Patent Description:
Balloons may be used in the valves associated with the heart, including during Balloon Aortic Valvuloplasty (BAV) (as described in <NPL>) and Transcatheter Aortic Valve Implantation (TAVI)). For such a procedure, the inflated balloon may be designed to allow for continued blood flow, or perfusion. However, when the balloon is inflated, the heart valve is necessarily temporarily disabled. This can lead to disruptions in the blood flow, including by creating undesirable back flow.

Thus, it would be desirable to provide a perfusion balloon that can be used to regulate the flow of fluid during a procedure, especially when used in connection with a procedure involving a valve that is disabled as a result of the procedure or otherwise.

<CIT> discloses an inflatable structure for use in biological lumens and methods of making and using the same.

<CIT> discloses a medical system that has three basic components; a retractable sheet, a first balloon that has a centrally arranged hollow, and a collapsible/expandable support structure at the hollow.

<CIT> discloses a catheter assembly which may be provided with a catheter body and an inflatable balloon.

<CIT> discloses a delivery device for an annular implant that includes a balloon expansion mechanism and an annular implant having an adjustable dimension.

The technical effect of the disclosed embodiments may be considered to include achieving valving internal to a perfusion balloon, which creates an enhanced flow of fluid during the opening of the valve, enhanced blocking of the flow during the closing of the valve, and/or creates an easier manner to manufacture the balloon including the valve.

The present invention relates to the apparatus of claim <NUM>. The dependent claims refer to preferred embodiments. According to one aspect of the disclosure, an apparatus for performing a medical procedure in a vessel for transmitting a flow of fluid includes a shaft and an inflatable perfusion balloon supported by the shaft. The balloon includes an internal passage for permitting the fluid flow in the vessel while the perfusion balloon is in an inflated condition, and a valve connected to the shaft for controlling the fluid flow within the passage.

In one embodiment, the valve comprises a body having a generally frusto-conical shape in an expanded condition. The valve may comprise a single body, and may comprise one or more flaps. The valve may further include an aperture for receiving a portion of the balloon.

According to claim <NUM>, the balloon comprises a plurality of cells in a single cross-section bounding the internal passage, and the valve is positioned in a portion of the internal passage formed by the cells. Each cell may comprise a neck, and the valve is located in a space between the necks and the shaft. The valve may be connected to at least one of the necks.

The apparatus may further include a connector for connecting the valve to the balloon. The connector may be provided for connecting the valve to the balloon, the shaft or an associated sheath. The connector may comprise a tether in the form of a wire, fiber, ribbon, or like flexible structure.

Another aspect of the disclosure pertains to an apparatus for performing a medical procedure in a vessel for transmitting a flow of fluid. The apparatus includes a shaft and an inflatable perfusion balloon supported by the shaft. The balloon includes an internal passage for permitting the fluid flow in the vessel while the perfusion balloon is in an inflated condition. An elongated tube is adapted for partially collapsing to control the fluid flow within the passage, thereby forming a valve.

In one embodiment, the tube is at least partially connected to the balloon. The tube may include a distal portion connected to the balloon and a proximal portion not connected to the balloon. The proximal portion may have a continuous cross-section forming a full or at least partial circumferential seal with the balloon.

According to claim <NUM>, the balloon comprises a plurality of cells in a single cross-section. The tube is positioned in a part of the passage formed by the plurality of cells. Each of the cells may be rounded along an inner face At least a portion of the tube connected to the cells may comprise a cross-section in the form of a star having projections for positioning between adjacent cells and recesses between the projections for engaging the rounded cells.

Still a further aspect of the disclosure pertains to an apparatus for performing a medical procedure in a vessel for transmitting a flow of fluid. The apparatus comprises a shaft and an inflatable perfusion balloon supported by the shaft. The balloon includes an internal passage for permitting the fluid flow in the vessel while the perfusion balloon is in an inflated condition. The balloon includes a generally tapered portion extending toward the shaft. A valve is positioned in a space between the shaft and the balloon in the generally tapered portion for controlling the fluid flow within the passage.

In one embodiment, the valve comprises a body having a generally frusto-conical shape in an expanded condition. The valve may comprise a single body, or may comprise a plurality of flaps. The valve may include an aperture for receiving a portion of the balloon. The generally tapered portion for receiving the valve may be located at a distal end portion of the balloon, but could be located at the proximal end as well.

