Patent Description:
There are four arteries that carry oxygenated blood to the brain, i.e., the right and left vertebral arteries, and the right and left common carotid arteries. Various procedures conducted on the human body, e.g., TAVR, aortic valve valvuloplasty, carotid artery stenting, closure of the left atrial appendage, mitral valve annuloplasty, mitral valve replacement, mitral valve repair, TEVAR, etc. can cause and/or dislodge native or foreign materials, which dislodged bodies can travel into one or more of the cerebral arteries resulting in, inter alia, stroke. Therefore, filtering the innominate artery, right subclavian artery, right brachiocephalic artery, right common carotid artery, left vertebral artery, and left subclavian artery at aortic branch arches or at the arches of said arteries may be useful to prevent dislodged materials from migrating to the cerebral area.

Thromboembolic disorders, such as stroke, pulmonary embolism, peripheral thrombosis, atherosclerosis, and the like affect many people. These disorders are a major cause of morbidity and mortality in the United States and throughout the world. Thromboembolic events are characterized by an occlusion of a blood vessel. The occlusion can be caused by a clot, which is viscoelastic or jelly-like and comprises platelets, fibrinogen, and other clotting proteins.

Percutaneous aortic valve replacement procedures have become popular, but stroke rates related to this procedure are between two and twenty percent. During catheter delivery and valve implantation, plaque, calcium or other material may be dislodged from the vasculature and may travel through the carotid circulation and into the brain. When an artery is occluded by a clot or other embolic material, tissue ischemia develops from a lack of oxygen and nutrients. The ischemia progresses to tissue infarction or cell death if the occlusion persists. Infarction does not develop or is greatly limited if the flow of blood is reestablished rapidly. Failure to reestablish blood-flow can lead to the loss of limb, angina pectoris, myocardial infarction, stroke, or even death.

<CIT> relates to a vessel protector system including an outer sheath, an inner tube disposed within the outer sheath and moveable in a longitudinal direction relative to the outer sheath. Furthermore, the system includes at least one protector coupled to the inner tube, each of the at least one protector having a body formed from a filtering material and extending between a leading end and trailing end coupled to the inner tube. The body has a collapsed configuration and an expanded configuration.

Reestablishing blood flow and removal of the thrombus is highly desirable. Surgical techniques and medicaments to remove or dissolve obstructing material have been developed, but exposing a subject to surgery may be traumatic and is best avoided when possible. Additionally, the use of certain devices carry risks such as the risk of dislodging foreign bodies, damaging the interior lining of the vessel as the catheter is being manipulated, blood thinning, etc..

The present disclosure relates to a protection system as defined in claim <NUM>. The dependent claims define preferred embodiments of the protection system.

According to an aspect of the present disclosure, a protection system for preventing embolic material from entering the cerebral vasculature comprises an articulating distal sheath, a first or proximal filter, a second or secondary distal filter connected to the first filter by a first linking or tethering portion, and a third or distal filter connected to the second filter by a second linking or tethering portion. Each of the first filter, the second filter, and the third filter is configured to be deployed from the articulating distal sheath. When collapsed in the articulating distal sheath, an apex of each of the first filter, the second filter, and the third filter, is oriented distally of an open end of the respective filter. The first tethering portion can be sufficiently flexible to extend from the first vessel to the second vessel. The second tethering portion can be sufficient flexible to extend from the second vessel to the third vessel.

The present disclosure and its various embodiments can provide compound systems of filters and/or deflectors for collecting and/or deflecting debris in a manner such that all four cerebral arteries are protected. Embodiments of the present disclosure addresses debris, tissue, or the like, that can be dislodged during an endovascular procedure, travel into the cerebral vasculature, and embolize, leading to stroke or ischemia in an artery occluded, partially or totally, by the clot. For example, during a transcatheter aortic valve replacement (TAVR), stenotic material around the valve can be dislodged during implantation of the artificial valve. Moreover, atheromas and calcium along and within the aorta and aortic arch can be dislodged as the TAVR catheter is advanced toward the diseased aortic valve and subsequently withdrawn after implantation is completed. In addition, pieces of the catheter itself can be stripped away during delivery and implantation. These various forms of vascular debris, whether native or foreign, can then travel into one or more cerebral arteries, embolize, and cause a stroke or strokes.

Embodiments of the present disclosure are intended to address these potentially devastating cerebral events by providing a delivery system comprised of filters and/or deflectors and/or a combinations thereof, to intercept this debris before it can enter any of the cerebral arteries.

For reference, certain aspects of the disclosure may be directed toward a method of preventing embolic material from entering the cerebral vasculature. The method can include introducing a protection system into an aortic arch. The protection system can include an outer sheath, a distal filter portion, and a deflector portion having a first lobe and a second lobe. The method can also include deploying the distal filter portion in a first vessel and deploying the deflector portion in the aortic arch such that the first lobe prevents debris from flowing into a second vessel and the second lobe prevents debris from flowing into a third vessel. After deploying the distal filter portion and the deflector portion, the distal filter portion is distal to the deflector portion.

For reference, a protection system for use with the above-described method can include an outer sheath, an articulating distal sheath positioned radially inward of the outer sheath, a filter wire positioned radially inward of the articulating distal sheath, a distal filter portion carried by the filter wire, and a deflector portion positioned radially between the outer sheath and the articulating distal sheath in a pre-deployment configuration. The deflector portion can include a first lobe configured to seal against an ostium of a second vessel and a second lobe configured to seal against an ostium of a third vessel. In a post-deployment configuration, the distal filter portion is positioned distal to the deflector portion.

For reference, another method of preventing embolic material from entering the cerebral vasculature can include introducing a protection system into an aortic arch. The protection system can include an articulating distal sheath, a first or proximal filter, a second or secondary distal filter connected to the first filter by a first linking or tethering portion, and a third or distal filter connected to the second filter by a second linking or tethering portion. Each of the first filter, the second filter, and the third filter can be configured to be deployed from the articulating distal sheath. The method can also include deploying the first filter in a first vessel, then deploying the second filter in a second vessel, and then deploying the third filter in a third vessel.

