Embolic protection pass through tube

An embolic protection device includes an outer surface that is configured to form a substantially sealed relationship with a body lumen such that emboli are deflected and/or captured by the outer surface before such emboli can travel to other parts of the body. An inner surface of the embolic protection device includes a longitudinally extending lumen through which instrumentation may be inserted, facilitating passage of such instrumentation through the body lumen while minimizing risk to the patient from emboli.

BACKGROUND OF THE INVENTION

The present disclosure generally relates to devices and systems for use within blood vessels, and more particularly to devices and systems for use within blood vessels that deflect and/or trap emboli.

Arterial embolism is a sudden interruption of blood flow to an organ or body part due to an embolus, e.g., debris or a clot. During a medical procedure, thrombi may form and emboli may move, dislodge or break free within arteries. As used herein, the term emboli refers generally to any particles or debris moving within the bloodstream. These emboli are capable of traveling far from their origins, migrating to other sites of the vasculature where they may obstruct the flow of blood. For example, an embolus may travel through the carotid artery and inhibit the flow of blood to the brain, which may result in the death of brain cells, i.e., cause a stroke. Blockage of the carotid arteries is the most common cause of a stroke.

BRIEF SUMMARY OF THE INVENTION

Disclosed herein are embolic protection devices which facilitate passage of instrumentation through a patient's vasculature while minimizing the risk from emboli traveling within a patient's vasculature.

In an embodiment, an embolic protection device may include a tubular sheet having a first end and a second end, and a delivery catheter. The first end of the tubular sheet may be fixedly connected to the delivery catheter, and the second end of the tubular sheet may be translatable through the delivery catheter.

In another embodiment, an embolic protection may have a proximal section, a distal section, and an intermediate section between the proximal and distal sections. The intermediate section may have a first diameter, and the proximal and distal sections may each have a diameter that is greater than the first diameter. The elongated tubular body may be transitionable between an unfolded configuration in which the intermediate section is positioned between the proximal and distal sections, and a folded configuration in which the distal section is inverted over the intermediate section.

In yet another embodiment, an embolic protection device may include a tube formed from a compressible material, and may have a first end, a second end, and a diameter. A wire may operatively couple the first end and the second end of the tube. The wire may be translatable relative to the tube to cause a corresponding movement of the first end of the tube relative to the second end of the tube and a corresponding change in the diameter of the tube.

In a still further embodiment, an embolic protection device may include a tube that is transitionable between a compressed condition and an expanded condition. The first section may have a first diameter. The second section may have a second diameter that is smaller than the first diameter. The first section may include a first lumen through which the second section is translatable. The second section may include a second lumen through which an elongated instrument is insertable.

In a still further embodiment, an embolic protection device may include a tubular member having an outer layer and an inner layer. The inner layer may have a first section with a first diameter, a second section with a second diameter, and an intermediate section with a diameter smaller than the diameters of the first and second sections and positioned between the first and second sections. A lumen may extend continuously through the first section, the second section, and the intermediate section. The lumen may be configured to receive an elongated instrument therethrough.

In yet another embodiment, an embolic protection device may include an elongated tubular body having a longitudinal axis, a first section, a second section, and a third section. The body may be configured to transition between an expanded state and a compressed state, and may be biased toward the expanded state. The second section may be dispoised between the first section and the third section. The second section may be relatively narrower than the first section and the third section in the expanded state. A lumen may extend through the body along the longitudinal axis. The lumen may be sized to receive an elongated instrument therethrough. The elongated instrument may be radially spaced from the outer surfaces of the first and third sections when the instrument is positioned within the lumen.

These and other embodiments of the present disclosure are more fully described hereinbelow.

DETAILED DESCRIPTION

Particular embodiments of the present disclosure are described with reference to the accompanying drawings. In the figures and in the description that follow, like reference numerals identify similar or identical elements. As used throughout the following description, the term “proximal” refers to the end or portion of a device that is relatively close to the user deploying the device, and the term “distal” refers to the end or portion of the device that is relatively farther away from the user deploying the device. As used herein, the term “tube” may refer to any elongated body through which an instrument may be passed, and is not limited to any particular geometric shape, and may be for example, cylindrical or conical in shape.

The aorta is the main trunk of a series of vessels that convey oxygenated blood to the tissues of the body. As shown inFIG. 1, aorta A includes ascending aorta AA, which commences at the upper part of the left ventricle of the heart. After ascending for a short distance, aorta A arches backward and to the left side to form aortic arch AR, which transitions to descending aorta DA, which descends within the thorax. Aortic arch AR commonly includes three arterial branches: brachiocephalic artery B, left common carotid artery LC, and left subclavian artery LS. Brachiocephalic artery B supplies blood to the right arm, the head, and the neck. Typically, brachiocephalic artery B includes a common brachiocephalic trunk, which branches into right subclavian artery RS and right common carotid artery RC. Left common carotid artery LC branches into internal and external vessels near the top of the thyroid, and supplies blood to the brain and other tissues within the skull. Left subclavian artery LS supplies blood to the left arm, with some branches supplying blood to the head and thorax. It is to be understood that the anatomy of a particular individual may differ, and that the description of particular anatomical features is merely illustrative and should not be construed as limiting the disclosure.

A thrombus or blood clot may form within an artery, when blood flow is sluggish, enabling clotting factors to accumulate and giving platelets an opportunity to stick together. An embolus is most often a piece of a thrombus that has broken free. However, an embolus may also be plaque, fat, and other material. An embolus travels with the flowing blood until it reaches a narrowing in the artery through which it cannot pass, blocking the artery. During a vascular procedure, such as a transcatheter aortic valve implantation (TAVI) procedure (also known as transcatheter aortic valve replacement (TAVR) procedure), emboli may be dislodged as surgical instrumentation passes through the vasculature, and, for example, causes plaque to become dislodged or scrapes tissue from the artery during the translation of the instrumentation.

