Patent Description:
Cerebral embolism is a known complication of cardiac surgery, cardiopulmonary bypass, and catheter-based interventional cardiology and electrophysiology procedures. Embolic particles, including thrombus, atheroma, and lipids, may become dislodged by surgical or catheter manipulations, enter the bloodstream, and "embolize" to the brain or other vital organs downstream. Cerebral embolism can lead to neuropsychological deficits, stroke, and even death. Other organs downstream of an embolic release can also be damaged, resulting in diminished function or organ failure.

Of particular interest to the present invention, a number of procedures are performed on aortic valves using catheters advanced over the patient's aortic arch. Valvuloplasty procedures have been performed for many years and use high pressure balloons advanced over the aortic arch to disrupt calcifications on the aortic valve. Such procedures present a significant risk of emboli release to the cerebral arteries. More recently, percutaneous aortic valve replacement (PAVR) procedures, also known as transcatheter aortic valve implantation (TAVI) procedures or transcatheter aortic valve replacement (TAVR) procedures, have been approved, and their use has become widespread. While offering many patient benefits, they also present a significant risk of emboli release, particularly when performed transvascularly with catheters introduced over the aortic arch.

The prevention of embolism in these and other procedures would benefit patients and improve the outcome of many surgical procedures. Given that potential emboli are often dislodged during catheter-based procedures that involve more than one access site and more than one procedural device, it would be advantageous to deploy an embolic protection system that provides multiple access paths through or beyond the protection device to perform diagnostic and interventional procedures with multiple catheters. It would be further advantageous to integrate the embolic protection system on a sheath that is being used to perform the procedure, such as is used with an angiographic diagnostic catheter, a transcatheter valve delivery system, and an electrophysiology catheter.

<CIT>, commonly assigned herewith, describes an introducer sheath, intended specifically for use in valvuloplasty and TAVR procedure, which addresses some of the shortcomings of prior embolic protection sheath access devices. The '<NUM> sheath includes embolic protection elements and is suitable for advancing a contrast or other small catheter through the sheath and a second catheter through port formed in a filter. While a significant improvement over previous embolic protection access sheathes having features, particular designs of the '<NUM> access can be challenging to deploy and retrieve, can lose small amounts of emboli, and can have a relatively large profile during deployment.

Therefore, it would be desirable to provide improved devices, systems, and methods for preventing embolism during cardiac and other procedures performed over the aortic arch. Such devices, systems, and methods should offer less complicated deployment protocols, should have a relatively low profile when being deployed, and should afford reliable and efficient emboli containment at all times during a procedure. At least some of these objectives will be met by the inventions described herein.

Description of the Background Art. <CIT>has been described above. Other filters and devices for preventing cerebral embolism are described in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>; <CIT>; and <CIT>; <CIT>;<CIT>;<CIT>; <CIT>; <CIT>; <CIT>; <CIT>;<CIT>; <CIT>; <CIT>; and <CIT>.

<CIT> describes intravascular embolic protection apparatus including a blood filter element having an accommodating passageway adapted to permit passage of a procedure device therethrough and to substantially seal against passage of particles between the embolic protection apparatus and the procedure device by accommodating to a size and shape of the procedure device. A method is described of performing an endovascular procedure on a patient including the steps of delivering an embolic protection apparatus to a location within a vascular lumen of the patient; passing a procedure device through an accommodating passageway of the apparatus, the accommodating passageway accommodating to a size and shape of the procedure device; performing the endovascular procedure; and removing the procedure device from the patient. <CIT> discloses a luminal emboli capture device to be inserted in the patient's aortic arch vessels during cardiac surgery.

The present disclosure provides methods, systems, and devices for collecting emboli and in particular for preventing the release of emboli into the cerebral vasculature during the performance of interventional procedures in a patient's aorta, including aortic valve replacement, aortic valve valvuloplasty, and the like, where there is a risk of emboli being released into the aortic side vessels, including the brachiocephalic artery, the left carotid artery, and the left subclavian artery. The present disclosure provides embolic protection devices, tubular filter bodies, and systems and methods for placement of the devices and filters through the descending aorta and over the aortic arch to inhibit emboli release into the aortic side branch vessels while allowing simultaneous access to the aortic valve by one, two, three or more interventional and/or diagnostic catheters being introduced from the descending aorta, typically by conventional unilateral or bilateral femoral artery access.