Any feature, structure, or step disclosed herein can be replaced with or combined with any other feature, structure, or step disclosed herein, or omitted. Further, for purposes of summarizing the disclosure, certain aspects, advantages, and features of the inventions have been described herein. It is to be understood that not necessarily any or all such advantages are achieved in accordance with any particular embodiment of the inventions disclosed herein. No individual aspects of this disclosure are essential or indispensable.

Various embodiments are depicted in the accompanying drawings for illustrative purposes, and should in no way be interpreted as limiting the scope of the embodiments. Furthermore, various features of different disclosed embodiments can be combined to form additional embodiments, which are part of this disclosure.

The disclosure generally relates to devices and methods for filtering fluids and/or deflecting debris contained within fluids, including body fluids such as blood. A filtering or deflecting device can be positioned in an artery before and/or during an endovascular procedure, for example transcatheter aortic valve implantation (TAVI) or replacement (TAVR), transcatheter mitral valve implantation or repair (TMVR), surgical aortic valve replacement (SAVR), other surgical valve repair, implantation, or replacement, cardiac ablation (e.g., ablation of the pulmonary vein to treat atrial fibrillation) using a variety of energy modalities (e.g., radio frequency (RF), energy, cryo, microwave, ultrasound), cardiac bypass surgery (e.g., open-heart, percutaneous), transthoracic graft placement around the aortic arch, valvuloplasty, etc., to inhibit or prevent embolic material such as debris, emboli, thrombi, etc. resulting from entering the cerebral vasculature.

The devices may be used to trap particles in other blood vessels within a subject, and they can also be used outside of the vasculature. The devices described herein are generally adapted to be delivered percutaneously to a target location within a subject, but can be delivered in any suitable way and need not be limited to minimally-invasive procedures.

<FIG> is a schematic perspective view of an aortic arch <NUM>. The aortic arch <NUM> is upstream of the left and right coronary arteries (both not shown). The aortic arch <NUM> typically includes three great branch arteries: the brachiocephalic artery or innominate artery <NUM>, the left common carotid artery <NUM>, and the left subclavian artery <NUM>. The innominate artery <NUM> branches to the right common carotid artery <NUM>, then the right vertebral artery <NUM>, and thereafter is the right subclavian artery <NUM>. The right subclavian artery <NUM> supplies blood to, and may be directly accessed from (termed right radial access), the right arm. The left subclavian artery <NUM> branches to the left vertebral artery <NUM>, usually in the shoulder area. The left subclavian artery <NUM> supplies blood to, and may be directly accessed from (termed left radial access), the left arm. The aortic arch <NUM> may be reached from the femoral artery (not shown).

Devices and methods, some of which are compatible and/or synergistic with the devices and methods described herein, have been developed to filter blood flowing to the innominate artery <NUM> and the left common carotid artery <NUM>, which provide about <NUM>% of the blood entering the cerebral vasculature. Examples are provided in <CIT>. Certain such devices and methods leave the left subclavian artery <NUM>, and thus the left vertebral artery <NUM>, which provides about <NUM>% of the blood entering the cerebral vasculature, exposed to potential embolic material.

It may be preferred to achieve protection of all cerebral vessels from one access point. The present application discloses several single-access multi-vessel embodiments that can provide full cerebral protection with minimal arch interference.

<FIG> illustrates an example of a protection system <NUM> that can be inserted through a single access point from the right radial or brachial artery. The outer catheter <NUM> may have a diameter no greater than about 7F (<NUM> inches) or no greater than about 6F (<NUM> inches). The smaller diameter reduces possible complications associated with advancing the filter assembly through the vasculature.

The protection system <NUM> can include a proximal filter <NUM>, a distal filter <NUM>, and a deflector <NUM> configured to be deployed therebetween. The proximal filter <NUM> can be deployed in the brachiocephalic trunk <NUM>. The left subclavian artery <NUM> can be cannulated with an independently steerable and positionable (e.g., rotatable and/or translatable) articulating distal sheath <NUM>. A guidewire <NUM> can be utilized to facilitate positioning, and to interrogate (e.g., visualize and assist in positioning) the vessel during cannulation. A distal filter <NUM> can be deployed, e.g., by advancing the distal filter <NUM> or withdrawing the articulating distal sheath <NUM>, in the left subclavian artery <NUM>. The mechanisms for deploying the distal filter <NUM> and the proximal filter <NUM> can include features of the devices described in <CIT>. As shown in <FIG>, the articulating distal sheath <NUM> can include a deflector <NUM> that can protect the ostium of the left common carotid artery <NUM>. The deflector <NUM> can be mounted on or contained in the articulating distal sheath <NUM>, or the deflector <NUM> can be separately deployable from the articulating distal sheath <NUM>. Removal of the device can be accomplished as a reversal of the deployment steps into the outer catheter <NUM>.

The filters <NUM>, <NUM> and the deflector <NUM> may be deployed in any order. In a modified method, the device <NUM> can be introduced into the left radial or brachial artery. A first filter <NUM> can be deployed in the left subclavian artery <NUM> between the left vertebral branch <NUM> and the ostium of the aortic arch <NUM>. A second filter <NUM> can be deployed in the brachiocephalic trunk <NUM>, and a deflector <NUM> can be deployed to cover the ostium of the left common carotid artery <NUM>.

As shown in <FIG>, a protection system <NUM> can be used to protect all three vessels. A distal filter <NUM> can be configured to protect the left subclavian <NUM>, the proximal filter <NUM> can be left in the brachiocephalic artery <NUM>, and in certain arrangements, a deflector <NUM> can be added between the distal <NUM> and proximal filter <NUM> to protect the left common carotid artery <NUM>. The mechanisms for deploying the proximal filter <NUM> and the distal filter <NUM> can include any features of the filter systems described in <CIT>. Unlike the protection system <NUM> shown in <FIG>, the protection system can include a knuckle <NUM> located between the deflector <NUM> and the proximal filter <NUM>. The knuckle <NUM> is movable, maneuverable, or otherwise steerable, which can help create a tight bend to properly support and position the deflector <NUM>.

