NUM> and the at least one inflation hole <NUM>.

According to the invention, the elongated sheath <NUM> comprises a plurality of inflation holes <NUM> located adjacent a distal portion of the elongated sheath <NUM>. In some embodiments, and as illustrated by <FIG>, the elongated sheath <NUM> comprises three inflation holes 38a, 38b, and 38c substantially evenly spaced around, and extending through, a side wall of the elongated sheath <NUM>. The side wall may be the outer tube <NUM>, such that the outer tube <NUM> defines the at least one inflation holes <NUM>. In some embodiments, the elongated sheath <NUM> comprises at least one inflation hole <NUM> substantially symmetrically spaced around the outer tube <NUM> of the elongated sheath <NUM>. The elongated sheath <NUM> may comprise a number other than three inflation holes (e.g. such as two holes, four holes, five holes, nine holes, twenty-five holes), which may be substantially evenly spaced from one another.

In many embodiments, each inflation hole <NUM> of the plurality of inflation holes are configured to fluidly couple to one another via at least one of the inflation lumen <NUM> and an inflation trough <NUM>. The plurality of inflation holes may also be configured to fluidly couple the inflation lumen <NUM> to the inflation trough <NUM>. In some embodiments, the inflation trough <NUM> is located between the inflatable balloon <NUM> and the outer tube <NUM>. <FIG> in particular highlights, via shading, the at least one inflation hole <NUM> and the inflation trough <NUM>. The inflation trough <NUM> may be thought of as an "etched out" layer of the outer tube <NUM>, such that outer tube <NUM> defines inflation trough <NUM> in some examples. The inflation trough <NUM> may also be located on the outer tube <NUM>. Fluid coupling between each inflation hole (i.e. in the illustrated embodiment, inflation holes 38a, 38b, and 38c) of the plurality of inflation holes allows at least one of fluid and media to flow around the inflation trough <NUM> in order to maintain substantially even and substantially constant pressure and/or inflation of the inflatable balloon <NUM>.

In some embodiments, the inflation trough <NUM> rotationally extends around at least a portion of a perimeter <NUM> (labeled in <FIG>, <FIG>, <FIG>, and <FIG>) of the outer tube <NUM> in order to fluidly couple at least two inflation holes <NUM> of the plurality of inflation holes. The inflation trough <NUM> may rotationally extend about <NUM>-degrees around the perimeter <NUM> of the outer tube <NUM> in order to fluidly couple each inflation hole <NUM> of the plurality of inflation holes. In some embodiments, the elongated sheath <NUM> is elongate along a first direction and the inflation trough <NUM> rotationally extends along a second direction that is perpendicular to the first direction. As such, the inflation trough <NUM> may extend radially out from the outer tube <NUM> in a direction perpendicular to the elongate direction of the elongated sheath. In some embodiments, the inflation trough <NUM> defines a depth radially extending along the second direction that is perpendicular to the first direction. The depth may be about <NUM> inches. In some embodiments, the inflation trough <NUM> defines a depth of <NUM> inches radially extending from an outer edge of the elongated sheath <NUM> toward the working lumen <NUM>. The inflation trough <NUM> may define a depth of about <NUM> inches.

In some embodiments, the inflation holes <NUM> are elongate along the first direction, such that the elongated sheath <NUM> is elongate along the same direction as the inflation holes <NUM>. Similar to the inflation trough <NUM>, the at least one inflation hole <NUM> may define a depth radially extending from an outer edge of the elongated sheath <NUM> radially inward toward the working lumen <NUM>. In some embodiments, the depth is <NUM> inches. The depth may be about <NUM> inches. In some embodiments, the depth of the inflation holes <NUM> is <NUM> inches.

Referring now to <FIG>, in some embodiments, at least one of fluid and media is configured to flow from the inflation port <NUM>, shown in <FIG> and <FIG>, through the inflation lumen <NUM>, and to the at least one inflation hole <NUM> and inflation trough <NUM>, in order to inflate the inflatable balloon <NUM> (not pictured). The arrows in <FIG> represent that the flow of fluid and/or media may proceed in a distal direction through the inflation lumen <NUM>, radially outward through the at least one inflation hole <NUM>, and then around the circumference of the elongated sheath <NUM> in the inflation trough <NUM>. As previously discussed, substantially even inflation of the inflatable balloon <NUM> may be achieved by the substantially even distribution of fluid and/or media around the elongated sheath <NUM>, which is enabled through the use of the at least one inflation hole <NUM> and inflation trough <NUM>. The at least one inflation hole <NUM> and inflation trough <NUM> may be used to achieve full inflation, partial inflation, and/or deflation of the inflatable balloon <NUM>. In some embodiments, partial inflation may be used to provide a layer of fluid and/or media between the inflatable balloon <NUM> and the outer surface of the elongated sheath <NUM> in an effort to reduce surface contact between the elongated sheath <NUM> and the inflatable balloon <NUM>, without actually inflating the balloon <NUM> to the extent necessary to reduce blood flow during a thrombectomy procedure.