Various embodiments of devices and systems for deflecting and/or capturing emboli are described with reference toFIGS. 2A-15. Embolic protection device100is shown inFIGS. 2A and 2B. Device100includes a tubular sheet101that may be formed from a braided or mesh-like material. The material may have shape memory properties, such as exhibited by a nickel titanium alloy, and may be transitionable between a compressed state and an expanded state. Tubular sheet101has outer surface102aand inner surface102b, one or both of which may be coated with a substance having anti-thrombogenic properties, such as heparin. Tubular sheet101has a fixed end103that is secured at or near the distal end104of a delivery catheter C, and a free end105that is translatable through delivery catheter C. Free end105of tubular sheet101may be operatively coupled to delivery tube106, which is translatable through delivery catheter C, so that movement of delivery tube106may cause a corresponding movement of free end105of tubular sheet101. Instrumentation for performing a surgical procedure may be passed through delivery tube106, as well as through tubular sheet101. The length of tubular sheet101extending from distal end104of delivery catheter C is adjustable by translating free end105of tubular sheet101relative to delivery catheter C. Tubular sheet101will be folded upon itself when deployed such that, when deployed, distal end107of the tubular sheet will be a folded edge. Tubular sheet101may have a heat-set crease preformed at a spaced distance from its free end105. In a fully deployed condition, the crease may define distal end107of the deployed tube. When any portion of tubular sheet101is deployed from delivery catheter C, the width thereof may expand to a width that is greater than the inner diameter of the delivery catheter.

Device100may be deployed within a patient's vasculature using catheter-based techniques to achieve desired placement. The delivery of device100may occur via a transfemoral approach (through the inguinal crease), a transradial approach (through an artery in the arm), or any other percutaneous approach. For example, in a transfemoral approach, delivery catheter C may be maneuvered up through aortic arch AR, and once it is in a desired position, delivery tube106may be pushed through the delivery catheter to cause a corresponding translation of free end105of tubular sheet101in direction A along the delivery catheter. As free end105of tubular sheet101is distally translated, tubular sheet101will evert as distal end107thereof rolls in direction R and the length of the tubular sheet extending from distal end104of delivery catheter C becomes greater. Tubular sheet101may be deployed to its fully expanded condition in which the crease is at distal end107of the deployed tubular sheet or may be deployed by some lesser amount. Advantageously, the rolling motion of distal end107of tubular sheet101during deployment of the tubular sheet minimizes the generation of emboli. As tubular sheet101is deployed from delivery catheter C, it automatically transitions to its expanded state (FIG. 2A) in which outer surface102aof the tubular sheet engages the wall of aortic arch AR in apposition to one or more of arterial branches B, LC, and/or LS (not shown). The curvature of tubular sheet101in the expanded state may correspond to the natural curvature of the aorta, such that the deployed tube fills the cross-section of the aorta. Tubular sheet101is positionable in aortic arch AR (FIG. 1) such that emboli present in the blood flowing through the aortic arch may flow into the interior of the deployed tubular sheet, and are blocked from entering one or more of arterial branches B, LC, and/or LS (FIG. 1). Furthermore, emboli within the flowing blood may be directed through tubular sheet101and into delivery tube106, thereby capturing such emboli.

A surgical instrument, such as a valve delivery catheter, may be inserted through delivery tube106and through the interior of tubular sheet101. After completion of a desired surgical procedure, delivery tube106may be pulled farther into delivery catheter C to cause a corresponding translation of free end105of tubular sheet101in direction B into the delivery catheter (shown inFIG. 2B). As a result, distal end107of tubular sheet101will roll in direction Q as tubular sheet101inverts in the opposite direction and the length of tubular sheet101extending from distal end104of delivery catheter C is decreased. The retraction of tubular sheet101may continue until tubular sheet101is substantially entirely within delivery catheter C.

Another embodiment of an embolic protection device110is shown inFIGS. 3A and 3B. Device110may include a generally cylindrical tube111formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli of a predetermined size are deflected and/or captured before they can enter branches B, LC, and/or LS of aortic arch AR. The material forming tube111may exhibit shape memory properties, such as those exhibited by a nickel titanium alloy or a porous elastic foam, such that the tube is compressible to a smaller size and may be translated through delivery catheter C. As with the previously described embodiments, the components of device110may be coated with a substance having anti-thrombogenic properties. The ends of tube111may be contained within a distal crimp tube112and/or a proximal crimp tube113. One or more of crimp tube112and113may be releasably attachable to wire114, such as via a magnetic connection, a screw connection, a hook and loop type connection or the like. For example, wire114may include magnet115at a distal end thereof, and may be magnetically coupled to one of the crimp tubes112and113.

Device110is deliverable via any percutaneous delivery approach, including a transfemoral delivery approach in which the device is loaded in a compressed condition within delivery catheter C, which is maneuvered within the patient's vasculature toward the aortic arch AR. Deployment of device110may be achieved by pushing wire114, which is operatively coupled to one of distal crimp tube112and proximal crimp tube113, through delivery catheter C. As device110device110is deployed from delivery catheter C, the device expands to frictionally engage the wall of aortic arch AR such that tube110shields one or more of the ostia leading to arterial branches B, LC, and LS. Once device110is deployed, wire114may be disengaged from the crimp tube112or113to which it was coupled. Device110may remain deployed throughout the primary procedure, such as a TAVI procedure. After completing the primary procedure, device110may be retrieved by coupling wire114to one of crimp tubes112or113and drawing the wire into delivery catheter C. For example, wire114may be coupled to proximal crimp tube113and pulled back into delivery catheter C. Alternatively, wire114may be coupled to distal crimp tube112such that, as wire114is retracted into delivery catheter C, tube111is inverted and drawn into the delivery catheter, as illustrated inFIG. 3B. Advantageously, the inversion of tube111may facilitate capture and removal of emboli within the tube as it is being retracted into delivery catheter C.

