Patent Description:
Arterial embolism is a sudden interruption of blood flow to an organ or body part due to an embolus, e.g., debris or a clot. During a surgical intervention, such as a cardiac intervention, a vascular intervention, or a coronary intervention, tissue, plaque, and/or other masses may be dislodged due to the intervention, resulting in an embolus. These emboli are capable of traveling far from their origins, migrating to other sites of the vasculature and resulting in potentially life threatening complications. For example, an embolus may travel through the carotid artery and inhibit the flow of blood to the brain, which may result in the death of brain cells, i.e., cause a stroke. A blockage of the carotid arteries is the most common cause of a stroke.

One interventional procedure that may result in an increased risk of arterial embolism is transcatheter aortic valve replacement ("TAVR"). Prosthetic heart valves that are collapsible to a relatively small circumferential size can be delivered into a patient less invasively than valves that are not collapsible. For example, a collapsible valve may be delivered into a patient via a tube like delivery apparatus such as a catheter, a trocar, a laparoscopic instrument, or the like. This collapsibility can avoid the need for a more invasive procedure such as full open chest, open heart surgery.

Collapsible prosthetic heart valves typically take the form of a valve structure mounted on a stent. There are two types of stents on which the valve structures are ordinarily mounted: a self-expanding stent and a balloon expandable stent. To place such valves into a delivery apparatus and ultimately into a patient, the valve must first be collapsed or crimped to reduce its circumferential size.

When a collapsed prosthetic valve has reached the desired implant site in the patient (e.g., at or near the annulus of the patient's heart valve that is to be replaced by the prosthetic valve), the prosthetic valve can be deployed or released from the delivery apparatus and re expanded to full operating size. For balloon expandable valves, this generally involves releasing the entire valve, assuring its proper location, and then expanding a balloon positioned within the valve stent. For self-expanding valves, on the other hand, the stent automatically expands as the sheath covering the valve is withdrawn.

In conventional delivery systems for self-expanding aortic valves, for example, after the delivery system has been positioned for deployment, the self-expanding prosthesis aortic valve may be released from an overlying sheath to allow the prosthetic aortic valve to expand into the native aortic valve to take over functioning of the native aortic valve.

During the deployment of the prosthetic heart valve, and in particular during the step of allowing the prosthetic heart valve to expand (or forcing the prosthetic heart valve to expand, for example via a balloon) into its final position in the native aortic valve, there is a risk that debris, such as plaque, may be dislodged from the anatomy and enter the flow of blood. In such scenarios, as noted above, it would be beneficial to be able to trap such debris and remove the debris from the body. However, even if such debris is not trapped and removed from the body, it may still be beneficial to deflect such debris so that the debris passes into the descending aorta. In other words, as described in greater detail below, if the debris cannot be trapped and removed from the body, it may still be a significant benefit to ensure that the debris avoids entering arteries branching from the ascending aorta.

<CIT> discloses an apparatus and procedure for trapping embolic debris.

According to the invention, a delivery device for a collapsible and expandable prosthetic heart valve includes an outer sheath extending from a proximal end to a distal end. A delivery sheath is positioned at the distal end of the outer sheath, the delivery sheath being sized and shaped to maintain the prosthetic heart valve in a collapsed condition therein. A filter sheath overlies a portion of the outer sheath. An intermediate sheath is positioned between the outer sheath and the filter sheath. An embolic filter has a proximal end coupled to the intermediate sheath, and a distal end that is not directly attached to the intermediate sheath. The embolic filter has a delivery condition in which the filter sheath overlies the embolic filter and the distal end of the embolic filter is in a collapsed condition, and a deployed condition in which the filter sheath does not overlie the embolic filter and the distal end of the embolic filter is in an expanded condition.

According to an aspect of the disclosure, a method of implanting a collapsible and expandable prosthetic aortic valve into a patient includes advancing a delivery device in the patient toward a native aortic valve annulus of the patient while the prosthetic aortic valve is maintained in a collapsed condition within a delivery sheath of the delivery device. Prior to deploying the prosthetic aortic valve, an embolic protection filter may be deployed from the delivery device into a position upstream of at least one ostium of an artery extending from an ascending aorta of the patient. The prosthetic aortic valve may be deployed into an expanded condition within the native aortic valve annulus while the embolic protection filter is deployed.

Particular embodiments of the present disclosure are described with reference to the accompanying drawings. In the figures and in the description that follow, like reference numerals identify similar or identical elements. As shown in the drawings and as described throughout the following description, when used in connection with a delivery device or associated components, the term "proximal" refers to the end of the device that is closer to the user and the term "distal" refers to the end of the device that is farther from the user.

<FIG> illustrates aorta <NUM>, the largest artery in the body, originating from the left ventricle (not shown) and extending down to the abdomen. Blood flows as indicated by arrow "A" from the left ventricle, through the aortic valve (not shown), through ascending aorta <NUM> to aortic arch <NUM>. Three major arteries branch from aortic arch <NUM>. Brachiocephalic artery <NUM> branches into right subclavian artery <NUM>, supplying blood to the right arm, and right common carotid artery <NUM>, supplying blood to the head and neck. Left common carotid artery <NUM> supplies blood to the head and neck. Left subclavian artery <NUM> supplies blood to the left arm. Blood from ascending aorta <NUM> not passing through one of these three arteries continues down descending aorta <NUM> as shown by arrow "B. " Variations of the anatomy illustrated in <FIG> are possible and sometimes are relatively common. For example, about <NUM>% of the population has a common brachiocephalic trunk, in which both common carotid arteries <NUM>, <NUM> and right subclavian artery <NUM> arise from a single trunk off aortic arch <NUM>. During interventional surgical, cardiac, and/or vascular procedures, there is a risk that emboli may break free and travel up ascending artery <NUM> and cause a blockage of brachiocephalic artery <NUM>, right common carotid artery <NUM>, and/or left common carotid artery <NUM>, causing reduced blood flow to the brain and possibly a stroke. Devices and methods described herein may be used during interventional procedures to capture and remove emboli from the body. Further, as noted above, even if such emboli or debris are not able to be trapped and removed from the body, it may be a significant benefit to ensure that the debris is deflected from entering the brachiocephalic artery <NUM> and left common carotid artery <NUM>, as such deflection may significantly reduce the risk of stroke or transient ischemic attach ("TIA").

Although so-called "embolic protection" devices exist in order to attempt to trap emboli during a cardiac intervention procedure, typically these devices are separate devices form the devices being used for the primary intervention, and as a result the use of a secondary embolic protection device may significantly increase both the complexity of the procedure and the length of the procedure. The devices described herein may mitigate increased complexity and duration that may otherwise occur when using an embolic protection device in conjunction with a TAVR procedure, at least partially due to the incorporation of the embolic protection features in the TAVR delivery device, described in greater detail below.

In order to assist in the understanding of TAVR valves and delivery devices, an exemplary valve and delivery device are briefly described. <FIG> shows a collapsible prosthetic heart valve <NUM>. The prosthetic heart valve <NUM> is designed to replace the function of a native aortic valve of a patient. Examples of collapsible prosthetic heart valves are described in <CIT>; and <CIT> and <CIT>. The prosthetic heart valve has an expanded condition, shown in <FIG>, and a collapsed condition.