The embolic protection devices include a filter body and a deployment catheter body connected to the filter body. The filter body typically comprises a tubular porous mesh material and has an open upstream end to allow the entry of blood flow and emboli and an open downstream end to allow entry of at least one working catheter and usually two or more working catheters simultaneously. The deployment catheter body is directly or indirectly coupled to the open downstream end of the filter body, where upstream and downstream refer to the direction of blood flow, e.g. downstream is toward the descending aorta and away from the heart and aortic arch. At least one self-sealing port or passage is provided in an interior of the filter body, and the deployment catheter body typically has at least one lumen to provide at least one access route to an interior of the tubular filter body for introducing a diagnostic, interventional or other working catheter through the self-sealing port. Preferably, one or more additional working catheters may be introduced through the same self-sealing passage simultaneously or sequentially with a first catheter introduced through the sheath. Additional self-sealing or other catheter-access ports could be included to provide other, parallel access routes through the filter body but are not usually necessary as the self-sealing passage will typically have a diameter which is sufficiently expandable to allow the simultaneous passage of two or more catheters while being able to close to block emboli release when no catheter is present. Other axially aligned self-sealing catheter-access ports could also be included to provide additional emboli capture chambers within the filter body.

Where in the description the unit "inch" is employed the following conversion applies: <NUM> inch = <NUM>.

In a first specific aspect of the present disclosure, an embolic protection device comprises a filter body formed from a tubular porous mesh material and having an open upstream end and an open downstream end. A self-sealing port is spaced inwardly from each of the ends, and the self-sealing port includes an expandable opening configured to conform to at least one working catheter passing therethrough. A radially collapsible support is coupled to a periphery of the downstream end of the filter body, and a catheter body having a distal end is coupled to the radially collapsible support, where distal refers to a direction on the device away from the operator, i.e., further away from the portion of the device that is outside the body. Similarly, the term proximal refers to a direction of the device closer to the operator, i.e., nearer to the portion of the device that is outside the body. A delivery sheath has a lumen configured to receive and radially constrain the filter body such that the catheter body may be distally advanced relative to the delivery sheath to release the filter body from constraint and to allow the filter body to radially expand with the support circumscribing the downstream end of the filter body. In this way, the catheter body may be distally advanced and proximally retracted relative to the delivery sheath to move the assembly of the support and filter body out of and into the lumen of the delivery sheath. In particular, when advanced out of the delivery sheath, the support will open to assist in deployment of the downstream end of the filter body and, when retracted back into the delivery sheath, the support will close to collapse the downstream end of the filter body prior to the filter body being drawn into the lumen.

In particular embodiments, the filter body has an open cylindrical chamber disposed between a downstream end of the port and the downstream end of the filter body. The port may comprise a wall portion up the tubular porous mesh material, where the wall portion folds, inverts, or otherwise deflects radially inwardly as other wall portions expand when released from radial constraint from the delivery sheath. In still other particular embodiments, the wall portion inverts to form a port having a conical opening or base on a downstream side. For example, the inverted wall portion of the tubular porous mesh material may have a resiliently closed sleeve portion extending in an upstream direction from an apex of the conical opening or base which defines the expandable opening of the port.

In still further particular embodiments, the radially collapsible support may comprise a loop secured around the periphery of the downstream end of the filter body. The loop may be connected to a tether which passes through a deployment lumen in the catheter body. The loop may be configured as a lasso to allow the tether to draw the open end of the filter body closed prior to drawing the filter body into the lumen of the delivery sheath. Alternatively, the radially collapsible support may comprise a scaffold having an open end coupled to the periphery of the downstream end of the filter body and a constricted end coupled to the distal end of the catheter body.

In still other particular embodiments of the present disclosure, the catheter body will include a lumen for receiving at least one working catheter so that the working catheter may be advanced through the lumen and into the open downstream end of the filter body and then through the port. The catheter body may further include at least one additional lumen for receiving a tether attached to the radially collapsible support. Additional lumens may also be provided for other purposes.

In a second specific aspect of the present disclosure, a luminal emboli capture device comprises a filter body formed from a tubular porous mesh material and having an open upstream end, an open downstream end, and at least a first port spaced inwardly from each of the ends. The port comprises an expandable opening configured to conform to at least one working catheter passing therethrough, and the filter body will have at least an open cylindrical chamber at its downstream end and an open cylindrical chamber at its upstream end, where the port is disposed therebetween. The emboli capture device may further comprise a catheter body having a distal end coupled to the downstream end of the filter body.