A still further embodiment of an embolic protection device is shown inFIG. 4. Device120includes tube121having a generally cylindrical configuration with a lumen122extending longitudinally therethrough. Lumen122may have a constant diameter P along substantially the entire length of tube121. Tube121may be formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli greater than a predetermined size are deflected and/or captured before they can enter arterial branches B, LC, and/or LS or aortic arch AR. Crimp tube123may be crimped to at least one of proximal end124and distal end125of tube121to crimp the material forming tube121therein, and may couple tube121to wire W. As with the previously described embodiments, device120may be transitionable between a collapsed condition for insertion into a delivery catheter, and an expanded condition, and preferably is formed from a nickel titanium alloy or other shape memory material that may be coated with a substance having anti-thrombogenic properties. Device120may be biased toward the expanded condition so that, upon deployment from a delivery catheter, it will automatically expand.

Device120may be deployed within a patient's vasculature using catheter-based techniques to achieve desired placement. The delivery of device120may occur via a transfemoral approach, a transradial approach, or any other percutaneous approach. Device120may be compressed and loaded into the delivery catheter in the compressed condition. When the delivery catheter is positioned in or near aortic arch AR, device120may be deployed by pushing wire W through the delivery catheter. In the deployed condition, the distal end of tube121is preferably positioned upstream of brachiocephalic artery B so that the tube covers the ostia leading to one or more of arterial branches B, LC, and LS. Once device120has been deployed, blood flowing in the direction of arrow F, including during a procedure performed upstream of the device, will flow through lumen122of tube121and may flow through the wall of tube121into arterial branches B, LC, and/or LS. Any emboli that are larger than a predetermined size, however, will be deflected away and therefore, prevented from entering arterial branches B, LC, and/or LS by tube121. Elongated instruments T are translatable through lumen122to facilitate performance of a desired procedure, such as a valve repair procedure. Once the desired procedure has been completed, device120may be retrieved by pulling wire W back into the delivery catheter.

In a still further embodiment, as shown inFIG. 5, embolic protection system130may include embolic protection device120and a stiffening device132. Stiffening device132may include a holder133operatively coupled to proximal end124of tube121. Wire134may extend through holder133and through the length of tube121, and may be secured to distal end125of the tube. Holder133may frictionally engage wire134to hold the wire in a given position unless a sufficient force is applied to overcome the frictional force. Helical or coiled strand136may be disposed around wire134, and may be operatively coupled to holder133. Stiffening device132is configured to adjust distance R between proximal end124and distal end125of tube121to cause a corresponding adjustment in the outward radial force exerted by tube121when it is positioned within aortic arch AR. For example, reducing distance R may result in a corresponding increase in diameter Q of tube121, causing tube121to push against the wall of aortic arch AR with a greater force than when tube121is deployed therein without stiffening device132. Rotation of helical strand136may change the pitch of the helix, thereby increasing the rigidity of helical strand136. An increase in the rigidity of helical strand136may facilitate maneuvering and/or stabilizing of tube121within the aortic arch. In addition, as the pitch of helical strand136is increased, the helical strand may exert a compressive force against the material of tube121, which may increase the rigidity of tube121. Moreover, a tensile force may be applied to wire134, resulting in a reduction of distance R and causing tube121to transition toward a larger diameter. By reducing distance R between proximal end124and distal end125, the amount of material per area of the tube is increased, and therefore the rigidity of tube121is correspondingly increased. In so doing, the hoop stress, which is the average force exerted circumferentially, of tube121may be adjusted as desired.

In another embodiment, shown inFIG. 6, embolic protection device140includes an elongated generally cylindrical tube141that may be formed from a material having shape memory properties, such as those exhibited by a nickel titanium alloy. Tube141may be compressible for loading into delivery catheter C, and may be biased toward the expanded state such that, after being compressed, the tube will transition back toward the expanded state. Tube141and the other components of device140may be coated with a substance having anti-thrombogenic properties. Tube141may be formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli of a predetermined size are deflected and/or captured. First portion142of tube141includes opening143, which extends along the length of first portion142and has a fully expanded diameter D. Diameter D is larger than the diameter of aortic arch AR so that, when device140is deployed in aortic arch AR, first portion142will frictionally engage the walls of aortic arch AR. Second portion144of tube141is joined to first portion142and includes inverted portion145, and emboli collection area146. Emboli collection area146is disposed at the proximal end of tube141and includes a narrowed inlet147. Emboli that may enter tube141through opening143may pass through tube141and be collected or trapped within emboli collection area146. Inverted portion145of tube141tapers inwardly toward first portion142to opening148, which has diameter d. Opening148is sized to receive elongated instrument T therethrough, such as a valve delivery catheter, which may be introduced into the patient's vascular system via an incision I1. Inverted portion145of tube141may be generally cone shaped to facilitate insertion of instrumentation through opening148. Second section144may include crimp tube149, which may inhibit the braided material of tube141from unraveling. Crimp tube149may be attached to wire W to facilitate the deployment of device140from delivery catheter C.

The deployment of embolic protection device140may be achieved by loading the device into delivery catheter C in a compressed state, and maneuvering delivery catheter C toward aortic arch AR via a percutaneous access approach. For example, delivery catheter C may be delivered via a transfemoral approach, for example by making an incision12and introducing the delivery catheter into femoral artery FA, and maneuvering the delivery catheter toward aortic arch AR. When delivery catheter C reaches a desired position, wire W may be pushed through delivery catheter C, causing device140to be deployed from delivery catheter C. As device140is deployed, it automatically transitions to its expanded state in which first portion142engages the wall of aortic arch AR in apposition to one or more of arterial branches B, LC, and/or LS. Once device140has been deployed, any blood flowing in the direction of arrow F, including during a procedure performed upstream of the device, will flow into tube141through opening143and out through the mesh-like material at second portion144of tube141. For example, during the TAVI procedure, elongated instrument T, such as a delivery catheter, may be inserted through tube141to access a target site upstream of tube141. Elongated instrument T may be received snuggly within opening148having a diameter d approximately that of elongated instrument T so that emboli flowing within the blood are inhibited from exiting through opening148. Any emboli traveling with the blood flow that are larger than the openings in the mesh-like material will be trapped in emboli collection area146. Once the surgical procedure has been completed, device140may be retrieved by proximally translating wire W to pull device140back into delivery catheter C. As device140is withdrawn into delivery catheter C, it is forced into the compressed condition whereupon delivery catheter C may be removed from the patient.