Prosthetic heart valve <NUM> includes an expandable stent <NUM> which may be formed from any biocompatible material, such as metals, synthetic polymers or biopolymers capable of functioning as a stent. Stent <NUM> extends from a proximal or annulus end <NUM> to a distal or aortic end <NUM>, and includes an annulus section <NUM> adjacent the proximal end and an aortic section <NUM> adjacent the distal end. The annulus section <NUM> has a relatively small cross section in the expanded condition, while the aortic section <NUM> has a relatively large cross section in the expanded condition. Preferably, annulus section <NUM> is in the form of a cylinder having a substantially constant diameter along its length. A transition section <NUM> may taper outwardly from the annulus section <NUM> to the aortic section <NUM>. Each of the sections of the stent <NUM> includes a plurality of cells <NUM> connected to one another in one or more annular rows around the stent. For example, as shown in <FIG>, the annulus section <NUM> may have two annular rows of complete cells <NUM> and the aortic section <NUM> and transition section <NUM> may each have one or more annular rows of partial cells <NUM>. The cells <NUM> in the aortic section <NUM> may be larger than the cells <NUM> in the annulus section <NUM>. The larger cells in the aortic section <NUM> better enable the prosthetic valve <NUM> to be positioned without the stent structure interfering with blood flow to the coronary arteries.

Stent <NUM> may include one or more retaining elements <NUM> at the distal end <NUM> thereof, the retaining elements being sized and shaped to cooperate with female retaining structures provided on the deployment device. The engagement of retaining elements <NUM> with the female retaining structures on the deployment device helps maintain prosthetic heart valve <NUM> in assembled relationship with the deployment device, minimizes longitudinal movement of the prosthetic heart valve relative to the deployment device during unsheathing or resheathing procedures, and helps prevent rotation of the prosthetic heart valve relative to the deployment device as the deployment device is advanced to the target location and during deployment.

The prosthetic heart valve <NUM> includes a valve assembly <NUM> positioned in the annulus section <NUM>. Valve assembly <NUM> includes a cuff <NUM> and a plurality of leaflets <NUM> which collectively function as a one way valve. The commissure between adjacent leaflets <NUM> may be connected to commissure features <NUM> on stent <NUM>. <FIG> illustrates a prosthetic heart valve for replacing a native tricuspid valve, such as the aortic valve. Accordingly, prosthetic heart valve <NUM> is shown in <FIG> with three leaflets <NUM>, as well as three commissure features <NUM>. As can be seen in <FIG>, the commissure features <NUM> may lie at the intersection of four cells <NUM>, two of the cells being adjacent one another in the same annular row, and the other two cells being in different annular rows and lying in end to end relationship. Preferably, commissure features <NUM> are positioned entirely within annulus section <NUM> or at the juncture of annulus section <NUM> and transition section <NUM>. Commissure features <NUM> may include one or more eyelets which facilitate the suturing of the leaflet commissure to the stent. However, it will be appreciated that the prosthetic heart valves may have a greater or lesser number of leaflets and commissure features. Additionally, although cuff <NUM> is shown in <FIG> as being disposed on the luminal surface of annulus section <NUM>, it is contemplated that the cuff may be disposed on the abluminal surface of annulus section <NUM>, or may cover all or part of either or both of the luminal and abluminal surfaces of annulus section <NUM>. Both the cuff <NUM> and the leaflets <NUM> may be wholly or partly formed of any suitable biological material or polymer.

In operation, a prosthetic heart valve, including the prosthetic heart valve described above, may be used to replace a native heart valve, such as the aortic valve, a surgical heart valve or a heart valve that has undergone a surgical procedure. The prosthetic heart valve may be delivered to the desired site (e.g., near a native aortic annulus) using any suitable delivery device, including the delivery devices described below. During delivery, the prosthetic heart valve is disposed inside the delivery device in the collapsed condition. The delivery device may be introduced into a patient using a transfemoral, transapical or transseptal approach. Once the delivery device has reached the target site, the user may deploy the prosthetic heart valve. Upon deployment, the prosthetic heart valve expands into secure engagement within the native aortic annulus. When the prosthetic heart valve is properly positioned inside the heart, it works as a one-way valve, allowing blood to flow in one direction and preventing blood from flowing in the opposite direction.

Turning now to <FIG>, an exemplary transfemoral delivery device <NUM> for a collapsible prosthetic heart valve (or other types of self-expanding collapsible stents) has a catheter assembly <NUM> for delivering the heart valve to and deploying the heart valve at a target location, and an operating handle <NUM> for controlling deployment of the valve from the catheter assembly. The delivery device <NUM> extends from a proximal end <NUM> to a distal tip <NUM>. The catheter assembly <NUM> is adapted to receive a collapsible prosthetic heart valve (not shown) in a compartment <NUM> defined around an inner shaft <NUM> and covered by a distal sheath <NUM>. The inner shaft <NUM> extends through the operating handle <NUM> to the distal tip <NUM> of the delivery device, and includes a retainer <NUM> affixed thereto at a spaced distance from distal tip <NUM> and adapted to hold a collapsible prosthetic valve in the compartment <NUM>.

The distal sheath <NUM> surrounds the inner shaft <NUM> and is slidable relative to the inner shaft such that it can selectively cover or uncover the compartment <NUM>. The distal sheath <NUM> is affixed at its proximal end to an outer shaft <NUM>, the proximal end of which is connected to the operating handle <NUM>. The distal end <NUM> of the distal sheath <NUM> abuts the distal tip <NUM> when the distal sheath fully covers the compartment <NUM>, and is spaced apart from the distal tip <NUM> when the compartment <NUM> is at least partially uncovered.

The operating handle <NUM> is adapted to control deployment of a prosthetic valve located in the compartment <NUM> by permitting a user to selectively slide the outer shaft <NUM> proximally or distally relative to the inner shaft <NUM>, or to slide the inner shaft <NUM> relative to the outer shaft <NUM>, thereby respectively uncovering or covering the compartment with the distal sheath <NUM>. Operating handle <NUM> includes frame <NUM> which extends from a proximal end <NUM> to a distal end and includes a top frame portion 1030a and a bottom frame portion 1030b. The proximal end of the inner shaft <NUM> is coupled to a hub <NUM>, and the proximal end of the outer shaft <NUM> is affixed to a carriage assembly that is slidable within the operating handle along a longitudinal axis of the frame <NUM>, such that a user can selectively slide the outer shaft relative to the inner shaft by sliding the carriage assembly relative to the frame. Alternatively, inner shaft <NUM> may be actuated via hub <NUM> to cover or uncover the compartment. Optionally, an introducer sheath <NUM> is disposed over some or all of outer shaft <NUM>. The introducer sheath <NUM> may be attached to the outer shaft <NUM> or may be unattached. Additionally, introducer sheath <NUM> may be disposed over a majority of outer shaft <NUM> or over a minority of the outer shaft (e.g., over <NUM>% or less, over <NUM>%, etc.). Further, a stability layer may be provided between outer shaft <NUM> and introducer sheath <NUM>. The stability layer may be translationally fixed to a distal end portion of operating handle <NUM>, and may extend any desired length distally toward distal sheath <NUM>. The stability layer may optionally be more rigid than the outer shaft <NUM>. The stability layer may also be referred to as a stability tube, stability sheath, or an intermediate sheath herein.

Additionally, hub <NUM> may include a pair of buttons <NUM>, each attached to a clip <NUM> (<FIG>). Clips <NUM> on hub <NUM> may mate with voids <NUM> on frame <NUM> to ensure that the hub and the frame are securely coupled together. Optionally, hub <NUM> may also include a wheel <NUM>, which will be described in greater detail below.