In one arrangement, the proximal filter <NUM> can be the largest filter and deployed in the proximal location when approaching from the right radial artery. This can be followed by deployment of the deflector <NUM> and the distal filter <NUM> distal of the proximal filter <NUM>. The mechanisms to deploy the filters, to deflect the articulating sheath for cannulation, and to additionally deploy the deflector can utilize any of the mechanisms described in <CIT>. In other methods, the deflector <NUM> and/or the distal filter <NUM> may be deployed prior to the proximal filter <NUM>.

<FIG> illustrate the various components of the protection system <NUM> shown in <FIG>. As shown in <FIG>, the protection system <NUM> can optionally include a skeleton portion <NUM>. The length between the knuckle <NUM> and the skeleton portion <NUM> of the articulating distal sheath <NUM> can be adjusted using one or more pull-wires. The knuckle <NUM> and the skeleton portion <NUM> can be two separate components that move relative to each other or part of a single component sufficiently flexible to bend when pulled toward each other. For example, a distal end of one pull wire can be connected to the knuckle <NUM> and a distal end of another pull wire can be connected to the skeleton portion <NUM>. The region between the knuckle <NUM> and the skeleton portion <NUM> can be foreshortened to properly position the deflector <NUM> against the vessel wall. The skeleton portion <NUM> can be a laser cut, thin-walled tube that is designed to bend before any other portion of the articulating distal sheath <NUM>.

Each end of the deflector <NUM> may be mounted to the articulating distal sheath <NUM> such that the deflector <NUM> is free to deflect. The deflector <NUM> can be rotated, translated, and/or apposed to the roof of the aortic arch <NUM> by pulling against either the deflected articulating distal sheath <NUM> or the deployed distal filter <NUM>. <FIG> shows a cross section of the device through line 2D-2D in <FIG> that shows the device <NUM> can include an outer sheath <NUM>, a core shaft <NUM> supporting the proximal filter <NUM> and positioned radially inward of the outer sheath <NUM>, a pull wire <NUM> for controlling the articulating distal sheath <NUM>, an inner member <NUM> supporting the distal filter <NUM>, and/or a guidewire <NUM> extending through the inner member <NUM>. A lumen space <NUM> between the outer sheath <NUM> and the core shaft <NUM> can provide space for the proximal filter <NUM> and the deflector <NUM>.

The handle <NUM> shown in <FIG> can include a distal filter actuator <NUM>. For example, the distal filter actuator <NUM> can be advanced or withdrawn to control a position of the distal filter <NUM>, as indicated by the arrows near the distal filter slider actuator <NUM> in <FIG>. Distal to the distal filter actuator <NUM>, the handle <NUM> can include a port <NUM> for flushing fluids. Distal to the port <NUM>, the handle <NUM> can include an actuation mechanism <NUM> for articulating the articulating distal sheath <NUM> (as shown by the arrows near actuation mechanism <NUM>). The actuation mechanism <NUM> can include a screw drive mechanism to deflect the articulating distal sheath <NUM> by rotating the actuation mechanism <NUM>. The screw drive mechanism can be self-locking to prevent unintentional deflection of the articulating distal sheath <NUM>. The rear portion <NUM> (outlined in the dashed box) of the handle <NUM> can be translated to move the articulating distal sheath <NUM>, deflector <NUM>, and/or distal filter <NUM>. Distal to the actuation mechanism <NUM>, the handle <NUM> can include an additional flush port <NUM>. Distal to the flush port <NUM>, the handle <NUM> can include an actuation mechanism <NUM>, for example a slider, to retract and advance the outer sheath <NUM> (as shown by the arrows near actuation mechanism <NUM>), which releases and retrieves the proximal filter <NUM>. Each of these actuation mechanisms
<NUM>, <NUM>, <NUM> can be sequentially positioned along the handle <NUM> according to how the procedure is performed, but the actuation mechanisms <NUM>, <NUM>, <NUM> can take on different configurations or be positioned in a different order.

As shown <FIG>, a challenge with deflectors is opposing the deflector <NUM> against the target vessel and avoiding interference with the index procedure. In order to properly seal against the target vessel, a force can be provided to conform the deflector to the vessel wall. The deflectors can push off the wall opposite the target vessel location, compressing the deflector into place. However, this creates a risk of interfering with the other procedures.

An alternative is to conform the deflector by pulling it up with tension. For example, <FIG> illustrate three different methods of conforming the deflector <NUM> to the vessel wall. These methods can be used independently or in combination with each other. As shown in <FIG>, an articulating distal sheath <NUM> can be used to properly orient the deflector <NUM>. With such an articulating sheath <NUM>, the left subclavian <NUM> can be cannulated and hooked allowing for the whole system <NUM> to be pulled back against the hooked distal end of the articulating distal sheath <NUM>. This may apply tension between the proximal filter <NUM> in the brachiocephalic artery <NUM> and the hooked end of the articulating distal sheath <NUM>, pulling the intermediate section of the articulating distal sheath <NUM> up against the roof of the aortic arch <NUM> and the left common carotid artery <NUM>.

<FIG> shows another method using a filter frame anchor <NUM>. In this configuration, the distal filter <NUM> may include a filter frame anchor <NUM> to provide more surface area to contact the wall of the left subclavian artery <NUM>. This may provide a similar mechanism to the design described in <FIG>, allowing for the system <NUM> to be pulled back against the filter frame anchor <NUM> and pulling the intermediate section of the articulating distal sheath <NUM> or other sheath up against the roof of the aortic arch <NUM>.