In yet a further embodiment, shown inFIG. 7, embolic protection device150may include tube151formed from a braided or mesh-like material or from a porous foam through which blood may flow, which tube151may capture and/or deflect emboli larger than a predetermined size before they can enter branches B, LC, and/or LS of aortic arch AR when deployed therein. The material forming tube151may exhibit shape memory properties, such as those exhibited by a nickel titanium alloy or a porous elastic foam, and tube151may be transitionable between a compressed state and an expanded state. Device150may be coated by a substance having anti-thrombogenic properties. Tube151may be compressible to a smaller size for loading into and translation through delivery catheter C, and may transition to the expanded state upon deployment from delivery catheter C. Tube151may have a relatively small diameter for a predetermined length at proximal end152, a relatively large diameter at distal end153, and may taper outwardly from the small diameter section to the large diameter section. A portion of tube151from proximal end152may be folded back and forth upon itself such that the tapered region and a portion of the larger diameter section encircles the smaller diameter section. The smaller diameter section at proximal end152has tubular opening154configured to receive instrumentation, such as a valve delivery catheter, therethrough. Proximal end152of folded tube151may include a plurality of small openings155. Proximal end152of folded tube151includes a fold156configured to permit the flow of blood while minimizing the passage of emboli therethrough. Distal end153of tube151may have a relatively large opening156leading to a hollow interior158. When positioned within catheter C, tube151may be unfolded so that the portion of tube151forming tubular opening154is positioned external to hollow interior158of tube151, and the diameter of tube151may be compressed to fit within the smaller diameter of delivery catheter C. Tube151may be biased toward its folded configuration (as shown inFIG. 7) by being, for example, heat set, and may also be biased toward its expanded condition (as shown inFIG. 7) so that tube151may automatically assume its expanded and folded configuration upon deployment from delivery catheter C. The depth to which fold156is positioned within hollow interior158may thus be predetermined and automatically assumed upon deployment of tube151.

A filter material (not shown), such as a polymer or a polyurethane foam, may be secured, e.g., stitched, to the mesh-like material forming tube151to facilitate capture of emboli therein. The filter material may line the interior of tube151. A crimp tube159may crimp the material forming tube151at its proximal end152. Crimp tube159may facilitate coupling of device150to wire W.

Deployment of device150may be achieved in substantially the same manner as described above with respect to the other protection devices. For example, device150may be delivered via a transfemoral approach by loading the device into delivery catheter C in a compressed condition, and maneuvering delivery catheter C up through the aortic arch. When delivery catheter C is positioned as desired within the patient's vasculature, wire W may be distally translated through delivery catheter C to push device150therefrom. As device150is deployed from delivery catheter C, device150may automatically expand to its expanded state. Device150may be positioned close to ascending aorta AA, upstream with respect to arterial branches B, LC, and/or LS, with proximal end152thereof positioned closer to descending aorta DA. In the deployed condition, emboli larger than a predetermined size flowing within the bloodstream into hollow interior158will be unable to pass through small openings155at proximal end152of tube151. Device150may remain deployed within the aortic arch during the course of a primary procedure, such as a TAVI procedure. Instrumentation used for performing the primary procedure may pass through opening154and through hollow interior158of tube151.

Once the primary procedure has been completed, device150may be retrieved. During retrieval of device150, wire W may be pulled through delivery catheter C to retrieve and compress tube151through delivery catheter C. As tube151is retrieved into delivery catheter C, proximal end152of tube151is compressed within delivery catheter C. Continued pulling of tube151into delivery catheter C causes tube151to unfold and become compressed within delivery catheter C. During retrieval of tube151into delivery catheter C and until tube151is substantially retrieved, distal end153may remain substantially engaged with the wall of aortic arch AR so that emboli within the blood flowing through aortic arch AR are directed toward proximal end152of tube151and into delivery catheter C. In so doing, any emboli present in the blood are drawn into and collected within delivery catheter C.

Yet another embodiment of embolic protection device160is shown inFIG. 8. Device160includes tube161which may be formed from a braided or mesh-like material or from a porous foam through which blood may flow, which tube161may deflect and/or capture emboli larger than a predetermined size before they can enter branches B, LC, and/or LS of aortic arch AR when deployed therein. The material forming tube161may exhibit shape memory properties, such as those exhibited by a nickel titanium alloy or a porous elastic foam, and tube161may be transitionable between a compressed state and an expanded state. Device160may also be coated with a substance having anti-thrombogenic properties.

Tube161may be compressible to a smaller size for loading into and translation through a delivery catheter C, and may transition to the expanded state upon deployment from delivery catheter C. Tube161may be loaded into delivery catheter C in a compressed condition in an unfolded condition in which the portion of tube161defining channel165will be retrieved before the remainder of tube161. Tube161may include an outer surface162and an inner surface163. The spacing between outer surface162and inner surface163may be relatively wider along a first length of tube161, and relatively narrower along a second length of the tube. The relatively narrower portion of tube161may be folded to form fold164, with the folded portion forming channel165that extends substantially along the entire length of tube161in this folded configuration. The relatively wider portion of tube161may have hollow interior166having a generally annular configuration, as shown inFIG. 8. A filter material may line an interior of hollow interior166to facilitate capture of emboli that may pass through tube161. At distal end167of tube161, one or more openings168may be formed in the tube and may lead to hollow interior166. A plurality of openings169may be formed at proximal end170of tube161and lead to hollow interior166. Openings168at distal end167of tube161may be larger than openings169at proximal end170of the tube so that emboli within the flowing blood may enter into hollow interior166but will be prevented from exiting through the relatively small openings169. Crimp tube171may crimp the material forming tube161at proximal end170thereof, and wire W may be coupled to crimp tube171.