A first mechanism for covering and uncovering the compartment <NUM> will be referred to as a "fine" technique as covering and uncovering occurs slowly with a high degree of precision. To allow for this technique, frame <NUM> defines an elongated space in which the carriage assembly may travel. The elongated space preferably permits the carriage assembly to travel a distance that is at least as long as the anticipated length of the prosthetic valve to be delivered (e.g., at least about <NUM>), such that the distal sheath <NUM> can be fully retracted off of the prosthetic valve.

The carriage assembly includes a main body and a threaded rod extending proximally therefrom along the longitudinal axis of the frame <NUM>. The threaded rod preferably is longer than the anticipated maximum travel distance of the carriage assembly within the elongated space (e.g., at least about <NUM>), such that the threaded rod does not fully withdraw from the elongated space during deployment of the prosthetic valve.

A deployment actuator <NUM>, shown in <FIG> as a wheel protruding from the upper and lower frames 1030a, 1030b is fixedly coupled to a first gear so that rotation of actuator <NUM> causes a corresponding rotation of the first gear. The first gear, in turn, is threadedly engaged on the threaded rod of the carriage. The first gear converts rotation of deployment actuator <NUM> into longitudinal translation of the threaded rod of the carriage and a corresponding translation of the main body of the carriage. Hence, rotation of actuator <NUM> in one direction (either clockwise or counterclockwise depending on the orientation of the threads on the threaded rod) causes the carriage assembly to translate proximally within the elongated space. Alternatively, the actuator <NUM> and the first gear may be integral with one another.

As outer shaft <NUM> is fixedly connected to the carriage assembly, translation of the carriage assembly results in a longitudinal translation of outer shaft <NUM> and with it distal sheath <NUM>. Thus, deployment actuator <NUM> is configured to provide for fine movement of outer shaft <NUM> for deployment and recapture of the prosthetic heart valve. As deployment actuator <NUM> protrudes from upper and lower frames 1030a, 1030b approximately halfway between the proximal and distal ends of the handle <NUM>, a user may readily rotate the actuator with his or her thumb and/or index finger.

Optionally, handle <NUM> further includes a resheathing lock <NUM> adapted to prevent any movement of the carriage assembly within the frame <NUM>, thereby preventing a user from accidentally initiating deployment of a prosthetic valve (<FIG>). Resheathing lock <NUM> may be coupled to the main body of the carriage assembly <NUM>. The resheathing lock <NUM> may include a laterally projecting pin <NUM> that is slidable within a hole in the main body of the carriage assembly. Pin <NUM> may have a first or unlocked condition in which it is compressed between main body <NUM> and frame <NUM>.

As the user rotates deployment actuator <NUM>, outer shaft <NUM> is pulled back and with it distal sheath <NUM> to uncover a portion of compartment <NUM>. This process may continue until a predetermined position just prior to a position at which resheathing is no longer possible. When this predetermined position is reached, a spring positioned in the hole between the main body of the carriage assembly and the pin <NUM> pushes the pin out through an aperture in frame <NUM> to a second or locked condition in which the pin protrudes from frame <NUM>, providing a visual indicator to the user that resheathing is no longer possible past this predetermined position. Further translation of the carriage assembly may be impeded until the user presses pin <NUM> to the interior of frame <NUM> against the action of spring <NUM> to confirm that further uncovering of compartment <NUM> is desired (i.e., that the user wishes to fully deploy the prosthetic heart valve in its current position).

The initial distance that the carriage assembly can travel before actuating resheathing lock <NUM> may depend on the structure and size of the particular prosthetic valve to be deployed. Preferably, the initial travel distance of the carriage assembly is about <NUM> to about <NUM> less than the length of the valve in the collapsed condition (e.g., about <NUM> to about <NUM> of the valve may remain covered to permit resheathing). Alternatively, the initial travel distance of the carriage assembly may be about <NUM> to about <NUM>, which is about <NUM>% to about <NUM>% of the length of an exemplary <NUM> valve. Thus, resheathing lock <NUM> may allow uncovering of compartment <NUM> up to a maximum distance or percentage, and allow further uncovering only after the user has pressed on laterally projecting pin <NUM> to confirm that additional release (e.g., full release of the prosthetic heart valve) is desired.

A second technique, referred to as a "coarse technique," may be used to cover and uncover compartment <NUM> more quickly and with less precision than the fine technique described above. Specifically, hub <NUM> may be coupled to the proximal end of inner shaft <NUM> and may be capable of moving the inner shaft relative to frame <NUM> to facilitate opening and closing of the compartment <NUM>. This coarse movement may be used when no prosthetic heart valve is present in the compartment, such as, for example, when the compartment is to be opened prior to loading the prosthetic heart valve, and when the compartment is to be closed after the valve has been fully deployed. A mechanical lock <NUM> may couple hub <NUM> to frame <NUM> to prevent accidental movement during use of operating handle <NUM>. For example, hub <NUM> and a portion of frame <NUM> may be threadedly engaged such that a rotation of the hub relative to the frame is required to release the hub from the frame. Other types of mechanical locks that will releasably couple hub <NUM> to frame <NUM> as intended will be known to those skilled in the art. After lock <NUM> has been disengaged, hub <NUM> may be used to quickly cover or uncover compartment <NUM>. Movement of inner shaft <NUM> with respect to outer shaft <NUM> may open and close the compartment. Thus, pushing hub <NUM> distally (and thus the distal movement of inner shaft <NUM>) opens compartment <NUM> and pulling hub <NUM> proximally closes the compartment.

Optionally, an indicator window <NUM> may be disposed on top of frame <NUM> and may include a series of increments showing a percent or extent of deployment of the prosthetic heart valve. A scrolling bar may move along window <NUM> past the series of increments as deployment continues to illustrate to the user the extent to which the prosthetic heart valve has been deployed. Scrolling bar indicates that a prosthetic heart valve is approximately <NUM>% deployed. Indicator window <NUM> further includes a critical indicator showing the position past which resheathing is no longer possible. Resheathing lock <NUM> may be activated as the scrolling bar, which is coupled to the main body of the carriage assembly reaches position the critical indicator position. Additional features of delivery devices that may be suitable for use in delivering a prosthetic valve similar to prosthetic valve <NUM> are described in <CIT>.

As noted above, although embolic protection devices have been used in interventional procedures, typically the use of such devices during a TAVR procedure increase complexity and the time required for the procedure. <FIG> illustrate a delivery device <NUM> that includes embolic protection features according to an aspect of the disclosure. Referring to <FIG>, a delivery device <NUM> is illustrated passing through the aortic arch as a collapsed prosthetic heart valve PHV is being advanced toward the native aortic valve. Prosthetic heart valve PHV may be any suitable collapsible and expandable prosthetic aortic heart valve, such as prosthetic heart valve <NUM>. Delivery device <NUM> may be substantially similar or identical to delivery device <NUM>, with certain modifications described below. However, it should be understood that the modifications may be applied to other prosthetic heart valve delivery devices that are not identical to delivery device <NUM>.