In specific embodiments, the porous mesh material comprises a fabric of knitted, braided, woven, or nonwoven fibers, filaments, or wires having a pore size chosen to prevent emboli over a predetermined size from passing therethrough. In many embodiments, the fabric will be double-walled over at least a portion of the tubular mesh, and the porous mesh material may be made of a resilient metal, a polymer material, a malleable material, a plastically deformable material, a shape-memory material, or combinations thereof. In further specific cases, the porous mesh material may have an anti-thrombogenic coating on its surface, and the pore size will typically be in the range from about <NUM> to about <NUM>. An exemplary porous mesh material comprises a double layer braid formed from <NUM> individual wires, including a combination of <NUM> Nitinol® (nickel-titanium alloy) wires and <NUM> tantalum wires, each wire being <NUM> inch in diameter, formed to a final double-layer mesh diameter of between <NUM> and <NUM>.

In further particular embodiments, the at least first port is formed from or comprises a wall portion of the tubular porous mesh material. The wall portion is formed or shaped, e.g. being thermally shaped and set, so that the port folds or closes radially inwardly as other wall portions expand when released from constraint. The wall portion will typically be pre-shaped to invert to form a port with a conical opening on a downstream side, and, typically, a closed sleeve portion extending in an upstream direction from an apex of the conical opening which defines the expandable opening of the port. In alternative embodiments, the port may be defined by a wall portion of the tubular porous mesh which is constricted, pinched, or otherwise closed radially inwardly but will open in response to the passage of the working catheter(s) therethrough. In a particular embodiment, in additional to the upstream and downstream chambers, the filter body may have one or more open "central" cylindrical chambers between a downstream end of the first or other port and an upstream end of the second or other port.

In a third specific aspect of the present disclosure, a clot retrieval system comprises an embolic protection device as just described in combination with a clot retrieval working catheter having a clot capture distal end, where the clot retrieval working catheter is configured to draw retrieved clot in a downstream direction through an open upstream end on the filter body into a central chamber.

In a fourth specific aspect, the present disclosure provides a method for advancing a working catheter into and/or over a patient's aortic arch. A cylindrical filter body formed at least partly from a porous mesh is provided. The cylindrical filter body defines a collection chamber for emboli and has an open upstream end, an open downstream end, a self-sealing port spaced inwardly from each of the ends, and a radially collapsible support coupled to a periphery of the downstream end of the filter body. A deployment catheter which carries and constrains the cylindrical filter body is advanced to a downstream side of the aortic arch while the filter body remains in its radially constrained configuration, typically with a previously placed delivery sheath. The cylindrical filter body is radially expanded so that a wall of the porous mesh covers the patient's aortic side or branch vessels and the open upstream end of the filter body faces the patient's heart. Blood flows into an interior of the filter body through the open upstream end, and emboli collect in the collection chamber. As the filter body is deployed, the support radially expands to hold the downstream end of the filter body open, and blood flowing through the porous mesh of the filter body and into the aortic side vessels is substantially emboli free. After the filter body is deployed, a first working catheter can be advanced through the open downstream end of the filter body and through the self-sealing port and toward the heart. Optionally, a second working catheter may be advanced through the open downstream end of the filter body and through the self-sealing port toward the heart, either simultaneously or sequentially with placement of the first working catheter.

In particular embodiments, a first diagnostic or interventional procedure may be performed with the first working catheter and a second diagnostic or interventional procedure may be performed with the second catheter. It will be appreciated that third, fourth, and additional working catheters may also be introduced and advanced either simultaneously or sequentially with other working catheters.

The first working catheter is typically introduced through a lumen in the deployment catheter, and the second working catheter may be introduced in parallel to the deployment catheter. In this way, the delivery profile of the deployment catheter can be minimized. In one example, a first working catheter will be used to introduce contrast media to an interventional site while a second working catheter will perform an interventional procedure at that site. More specifically, the interventional procedure may comprise delivery of a prosthetic aortic valve, performance of valvuloplasty, or the like.

In still further particular embodiments, the deployment catheter is advanced while present in a delivery sheath which radially constrains the cylindrical filter body. Radially expanding the cylindrical filter body may comprise proximally retracting the delivery sheath relative to the deployment catheter. Typically, the radially expanded filter body is retrieved by retracting the deployment catheter to collapse the radially collapsible support to close the open downstream end of the filter and draw the closed downstream end of the filter body into the delivery sheath. More specifically, retracting the deployment catheter to collapse the radially collapsible support may comprise retracting a tether present in the lumen of the deployment catheter to first collapse the radially collapsible support to close the downstream end of the filter body and then to retract the deployment catheter to draw the closed downstream end of the filter body into the delivery sheath.

In still further embodiments, the filter may contain one or more support structures or wires that provide longitudinal stiffness to the device to prevent compression or movement of the filter during the procedure. Such wires or structures may extend the full length of the device or only for a portion of its length and such wires or structures shall be either fixedly or slidably attached to the access sheath.