Deployment of device160may be achieved in substantially the same manner as described above with respect to device150. For example, device160may be loaded into delivery catheter C in an unfolded condition and a compressed condition in which the diameter of the device approximates that of the catheter. Once device160is loaded within delivery catheter C, the catheter may be maneuvered up through aortic arch AR.

When delivery catheter C is positioned as desired within the patient's vasculature, wire W may be distally translated through delivery catheter C to push device160therefrom. As device160is deployed from delivery catheter C, the device may automatically expand to its expanded state. Device160may be positioned closer to ascending aorta AA, upstream with respect to arterial branches B, LC, and/or LS, with proximal end170thereof positioned closer to descending aorta DA. An instrument may be inserted through channel165, which may approximate the diameter of the instrument inserted therethrough. When device160is deployed, any emboli within the bloodstream will be directed through openings168and into hollow interior166of tube161. The relatively small size of openings169will prevent emboli larger than a predetermined size from exiting hollow interior166. Device160may remain deployed within the aortic arch during the course of a primary procedure, such as a TAVI procedure. Instrumentation used during the primary procedure may pass through channel165.

In a further embodiment, shown inFIG. 9, embolic protection device180includes elongated tube181having proximal end182, distal end183, and hollow interior184extending along the length of tube181. Tube181may be formed from the same materials described above with respect to the other embodiments. In particular, tube181may be formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli of a predetermined size are deflected and/or captured before they can enter branches B, LC, and/or LS of aortic arch AR. Tube181may be formed from a material having shape memory properties, such as those exhibited by a nickel titanium alloy or a porous elastic foam, so that tube181is compressible to a smaller size that enables it to be inserted into and translated through delivery catheter C. As with the other devices described herein, tube181and the other components of device180may be coated with a substance having anti-thrombogenic properties. Proximal end182of tube181may include an opening185leading to hollow interior184. Opening185may be angled with respect to the longitudinal axis of tube181. Filter186having a disc-like shape may be disposed in and may substantially close distal end183of tube181. Filter186may be formed from a polymer, such as a polyurethane foam, from a sufficiently porous fabric material, or from other similar types of materials capable of providing a filtering function. Filter186may be transitionable between an expanded condition and a compressed condition so as to be compressible along with the rest of device180. Opening187in filter186is sized to snugly receive therethrough instruments T for performing a desired procedure. One such instrument T may be preloaded within device180prior to the deployment of device180or may be introduced subsequent to the deployment of device180so that the instrument passes through opening185, hollow interior184, and opening187in filter186. Crimp tube188may be crimped to an edge of tube181at proximal end182to hold the free ends of the material forming tube181together. Crimp tube188may also couple tube181to wire W to facilitate deployment of device180into the patient's vasculature.

Deployment of device180may be achieved by any suitable percutaneous approach. For example, device180may be delivered via a transfemoral approach by loading the device into delivery catheter C in a compressed condition, and maneuvering delivery catheter C up through aortic arch AR. When delivery catheter C is positioned as desired within the patient's vasculature, wire W may be distally translated through delivery catheter C to push device180therefrom. As device180is deployed from delivery catheter C, tube181automatically radially expands to its expanded state. In the expanded state, tube181contacts the wall of aortic arch AR to frictionally secure device180therein. Device180may be positioned in aortic arch AR with distal end183positioned closer to ascending aorta AA, upstream with respect to one or more ostia leading to arterial branches B, LC, and/or LS, and proximal end182positioned closer to descending aorta DA. Instruments T, such as a valve delivery catheter, may be inserted and translated through the hollow interior184of tube181and through opening187in filter186. As blood flows through the aorta in the direction of arrow F, filter186inhibits the passage of emboli both into one or more of arterial branches B, LC, and/or LS, and downstream of device180. Once the desired procedure has been completed, device180may be retrieved by pulling wire W back through delivery catheter C, which forces the device to its compressed state and repositions it within delivery catheter C for removal from the patient.

Yet another embodiment of embolic protection device, device190shown inFIG. 10, is substantially similar to device180described above with the exception that device190includes a tube191having a substantially conical configuration. As with the other embodiments, device190may be transitionable between a collapsed condition for insertion into delivery catheter C, and an expanded condition, and preferably is formed from a nickel titanium alloy or other shape memory material that may be coated with a substance having anti-thrombogenic properties. Tube191has a distal end192and proximal end193and hollow interior194within tube191. Tube191may be formed from the same materials discussed above with respect to tube181of device180. The diameter of tube191at distal end192preferably is greater than the diameter of aortic arch AR so that, upon deployment of device190, the distal end expands into secure frictional engagement with aortic arch AR to hold device190in place against blood flow.

Filter195, which may be substantially similar to filter186, may be disposed in and may substantially close distal end192of tube191. As with filter186, filter195may include aperture196for the reception of instrument T therethrough. Aperture197formed in the sidewall of tube191leads to hollow interior194, and is configured and adapted to receive instrument T therethrough. One such instrument T may be preloaded within device190or may be placed within device190after its deployment so that instrument T passes through aperture197, hollow interior194, and opening196formed within filter195. An edge of tube191at proximal end193may be crimped within crimp tube198. Crimp tube198may couple tube191to wire W.

Deployment and retrieval of device190is substantially similar to that described above with respect to device180. When deployed within aortic arch AR, distal end192of device190may be positioned upstream of an ostium leading to one of aortic branches B, LC, or LS. Filter195inhibits the passage of emboli through aortic arch AR. The cone-like configuration of tube191may minimize contact between tube191and the wall of the aortic arch, which may be advantageous if the wall of the aorta is fragile. In addition, by minimizing contact between tube191and the wall of aortic arch AR, distortion of the shape of the tube that might occur if such contact were to take place may be minimized.