<FIG> and <FIG> include the inflatable balloon <NUM>, and show it at different stages of inflation. <FIG> shows the balloon <NUM> at least one of substantially completely deflated and only partially inflated, while <FIG> demonstrates full inflation, according to some embodiments. <FIG> shows that, in some embodiments, the inflatable balloon <NUM> achieves substantially even inflation, which, as previously discussed, may comprise radial symmetry of the inflated balloon <NUM>. The inflatable balloon <NUM> may also inflate in an asymmetrical manner. <FIG> and <FIG> also include the distal end <NUM> of the elongated sheath <NUM>, and illustrate that, in some embodiments, the inflatable balloon <NUM> is located near the distal end <NUM>. The inflatable balloon <NUM> may be located closer to the distal end <NUM> than is shown in <FIG> and <FIG>. In some embodiments, the inflatable balloon <NUM> is located further from the distal end <NUM> than shown in the Figures. As also shown in <FIG>, <FIG> and <FIG> show that, in many embodiments, the inflatable balloon <NUM> is located substantially directly over the inflation trough <NUM> and the at least one inflation hole <NUM>.

<FIG> and <FIG> each show a side view of the balloon guiding sheath <NUM>, according to some embodiments. <FIG> and <FIG> may each also represent a top and/or bottom view of the sheath <NUM>. The figures include the elongated sheath <NUM>, the at least one inflation hole <NUM>, the inflation trough <NUM>, the distal end <NUM> of the elongated sheath <NUM>, the inflatable balloon <NUM>, and the proximal <NUM> and distal <NUM> portions of the balloon <NUM>. In some embodiments, the inflation trough <NUM> is located substantially evenly between the proximal portion <NUM> and the distal portion <NUM> of the inflatable balloon <NUM>. The inflation trough <NUM> may be located closer to the proximal portion <NUM> than the distal portion <NUM>. In some embodiments, the inflation trough <NUM> is located closer to the distal portion <NUM> than the proximal portion <NUM>. The at least one inflation hole <NUM> may be substantially centered below the inflatable balloon <NUM>, or may be located closer to the proximal portion <NUM> or the distal portion <NUM> of the balloon <NUM>. <FIG> shows the inflatable balloon <NUM> in a deflated state, while <FIG> shows the balloon <NUM> in an inflated state. In some embodiments, the balloon <NUM> is configured to inflate to a greater extent than illustrated by <FIG>. The balloon <NUM> may be configured to inflate to a lesser extent than illustrated by <FIG>.

<FIG> and <FIG> each show a cross-sectional view of the portion of the elongated sheath <NUM> designated in <FIG> and <FIG>, respectively. <FIG> and <FIG> each include the working lumen <NUM>, the inner tube <NUM>, the outer tube <NUM>, the at least one inflation hole <NUM>, the inflation trough <NUM>, the perimeter <NUM> of the outer tube <NUM>, and the inflatable balloon <NUM>. Similar to <FIG> and <FIG>, <FIG> shows the balloon <NUM> in a deflated state and <FIG> shows the balloon <NUM> in an inflated state. As previously discussed, in many embodiments, the at least one inflation hole <NUM> is a plurality of inflation holes <NUM> comprise three inflation holes 38a, 38b, and 38c substantially evenly spaced around the perimeter <NUM> of the outer tube <NUM>. <FIG> and <FIG> also show the inflation trough <NUM> located near the perimeter <NUM> of the outer tube <NUM>, as previously described. It should be noted that though the figures illustrate the inflatable balloon <NUM> in a generally circular shape, the balloon <NUM> may define any number of suitable shapes. In addition, <FIG> illustrates that, in many embodiments, the balloon <NUM> achieves substantially symmetrical inflation such that the balloon <NUM> comprises a consistent diameter. However, the balloon <NUM> may also inflate in an asymmetrical manner and comprise a varying diameter.

<FIG> and <FIG> show 2D and 3D side views, respectively, of a distal portion of the balloon guiding sheath <NUM>, according to some embodiments. As shown by the figures, according to the invention, each inflation hole <NUM> defines a first width <NUM> and the inflation trough <NUM> defines a second width <NUM>, and the first width <NUM> defines a larger width than the second width <NUM>. In some embodiments not covered by the invention as claimed, the second width <NUM> defines a larger width than the first width <NUM>. The first width <NUM> and the second width <NUM> may be relatively close in dimension, or may vary in dimension, as demonstrated in <FIG> and <FIG>. The elongated sheath <NUM> may be elongate along a first direction and both the first width <NUM> and the second width <NUM> extend along the first direction.