As described above, the articulating sheath <NUM> can be actuated by pulling on a pull wire <NUM> that is attached to the distal end of the articulating distal sheath <NUM>. This pull wire <NUM> is impeded off the central axis causing the sheath to deflect as the wire foreshortens. A similar mechanism may be employed in the deflector itself <NUM>, as shown in <FIG>. By attaching pullwire(s) <NUM> off-axis to the deflector <NUM>, the deflector's curvature and tilt may be controlled. Further details and embodiments of such a deflector <NUM> with a pull wire <NUM> are illustrated in <FIG>.

As shown in <FIG>, one or more pull wires <NUM> can extend through the deflector <NUM>. The one or more pull wires <NUM> can be fixed to a distal end of the deflector <NUM>. In <FIG>, as the pull wire(s) <NUM> are pulled proximally, the curvature of the deflector <NUM> increases. <FIG> shows an end view of the deflector <NUM>. Selectively pulling the pull wires <NUM> will tilt the deflector <NUM> off-axis as shown by the dashed lines.

<FIG> illustrates a deflector design that can be used with any of the example systems described herein. The deflector <NUM> self-locates based on the shape of the deflector <NUM>. For example, the deflector <NUM> can include a flexible dome shaped portion <NUM>, such as in a central region of the deflector <NUM> where the diameter decreases toward the apex of the dome shaped portion <NUM>. An apex of the dome shaped portion <NUM> can have a diameter of less than or equal to half of a diameter of a base of the dome shaped portion <NUM>. For example, a base of the dome shaped portion <NUM> can have about a <NUM> diameter and an apex of the dome shaped portion <NUM> can have about a <NUM> diameter. The deflector <NUM> may seal against the vessel opening rather than the area around the vessel. In addition, this may provide position location feedback when attempting to place the deflector in the correct location.

<NUM>-<NUM> illustrate another example protection system <NUM> with a deflector <NUM> that engages a greater surface area of a roof of the aortic arch <NUM>. In this example, as shown in <FIG>, the deflector <NUM> can have one or both ends mounted to a slideable collar <NUM>. The deflector <NUM> can be configured such that blood pressure can push the deflector <NUM> into the left common carotid <NUM> as shown in <FIG>. Additionally or alternatively, the slideable collar(s) <NUM> can be coupled to one or more pull wires (not shown) to foreshorten the deflector <NUM> and push the deflector <NUM> into the left common carotid <NUM> as shown in FIG.

With reference to <FIG>, another illustrative embodiment of a protection system <NUM> is shown. The protection system <NUM> resembles the protection system <NUM> discussed above in many respects. Accordingly, numerals used to identify features of the protection system <NUM> are incremented by a factor of one hundred (<NUM>) to identify like features of the protection system <NUM>. This numbering convention generally applies to the remainder of the figures. Any component or step disclosed in any embodiment in this specification can be used in other embodiments.

<FIG> illustrates yet another example protection system <NUM> in which two filters <NUM>, <NUM> are serially loaded into the articulating distal sheath <NUM> that can be delivered to the aorta <NUM> via an outer sheath <NUM>. As shown in <FIG>, the distal filter <NUM> and the secondary distal filter <NUM> can be loaded in the articulating distal sheath <NUM>.

As shown in <FIG>, the proximal filter <NUM> can be placed in the brachiocephalic trunk <NUM>. The articulating distal sheath <NUM> can be rotated, advanced/retracted, and/or articulated in order to allow for cannulation of a second and/or third vessel. The protection system <NUM> can utilize certain features such as the articulating sheath described in <CIT>, to place the secondary distal filter <NUM> in the left common carotid artery <NUM> and/or the distal filter <NUM> in the left subclavian artery <NUM>. A first vessel can be cannulated, preferably the left subclavian artery <NUM>, and the distal filter <NUM> can be deployed in the first vessel. This distal filter <NUM> can be detached from the articulating distal sheath <NUM> for later retrieval. Following placement of the distal filter <NUM>, the tip of the articulating distal sheath <NUM> can be withdrawn, and the second vessel, preferably the left common carotid artery <NUM>, can be cannulated, and a secondary distal filter <NUM> can be deployed in the second vessel. In order to remove the system, the secondary distal filter <NUM> can be first resheathed, and then a feature <NUM> on the detachable distal filter <NUM> can be recaptured by the articulating distal sheath <NUM>. The proximal filter <NUM> that was placed in the brachiocephalic trunk <NUM> can be resheathed and the protection system <NUM> can be removed from the body.

In other configurations, the detachable distal filter <NUM> can be placed in the left common carotid artery <NUM>, and the second filter <NUM> can be placed in the left subclavian artery <NUM>. Instead of the right radial or brachial artery, the protection system <NUM> can also be inserted into the body through the left radial or brachial artery.

<FIG> illustrate another example protection system <NUM>. Prior to deployment, the distal filter <NUM> and the secondary distal filter <NUM> can be loaded in the articulating distal sheath <NUM>, as shown in <FIG>. A proximal filter <NUM> can be deployed in the brachiocephalic trunk <NUM>. The left subclavian artery <NUM> can be cannulated with an independently steerable and positionable (e.g., rotatable and/or translatable) articulating distal sheath <NUM>. A guidewire (not shown) can be utilized to facilitate positioning and to interrogate (e.g., visualize and assist in positioning) the vessel during cannulation.

A distal filter <NUM> can be deployed (e.g., by advancing the distal filter <NUM> or withdrawing the articulating distal sheath <NUM>) in the left subclavian artery <NUM>. The system <NUM> can utilize any of the features, such as the articulating sheath <NUM> described in <CIT>. Alternatively, the distal filter <NUM> can be placed in the left common carotid artery <NUM>. The distal filter <NUM> can be connected to the articulating distal sheath <NUM> and/or the secondary distal filter <NUM> (still inside the tip of the articulating distal sheath <NUM>) with a flexible tether <NUM>. The flexible tether <NUM> can include a wire, an elastomeric material, nylon filament, suture, or other conformable attachment method.