As shown in <FIG>, an embolic protection device <NUM> comprises a filter body <NUM> having an open upstream end <NUM> and an open downstream end <NUM>. The filter body <NUM> is typically formed from a porous mesh material, more typically a tubular porous mesh material which is preformed to have a self-sealing port <NUM> with an expandable opening <NUM> located between the open upstream end <NUM> and the open downstream end <NUM>, typically closer to the open downstream end as illustrated. Specific folding patterns for the filter body <NUM> are described below with reference to <FIG>, and several exemplary alternative folding patterns are described below in connection with <FIG>.

A radially expandable/collapsible support <NUM> is secured at the open downstream end <NUM> of the filter body <NUM>, as best seen in <FIG>. The radially collapsible support <NUM> may comprise a tube <NUM> (<FIG>) having a pull wire <NUM> with a loop <NUM> formed at its distal end. The loop <NUM> is secured about the periphery of the open downstream end <NUM> of the filter body <NUM> so that it may act as a "lasso" or a "purse-string" component for opening and closing the open downstream end <NUM>. In particular, by proximally retracting the pull wire <NUM> within the tube <NUM> (to the right in <FIG>), the loop <NUM> may be closed. Conversely, by distally advancing the pull wire <NUM> relative to the tube <NUM>, the loop <NUM> may be open. As described in more detail below, by axially advancing and retracting the tether structure <NUM>, the filter body <NUM> may be positioned relative to a deployment catheter body <NUM>.

The self-sealing port <NUM> of the filter body <NUM> divides the filter body into an upstream cylindrical chamber 26A and a downstream cylindrical chamber 26B. Each of the chambers 26A and 26B will be generally free from internal structure, and the self-sealing port <NUM> will act to divide the two chambers and, in particular, to prevent passage of emboli which may enter the upstream chamber 26A into or beyond the downstream chamber 26B. The downstream cylindrical chamber 26B acts to receive and facilitate introduction of working catheters into and through the self-sealing port <NUM> in order to perform interventional procedures upstream of the filter body <NUM> when the filter body is deployed in the aorta or other blood vessels.

The deployment catheter body <NUM> has a distal end <NUM> and at least a first lumen <NUM> for carrying the tether structure <NUM> and a second lumen <NUM> which serves as a working lumen for introducing interventional or working catheters therethrough, such as TAVR catheters for deploying prosthetic aortic valves as will be described in detail below.

A proximal or control hub <NUM> is coupled to a proximal end <NUM> of the deployment catheter body <NUM>. A proximal end <NUM> of the tether structure <NUM> extends from the control hub <NUM> and allows a user to manipulate the tether structure, and including both axial retraction and advancement of the tether structure as well as opening and closing of the loop <NUM>. The control hub <NUM> also has a port <NUM> which opens to the second lumen <NUM> in the catheter body <NUM> for allowing passage of guide wires, working catheters, and the like.

The filter body <NUM> will typically be self-expanding. By "self-expanding," it is meant that the filter body will be resilient and have a normally open or expanded configuration when free from radial and/or axial constraint. By either radially contracting or axially extending the filter body, the diameter or profile of the filter body will be reduced so that it can be intravascularly introduced to a working site in the patient's vasculature, typically over the aortic arch but optionally in other locations as well. Additionally, by radially collapsing and/or axially extending the filter body, the self-sealing port within the filter body will be unfolded and axially extended.