In a still further embodiment, embolic protection device200is shown inFIG. 11. Device200includes tube201that has first section202, second section204, and middle section206disposed therebetween. Tube201may define an hour-glass shape such that first section202and second section204have relatively large diameters that taper downwardly or narrow as they approach middle section206. The interior of tube201may be hollow such that instrument T may be translated through first section202, middle section206, and second section204. Tube201of device200may be formed from a braided mesh-like material having shape memory properties, such as those exhibited by a nickel titanium alloy, such that the device may be transitionable between a compressed state and an expanded state. As with the other devices described herein, tube201and the other components of device200may be coated with a substance having anti-thrombogenic properties. Blood may flow through the mesh-like material of tube201, while emboli of a predetermined size are deflected and/or captured. An end of one of first section202or second section204may be contained within crimp tube208, which may inhibit the braided material of device200from unraveling. Wire W may be coupled to crimp tube208to facilitate deployment and/or retrieval of device200through delivery catheter C.

Device200may be deployed within a patient's vasculature using the same percutaneous delivery approaches described above with respect to the other embodiments. For example, device200may be delivered via a transfemoral delivery approach in which the device is loaded into delivery catheter C in a compressed condition so that it can fit within delivery catheter C. In particular, device200may compress in a radial direction such that its width becomes narrower. In that regard, the axial length of device200may correspondingly increase. Once delivery catheter C has been positioned at or near the desired location in the patient's vasculature, device200may be deployed by pushing wire W out from the delivery catheter, whereupon it will expand to its normal expanded state (as shown inFIG. 11) from a compressed state in which the diameter of tube201has been reduced to fit within delivery catheter C.

In the deployed condition, shown inFIG. 11, device200is positioned within aortic arch AR such that instruments T may be translated through tube201. The tapered middle section206spaces instruments T away from the wall of aortic arch AR such that forces applied by instruments T upon the wall of aortic arch AR are minimized, and the interaction between middle section206of tube201and aortic arch AR is minimized. First section202and second section204may frictionally engage the wall of aortic arch AR, thereby minimizing the flow of blood between device200and the wall of the aortic arch. Since middle section206has a narrowed diameter relative to that of first section202and second section204, middle section206may be isolated from the wall of aortic arch AR such that the openings between the braided material forming middle section206are substantially unaffected by interaction with aortic arch AR. Device200may remain deployed throughout the primary procedure. After completing the primary procedure, device200may be retrieved by pulling wire W back into delivery catheter C, which causes device200to be compressed within the delivery catheter such that it can be removed from the patient as delivery catheter C is withdrawn. Emboli may be trapped within the interstices between the braided material forming tube201. Additionally, a filter material (not shown) may line tube201such that emboli coming in contact with the filter material may be trapped therein.

Yet another embodiment of embolic protection is shown inFIGS. 12A and 12B. Device210includes tube211, which may include distal portion212, proximal portion213, and intermediate portion214disposed between distal portion212and proximal portion213. Device210may be formed from the same materials described above in connection with device200. That is, tube211may be formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli of a predetermined size are deflected and/or captured, and may be coated with a substance having anti-thrombogenic properties. The material forming tube211may have shape memory properties, such as exhibited by a nickel titanium alloy or a porous elastic foam, such that tube211is transitionable from a normally expanded state to a compressed state in which it is positionable within delivery catheter C. Tube211may have somewhat of an hour-glass configuration with a relatively large diameter at distal portion212and proximal portion213, and a relatively small diameter in intermediate section214. The diameters of distal portion212and proximal portion213remain substantially constant for a predetermined length of the tube, as does the diameter of intermediate section214. The diameter of tube211gradually tapers downward from distal portion212and proximal portion213toward intermediate section214. Tube211includes a hollow interior215. Crimp tube216may contain a proximal end of tube211, and may couple tube211to wire W. Another crimp tube217may contain a distal end of tube211, and may couple tube211to wire W2.

As shown inFIG. 12B, distal portion212of tube211may be everted and rolled back over intermediate section214. As a result, tube211in this folded condition has a substantially constant diameter at its proximal end corresponding to proximal portion213of the unfolded tube. When in this folded condition, the distal end of tube211is folded over upon and covers the region of intermediate section214that tapers to a smaller diameter from the proximal end of tube211toward the distal end of tube211. When in this folded condition, the substantially constant diameter of distal portion212of tube211surrounds the smaller diameter of intermediate section214. Thus, by rolling distal portion212of tube211back over the intermediate section214, a relatively small diameter opening219extending through tube211is formed. Proximal portion213of tube211may have a hollow interior215that tapers inwardly along its length from the substantially constant diameter portion to the relatively small diameter opening219at which it joins intermediate section214. The diameter of opening219is sized so as to receive therethrough instruments T for performing the desired procedure.

Filter218may be operatively coupled to the distal end of tube211. For example, filter218may be stitched within a portion of distal portion212so that when distal portion212is folded filter218is at the distal end of device210, as shown inFIG. 12B. Filter218may include an opening (not shown) that is aligned with opening219through tube211. Filter218may be disposed within tube211to protect filter218from damage. Filter218may be formed from a material that will allow blood to flow therethrough while inhibiting the passage of emboli as the blood flows through the aorta in the direction of arrow F. For example, filter218may be formed from a polymer, such as a polyurethane foam, a sufficiently porous fabric material, or other similar types of materials capable of providing a filtering function. A filter material may be operatively coupled to or integrated into the mesh-like material forming tube211along substantially the entire length of tube211or along substantially the entire length of distal portion212of tube211.

Deployment of device210may be achieved by compressing the device in the folded condition and loading it into delivery catheter C. In the compressed condition, the width or radial dimension of device210is narrower than in the expanded condition. Delivery catheter C may be delivered via a transfemoral approach and maneuvered toward aortic arch AR. Once delivery catheter C is at a desired position in the patient's vasculature, wire W may be distally translated through delivery catheter C. As wire W moves distally, device210is pushed out from delivery catheter C and expands to its expanded configuration, as shown inFIG. 12A, to radially contact the wall of aortic arch AR. The distal end of device210may be positioned upstream of one or more ostia leading to arterial branches B, LC, and/or LS to minimize/prevent the passage of emboli therethrough.