Following placement of the first distal filter <NUM> in the left subclavian artery <NUM>, the articulating distal sheath <NUM> can be withdrawn, and the second vessel, preferably the left common carotid artery <NUM>, can be cannulated, so the secondary distal filter <NUM> can be deployed in the second vessel. The slack in the tether <NUM> may be pulled up against the vessel carina between the left common carotid artery <NUM> and the left subclavian <NUM> during deployment of the secondary distal filter <NUM> in the left common carotid artery <NUM>.

In order to remove the system <NUM>, the secondary distal filter <NUM> can be first resheathed, and then the distal filter <NUM> can be resheathed by withdrawing the tether <NUM> in order to pull the filter <NUM> into the tip of the articulating distal sheath <NUM>. The proximal filter <NUM> that was placed in the brachiocephalic trunk <NUM> can be resheathed and the device <NUM> removed from the body. Alternatively, the distal filter <NUM> can be placed in the left common carotid artery <NUM>, and then the secondary distal filter <NUM> can be placed in the left subclavian artery <NUM>. Instead of the right radial or brachial artery, the protection system <NUM> can also be inserted into the body through the left radial or brachial artery.

<FIG> illustrate a protection system <NUM> according to an aspect of the present disclosure, in which three sequential filters <NUM>, <NUM>, <NUM> can be collapsed and loaded into a common delivery sheath <NUM>. Because the protection system <NUM> is delivered through the femoral artery, the system <NUM> can be sized up to at least <NUM> Fr or greater and only uses only two access sites for the TAVR procedure. In some implementations, a pigtail catheter for the index procedure can be integrated or incorporated into the example protection system <NUM>, such that the pigtail catheter and the filters <NUM>, <NUM>, <NUM> are delivered from the same access site. The pigtail catheter can be delivered through the same sheath or introducer as the filters <NUM>, <NUM>, <NUM>. Further, the protection system <NUM> does not require retroflex cannulation. Although <FIG> illustrates the system <NUM> being delivered through the femoral artery, the system <NUM> can also be delivered via the right arm (e.g. right radial artery) or the left arm (e.g. left radial artery). The sizing and orientation of the filters would match the vessel diameters. For instance, in a femoral artery configuration, the apex of each filter shall be distal relative to the operator.

The proximal filter <NUM> may be delivered to the brachiocephalic artery <NUM>, followed in order with the secondary distal filter <NUM> being delivered to the left common carotid artery <NUM>, and the distal filter <NUM> being delivered to the left subclavian artery <NUM>. A diameter of each filter opening would be approximately <NUM> - <NUM> for the brachiocephalic artery <NUM>, <NUM> -<NUM> for the left common carotid artery <NUM>, and <NUM> - <NUM> for the right subclavian artery <NUM>. The filters <NUM>, <NUM>, <NUM> can be joined together by one or more tethering elements <NUM>, <NUM>. The tethering elements <NUM>, <NUM> may form a continuous tether. The tethering elements <NUM>, <NUM> can extend through a coaxial shaft <NUM>. Alternatively, each filter <NUM>, <NUM>, <NUM> can include a filter frame supporting a filter membrane, and the tethering elements <NUM>, <NUM> may be integrated into the filter frame and run within the filter membrane of one or more filters <NUM>, <NUM>, <NUM>. The tethering elements <NUM>, <NUM> may be elastomeric or elastomeric with a core that becomes axially rigid at a specified elongation. Alternatively, the tethering elements <NUM>, <NUM> may comprise a wire, nylon filament, suture material, or other conformable material. The relative length and/or elasticity shall ensure that the tethering elements <NUM>, <NUM> have sufficient tension to draw the tethering elements <NUM>, <NUM> up against the vessel carina in order to minimize possible entanglement or interference with other procedural devices, e.g., diagnostic catheters, guidewires, TAVI delivery systems, etc..

<FIG> illustrates another example protection system <NUM> having an aortic deflector <NUM>. The deflector <NUM> can be mounted to the catheter shaft <NUM> using a pull wire, tether, or other structure. The deflector <NUM> can have a through-hole through which an articulating distal sheath <NUM> can be advanced. Deploying the distal filter <NUM> through the deflector <NUM> can be more advantageous than deploying the deflector <NUM> through a filter because the larger diameter catheter shaft <NUM> provides more support for the deflector <NUM> than the smaller diameter articulating distal sheath <NUM>. Once the deflector <NUM> is deployed, tension applied to the catheter shaft <NUM> helps to seat the protection system <NUM> in the aorta <NUM>, covering the ostium of the brachiocephalic trunk <NUM> and the left common carotid artery <NUM>. The deflector <NUM> may be asymmetric with one lobe longer than the other relative with respect to the deflector through-hole. For example, the deflector <NUM> can include a first lobe configured to seal against an ostium of the left common carotid artery <NUM> and a second lobe configured to seal against an ostium of the brachiocephalic artery <NUM>. A length of the first lobe can be measured from the deflector through-hole to an end of the deflector <NUM>, and a length of the second lobe can be measured from the deflector through-hole to an opposite end of the deflector <NUM>. The sealing perimeter of the deflector <NUM> may have a radiopaque feature such as a Platinum- Iridium coil. There may be a frame member embedded in the filter membrane of the deflector <NUM>, or attached to the sealing perimeter of the deflector <NUM> to allow for adjustment to the deflector position in order to ensure a good seal and apposition to the vessel wall. One or more pull wires can be used to deflect the frame member embedded in the filter membrane or attached to the sealing perimeter to properly position the deflector <NUM>.