In yet another aspect, the disclosure pertains to an apparatus for performing a medical procedure in a vessel for transmitting a flow of fluid. The apparatus comprises a shaft and an inflatable perfusion balloon supported by the shaft. The balloon includes an internal passage for permitting the fluid flow in the vessel while the perfusion balloon is in an inflated condition, a valve for controlling the fluid flow within the passage, and a connector for connecting to the valve to control the position thereof.

In one embodiment, the connector comprises a tether extending between the valve and the balloon for preventing the valve from inverting. The connector may comprise a tether extending between the valve and the shaft or an associated sheath. The tether may comprise a wire, fiber, ribbon, or like flexible structure.

The invention disclosed pertains to an inflatable device in the nature of a perfusion balloon. A better understanding of the features and advantages of the invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings.

<FIG> shows an inflatable device <NUM> including a perfusion balloon <NUM> in an inflated condition, ready for use in connection with a procedure (but which balloon would normally be folded for purposes of delivery through the vasculature to a selected treatment area, such as the aortic valve). From viewing the inflated condition, it can be understood that the balloon <NUM> of the device <NUM> may have multiple inflatable cells 12a (eight shown, but any number may be provided) in at least a single cross-section of the balloon (see, e.g., <FIG>). A retainer, such as a tubular, flexible sheath or covering (not shown for purposes of clarity), may be provided over the central portion of the cells 12a to retain them in a generally annular configuration in the illustrated embodiment, and may also serve to protect the cells when contact is made with a stenosed valve or the like. The sheath or covering may be made non-compliant, such that inflation of the cells 12a expands the covering to engage an external structure, such as a valve forming part of the vasculature or other structure in a body.

The cells 12a may be individual or discrete, separately inflatable balloons. Each cell 12a having a separate inflation lumen via neck 12b, as noted, and also a neck 12c at the distal end, which form generally tapered portions of the balloon <NUM>. The cells 12a may be sealed at a distal tip (such as at the distal end of each neck 12c), or may be parts of a single balloon. The latter may be achieved by a segmented, elongated structure that is folded in a manner that causes the cells 12a to form a passage P extending along a central axis X, along which fluid such as blood may continue to flow, even when the balloon <NUM> is fully inflated (which may be done through a single inflation lumen, or each balloon could have its own inflation lumen). A full description of this type of balloon may be found in <CIT>. However, other forms of perfusion balloons could also be used, such as for example a tubular balloon, one having a peripheral (e.g., helical) channel for purposes of allowing fluid flow to occur during inflation, or any combination of these technologies.

In any case, the device <NUM> may also include an inner shaft or tube <NUM> including a lumen L extending along the central axis X, which may be adapted for receiving a guidewire for guiding the device to a treatment location. The inner tube <NUM> may form part of a catheter shaft or tube <NUM>, which includes a lumen N in which the inner tube <NUM> is positioned. The perfusion balloon <NUM> may in turn be supported by and attached to the catheter shaft <NUM>, such as at the proximal necks 12b forming the entrance to passage P, which may receive inflation fluid through the lumen N.

According to one aspect of the disclosure, the balloon <NUM> is adapted for selectively regulating the flow of fluid through the passage P. In one embodiment, this is achieved using a valve <NUM> comprising a selectively actuated body that, when actuated for occupying the passage P (<FIG>) such as the result of fluid flow in one direction (such as caused during diastole), substantially blocks it and thus retards or prevents fluid flow. When unactuated (folded down or collapsed; see valve <NUM>' in <FIG>, 3A), such as during systole, the valve <NUM> allows substantial flow through the passage P. The valve <NUM> may thus repeatedly and regularly restrict and allow fluid flow through the passage P when the balloon <NUM> is inflated, such as in the space including the aortic valve, and thus mimics the function of the otherwise disabled valve.

In the illustrated embodiment, the valve <NUM> comprises a single piece of a flexible material having a generally frusto-conical shape. However, the valve may take other forms, including as outlined further in the following description. In some embodiments, the valve <NUM> comprises a plurality of pieces of material, which may be separate or connected.

The valve <NUM> may be positioned anywhere within the passage P, such as adjacent to the open proximal end of it with the larger open end of the cone facing proximally. However, the valve <NUM> could alternatively be located at the distal end of the device <NUM>. The valve <NUM> may also be reoriented to open facing distally, if used transapically. Regardless of the particular position or orientation, the valve <NUM> is arranged to provide a one way valve function during a procedure using the device <NUM>.