After deploying device210into aortic arch AR, wire W2may be proximally drawn into catheter C to cause distal portion212to fold proximally over intermediate section214. Device210may be biased toward a expanded condition and may automatically transition to its expanded condition upon deployment. With device210expanded so as to fill the cross-section of aortic arch AR, elongated instrument T, such as a valve delivery catheter, may be guided through hollow interior215of proximal portion213and through opening219so as to reach the target site. The tapered shape of proximal portion213may facilitate a desired spacing of such instrumentation from the walls of the aortic arch. At this juncture, any blood flowing in the direction of arrow F, including during a procedure performed upstream of device210, will pass through the mesh-like material of distal portion212and through the mesh-like material of proximal portion213, then out from device210through hollow interior215at the proximal end of device210. Emboli may be trapped by the mesh-like material of distal portion212or by a filter disposed on or within distal portion212, such as filter218. Once the subsequent procedure has been completed, device210may be retrieved by translating wire W and/or wire W2proximally to pull the device into delivery catheter C. As device210is withdrawn into delivery catheter C, tube211may be forced into a compressed condition as it engages the wall of catheter C, in which it has a reduced diameter so that tube211may be loaded into catheter C. Once retrieved into catheter C, device210along with any emboli captured therein may be removed from the patient as catheter C is withdrawn from the patient.

In a still further embodiment, shown inFIG. 13, embolic protection device220includes tube221having distal section222having inner diameter G, middle section223configured to snuggly receive instrument T, and proximal section224which may have a diameter that tapers toward middle section223. Proximal section224may have an inner diameter that narrows in the fully expanded condition from its free end toward inner diameter N of middle section223. Inner diameter N of middle section223may approximate the diameter of instrument T. The tapered shape of proximal section224may facilitate guiding elongated instrument T into and through middle section223. As with the previously described embodiments, device220may be transitionable between a collapsed condition for insertion into a delivery catheter, and an expanded condition, and preferably is formed from a nickel titanium alloy or other shape memory material. Also, as with the previously described embodiments, device220may be coated by a substance having anti-thrombogenic properties. Distal section222and proximal section224of tube221may have a substantially uniform inner diameter G in the fully expanded condition. When fully expanded, device220preferably has an outer diameter that is larger than the diameter of the aorta so that, upon deployment, the device may securely engage the wall of the aorta to hold the device in place. Crimp tube225may be crimped to the material forming tube221at the proximal end thereof and may couple the tube to wire W.

The delivery, deployment and retrieval of device220may be accomplished in the manner described above in connection with the other embodiments. In the deployed condition, distal end226of tube221may be positioned upstream relative to one or more of arterial branches B, LC, and LS. As such, blood flowing in direction F passes through the mesh of middle section223and through the mesh of tube221. The wall of tube221deflects emboli larger than a predetermined size from entering arterial branches B, LC, and/or LS, and middle section223prevents emboli larger than a predetermined size from passing through device220toward descending aorta DA. Accordingly, emboli present in the blood may collect within distal section222. Device220therefore inhibits passage of emboli both through aortic arch AR, as well as into arterial branches B, LC, and/or LS.

Yet another embodiment of embolic protection device230is shown inFIGS. 14A and 14B. Device230includes tube231formed from a porous foam or from a braided, mesh-like material. Tube231may have shape memory properties, such as exhibited by a nickel titanium alloy or a porous elastic foam, and may be biased toward an expanded state such that, after being compressed, the material will transition back toward the expanded state. As with the previously described embodiments, the components of device230may be coated with a substance having anti-thrombogenic properties. Tube231may have outer surface232and inner surface233, and hollow space234may be disposed between outer surface232and inner surface233. Inner surface233of device230may include first section235and second section236that taper toward a relatively narrow lumen237through which an instrument may be inserted. Narrow lumen237is positioned between first section235and second section236. Inner surface233of first section235of tube231may include a plurality of pores229. Outer surface232of tube231may include a plurality of pores238, and inner surface233of tube231may include a plurality of pores239at the downstream end of tube231. Device230may be placed within the aortic arch such that blood flows from first section235toward second section236. Preferably, emboli within the flowing blood may enter hollow space234but are inhibited from exiting. In that regard, pores229at the upstream end of device230may be larger than pores239at the downstream end of device230. In addition, pores238which permit blood to flow to the arterial branches may be smaller than pores229to inhibit passage of emboli to those branches. Thus, emboli within the flowing blood may pass through pores229into hollow space234and may be inhibited from exiting hollow space234through pores238and/or239. Lumen237may be substantially closed in the absence of an instrument inserted therein, and the diameter of lumen237may approximate that of the instrument when the instrument is inserted therein so that emboli within the flowing blood may be inhibited from entering lumen237when device230is deployed and are instead directed into hollow space234, as described above. One end of device230may be coupled to a crimp tube227to contain the loose ends of braided material therein, and to facilitate coupling device230to wire W.

Device230may be deployed via the percutaneous delivery approaches described above with reference to the other embolic protection device embodiments. Device230may be loaded within a delivery catheter, which may be maneuvered toward the aortic arch AR. Once at a desired position within the patient's vasculature, device230may be deployed by pushing wire W out from the delivery catheter. As device230is deployed, tube231may automatically expand and frictionally contact the wall of aortic arch AR. In the deployed condition, one or more of the ostia leading to arterial branches B, LC, and LS are shielded by device230, thus minimizing the potential of emboli passing into those arterial branches. When tube231is placed in apposition with the wall of aortic arch AR, emboli larger than a predetermined size that are within blood flowing through the aortic arch may be directed into hollow space234, as described above, and may be trapped therein. Device230may remain deployed throughout the course of the primary procedure, such as a TAVI procedure. Once the primary procedure has been completed, device230may be retrieved by pulling wire W back through the delivery catheter.