Following deployment of the deflector element <NUM>, the left subclavian <NUM> can be cannulated and a filter <NUM> can be deployed in the left subclavian artery <NUM> before the branch to the left vertebral artery <NUM> in order to ensure that blood flowing to the left vertebral <NUM> is filtered. The filter <NUM> can be mounted on a filter wire <NUM>. The filter wire <NUM> may have a guide lumen to facilitate delivery over a guidewire. The filter <NUM> can be deployed by advancing the filter wire <NUM> or withdrawing the articulating distal sheath <NUM>. Once deployed, the filter <NUM> is distal to the deflector <NUM>. To remove the protection system <NUM>, the filter <NUM> can be first sheathed, and then the deflector <NUM> can be sheathed.

Alternatively, the filter <NUM> can be first deployed in the left subclavian artery <NUM>, and then the deflector element <NUM> can be deployed in the aortic arch <NUM>. Instead of the right radial or right brachial artery, the protection system <NUM> can also be inserted into the body through the left radial or brachial artery. In this configuration, the deflector <NUM> element covers the left subclavian artery <NUM> and the left common carotid artery <NUM>, and the filter <NUM> can be deployed in the brachiocephalic artery <NUM>.

<FIG> illustrates another example protection <NUM> in which the device can accommodate a single, continuous strand <NUM> that can be fed out of the distal tip of a catheter <NUM>. The fibrous strand <NUM> may have a pre-shaped core <NUM> causing three-dimensional forms <NUM>, <NUM>, <NUM> as the strand <NUM> is deployed. The pre-shaped core <NUM> may be a pre-shaped nitinol wire or other material with sufficient elastic properties to fill the space and block the vessels. External to the core <NUM>, there may be protruding elements <NUM> that intertwine to form a fibrous filter <NUM>, <NUM>, <NUM>. Alternatively, the filter elements <NUM>, <NUM>, <NUM> may be a pre-formed fibrous elements (<FIG>) or twisted weaves (<FIG>). During or prior to retrieval, the retrieval catheter <NUM> or a separate aspiration catheter may be used to aspirate any captured debris. These filters <NUM>, <NUM>, <NUM> formed of a single continuous strand <NUM> may be placed in the order of the left subclavian artery <NUM>, then left common carotid artery <NUM>, and finally the brachiocephalic trunk <NUM>. Alternatively, the order may be reversed. Alternatively, the device may be inserted in the left brachial or radial artery rather than the right.

<FIG> illustrate another filter design that can be used in any of the other embodiments described herein, but for purposes of illustration, are shown in connection with a system similar to protection system <NUM>. Here, the filter elements <NUM>, <NUM>, <NUM> are elongated when collapsed and axially foreshortened when deployed (see partial enlarged view in <FIG>), such that the greatest cross-section area of each filter <NUM>, <NUM>, <NUM> is in the midsection of the respective filter. This configuration may allow for minimizing the profile of each filter, possibly minimizing the number of catheter exchanges during delivery and retrieval. The filter may be formed of wire mesh, like a "Chinese finger puzzle," formed of nitinol wire, laser cut, formed of polymer coated wire, or otherwise. One or more of the filters <NUM>, <NUM>, <NUM> can be foreshortened by using a pre-shaped filter design. Additionally or alternatively, a pull wire can be attached to either end of the filter. Moving one end of the filter relative to the other end of the filter can cause the filter to foreshorten.

As shown in <FIG>, the left subclavian artery <NUM> can be cannulated, and then a distal filter <NUM> can be deployed in the left subclavian artery <NUM>. As shown in the partial enlarged view in <FIG>, the distal <NUM> filter foreshortens upon deployment. Thereafter, the left common carotid artery <NUM> can be cannulated, and a secondary distal filter <NUM> can be deployed in the left common carotid artery <NUM>, as shown in <FIG>. Finally, a proximal filter <NUM> can be deployed in the brachiocephalic artery <NUM>, as shown in <FIG>. The proximal filter <NUM> may have a larger deployed diameter than the distal filter <NUM> and/or the secondary distal filter <NUM>. Each of the filters <NUM>, <NUM>, <NUM> can be connected together by a flexible tether <NUM>, <NUM>. In other configurations, the system <NUM> may be deployed from the left radial or left brachial artery and the filters <NUM>, <NUM>, <NUM> can be deployed in reverse order.

<FIG> illustrate another variation of the design of the filters used in any of the previous embodiments described herein. This filter design creates additional space in the catheter to accommodate controls for the deflector. The filter <NUM> can be foreshortened using any of the techniques described above with respect to <FIG>. The filter <NUM> can include a ring <NUM> that holds the filter <NUM> in a proper position in the vessel wall. As tension is applied to the system or the pull rod <NUM> is pulled back, a proximal side of the filter <NUM> becomes concave while the ring <NUM> maintains the filter <NUM> in the same position.

<FIG> illustrate a method of deploying the filter <NUM>. In the sheathed configuration, the filter <NUM> can be positioned within the sheath <NUM> (see <FIG>). To unsheath the filter <NUM>, the push rod <NUM> can be moved distally while the slotted tube <NUM> is kept stationary. As the push rod <NUM> is moved distally, the sheath <NUM> is moved distally to reveal the filter <NUM> (see <FIG>). The push rod <NUM> can include one or more flanges <NUM> that can push a proximal end of the filter to foreshorten the filter <NUM>. There can be a ring <NUM> welded to secure the push rod <NUM> to the sheath <NUM>. A benefit to this approach is that upon re-sheathing the filter <NUM>, the sheath <NUM> pushes against the filter <NUM> from the distal side, this may collapse the filter <NUM> against the blood flow, ensuring that any particulate is held by the filter and moves inward toward the central lumen.