In use, the prosthetic heart valve PHV, held in a collapsed condition within delivery device <NUM>, is advanced to the native aortic valve annulus. Prior to deploying the prosthetic heart valve PHV, a filter <NUM> may be deployed from the delivery device <NUM> to cover the ostia of one or more of the arteries <NUM>, <NUM>, <NUM> extending from the aorta. In <FIG>, the filter <NUM> is illustrated as being maintained in a collapsed delivery condition by an overlying filter sheath <NUM>. When the prosthetic heart valve PHV is in the desired deployment position, but still maintained in a collapsed condition, filter sheath <NUM> may be retracted to allow filter <NUM> to transition to a deployed condition, as shown in <FIG>. Filter <NUM> may include a filter section <NUM> and a connection member <NUM>. The filter section <NUM> may be formed of a shape memory metal, including for example nitinol. The filter section <NUM> may be formed of a single component or multiple components. For example, the filter section <NUM> may be formed of a scaffold that includes a fabric or other material mounted to the scaffold. Otherwise, the filter section <NUM> may be formed of a single material, such as nitinol, braided together into a desired shape. However, it should be understood that various other metal and non-metal materials may be suitable to form filter section <NUM>. Regardless of the material forming the filter section <NUM>, or the particular structure of the filter section <NUM>, the filter section <NUM> preferably is porous enough to allow blood to flow through the filter section <NUM>, but not so porous as to allow debris, such as emboli, to pass through the filter section <NUM>. Thus, for example, if filter section <NUM> is formed of braided nitinol, the density of the braid should be low enough to allow blood to pass through the braid, but high enough to capture or deflect debris such as emboli. The filter section <NUM> may have any suitable shape that allows it to be compressed for delivery, and to cover the desired ostia of the arteries extending from the aorta. For example, as shown in <FIG>, the filter section <NUM> may be long and flat, such as having an elongated oval shape, so that in the deployed condition, the filter section covers the ostium of each artery <NUM>, <NUM>, <NUM> in the deployed condition. It should be understood that other shapes may be suitable. In addition, rather than being flat, the filter section <NUM> may include an amount of curvature to better conform to the curvature of the wall(s) of the aorta.

A proximal end of the filter section <NUM> may be coupled to the delivery device <NUM> via connection member <NUM>. In the illustrated embodiment, connection member <NUM> preferably takes the form of a thin arm, and preferably has enough rigidity to help the filter section <NUM> maintain its position relative to the point of connection to the delivery device <NUM> when deployed. In addition, an amount of rigidity of the connection member <NUM> may assist in guiding the filter section <NUM> back into a collapsed condition within the filter sheath <NUM> prior to removal of the delivery device <NUM> upon completion of the procedure. In some embodiments, connection member <NUM> may be a single metallic wire such as a nitinol wire, or a group of wires. The distal end of the connection member <NUM> may be integral with, or otherwise attached to, the filter section <NUM>. The proximal end of the connection member <NUM> may be coupled to any component of the delivery device <NUM> that is capable of maintaining a substantially static position relative to the aorta <NUM> while the outer sheath <NUM> is retracted for deployment of the prosthetic heart valve PHV. In the illustrated embodiment, the proximal end of the connection member <NUM> may be fixed to a portion of a stability layer, which may be similar or identical to the stability layer described in connection with delivery device <NUM>. Although the stability layer is not separately labeled in <FIG>, the stability layer is translationally fixed to a distal end portion of an operating handle, similar to operating handle <NUM>, and directly overlies the outer sheath <NUM>. The stability layer may extend distally from the operating handle to a location that is spaced proximally from the distal sheath that houses the prosthetic heart valve PHV, so that the outer sheath <NUM> may be retracted within stability layer to fully deploy the prosthetic heart valve PHV. However, in other embodiments, the proximal end of the connection member <NUM> may be coupled to other components of the delivery device <NUM>, such as by extending proximally, interior to filter sheath <NUM>, to the operating handle or other component.

With the prosthetic heart valve PHV in the collapsed condition and positioned within or adjacent the native aortic valve, filter sheath <NUM> may be retracted to deploy filter <NUM>. Filter sheath <NUM> may be similar or the same as introducer sheath <NUM> described in connection with delivery device <NUM>, or may be a separate sheath positioned outside of outer sheath <NUM> and inside of an introducer sheath similar to introducer sheath <NUM>, if such an introducer sheath is included in delivery device <NUM>. As the filter sheath <NUM> is retracted, the filter section <NUM> may begin to expand or otherwise transition from a delivery state (shown in <FIG>) to a deployed state (shown in <FIG>) in which the filter section <NUM> covers the ostia of one or more of the arteries <NUM>, <NUM>, <NUM> extending from the aorta. As the filter sheath <NUM> retracts so that it no longer overlies connection member <NUM>, the connection member <NUM> may help the filter section <NUM> spring, pop, or otherwise transition into the desired position. With the filter <NUM> deployed in the desired position, as shown in <FIG>, the outer sheath <NUM> may be retracted to deploy the prosthetic heart valve PHV into the native aortic valve annulus. The retraction of the outer sheath <NUM> does not substantially affect the position of the filter <NUM> relative to the ostia of the arteries <NUM>, <NUM>, <NUM>, at least because the connection member <NUM> is coupled to a component that does not translate as a result of retraction of the outer sheath <NUM>. During deployment of the prosthetic heart valve PHV, any tissue or other debris that may be dislodged and travel in the bloodstream through the aorta <NUM> is likely to be either trapped within the filter portion <NUM>, or deflected into the descending aorta, reducing the risk of stroke or TIA. Once the prosthetic heart valve PHV is implanted in a desired manner, the outer sheath <NUM> may be advanced to close the compartment that previously housed the prosthetic heart valve PHV. Alternatively, a hub similar to hub <NUM> of delivery device <NUM> may be pulled proximally to result in a "coarse" movement to close the capsule after the prosthetic heart valve PHV is fully deployed. Then, the filter sheath <NUM> may be advanced distally relative to the outer sheath <NUM> and/or the stability layer. The filter sheath <NUM> will ride along the connection member <NUM>, forcing the connection member to a position between the filter sheath <NUM> and the outer sheath <NUM> and/or the stability layer. As advancement of the filter sheath <NUM> continues, the filter portion <NUM>, along with any debris trapped therein, is also forced back into the collapsed condition within the filter sheath <NUM>, similar to the condition shown in <FIG>. Then, the delivery system <NUM> may be removed from the body, completing the procedure. As should be understood, compared to the use of a separate embolic protection device, the provision of the filter <NUM> on the delivery device <NUM> that also contains the prosthetic heart valve PHV may significantly reduce the complexity and time of the procedure.

<FIG> illustrate a delivery device <NUM> that includes embolic protection features according to another aspect of the disclosure. Referring to <FIG>, a delivery device <NUM> is illustrated passing through the aortic arch as a collapsed prosthetic heart valve PHV is being advanced toward the native aortic valve AV. Prosthetic heart valve PHV may be any suitable collapsible and expandable prosthetic aortic heart valve, such as prosthetic heart valve <NUM>. However, the prosthetic heart valve PHV in <FIG> may have slight construction differences to account for the fact that the prosthetic heart valve PHV is deployed by advancing an overlying sheath, instead of retracting an overlying sheath. For example, the prosthetic heart valve PHV of <FIG> may have retainers similar to retainers <NUM> to couple the prosthetic heart valve PHV to the delivery device <NUM>, but those retainers may be positioned on the outflow end of the device. Delivery device <NUM> may be substantially similar or identical to delivery device <NUM>, with certain modifications described below. However, it should be understood that the modifications may be applied to other prosthetic heart valve delivery devices that are not identical to delivery device <NUM>.