The self-sealing port <NUM> will be self-forming, typically having a conical base <NUM> and an extending sleeve <NUM>, as shown in <FIG>. The self-sealing port <NUM> will have at structure which is formed by folding and inverting the generally tubular structure of the filter body as the radius of the filter body increases and the length of the filter body axially shortens. The necessary fold lines will be pre-formed into the filter body, typically by heat treatment. In exemplary embodiments, the filter body will be formed as a Nitinol® (nickel-titanium alloy) thin wire mesh which will be formed to have the fold lines described in more detail with reference to <FIG> below. These pre-formed fold lines will allow the filter body to be axially elongated and radially collapsed to have a low profile during delivery, typically having a delivery diameter below <NUM> Fr (French), often below <NUM> Fr. Conversely, the filter body will typically open to an unconstrained width or diameter above <NUM>, often above <NUM> more often above <NUM>, and typically in the range from <NUM> to <NUM>. As will be described in more detail below, the filter body <NUM> will be introduced in its low profile configuration through a delivery sheath <NUM> which has been pre-placed in the patient's artery, typically through the femoral artery over the aortic arch. In order to advance the filter body into the delivery sheath <NUM>, however, it is necessary to temporarily constrain the self-expanding filter body <NUM>. This may be achieved using a peel-away sheath <NUM>, as shown in <FIG>. The filter body <NUM> is axially elongated and radially collapsed and drawn into the lumen of the peel-away sheath <NUM>, as shown in <FIG>. The peel-away sheath covers the filter body <NUM> with the catheter body <NUM> extending from a proximal end of the peel-away sheath <NUM>. The temporary assembly of the peel-away sheath and the catheter body <NUM> can be introduced over a guidewire structure <NUM> which has been pre-placed through a distal port <NUM> of the delivery sheath <NUM>, as shown in <FIG>, with the sheath then being advanced through the distal port <NUM>, as shown in <FIG>. Once the distal end of the filter body <NUM> has been introduced through the port <NUM> into the proximal end of the delivery sheath <NUM>, the peel-away sheath may be removed as the filter body continues to be introduced into the delivery sheath <NUM>. To facilitate delivery, each of the delivery sheath <NUM> and the peel-away sheath <NUM> may have ports to allow the introduction of fluids into their lumens.

As shown in <FIG>, the delivery sheath <NUM> will be introduced through the patient's groin into a femoral artery and up and over the aortic arch in a conventional manner. A second sheath <NUM>, typically for introducing a TAVR or other interventional or working catheter, will be positioned in the contralateral femoral artery for introducing the working catheter up the aorta and over the aortic arch AA in parallel to the delivery sheath <NUM>. Such positioning will be intended for prosthetic valve placement or other interventional procedures on the patient's P heart H.

Referring now to <FIG>, a particular protocol for introducing a prosthetic valve PV into the patient's native aortic valve AV will be described. As shown in <FIG>, the delivery sheath <NUM> is initially placed over the guidewire structure <NUM> as just described with reference to <FIG>. The catheter body <NUM> is then advanced through the inner lumen of the delivery sheath <NUM> such that the radially constrained filter body <NUM> approaches the open distal end <NUM> of the delivery sheath.

By then holding the catheter body <NUM> relatively still or stationary and retracting the delivery sheath <NUM> in a proximal direction, i.e., away from the patient's aortic valve AV, the distal end of the filter body <NUM> will be released from constraint so that the tubular porous mesh <NUM> will begin to radially expand, as shown in <FIG>. The delivery sheath <NUM> continues to be proximally retracted, as shown <FIG>, so that the tubular porous mesh <NUM> expands and engages the inner wall of the ascending aorta immediately above the aortic valve AV. As shown in <FIG>, the delivery sheath <NUM> continues to be proximally withdrawn, allowing the tubular porous mesh <NUM> to continue to expand and to begin covering the branch vessels BV, with relative full deployment of the upstream cylindrical chamber 26A of the filter body <NUM> shown in <FIG>. As also shown in <FIG>, the self-sealing port structure <NUM> is at its very initial stages of being formed, with further formation being shown in <FIG>.

As shown in <FIG>, the conical base <NUM> of what will become the self-sealing port <NUM> is largely formed, and the downstream cylindrical chamber 26B begins to form as shown in <FIG>. The downstream cylindrical chamber 26B is largely formed as shown in <FIG> while the self-sealing port <NUM> is just beginning to form. By then advancing the catheter body <NUM> in the direction toward the aortic valve AV, as shown in <FIG>, a narrowed segment of the tubular porous mesh <NUM> will begin to invert to form the sleeve structure <NUM> of the port <NUM>. As also apparent in <FIG>, the radially collapsible support <NUM>, in the form of the loop <NUM>, opens to open and support the open distal end of the downstream cylindrical chamber <NUM>. It is this support structure <NUM> which allows the catheter body <NUM> to manipulate the downstream portion of the filter body <NUM> so that the downstream cylindrical chamber 26B can be advanced distally or toward the aortic valve AV relative to the upstream cylindrical chamber 26A. The radially expandable/collapsible support 24A will also be useful when retracting the filter body <NUM> at the end of the procedure, as will be described in more detail below.

The fully deployed self-sealing port <NUM> is shown in <FIG> with the sleeve <NUM> defining the expandable opening <NUM> and the conical base <NUM> facilitating introduction of catheters from the downstream end, as shown in more detail below.

In specific examples, the guidewire structure <NUM> may include an external support tube which may be retracted and withdrawn to leave the guidewire in place, as shown in <FIG>. A diagnostic catheter <NUM> may then be advanced over the guidewire <NUM>, as shown in <FIG> typically being used for angiography. This port <NUM> will expand to accommodate the diameter of the diagnostic catheter <NUM> while sealing around the catheter to prevent any emboli from passing through the port.