<FIG> illustrates another example protection system <NUM> in which a guidewires <NUM> can be placed into each respective vessel. The guidewires <NUM> can have a distal feature that allows the filters <NUM>, <NUM>, <NUM> to become permanently affixed once the filters <NUM>, <NUM>, <NUM> and delivery catheter are advanced coaxially in an over-the-wire technique. The guidewires <NUM> may have a pre-shaped element, for example nitinol, to form the span between the vessels. As shown in the figures, this design allows a bare guidewire <NUM> to be placed in each target location with standard guidewire placement techniques either though a guide catheter, through bare wire manipulation, etc. Once the guidewire <NUM> is in place, a filter <NUM>, <NUM>, <NUM> can be introduced over its respective guidewire <NUM>, slid into the target location, and activated to dock the filter <NUM>, <NUM>, <NUM> onto the guidewire <NUM>. This process can be repeated for each filter <NUM>, <NUM>, <NUM>. One of the filters <NUM>, <NUM>, <NUM> or an additional filter could be placed in the same way in the left subclavian artery <NUM>.

<FIG> shows an example of an aortic filter system <NUM>. Rather than locate the protection system at the aortic arch <NUM>, the brain may be protected by filtering in the ascending aorta <NUM>. This approach can protect all three vessels to the brain with one filter <NUM> deployed from a catheter <NUM>. The catheter delivery system for the index procedure can be accommodated by the filter <NUM> so as to retain good wall apposition as the system crosses the filter <NUM>.

To accommodate the procedural catheter <NUM> in this filter design, several design attributes have been identified to enable the filter <NUM> to still seal while having another index procedure catheter <NUM> occupy the same space in the vasculature. The filter <NUM> may not be continuous around the circumference of the filter and may instead be separated into overlapping petals <NUM>, <NUM>, like those of a flower bloom, so that the overall structure and shape of the filter <NUM> is not disturbed by the presence of another catheter <NUM>. <FIG> illustrate certain features of such an aortic filter system <NUM>.

<FIG> illustrates the aortic filter system <NUM> positioned in the ascending aorta <NUM>. <FIG> illustrates the system <NUM> positioned in the ascending aorta with another procedural catheter <NUM> operating in the same space. As shown in <FIG>, this can be accomplished by having two concentric rings of filter petals configured to be deployed from the actuation shaft <NUM> - an inner ring <NUM> and an outer ring <NUM>. The inner ring <NUM> can be located more distal on the shaft <NUM> than the outer ring <NUM> such that a distal end of the outer ring <NUM> extends beyond a distal end of the inner ring <NUM>. Alternatively, the inner and outer rings <NUM>, <NUM> can be attached to the shaft <NUM> at the same axial position, but the outer petals can have a different length than the inner petals.

As shown in <FIG>, the system <NUM> can also include webbing <NUM> that exists between the inner and outer petals in the region of the filter <NUM> where the procedural catheter <NUM> is expected to extend. The webbing <NUM> can be loose, with extra material when the index procedure catheter <NUM> is not present. The webbing <NUM> can have a same material as the inner and/or outer petals. However, when the procedural catheter <NUM> is present, this allows for the inner petal <NUM> to move toward the lumen of the filter <NUM>, while still maintaining a continuous seal with the procedural catheter <NUM>, as shown in FIG. Radiopaque markers <NUM> can be applied to petals help to identify where on the circumference of the filter <NUM> the catheter <NUM> can be accommodated (see <FIG>).

As shown in FIGS. IOC and <NUM>, the system <NUM> can include a waistband <NUM> that is connected to each of the outer petals <NUM> near the base of the petals. This waistband <NUM> serves to draw the outer petals <NUM> together when the procedural catheter <NUM> pushes the waistband <NUM> inward toward the central lumen of the catheter <NUM>. This feature aids in wrapping the outside edge of the procedure catheter <NUM> with the filter <NUM> and tightens the webbing <NUM> discussed earlier against the procedural catheter <NUM>. The waistband <NUM> can be the same or different material as the inner and/or outer petals. For example, the waistband <NUM> can be a wire mesh or polyurethane mesh.

<FIG> illustrate the shape of the inner and outer petals. The outer petals <NUM> (<FIG>) that are designed to rest against the procedural catheter <NUM> are profiled to accommodate the cylindrical shape of the procedural catheter <NUM>, as shown in <FIG>. For example, each outer petal <NUM> can include one or more scalloped or notched features <NUM> on each lateral side of the petal <NUM> to accommodate the procedural catheter <NUM>. Those petals in the inner ring <NUM> (<FIG>) can be of a different shape and much wider in the circumferential direction than the outer petals <NUM> to fill gaps as the outer petals <NUM> shift to accommodate the catheter <NUM>. Therefore, the petals take a shape similar to those drawn in FIGS. IOC and <NUM>.

<FIG> shows an example protection system <NUM> that can be inserted through the right radial or brachial artery. Although, the protection system <NUM> can also be inserted through the left radial or brachial artery.

The protection system <NUM> can include a dual filter assembly <NUM> in which a first filter <NUM> can be deployed in the brachiocephalic trunk <NUM> and a second filter <NUM> can be placed in the left common carotid artery <NUM>. The dual filter assembly <NUM> can be arranged as disclosed in <CIT>. The left subclavian artery <NUM> can be provided with a distal accessory filter <NUM>.

As shown in <FIG>, a cross-section through line 11B-11B shows a proximal terminating tube <NUM> of proximal filter <NUM> positioned radially inward of the outer sheath <NUM>, a shaft <NUM> of the articulating distal sheath <NUM> positioned radially inward of the proximal terminating wire or tube <NUM>, and the distal filter shaft <NUM> positioned radially inward of the shaft <NUM> of the articulating distal sheath <NUM>. The distal filter shaft <NUM> carries the secondary distal filter <NUM>. A pull wire <NUM> extends in a space between the distal filter shaft <NUM> and the shaft <NUM> of the articulating distal sheath <NUM> or through a wall of the shaft <NUM> of the articulating distal sheath <NUM>. As shown in <FIG>, a cross-section taken through line 11C-11C shows the articulating sheath <NUM> with the pull wire <NUM> extending through the wall of the articulating distal sheath <NUM> and the distal filter shaft <NUM> positioned radially inward of the articulating distal sheath <NUM>. The distal accessory filter <NUM> is mounted on a filter wire <NUM> that extends through the space <NUM> between the articulating distal sheath <NUM> and the distal filter shaft <NUM>.