Delivery device <NUM> may include an outer sheath <NUM> generally similar to outer sheath <NUM>. Delivery device <NUM> may also include a distal sheath or capsule <NUM> that is generally similar to distal sheath <NUM>. However, while delivery device <NUM> releases the prosthetic heart valve <NUM> by retracting the outer sheath <NUM> which in turn retracts the distal sheath <NUM>, the distal sheath <NUM> of delivery device <NUM> is advanced distally to deploy the prosthetic heart valve PHV. This may be accomplished by any suitable means, for example, including an interior shaft being coupled to the distal tip of <NUM> of the delivery device <NUM>, with the distal tip <NUM> being connected or integral with the distal sheath <NUM>, such that advancement of the inner shaft advances both the distal tip <NUM> and the distal sheath <NUM>, as shown in <FIG>.

Referring back to <FIG>, the distal sheath <NUM> may have a length to house not only the prosthetic heart valve PHV in a collapsed condition, but also a filter <NUM> in a collapsed condition, the filter being positioned proximal to the prosthetic heart valve PHV in series. The delivery device <NUM> may be delivered through the aortic arch and into position within the native aortic valve AV. The inner shaft may be advanced, for example via actuating a wheel or slider on an operating handle outside the patient's body, to begin to advance the distal sheath <NUM> distally toward the left ventricle (not labeled). As the distal sheath <NUM> advances distally, the overlying constraint on the filter <NUM> is released, allowing the filter <NUM> to begin to transition from the collapsed condition into the expanded condition, as seen in <FIG>. Continued distal advancement of the distal sheath <NUM> releases the overlying constraint on the prosthetic heart valve PHV, allowing the prosthetic heart valve PHV to transition into the expanded condition after the filter <NUM> has been deployed downstream of the prosthetic heart valve PHV, as shown in <FIG>.

Referring still to <FIG>, both the filter <NUM> and the prosthetic heart valve PHV may overlie a middle shaft <NUM>. The filter <NUM> may include a proximal end, a distal end, and an intermediate portion between the proximal end and the distal end. The distal end of the filter <NUM> is preferably attached to the middle shaft <NUM>. The proximal end of the filter <NUM> may be unattached to the middle shaft <NUM>, and form a circular or tubular shape in the expanded condition, preferably with dimensions such that complete or substantially complete contact with an interior circumference of the aorta <NUM> is formed. In the illustrated embodiment, the intermediate portion of the filter <NUM> includes a substantially conical or frustoconical shape extending from the point of attachment to the middle shaft <NUM> toward the proximal end of the filter <NUM>. It should be understood that, although arteries <NUM>, <NUM>, <NUM> are not illustrated in <FIG>, in operation, the arteries <NUM>, <NUM>, <NUM> would all be positioned downstream of the filter <NUM> when the filter <NUM> is deployed. The filter <NUM> may be formed of any of the materials described above in connection with filter <NUM>, including a nitinol scaffold with fabric mounted to the scaffold, or braided nitinol, although various other filter materials and structures that allow blood to pass through but inhibit debris from passing through may be suitable. With this configuration, the sequential deployment of filter <NUM> prior to the deployment of the prosthetic heart valve PHV may have at least two benefits. First, because the filter <NUM> spans across an entire cross-sectional area of a plane of the aorta <NUM> transverse to the direction of blood flow in the deployed condition, any tissue or other debris entering the flow of blood from the following deployment of the prosthetic heart valve PHV. By trapping the debris within the filter <NUM> at a position upstream from the arteries <NUM>, <NUM>, <NUM> extending from the aorta, the debris is prevented from causing blockages downstream of the filter <NUM>. Second, the contact of the filter <NUM> with the interior wall of the aorta <NUM> may function to center the middle shaft <NUM> within the aorta <NUM>, which may help center the prosthetic heart valve PHV within the center of the annulus of the native aortic valve AV prior to deployment, which is generally desirable. Filter <NUM> may include additional features such as folds that create local divots, pockets, or valleys to reduce the likelihood that debris that gets trapped into filter <NUM> does not get dislodged or ejected back into the bloodstream as the distal sheath <NUM> collapses the filter <NUM> back into the collapsed or delivery condition.

After the prosthetic heart valve PHV is in the desired position, as shown in <FIG>, the distal sheath <NUM> may be retracted by retracting the inner shaft. As the distal sheath <NUM> retracts, it passes through the center of the deployed prosthetic heart valve PHV. As the proximal end of the distal sheath <NUM> approaches the distal end of the filter <NUM>, continued retraction of the distal sheath <NUM> forces the filter <NUM> to collapse back into the distal sheath <NUM>. This is possible, at least in part, because the distal end of the filter <NUM> is in contact with the middle shaft <NUM>, so that the distal end of the filter <NUM> acts as ramp or rail over which the proximal end of the distal sheath <NUM> may ride as it retracts. The distal sheath <NUM> may be retracted until the proximal end of the distal sheath <NUM> abuts the distal end of the outer sheath <NUM>, at which point the delivery device <NUM> may be removed from the patient. As should be understood, there are essentially no additional steps necessary to provide embolic protection in the embodiment of delivery device <NUM> compared to the steps that would be required to deliver the prosthetic heart valve PHV without the benefit of a filter that provides embolic protection.

<FIG> illustrates a delivery device <NUM> that includes embolic protection features according to another aspect of the disclosure. Referring to <FIG>, a delivery device <NUM> is illustrated passing through the aortic arch as a collapsed prosthetic heart valve PHV is being advanced toward the native aortic valve AV while being maintained in a collapsed condition in the distal sheath <NUM>. Prosthetic heart valve PHV may be any suitable collapsible and expandable prosthetic aortic heart valve, such as prosthetic heart valve <NUM>. Delivery device <NUM> may be substantially similar or identical to delivery device <NUM>, with certain modifications described below. However, it should be understood that the modifications may be applied to other prosthetic heart valve delivery devices that are not identical to delivery device <NUM>.

Still referring to <FIG>, delivery device <NUM> may include a filter 4200a positioned proximal to the distal sheath <NUM>. Filter 4200a may include a proximal end that is coupled to a stability layer <NUM> that may be similar to the stability layers described above, the outer shaft <NUM> being translatable with respect to the stability layer <NUM>. However, it should be understood that the proximal end of the filter 4200a may be directly or indirectly coupled to any component of the delivery device <NUM> that is capable of maintaining a substantially static position relative to the aorta <NUM> while the outer sheath <NUM> is retracted for deployment of the prosthetic heart valve PHV. This alternative option of connection of a filter to the stability layer may be true of other embodiment described herein as well. The distal end of filter 4200a may be unattached to the delivery device <NUM>. Filter 4200a may be formed of any of the structures and/or materials described above for other filters herein, preferably so that blood may flow through the filter 4200a but tissue or other debris are unable to flow through the filter 4200a. Although filter 4200a is illustrated as generally conical or frustoconical, tapering from an open distal end to an attached proximal end, other similar shapes may be suitable.

<FIG> is a perspective view of delivery device <NUM> with filter 4200a shown in an expanded or deployed state. It should be understood that the filter 4200a shown in <FIG> is shown with slight construction differences than the filter 4200a shown in <FIG>, although the overarching functional concepts are the same. For example, while the filter 4200a shown in <FIG> may be formed only of a metal or mesh such as a nitinol wire or braid without a separate fabric or membrane, the filter 4200a shown in <FIG> includes a metal scaffold or stent that is primarily used as a support for a fabric or membrane filter. As with the other delivery devices described herein, delivery device <NUM> may include an operating handle <NUM>, which may be similar or identical to operating handle <NUM> of delivery device <NUM>.