After withdrawing the diagnostic catheter <NUM>, another guidewire <NUM> may be introduced for advancing a TAVR delivery catheter <NUM>, as shown in <FIG>. The first catheter structure <NUM> will typically be left in place although it is not visible in <FIG>. The TAVR delivery catheter <NUM> is then advanced over the patient's aortic arch AA, as shown in <FIG>, until it passes through the native aortic valve AV, as shown in <FIG>. A prosthetic valve PV will then be released from the TAVR catheter <NUM>, as shown in <FIG>. It should be appreciated that during the advancement of the TAVR catheter <NUM> over the aortic arch AA, and in particular during release of the prosthetic valve PV, there is a substantial risk of emboli being released as the aortic arch and the aortic valve AV may be heavily calcified. If such emboli are present, they will be carried over the aortic arch and through open upstream end <NUM> of the filter body <NUM> so that they enter and are contained within the upper cylindrical chamber 26A. In particular, the tubular porous mesh <NUM> will prevent emboli of any significant size from entering any of the branch vessels BV while allowing blood flow into these vessels. The sleeve <NUM> of the self-sealing port <NUM> will conform to and seal around the exterior of the TAVR delivery catheter <NUM>, thus inhibiting or preventing accidental passage of emboli through the port while it is expanded to permit catheter passage.

After the prosthetic valve PV has been released, as shown in <FIG>, the TAVR delivery catheter <NUM> will be proximally retracted over the guidewire <NUM>, as shown in <FIG>. The first guidewire <NUM> is also shown in <FIG>. The TAVR delivery catheter <NUM> continues to be withdrawn and exits through the self-sealing port <NUM> which then closes over the guidewire <NUM>, as shown in <FIG>. The TAVR guidewire <NUM> is then pulled back through the aorta, as shown in <FIG>.

After the TAVR catheter <NUM> and guidewire <NUM> have been withdrawn, the prosthetic valve PV is in place and it is necessary to withdraw the filter body <NUM> from the aortic arch AA. As shown in <FIG>, the tether structure <NUM> is manipulated to close the loop <NUM> of the radially collapsible support <NUM>. In addition to closing the loop <NUM>, the proximal end of the filter structure <NUM> is drawn to the distal end of the catheter body <NUM>, and the catheter body <NUM> retracted to draw the filter body into the delivery sheath <NUM>, as shown in <FIG>.

The catheter body <NUM> continues to be proximally withdrawn so that it pulls the downstream cylindrical chamber <NUM> into the delivery sheath <NUM>, as shown in <FIG>, and continues to be proximally withdrawn until the entire filter body <NUM> is drawn into the delivery sheath <NUM>, as shown in <FIG>. The filter body and all emboli contained therein are then safely captured within the delivery sheath <NUM>, and the delivery sheath <NUM> may be withdrawn from the patient and the procedure may be completed in a conventional manner.

The porous filter mesh material may comprise a variety of knitted, woven or nonwoven fibers, filaments or wires, and will have a pore size chosen to allow blood to pass through but prevent emboli above a certain size from passing through. Suitable materials include resilient metals, such as shape and heat memory alloys, polymers, and combinations thereof, and the materials may optionally have an anti-thrombogenic coating (such as heparin) on their surfaces. The filter meshes may further incorporate materials and structures to enhance the radiopacity of the filter body. Exemplary materials include gold, platinum, palladium, or tantalum, and other metals having a greater radiopacity than the resilient metals, as well as radiopaque coatings or fillings. In other cases, the resilient metal filaments or wires may be served with thinner, more radiopaque wires or filaments.

The filter body maybe constructed in discrete sections that are attached together, but will more typically be formed from a continuous cylindrical mesh structure that is narrowed or folded in sections to form the specific design features, typically consisting of a single such folded tubular mesh structure. Forming the device from one continuous cylindrical mesh allows the filter body to be axially stretched for deployment and/or retrieval, thereby reducing the profile of the filter. Another advantage of a filter formed from a single, continuous tabulate mesh material is that it will contain only smooth, rounded edges. Such edges minimize friction and snagging with catheters and the procedural tools being introduced through the filters.