In one embodiment, the material forming the valve <NUM> is connected at the innermost portion to the shaft or tube <NUM> passing through the balloon <NUM>. Thus, as can be understood from <FIG>, when of a frusto-conical shape, the material forming the valve <NUM> includes an opening 18a for receiving the shaft or tube <NUM>. The connection may be established by known bonding methods, such as adhesives, tapes, welding, or the like. The material forming the valve <NUM> may be otherwise substantially continuous, or could be provided in two or more segments in order to achieve a desired valving function (e.g., two segments to simulate a bicuspid valve, three to simulate a tricuspid, etc.) depending on the particular use. Alternatively, the valve <NUM> may be provided so as to be slidably connected to the tube <NUM>, such that it may move to and fro therealong to regulate flow.

Along the periphery of the valve <NUM>, the material is not connected to the interior of the balloon <NUM> (e.g. cells 12a). This will allow the valve to collapse and permit the fluid flow through passage P. However, it is possible to connect part of the periphery of the material forming the valve <NUM> to the balloon <NUM>, such as to one or more of the cells 12a or perhaps even the necks 12b, to allow for the valve <NUM> to only partially collapse. Adjustments can be made in this manner to provide a desired regulation of the fluid flow.

As shown in <FIG>, the valve <NUM> may also be connected to the device <NUM> by an optional connector <NUM>. The connector <NUM> may extend between the periphery of the valve <NUM> and the balloon <NUM>, such as at the junction between one cell 12a and the corresponding neck 12b. This connector <NUM> serves as a tether that prevents the valve <NUM> from inverting in the passage <NUM>, but is sufficiently sized so as to not prevent the desired movement between the actuated and non-actuated conditions. The connector <NUM> may comprise a ribbon, wire, fiber, or like structure having sufficient flexibility to achieve the desired function.

The valve <NUM> may also be connected to a structure external to the balloon <NUM>, such as a sheath <NUM> or the shaft <NUM>, for controlling the position of the valve <NUM>. This can be done using a connector <NUM>, similar to connector <NUM>, which thus forms a tether. This allows for the valve <NUM> to be forcibly collapsed by retracting the tube <NUM> or sheath <NUM>. This may be done to ensure that removal of the device <NUM> may be reliably achieved without interference from valve in the actuated or expanded condition.

Reference is now made to <FIG>, which illustrate a further embodiment of a possible valving arrangement for a perfusion balloon, such as the multi-cellular balloon <NUM> illustrated. In this embodiment, the valve <NUM> is formed of a body comprised of a flexible material in a generally frusto-conical shape when actuated (<FIG> and <FIG>) to restrict flow through passage P, and then collapsed to permit substantially unrestricted flow (<FIG> and <FIG>). However, as can be appreciated, the valve <NUM> in this embodiment is located at the distal end of the balloon <NUM> within the distal necks 12c of the balloon cells 12a. More specifically, the valve <NUM> is located in an internal space between the tube <NUM> and a cage formed by the necks 12c. The valve <NUM> could also be positioned at the proximal end of the balloon, such as in a similar location.

Again, the valve <NUM> may be formed as a single body (e.g., of a single piece of material), or may be formed as a series of flaps (such as, for example, eight flaps 18a-<NUM>, as indicated in <FIG>). In any case, the material may be connected along the inner portion to the tube <NUM>, such as by bonding (adhesive, welding (thermal or otherwise), tape, etc.). Alternatively or additionally, the material forming valve <NUM> may be bonded to form part of the distal tip 10a of the device <NUM>.

The material forming valve <NUM> may also be optionally connected to the balloon <NUM>, such as along one or more of the necks 12c, and for erecting in a space between the necks and the shaft <NUM> internal to the balloon. The connection may be established using bonds, such as by welding or adhesives (glue, tape, etc.), or by way of a mechanical connection. In one particular embodiment, the material forming the valve <NUM> is provided with one or more apertures, each for receiving a neck 12c of one of the balloon cells 12a or other structures connected to the balloon <NUM>. Thus, as shown in <FIG>, which is a similar view to <FIG>, the necks 12c may serve to support the valve <NUM> in a manner that allows it to at least partially collapse.

In this or other embodiments, the valve <NUM> material may also be provided with one or more slits S (see <FIG>) for selectively blocking and allowing fluid flow based on the relative flexing or bulging of the material forming the body of the valve caused by the resulting changes in fluid flow and pressure during systole and diastole. The slits S may extend radially, as shown, or may extend circumferentially, but other orientations are possible as well.