<FIG> is an enlarged view of delivery device <NUM> with filter 4200a in an expanded or deployed configuration, with a filter sheath <NUM> still overlying a proximal end of filter 4200a. Although filter sheath <NUM> may be similar to introducer sheath <NUM> of delivery device <NUM>, the filter sheath <NUM> may be a separate overlying sheath specifically for collapsing and deploying the filter 4200a. Although filter 4200a is generally represented as having a conical shape in <FIG>, the shape may be other than conical. For example, as shown in <FIG>, filter 4200a may include a framework of self-expanding materials with a porous fabric extending along and across the framework. Specifically, filter 4200a is shown in <FIG> as including a plurality of struts, which may be formed from nitinol, with the struts forming a single row of generally diamond-shaped cells 4202a. A fabric 4204a may cover each of the diamond-shaped cells 4202a, such that the fabric 4204a also has a generally diamond-shape for each cell 4202a. However, the fabric 4204a need not exactly follow the shape of the diamond-shaped cells 4202a. For example, the fabric may extend farther distally than is shown in <FIG> so that the fabric extends between distal peaks of adjacent diamond-shaped cells 4202a. The fabric 4204a may be formed of any suitable material that allows blood to pass through the fabric 4204a, but that does not allow larger particles of debris, such as tissue or emboli, from passing through the fabric 4204a. In one example, fabric 4204a may be a polyurethane material with pores that are laser cut into the material to achieve the desired porosity.

<FIG> illustrates the delivery device <NUM> after the filter sheath <NUM> has been withdrawn further proximally relative to the position shown in <FIG>. With the filter sheath <NUM> withdrawn further, the stability layer <NUM> becomes visible in <FIG>. The proximal end of filter 4200a may be coupled to stability layer <NUM> by any suitable connection. In the illustrated embodiment, struts at the proximal end of the filter 4200a are clamped or otherwise retained by a crimping member such as a crimp tube <NUM>. In other embodiments, the proximal end of the filter <NUM> may include retainers similar to retainers <NUM> of stent <NUM>, and complementary cut-outs or recesses may be provided in stability layer <NUM> or on a separate member, such as a stainless steel tube positioned on or adjacent the stability layer <NUM>, with an overlying member positioned radially outward of the recesses to maintain the retainers of the filter in the complementary recesses. Although the distal end of the filter 4200a has a zig-zag shape in the deployed condition as opposed to a continuous circular rim as shown in <FIG>, in the deployed condition shown in <FIG>, the fabric 4202a of the filter may create a complete ring around an inner circumference of the aorta <NUM> in a plane transverse to the direction of blood flow when the filter 4200a is fully deployed. The material forming the fabric 4204a may be formed onto the framework, for example by dipping or spraying.

Referring again to <FIG>, delivery device <NUM> may be advanced toward the native aortic valve AV so that the distal sheath <NUM>, with the prosthetic heart valve PHV maintained in a collapsed condition therein, is positioned within the annulus of the native aortic valve AV. During the delivery, the filter sheath <NUM> overlies the filter 4200a so that the filter is maintained in a collapsed condition. The relative spacing between the distal sheath <NUM> and the filter 4200a is preferably such that, when the distal sheath <NUM> is in the target implant location, withdrawing filter sheath <NUM> allows the filter 4200a to expand or otherwise transition to a deployed configuration in which the distal end of the filter 4200a is positioned upstream of the arteries <NUM>, <NUM>, <NUM> extending from the aorta <NUM>. Thus, prior to deploying the prosthetic heart valve PHV, the filter sheath <NUM> is retracted to allow the filter 4200a to transition to the deployed state, for example via self-expansion. With the filter 4200a in place, the outer sheath <NUM> may be withdrawn to withdraw the distal sheath <NUM> and to deploy the prosthetic heart valve PHV into the native aortic valve AV. As with other embodiments described herein, the outer sheath <NUM> may retract into the stability layer <NUM> so that the filter 4200a does not change position with respect to the arteries <NUM>, <NUM>, <NUM> while the distal sheath <NUM> is retracted. Due to the shape of the filter 4200a in the expanded or deployed condition, any debris or emboli that dislodge from the deployment of the prosthetic heart valve PHV is likely to enter the interior volume of the filter 4200a and become trapped therein. Once the prosthetic heart valve PHV is in the desired implanted position, the outer sheath <NUM> may be advanced to advance the distal sheath <NUM> into abutment with the distal tip of the delivery device. Alternatively, the nose cone may be retracted by using a hub similar to hub <NUM> of delivery device <NUM>. Then, the filter sheath <NUM> may be advanced relative to the filter to cause the filter to collapse back into the delivery condition, trapping any emboli or debris within the filter 4200a. The delivery device <NUM> may then be removed, completing the procedure and removing any trapped debris or emboli from the patient.

<FIG> is a highly schematic view of the delivery device <NUM> shown in essentially the same position as shown in <FIG>, with a first alternate filter 4200b used instead of filter 4200a. The functioning of filter 4200b with respect to delivery device <NUM> is essentially identical to the functioning of filter 4200a with respect to delivery device <NUM>. The main difference is that filter 4200b is formed of a braided material, such as braided nitinol. As with other embodiments disclosed herein, the braid density of filter 4200b may be dense enough so that tissue or other debris cannot pass through the filter 4200b, but not so dense as to prevent blood from passing through the filter 4200b. Alternately, the density of the braid may be small enough to allow for both blood and emboli to pass through, but a fabric or other material may be incorporated into or mounted on the braid to prevent the emboli from passing through the filter 4200b while allowing blood to pass through the filter 4200b. Preferably the filter 4200b is self-expandable and includes a proximal end coupled to the stability layer <NUM> and a distal end not directly attached to the delivery device <NUM>. In the expanded or deployed condition, the distal end of the filter 4200b may contact a continuous inner circumference of the aorta <NUM> so that blood, and any debris within the flow of blood, must pass through the open distal end of the filter 4200b. The filter 4200b may be generally conical or tubular in the expanded or deployed condition. As with filter 4200a, any emboli trapped within the filter 4200b may remain trapped within the filter 4200b when the filter sheath <NUM> is advanced to transition the filter 4200b back into the delivery or collapsed condition.

<FIG> is a highly schematic view of the delivery device <NUM> shown in essentially the same position as shown in <FIG>, with a second alternate filter 4200c used instead of filters 4200a or 4200b. The general functioning of filter 4200c with respect to delivery device <NUM> is essentially the same to the functioning of filters 4200a and 4200b with respect to delivery device <NUM>. The main difference is that filter 4200c is formed from a plurality of soft fibers that each have a first end coupled to the stability tube <NUM>, and extend radially outwardly away from the stability tube <NUM> to a second end that is sized to contact the inner wall of the aorta <NUM>. Filter 4200c preferably includes a plurality of fibers positioned along a length of the stability layer <NUM>, with fibers extending in multiple directions radially away from the stability layer <NUM>. The density of the fibers of the filter 4200c is preferably high enough to trap tissue or other embolic debris within the fibers of the filter 4200c, while not being so dense as to block blood from flowing through the filter 4200c. Although the fibers of the filter 4200c may be formed from many suitable materials, it is preferable that the material is soft enough so as to reduce risk of puncture or other damage to the inner wall of the aorta <NUM>. On the other hand, the material is preferably stiff enough or has shape-memory properties so as to allow the fibers to be collapsed when the filter sheath <NUM> is advanced distally of the filter 4200c, and to allow the fibers of the filter 4200c to spring or otherwise transition outwardly upon retraction of the filter sheath <NUM> so as to extend radially outwardly of the stability layer <NUM>. Materials that may be appropriate for forming the fibers may include polyethylene terephthalate (PET), polyurethane or liquid-crystal polymer (such as Vectran).