<FIG> shows a component of a distal filter accessory assembly <NUM>. The distal filter accessory assembly <NUM> can include a distal filter <NUM> mounted on a filter wire <NUM>. The filter wire <NUM> can have a guide lumen for delivery over a guidewire <NUM>. The filter wire <NUM> can be independently steerable. Additionally or alternatively, the distal filter <NUM> can be delivered through a filter sheath <NUM>. The filter sheath <NUM> may have a pre-set curve shape or be deflectable using any features of the above-described articulating distal sheaths.

As shown in FIG. HE, when fully deployed, the filter wire <NUM> can extend through a port <NUM> in the articulating distal sheath <NUM>. <FIG> shows the distal filter <NUM> and the proximal filter <NUM> being deployed before the articulating distal sheath <NUM> cannulates the left common carotid artery <NUM>, but in other configurations, the secondary distal filter <NUM> may be deployed before the proximal filter <NUM> and/or the distal filter <NUM>.

As shown, in <FIG>, in this example, the distal accessory filter <NUM> can be delivered into the left subclavian artery <NUM>. The articulating sheath <NUM> can be delivered over the distal filter accessory assembly <NUM> with the distal filter accessory assembly <NUM> extending out of a port <NUM> in the articulating distal sheath <NUM>. The filter sheath <NUM> can be delivered through a guide catheter <NUM> or include articulating features for steering, such as those described with respect to the above-described articulating distal sheaths. Alternatively, the filter sheath <NUM> may have a pre-set curve shape or be deflectable.

<FIG> schematically illustrate the delivery sequence for the protection system <NUM>. In <FIG>, the filter wire <NUM> is loaded into the filter sheath <NUM> and into the configuration shown in <FIG>. The first filter assembly <NUM> is shown in its deployed configuration in FIG. HI and its collapsed configuration in <FIG>. A guidewire <NUM> can be loaded into the first filter assembly <NUM>. <FIG> illustrates the right radial access point <NUM> and the target location <NUM>.

<FIG> illustrates a method of deploying the protection system <NUM>. The left subclavian artery <NUM> can be first accessed with an access catheter <NUM> over a guidewire <NUM> (<FIG>). The guidewire <NUM> can be removed (<FIG>) and the accessory filter assembly <NUM> can be inserted through the access catheter <NUM>. Alternatively, the accessory filter assembly <NUM> can be inserted without the filter sheath <NUM>. The accessory filter sheath <NUM> can be retracted to deploy the filter <NUM> (FIG. UN) or the distal filter <NUM> can be advanced distally of the filter sheath <NUM>. The guide catheter <NUM> and the accessory filter sheath <NUM> can then be removed, leaving the accessory filter assembly <NUM> in place. The accessory filter assembly <NUM> can then be loaded into the dual filter assembly <NUM> as shown in <FIG> with the filter wire <NUM> entering a guidewire entry port <NUM>. The dual filter assembly <NUM> can be loaded over an independent guidewire <NUM>. The dual filter assembly <NUM> can be advanced over the independent guidewire <NUM>. A proximal filter <NUM> can be deployed in the brachiocephalic trunk <NUM> (FIG. After the proximal filter <NUM> has been deployed, the independent guidewire <NUM> can be retracted, the articulating sheath <NUM> can be deflected, and the left common carotid artery <NUM> can be cannulated with the guidewire <NUM>. The dual filter assembly <NUM> can be pulled back so articulating distal sheath <NUM> rests against the vessel carina (<FIG>). A secondary distal filter <NUM> can be placed in the left common carotid artery <NUM>, as shown in <FIG>.

Although certain filter assemblies have been described or illustrated herein as including a filter, the filters described herein can also be a self-expanding stent, a balloon, a deflector, or other occluding device.

Although certain filter assemblies have been described or illustrated herein as being introduced through a right radial or right brachial artery, the filter assemblies may alternatively be introduced through a left radial or left brachial artery. Similarly, although certain filter assemblies have been described or illustrated herein as being introduced through a left radial or left brachial artery, the filter assemblies may alternatively be introduced through a right radial or right brachial artery.

As used herein, the relative terms "proximal" and "distal" shall be defined from the perspective of the protection system. Thus, proximal refers to the direction of the handle portion of the delivery system and distal refers to the direction of the distal tip.

Conditional language used herein, such as, among others, "can," "might," "may," "e.g.," and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that some embodiments include, while other embodiments do not include, certain features, elements, and/or states. Thus, such conditional language is not generally intended to imply that features, elements, blocks, and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular embodiment.

The terms "approximately," "about," and "substantially" as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms "approximately", "about", and "substantially" may refer to an amount that is within less than <NUM>% of, within less than <NUM>% of, within less than <NUM>% of, within less than <NUM>% of, or within less than <NUM> % of the stated amount.

It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art may recognize that the disclosure may be embodied or carried out in a manner that achieves one advantage or a group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.

The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. Further, the actions of the disclosed processes and methods may be modified in any manner, including by reordering actions and/or inserting additional actions and/or deleting actions.

Claim 1:
A protection system (<NUM>) for preventing embolic material from entering the cerebral vasculature, the protection system (<NUM>) comprising:
an articulating distal sheath;
a first filter (<NUM>);
a second filter (<NUM>) connected to the first filter (<NUM>) by a first tethering portion (<NUM>); and
a third filter (<NUM>) connected to the second filter (<NUM>) by a second tethering portion (<NUM>);
wherein each of the first filter (<NUM>), the second filter (<NUM>), and the third filter (<NUM>) is configured to be deployed from the articulating distal sheath,
characterized in that, when collapsed in the articulating distal sheath, an apex of each of the first filter (<NUM>), the second filter (<NUM>), and the third filter (<NUM>), is oriented distally of an open end of the respective filter.