<FIG> and <FIG> illustrate a method (not according to the invention as claimed) of using the balloon guiding sheath <NUM>, according to some embodiments. As shown by step <NUM> of <FIG>, in some embodiments, the method comprises inserting the balloon guiding sheath <NUM> directly into a patient's <NUM> vasculature <NUM> through an arteriotomy <NUM>. As previously mentioned, the arteriotomy <NUM> may be located in a variety of arteries of a patient <NUM>, including but not limited to: a femoral artery, a vertebral artery, and a radial artery. <FIG> demonstrates the arteriotomy <NUM> located in the thigh of the patient <NUM> to enable femoral access into the vasculature <NUM>. Step <NUM> shows that the method may further comprise advancing the balloon guiding sheath <NUM> through the patient's <NUM> vasculature <NUM> and positioning the distal end <NUM> at a target site <NUM>. As discussed with reference to <FIG>, in some embodiments the target site <NUM> is located adjacent an embolus <NUM> in the ICA 44b, such that when the balloon guiding sheath <NUM> is located at the target site <NUM>, the sheath <NUM> is in position to remove the embolus <NUM>.

<FIG>, at step <NUM>, illustrates inflating the inflatable balloon <NUM> with at least one of fluid and media via the plurality of inflation holes and the inflation trough <NUM>. In some embodiments, inflating the balloon <NUM> comprises substantially symmetrically inflating the balloon. The inflatable balloon <NUM> may also be inflated in an asymmetrical manner. In order to achieve substantially symmetrical inflation, the method may comprise applying a substantially even inflation force into the inflatable balloon <NUM> via the plurality of inflation holes and the inflation trough <NUM>. In some embodiments, the inflation force radially extends around a perimeter <NUM> of the elongated sheath <NUM>, and the inflation force is directed away from the elongated sheath <NUM> to thereby substantially symmetrically inflate the inflatable balloon <NUM> with radial symmetry. The method may also comprise maintaining a substantially constant and even pressure within the inflatable balloon <NUM> in order to maintain even inflation.

In some embodiments, during step <NUM> of inflating the inflatable balloon <NUM>, the method comprises maintaining a location of the distal end <NUM> of the elongated sheath <NUM> such that the distal end <NUM> is substantially located in the first position adjacent the target site <NUM>, as illustrated in step <NUM> of <FIG>. After the inflating, the method may comprise continuing to maintain the location of the distal end <NUM> of the elongated sheath <NUM> such that the distal end <NUM> is still substantially located in the first position after inflating the inflatable balloon <NUM>.

As previously discussed, in many embodiments, the inflating (step <NUM>) comprises injecting, via the inflation port <NUM>, at least one of fluid and media into the inflation lumen <NUM>, through the plurality of inflation holes and the inflation trough <NUM>, and into the inflatable balloon <NUM>. In some embodiments, the elongated sheath <NUM> is elongate along a first direction and the inflation trough <NUM> defines a depth radially extending along a second direction that is perpendicular to the first direction. The inflating may comprise sending (e.g., introducing) the at least one of fluid and media through the inflation lumen <NUM> along the first direction, sending the at least one of fluid and media through the plurality of inflation holes along the second direction, sending the at least one of fluid and media through the inflation trough <NUM> rotationally around the outer tube <NUM>, and sending the at least one of fluid and media radially along the second direction away from the elongated sheath <NUM> to thereby inflate the inflatable balloon <NUM>.

It should be noted that the components of the balloon guiding sheath <NUM> may be formed of any suitable material including, but not limited to, hard and/or soft polymer plastics, rubber, metallic materials, and any combination thereof. Any biocompatible material that may be structurally suitable may be used to form any component or components of the balloon guiding sheath <NUM>. The fluid and/or media used to inflate the inflatable balloon <NUM> may comprise saline or a similar solution. In the event suction is used to remove an embolus <NUM>, an external vacuum force may be applied to the distal end <NUM> of the elongated sheath <NUM>, such as to the access port <NUM>. The inflatable balloon <NUM> may comprise one layer or may comprise a plurality of layers. In some embodiments, the elongated sheath <NUM> has a degree of flexibility to allow a user (i.e. a medical professional) to maneuver the balloon guiding sheath <NUM> through the vasculature <NUM> of a patient <NUM>.

Any portion of any of the steps, processes, structures, and/or devices disclosed or illustrated in one embodiment, flowchart, or example in this specification can be combined or used with or instead of any other portion of any of the steps, processes, structures, and/or devices disclosed or illustrated in a different embodiment, flowchart, or example. The embodiments and examples provided herein are not intended to be discrete and separate from each other.