<FIG> is a highly schematic view of the delivery device <NUM> shown in essentially the same position as shown in <FIG>, with a third alternate filter 4200d used instead of filters 4200a-c. The functioning of filter 4200d with respect to delivery device <NUM> is essentially identical to the functioning of filters 4200a-c with respect to delivery device <NUM>. The main difference is that filter 4200d is formed of a braided material, such as braided nitinol, in the shape of a generally cylindrical disk. As with other embodiments disclosed herein, the braid density of filter 4200d may be dense enough so that tissue or other debris cannot pass through the filter 4200d, but not so dense as to prevent blood from passing through the filter 4200d. Alternately, the density of the braid may be low enough to allow for both blood and emboli to pass through, but a fabric or other material may be incorporated into or mounted on the braid to prevent the emboli from passing through the filter 4200d while allowing blood to pass through the filter 4200d. Preferably the filter 4200d is self-expandable. Rather than forming a conical type of shape with an open interior space, as with filter 4200b, the disk-shaped filter 4200d may have a cable or other connection member 4202d that had a distal end coupled to the filter 4200d, and a proximal end attached to stability layer <NUM>. In the expanded or deployed condition, the filter 4200d preferably has a size and shape to expand so as to occupy an entire cross-sectional interior area of the aorta <NUM> in a plane transverse the direction of blood flow. The disk-shaped filter 4200d may have a central aperture to allow outer sheath <NUM> to pass through the filter 4200d while the outer sheath <NUM> is retracted or advanced, with the central aperture having an inner diameter that is substantially the same or slightly larger than the outer diameter of the outer sheath <NUM>. In other embodiments, the disk-shaped filter 4200d may be directly coupled over the stability layer <NUM> so that the outer sheath <NUM> does not ride against an interior surface of the filter 4200d while the outer sheath <NUM> is retracted or advanced. Still further, while the illustrated embodiment shows that a proximal end of connection member 4202d is tied, crimped, or otherwise directly attached to stability layer <NUM>, in other embodiments, the connection member <NUM> may be a control wire with a proximal end that extends any desired distance proximally through the delivery device <NUM>, including to an operating handle. If connection member <NUM> is a control wire, it may be possible to retract the filter 4200d into the filter sheath <NUM> by pulling the control wire, for example by actuating the operating handle, proximally. As with filters 4200a-c, any emboli trapped within the filter 4200d may remain trapped within the filter 4200d when the filter 4200d is transitioned back into the collapsed or delivery condition within filter sheath <NUM>.

<FIG> illustrates a delivery device <NUM> that includes an embolic protection feature according to an aspect of the disclosure. The delivery device <NUM> is illustrated passing through the aortic arch as a collapsed prosthetic heart valve (not visible in <FIG>) is being advanced toward the native aortic valve while being maintained in a collapsed condition by distal sheath <NUM>. The prosthetic heart valve may be any suitable collapsible and expandable prosthetic aortic heart valve, such as prosthetic heart valve <NUM>. Delivery device <NUM> may be substantially similar or identical to delivery device <NUM>, with certain modifications described below. However, it should be understood that the modifications may be applied to other prosthetic heart valve delivery devices that are not identical to delivery device <NUM>.

A filter sheath <NUM> may be provided overlying the outer sheath <NUM>, the filter sheath being advanceable and retractable relative to the outer sheath <NUM>. Preferably, the embolic protection device includes three filters 5200a-c, with each filter 5200a-c being coupled to a distal end of a corresponding control wire 5202a-c, a proximal end of each control wire 5202a-c extending proximally within the filter sheath <NUM> to an operating handle that may be similar to operating handle <NUM>. Each filter 5200a-5200c may be formed of a braided material, such as a collapsible and expandable shape memory material like nitinol. Preferably, each filter 5200a-5200c is disk-shaped or plug-shaped generally similar to filter 4200d. However, each filter 5200a-5200c is preferably sized and shaped such that, in the expanded or deployed condition, each filter 5200a-5200c is able to occupy an entire cross-sectional area of a corresponding artery <NUM>, <NUM>, <NUM> in a plane transverse the direction of blood flow. As with the other filters described herein, filters 5200a-5200c are preferably configured to allow blood to pass through the filters 5200a-c, while restricting debris and other embolic debris from passing through the filters 5200a-c. Each filter 5200a-5200c may be tethered to a steerable control wire 5202a-5202c so that each filter 5200a-c can be individually steered into a corresponding artery <NUM>, <NUM>, <NUM>.

In an exemplary aortic heart valve replacement procedure, the prosthetic heart valve may be delivered to or near the native aortic valve similar to other methods described herein, with the filters 5200a-c each in a collapsed or delivery condition within the space between filter sheath <NUM> and outer sheath <NUM>. Prior to releasing any of the filters 5200a-c, it is preferable that the distal sheath <NUM> be positioned within or adjacent the annulus of the native aortic valve, although in other embodiments the filters 5200a-c may be positioned within the arteries <NUM>, <NUM>, <NUM> extending from the aorta <NUM> prior to positioning the distal sheath <NUM> within the annulus of the native aortic valve. With the distal sheath <NUM> in the desired position, one of the filters 5200a-c may be released from the filter sheath <NUM>. This may be achieved by retracting the filter sheath <NUM> proximal to the filter to be released, using the corresponding control wire to advance the filter distally to the filter sheath <NUM>, or a combination of both. The steerable control wire may be used, for example by manipulating a corresponding actuator on the operating handle, to guide the released filter into the desired artery. This process may be repeated two more times until each artery <NUM>, <NUM>, <NUM> has a corresponding filter 5200a-c in position within the artery. At this point, the outer sheath <NUM> and distal sheath <NUM> may be retracted to transition the prosthetic heart valve into the expanded state within the native aortic valve. Preferably, the retraction of the outer sheath <NUM> does not significantly interfere with any of the control wires 5202a-c attached to the filters 5200a-c. This may be achieved, for example, by including control wire lumens within filter sheath <NUM> so as to avoid direct contact between the outer sheath <NUM> and the control wires 5202a-c. Separate control wire lumens may not be necessary, however, and the control wires 5202a-c may simply remain positioned between the outer shaft <NUM> and the filter sheath <NUM>. If any tissue or embolic debris are dislodged during deployment of the prosthetic heart valve, the embolic debris may become trapped within one of the filters 5200a-c, or otherwise deflected and travel to the downstream aorta where the risk of strike or TIA due to the embolic debris is minimized or eliminated.

After the deployment of the prosthetic heart valve is completed, the filters 5200a-c may be pulled back into the filter sheath <NUM> by retracting the control wires 5202a-c. It is expected that the material forming the filters 5200a-c may be soft enough so that little or no damage occurs when pulling the filters 5200a-c out of the corresponding arteries 5200a-c. In order to minimize the distance that each filter 5200a-c needs to travel between the position within the corresponding artery <NUM>, <NUM>, <NUM> and the collapsed condition within the filter sheath <NUM>, the distal end of the filter sheath may be advanced to a position near the ostium of the artery in which the first filter to be retrieved is positioned. After the first filter is retrieved back into the filter sheath <NUM>, the filter sheath <NUM> may be repositioned so that its distal end is adjacent the ostium of the artery in which the next filter to be retrieved is positioned. The second filter may be pulled back into the filter sheath using the corresponding control wire. The process may be repeated for the final remaining filter, at which point the delivery device <NUM> may be removed from the patient to complete the procedure.