The self-sealing port may be configured as a conical structure with the access port at its narrow end, typically formed by a sleeve as described previously. In other embodiments, as illustrated below, the self-sealing port may be a simple narrowing of the cylindrical structure, e.g. a self-closing neck region which seal around catheters and other tools introduced therethrough. Whatever the particular geometry, the self-sealing port can be formed by shape-setting a larger, tubular or cylindrical mesh in a reduced diameter via heat treatment or cold forming. In addition, other embodiments of the self-sealing port can be straight, contain a twist, be corrugated, have a flattened section, or possess other features that assist in its ability to close around procedural devices sufficiently to inhibit or prevent emboli from passing through when a catherter is in place. In still other embodiments, the filter body may contain two or more such self-expanding port structures. The port <NUM> may accommodate a single device (such as a guidewire, catheter, valve delivery system, pacing lead, etc.), two devices or more than two devices simultaneously and can expand and contract to maintain a sufficient seal around multiple devices as needed. Further, such devices can be introduced through the downstream cylindrical chamber 26B and into the port <NUM> by way of the working lumen <NUM> of the catheter body <NUM> or directly by way of a second sheath <NUM> in an alternative access site, or in some combination thereof.

Referring now to <FIG>, a number of different patterns for forming the tubular porous mesh material <NUM> into a filter body <NUM> having the self-sealing port <NUM> between the upstream cylindrical chamber 26A and the downstream cylindrical chamber 26B are illustrated. It will be appreciated that each of the structures in <FIG> begins with a single layer tube of a mesh material as just described. In the configuration of <FIG>, the tubular structure is first folded into a bi-layer structure having a fold 14A in its middle. The bi-layer structure is then folded back upon itself and inverted in order to form the illustrated filter body 12a having a structure which is then heat set in the fully radially expanded configuration.

The filter body 12b of <FIG> similarly begins as a bi-layer tubular mesh with a single fold 14B at one end. The bi-layer structure is then folded similarly to the pattern of <FIG>, except that the open end of cylindrical chamber 26A is folded in an inwardly inverted pattern rather than in a simple fold-back pattern as shown in <FIG>.

The filter body 12c illustrated in <FIG> is again similar in most respects to the fold pattern of filter 12a of <FIG>, except that the open end of the upstream cylindrical chamber 26A has an inner layer folded over an outer layer to form a distal cuff, where the inner layer terminates within the folded-back outer layer.

The filter body 12d illustrated in <FIG> is in many ways the inverse of that filter body 12a of <FIG>. A single fold 14D in the original single-layer tubular cylinder is located at the open end of the upstream cylindrical chamber 26A. The open downstream end of downstream chamber 26B is folded back on itself to form a cuff structure.

Filter body 12e as illustrated in <FIG> is the simplest structure of all where folding of the downstream cylindrical chamber 26B is similar to that in <FIG>, but the open end of the upstream cylindrical chamber 26A terminates with the inner and outer layers open and not folded back at all.

<FIG> illustrates a first alternative embodiment of an embolic protection device <NUM>. A filter body <NUM> has an open upstream end <NUM> and a closed downstream end <NUM>. A self-sealing port <NUM> is formed in the closed downstream end <NUM>, and a support structure <NUM> is attached at a downstream end of the filter body. The support structure <NUM> comprises a pair of struts and can be made of a material (such as a shape memory alloy) that can be compressed for delivery and expanded in situ by the release of a constraining sheath <NUM>. The support is fixedly or movably attached to a deployment catheter body <NUM> via a collar <NUM>. A distal or upstream end of the catheter body <NUM> passes through the closed end <NUM> of the filter body <NUM> adjacent to the self-sealing port <NUM>.

<FIG> illustrates a second alternative embodiment of an embolic protection device <NUM>. A filter body <NUM> with a closed downstream end <NUM> is attached to a deployment catheter body by fully circumferential support structure <NUM>. The support structure <NUM> comprises "stent-like" diamond elements over the region where the support structured overlaps and is attached to the mesh material of the filter <NUM>. The support structure <NUM> is fixedly or movably attached to a deployment catheter body <NUM> via a collar <NUM> and a plurality of struts <NUM>. A distal or upstream end of the catheter body <NUM> passes through the closed end <NUM> of the filter body <NUM> adjacent to a self-sealing port <NUM>.

<FIG> illustrate a third alternate embodiment of an embolic protection device <NUM> having a conical mesh self-sealing port <NUM> in a closed end <NUM> of a filter body <NUM>. A deployment catheter body <NUM> is attached by a collar <NUM>. A delivery sheath <NUM> is provided for delivery and traction of the filter body <NUM>. In <FIG>, a distal or upstream end of the catheter body <NUM> is disposed through the self-sealing port <NUM> and provides an introductory lumen or other path through the port adjacent to the self-sealing port <NUM>. In <FIG>, a TAVR delivery or other working catheter is introduced through the self-sealing port in parallel to the catheter body <NUM>. The periphery of the self-sealing port <NUM> will be sufficiently compliant (elastic) to conform to and seal against both catheters simultaneously.