The section headings and subheadings provided herein are nonlimiting. The section headings and subheadings do not represent or limit the full scope of the embodiments described in the sections to which the headings and subheadings pertain. For example, a section titled "Topic <NUM>" may include embodiments that do not pertain to Topic <NUM> and embodiments described in other sections may apply to and be combined with embodiments described within the "Topic <NUM>" section.

To increase the clarity of various features in certain figures, some features are not labeled in each figure. Additionally, some figures may omit features to more clearly illustrate various features.

The various features and processes described above may be used independently of one another, or may be combined in various ways. All possible combinations and subcombinations are intended to fall within the scope of this disclosure. In addition, certain method, event, state, or process blocks may be omitted in some implementations. The methods, steps, and processes described herein are also not limited to any particular sequence, and the blocks, steps, or states relating thereto can be performed in other sequences that are appropriate. For example, described tasks or events may be performed in an order other than the order specifically disclosed. Multiple steps may be combined in a single block or state. The example tasks or events may be performed in serial, in parallel, or in some other manner. Tasks or events may be added to or removed from the disclosed example embodiments. The example systems and components described herein may be configured differently than described. For example, elements may be added to, removed from, or rearranged compared to the disclosed example embodiments.

Conditional language used herein, such as, among others, "can," "could," "might," "may," "e.g.," and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. The terms "comprising," "including," "having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations and so forth. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each be present.

The term "and/or" means that "and" applies to some embodiments and "or" applies to some embodiments. Thus, A, B, and/or C can be replaced with A, B, and C written in one sentence and A, B, or C written in another sentence. A, B, and/or C means that some embodiments can include A and B, some embodiments can include A and C, some embodiments can include B and C, some embodiments can only include A, some embodiments can include only B, some embodiments can include only C, and some embodiments can include A, B, and C. The term "and/or" is used to avoid unnecessary redundancy.

The term "about" may be used to mean "approximately". For example, the disclosure includes "The inflation trough <NUM> may rotationally extend about <NUM>-degrees around the perimeter <NUM> of the outer tube <NUM> in order to fluidly couple each inflation hole <NUM> of the plurality of inflation holes. " In this context, "about <NUM>-degrees" is used to mean "approximately <NUM>-degrees". Any value between <NUM> and <NUM>-degrees may fall within the range of "about <NUM>-degrees" as used in the disclosure.

The term "substantially" may be used to mean "nearly completely" or "for the most part. " For example, the disclosure includes "the plurality of inflation holes are substantially symmetrically spaced around the outer tube. " In this context, "substantially symmetrically" means that the inflation holes are completely or nearly completely symmetrically spaced around the outer tube.

Claim 1:
A balloon guiding sheath (<NUM>), comprising:
an elongated sheath (<NUM>) comprising a proximal end (<NUM>), a distal end (<NUM>), an inner tube (<NUM>) extending between the proximal end (<NUM>) and the distal end (<NUM>), an outer tube (<NUM>) surrounding the inner tube (<NUM>) and extending between the proximal end (<NUM>) and the distal end (<NUM>), an access port (<NUM>) located adjacent the proximal end (<NUM>), a distal port (<NUM>) located adjacent the distal end (<NUM>), and a working lumen (<NUM>) extending through an interior portion (<NUM>) of the elongated sheath (<NUM>) between the access port (<NUM>) and the distal port (<NUM>);
an inflatable balloon (<NUM>) located on an outer surface of the elongated sheath (<NUM>) adjacent the distal end (<NUM>), the inflatable balloon (<NUM>) being fluidly coupled to an inflation lumen (<NUM>) extending between the inflatable balloon (<NUM>) and an inflation port (<NUM>) located adjacent the proximal end (<NUM>); and
a plurality of inflation holes (<NUM>,<NUM>,<NUM>) extending through a side wall of the elongated sheath (<NUM>), wherein the plurality of inflation holes (<NUM>,<NUM>,<NUM>) fluidly couple the inflatable balloon (<NUM>) to the inflation lumen (<NUM>),
wherein the elongated sheath (<NUM>) is sized and configured to enable direct insertion into a patient's vasculature through an arteriotomy (<NUM>) in at least one of a carotid artery or a vertebral artery to position the inflatable balloon (<NUM>) at a target site,
further comprising an inflation trough (<NUM>) defined by the outer tube (<NUM>), wherein the inflation trough (<NUM>) facilitates fluid coupling between the plurality of inflation holes (<NUM>,<NUM>,<NUM>),
wherein the elongated sheath (<NUM>) is elongate along a first direction, the plurality of inflation holes (<NUM>,<NUM>,<NUM>) each define a first width (<NUM>) extending along the first direction, and the inflation trough (<NUM>) defines a second width (<NUM>) extending along the first direction, and wherein the first width (<NUM>) is greater than the second width (<NUM>).