In some aspects, it may be useful to order the delivery and/or retrieval of the filters. For example, during the initial positioning of the filters, it may be preferable to first position the filter 5200a in artery <NUM>, then position filter 5200b in artery <NUM>, and finally position filter 5200c in artery <NUM>. It should be understood that the order of initial placement may be opposite the direction of blood flow. With this initial placement ordering, if placement of the filter dislodges any tissue or other embolic debris, the debris will likely flow in the direction of blood such that any debris dislodged from the first filter 5200a may pass into the descending aorta, any debris dislodged due to the second filter 5200b may be caught or deflected from artery <NUM> by filter 5200a, and any debris dislodged due to the third filter 5200c may be caught or deflected from arteries <NUM>, <NUM> by filters 5200a, 5200b. Similarly, it may be preferable to remove the filters 5200a-c in the opposite order after the prosthetic heart valve deployment is complete. The reasoning is substantially similar, in that any debris dislodged by the filter being removed (or dislodged from the filter if the debris is trapped in the filter) will be protected from entering the remaining arteries due to the downstream filters still being in place.

<FIG> illustrates a delivery device <NUM> that includes an embolic protection feature according to an aspect of the disclosure. The delivery device <NUM> is illustrated passing through the aortic arch as a collapsed prosthetic heart valve is being advanced toward the native aortic valve while being maintained in a collapsed condition by a distal sheath (not visible in <FIG>). The prosthetic heart valve may be any suitable collapsible and expandable prosthetic aortic heart valve, such as prosthetic heart valve <NUM>. Delivery device <NUM> may be substantially similar or identical to delivery device <NUM>, with certain modifications described below. However, it should be understood that the modifications may be applied to other prosthetic heart valve delivery devices that are not identical to delivery device <NUM>.

A filter sheath <NUM> may be provided overlying the outer sheath <NUM>, the filter sheath being advanceable and retractable relative to the outer sheath <NUM>. In this embodiment, the embolic protection device includes a fully releasable filter <NUM>. Filter <NUM> may be formed of any suitable material and structure described for the other filters herein. For example, filter <NUM> may be formed with a shape-memory metal that forms a lattice or similar framework onto which a fabric or other membrane is positioned so as to allow for blood to flow across the filter <NUM> but to prevent tissue or embolic debris from flowing across the filter. Alternately, filter <NUM> may be formed from a braided metal, such as a braided shape-memory metal like nitinol. The braid density may be high enough to allow blood, but not embolic debris, to pass through. Otherwise, the braid density may be low but the braid may include a fabric of other membrane within or mounted onto the braid density to provide the desired filtering effect.

Filter <NUM> is designed to be fully released from the filter sheath <NUM>. As a result, filter <NUM> preferably has a structure to allow the filter <NUM> to maintain a desired position within the aorta <NUM> and covering the ostia of the arteries <NUM>, <NUM>, <NUM>, while resisting any type of migration from typical forces such as from the flow of blood. One way to achieve this is to have a portion of the filter <NUM> have a tubular shape that, upon transition to the expanded or deployed state, creates enough friction with the interior wall of the aorta <NUM> to prevent accidental movement of the filter <NUM>. In the illustrated embodiment, the distal end of the filter <NUM> has the tubular structure to assist in maintaining the desired position within aorta <NUM>. As is described in greater detail below, the filter <NUM> is not to be left in the aorta <NUM> after completion of the prosthetic heart valve implantation, so it preferably has a mechanism to assist with removal of the filter <NUM> after completion of the procedure. In the illustrated embodiment, the structure (e.g. the nitinol scaffold or braids) is gathered together at a proximal end of the filter to create a mating feature <NUM>. It should be understood that the overall shape of filter <NUM> in the expanded or deployed condition maintains an interior passageway through the radial center of the filter <NUM>, so that only a relatively thin layer of filter <NUM> is pressed against the interior wall of the aorta <NUM>.

Still referring to <FIG>, with the prosthetic heart valve and distal sheath positioned in the desired location at or adjacent the annulus of the native heart valve, the filter sheath <NUM> may be retracted to fully release the filter <NUM> from the space between the filter sheath <NUM> and the outer sheath <NUM>. Preferably, upon release, the filter <NUM> covers all of the ostia of the arteries <NUM>, <NUM>, <NUM> extending from the aorta <NUM>, with the filter <NUM> exerting sufficient force radially outward onto the inner wall of the aorta <NUM> to keep the filter <NUM> in the desired position. With the filter <NUM> in the desired illustrated position, the prosthetic heart valve may be deployed into the annulus of the native aortic valve, and any tissue or embolic debris that becomes dislodged in the process will be deflected away from the ostia of the arteries <NUM>, <NUM>, <NUM> by virtue of the filter <NUM>. With the prosthetic heart valve deployment complete, the outer sheath <NUM> may be retracted into the filter sheath <NUM>.

In order to retrieve the filter <NUM>, a filter retrieval member <NUM> may be provided on an outer surface of a component of the delivery device <NUM> that will retract into the filter sheath <NUM>. In the illustrated example, the retrieval member <NUM> may be a magnet, and a corresponding magnet may be provided on the mating feature <NUM> at the gathered end of the filter <NUM>. As the magnetic retrieval member <NUM> passes the magnetic mating feature <NUM>, the magnets will attract and further retraction of the outer sheath <NUM> will pull the filter <NUM> into the filter sheath <NUM>. If any embolic debris has been captured within the filter <NUM>, the embolic debris will also be pulled into the filter sheath <NUM>, and the delivery device <NUM> may be removed from the body to complete the procedure. If the retrieval member <NUM> and the mating feature <NUM> take the form of magnets, one or both of the magnets may be provided as an electromagnet so that the magnets may be selectively turned on and off to avoid unintentional engagement of the magnets. However, it should be understood that the retrieval member <NUM> and the mating feature <NUM> may have other suitable corresponding designs to assist in the retrieval of the filter <NUM>. For example, the mating feature <NUM> may form a ring, snare, or a loop, and the retrieval member <NUM> may form a hook or grasper to couple to the mating feature. As should be understood, the mating feature <NUM> may form the hook or grasper, with the retrieval member <NUM> forming the ring, snare, or loop. Any other suitable mating mechanisms may be used to allow the outer sheath <NUM> to connect with the filter <NUM> and draw the filter <NUM> back into the filter sheath <NUM> as the outer sheath <NUM> is withdrawn into the filter sheath <NUM>.

Claim 1:
A delivery device (<NUM>) for a collapsible and expandable prosthetic heart valve (<NUM>), the delivery device comprising:
an outer sheath (<NUM>) extending from a proximal end to a distal end;
a delivery sheath (<NUM>) positioned at the distal end of the outer sheath, the delivery sheath being sized and shaped to maintain the prosthetic heart valve in a collapsed condition therein; and
a filter sheath (<NUM>) overlying a portion of the outer sheath;
characterised in that the delivery device includes an intermediate sheath (<NUM>) positioned between the outer sheath and the filter sheath; and
an embolic filter (4200a, 4200b, 4200c, 4200d) having a proximal end coupled to the intermediate sheath, and a distal end that is not directly attached to the intermediate sheath,
wherein the embolic filter has a delivery condition in which the filter sheath overlies the embolic filter and the distal end of the embolic filter is in a collapsed condition, and a deployed condition in which the filter sheath does not overlie the embolic filter and the distal end of the embolic filter is in an expanded condition.