<FIG> illustrate a fourth alternative embodiment of an embolic protection device <NUM>. A filter body <NUM> comprises a double layer of mesh throughout most of the filter, with an additional layer or cuff <NUM> (for a total of three layers) at a downstream end to increase the anchoring strength of the filter in this portion of the device. <FIG> shows the embolic protection device <NUM> in its relaxed configuration, while <FIG> show the embolic protection device <NUM> as it is axially stretched in the direction of arrows <NUM> into a delivery or retrieval configuration. Since a self-sealing port <NUM> and other device features are integrally or monolithically formed within a continuous cylindrical mesh structure, these features effectively disappear when the filter body <NUM> is fully stretched out in the axial direction. This ability to stretch out and eliminate internal structure minimizes the device profile. The construction of the filter from one continuous cylindrical surface also avoids manufacturing complexity and maintains a smooth contact surface throughout the device to reduce the friction of procedural tools passing through the filter. The filter body is attached to a deployment catheter body <NUM> by a stent-like peripheral support structure <NUM> which overlaps or overlies a downstream cylindrical chamber <NUM> of the filter body <NUM>. The self-sealing port <NUM> may comprise a conical base <NUM> and a sleeve <NUM> generally as described previously.

<FIG> illustrates the embolic protection device <NUM> deployed over a patient's aortic arch to protect the branch vessels as an interventional catheter is delivered in an upstream direction through the self-sealing port <NUM> to perform a procedure, such as valvuloplasty or TAVR, at the aortic valve AV.

<FIG> shows alternative configurations of the filter body. <FIG> shows a filter body <NUM> comprising an upstream cylindrical chamber <NUM> and a downstream cylindrical chamber <NUM> separated by a simple narrowing or neck <NUM> formed in the cylindrical mesh material. The cylindrical mesh material may be single-walled, double-walled, have more than two layers over some or all of the wall area, or combinations thereof, and this filter body configuration can be combined in most or all of the embodiments of the embolic protection devices described previously.

<FIG> shows a filter body <NUM> comprising an upstream cylindrical chamber <NUM>, a central cylindrical chamber <NUM>, and a downstream cylindrical chamber <NUM> separated by a necks <NUM> and <NUM>, respectively. It will be appreciated that such multiple cylindrical chambers could be separated by any of the self-closing port structures described previously. The downstream end of the downstream cylindrical chamber <NUM> may be gathered or closed, as illustrated, and the filter body <NUM> with a closed downstream end may find particular use in the clot capture configurations described in <FIG> below. As with previous embodiments, the cylindrical mesh material of filter body <NUM> may be single-walled, double-walled, have more than two layers, or be combinations thereof, and multi-chamber filter body configurations can be combined in most or all of the embodiments of the embolic protection devices described previously, although the downstream end of the downstream chamber will have to be opened.

<FIG> shows a filter body <NUM> comprising an upstream cylindrical chamber <NUM>, a central cylindrical chamber <NUM>, and a downstream cylindrical chamber <NUM> separated by a neck <NUM> and a self-sealing port <NUM>, respectively. The downstream end of the downstream cylindrical chamber <NUM> is open, and the multi-chamber filter body <NUM> can be combined in most or all of the embodiments of the embolic protection devices described previously. The cylindrical mesh material of filter body <NUM> may be single-walled, double-walled, have more than two layers, or be combinations thereof.

Claim 1:
A luminal emboli capture device comprising:
a filter body (<NUM>) comprising a tubular porous mesh material having an open upstream end (<NUM>) and an open downstream end (<NUM>), the tubular porous mesh material being preformed so that upon expansion the tubular porous mesh material forms a first, self-sealing, port (<NUM>) spaced inwardly from each of said ends, a downstream open cylindrical chamber (26B) and an upstream open cylindrical chamber (26A), wherein said self-sealing port (<NUM>) comprises a wall portion of the tubular porous mesh material, wherein said self-sealing port comprises an expandable opening configured to conform to at least one working catheter passing therethrough, wherein the downstream open cylindrical chamber(26B) is between a downstream end of the self-sealing port (<NUM>) and the downstream end of the filter body (<NUM>), and wherein the upstream open cylindrical chamber (26A) is between an upstream end of the self-sealing port (<NUM>) and the upstream end of the filter body (<NUM>); and
a catheter body having a distal end coupled to the downstream end of the filter body.