As noted previously, the material forming the body of the valve <NUM> may also be separated or divided into parts (note four quarters 18a-18d in <FIG>), each associated with one or more of the necks 12c along the periphery and partially or fully bonded to the tube <NUM> or tip 10a at the inner portion. The mechanical connection with the neck(s) 12c may additionally or alternatively be provided along the inner portion of the material forming valve <NUM> in any of these embodiments, as indicated in <FIG>, in which case a connection with the tube <NUM> may be optional.

In the above situations where there is a mechanical connection established, it can be appreciated that the necks 12c may help to erect the valve <NUM> to the operative condition when the balloon <NUM> is inflated, and further aid in collapsing it when deflated. In any case, the material forming the valve <NUM> may also be provided with properties to facilitate preferential folding when the balloon <NUM> is collapsed, and then expansion. This may be achieved, for example, by the use of different thickness of material to create living hinges or like structures that cause the material to fold or otherwise behave in a certain manner. The material of the valve body may also be provided with fold lines, pleats, beads, or supports to cause folding and unfolding to occur in a preferential manner to ensure that the valve <NUM> expands or collapses in the intended way to achieve the desired valving function.

The valve <NUM> may also take shapes other than frusto-conical.

For example, <FIG> illustrate a valve <NUM> having a body in the form of a generally cylindrical tube positioned in the passage P. The tube may be made of a film adhered at least partially to the interior of the balloon <NUM>, such as along the surfaces of cells 12a forming the passage P, but could also be located at other portions of the balloon, such as along the tapered sections formed by necks 12b, 12c. Specifically, a first portion of the tube (which may be distally located) having a continuous cross-section may be adhered to the balloon <NUM>, such as along portion A, while a second portion (which may be proximally located, and may also have a continuous cross-section) remains unattached to the balloon. The attachment may be achieved using bonding, such as adhesives (glue, epoxy, etc.), tape, welding, or other forms of thermal adhesion, etc., such that a circumferential seal is formed along the periphery of the valve <NUM>. Alternatively, the sealing may be such that only parts of the tube are adhered (such as to achieve collapsing in a manner that replicates the function of a bi-cuspid, tricuspid, or other desired form of collapsing, depending on the circumstances), with the understanding that aortic regurgitation may result when used in connection with the aortic valve. Again, if the tube <NUM> is positioned elsewhere, then the location of the attachment, such as portion A, would be repositioned accordingly (such as along necks 12b, 12c, with a discontinuous seal thus being formed).

Consequently, when fluid flows through the passage in the proximal direction, the valve <NUM> remains open, as shown in <FIG> and <FIG>. When the flow direction is reversed, the resulting negative pressure created may cause the unattached portion of the tube forming the valve <NUM> to collapse over the tube <NUM>, as shown in <FIG> and <FIG>, and thus hinder the flow of fluid through the passage P in the opposite direction. A one way valve is thus formed in a passive manner. Again, the orientation may be reversed depending on the particular use, and the positioning may be such that the unattached portion is not within the portion of the passage P bounded by cells 12a, but rather by necks 12b, 12c.

The valve <NUM> in this embodiment may be positioned anywhere along the passage P, and the overall length may be adjusted to achieve different performance characteristics (with a shorter length requiring less material and thus leading to enhanced trackability and sheath compatibility). To achieve the desired sealing along portion A, the tube forming the valve <NUM> may have an eight-sided star shape in cross-section (see <FIG>). In the case where each of the cells 12a has a rounded inner face, the valve <NUM> may have projections for positioning between adjacent cells and recesses between the projections for engaging the rounded cells. However, the valve <NUM> could also have a cross-section that is circular, square, rectangular, oval, triangular, or any other shape depending on the configuration of perfusion balloon <NUM>. The cross-section may also be continuous, tapered, stepped, or discontinuous. The orientation of the valve <NUM> may also be reversed for a transapical procedure.

Various materials may be used for forming the described structures, including as outlined in International Patent Application Publication No. <CIT>.

Claim 1:
An apparatus for performing a medical procedure in a vessel for transmitting a flow of fluid, comprising:
a shaft (<NUM>);
an inflatable perfusion balloon (<NUM>) supported by the shaft (<NUM>) and including an internal passage (P) for permitting the fluid flow in the vessel while the perfusion balloon (<NUM>) is in an inflated condition; and
a valve (<NUM>) connected to the shaft (<NUM>) for controlling the fluid flow within the internal passage (P),
wherein the balloon (<NUM>) comprises a plurality of cells (12a) in a single cross-section bounding the internal passage (P), and the valve (<NUM>) is positioned in a portion of the internal passage (P) bounded by the cells (12a).