In still a further embodiment, embolic protection device240is shown inFIG. 15. Embolic protection device240may be formed from a braided or mesh-like material or from a porous foam through which blood may flow while emboli of a predetermined size are deflected and/or captured before they can enter branches B, LC, and/or LS of aortic arch AR. The material forming device240may exhibit shape memory properties, such as those exhibited by a nickel titanium alloy or a porous elastic foam, such that the device is compressible to a smaller size that may be translated through a delivery catheter. As with the previously described embodiments, the components of device240may be coated with a substance having anti-thrombogenic properties.

Device240may include a tubular structure having outer layer241and inner layer242. Inner layer242and outer layer241may be formed by folding a tube into itself so that the tube inverts, thereby forming the outer and inner layers. Outer layer241may have first diameter E and a length d1, e.g., about 8-12 cm, in an expanded condition. Inner layer242may be divided into first section243, second section244, and third section245. First section243and third section245of inner layer242may have a diameter j that approximates the diameter E of outer layer241. First section243may have a generally cylindrical opening246. Second section244may be disposed between first section243and third section245, and may include a longitudinally extending lumen247, which has second diameter g, for the reception of an elongated instrument therethrough. Third section245may include an aperture245afor the reception of the instrument therethrough. A surgical instrument is insertable through first section243, second section244, and third section245. Lumen247may be transitionable between an expanded condition and a compressed condition so that when an instrument is inserted therethrough, lumen247may approximate the diameter of the instrument. At second section244, inner layer242may be substantially evenly spaced from outer layer241. Thus, when an instrument is inserted through second section244, it may be spaced by substantially the same radial distance from outer layer241. First section243may have length d2, second section244may have length d3, and third section245may have length d4, in which length d2is less than the length d3, which is less than length d4. For example, d2may be about 1-2 cm, d3may be about 2-3 cm, and d4may be about 5-7 cm.

The narrowed, second diameter g of second section244is dimensioned such that the second section244may conform to and approximate the diameter of an elongated instrument inserted therethrough. First tapered portion248may be positioned between first section243and second section244. Second tapered portion249may be positioned between second section244and third section245. Tapered portions248and249may facilitate insertion of an elongated instrument through the interior of second section244. Advantageously, the positioning of second section244at a distance away from outer layer241may minimize the potential that an elongated instrument translated through device240may damage the wall of aortic arch AR.

Filter250may be disposed or secured within tapered section248between first section243and second section244. Filter250may facilitate capture and/or deflection of emboli within blood flowing through into device240from first section243. Filter250may be a relatively thin membrane having a disk like configuration formed from a material capable of performing a filtering function, such as a porous polymer. Filter250may be transitionable between a normally expanded state and a compressed state, and may include a throughhole251to facilitate insertion of an elongated instrument therethrough. Crimp tube252may contain the loose ends of the material of third section245therein, and may be operatively coupled to wire W.

Device240may be deployed via any suitable percutaneous delivery approach as may be employed by the devices described hereinabove. For example, device240may be delivered via a transfemoral approach in which the device is loaded into a delivery catheter that is then maneuvered up to aortic arch AR. Device240is deployed from the delivery catheter by pushing wire W through the delivery catheter. In the deployed condition, device240may be positioned within aortic arch AR so as to shield one or more of the ostia leading to arterial branches B, LC, and LS of aorta A, thereby inhibiting emboli from entering these arterial branches. Preferably, first section243may be placed upstream relative to the brachiocephalic artery B to minimize the flow of emboli into each of the arterial branches B, LC, and LS. Device240may be left in such a position throughout the performance of a primary procedure, such as a TAVI procedure. Once the primary procedure has been performed, device240may be retrieved by pulling wire W back into the delivery catheter.

It will be appreciated that the various dependent claims and the features set forth therein can be combined in different ways than presented in the initial claims. It will also be appreciated that any individual features described in connection with any embodiment may be shared with others of the described embodiments. The alternative embodiments presented hereinabove are not mutually exclusive, but may be implemented in various combinations to achieve unique advantages. As these and other variations and combinations of the features discussed above can be utilized without departing from the invention as defined by the claims, the foregoing description of the embodiments should be taken by way of illustration rather than by way of limitation.

By way of illustration only, the embolic protection devices described herein may include a tubular sheet having a first end and a second end; and a delivery catheter, the first end of the tubular sheet being fixedly connected to the delivery catheter, and the second end of the tubular sheet being translatable through the delivery catheter; and/or translation of the second end of the tubular sheet into the delivery catheter progressively may invert the tubular sheet to retract the tubular sheet into the delivery catheter; and/or translation of the second end of the tubular sheet out from the delivery catheter progressively everts the tubular sheet to deploy the tubular sheet from the delivery catheter; and/or may include an elongated delivery rod disposed for sliding movement within the delivery catheter, the second end of the tubular sheet may be operatively coupled to the delivery rod so that sliding movement of the delivery rod in a proximal direction retracts the tubular sheet into the delivery catheter and sliding movement of the delivery rod in a distal direction deploys the tubular sheet from the delivery catheter.

The embolic protection devices may further include an elongated tubular body having a proximal section, a distal section, and an intermediate section between the proximal section and the distal section, the intermediate section having a first diameter and the proximal and distal sections each having a diameter that is greater than the first diameter, the elongated tubular body being transitionable between an unfolded configuration in which the intermediate section is positioned between the proximal and distal sections and a folded configuration in which the distal section is inverted over the intermediate section; and/or including a filter material disposed in the distal section.

The embolic protection devices may also include a tube formed from a compressible material, the tube having a first end, a second end, and a diameter; and a wire operatively coupling the first end and the second end of the tube, the wire being translatable relative to the tube to cause a corresponding movement of the first end of the tube relative to the second end of the tube and a corresponding change in the diameter of the tube.

The embolic protection devices may also include a tube transitionable between a compressed condition and an expanded condition and including a first section having a first diameter and a second section having a second diameter, the second diameter being smaller than the first diameter, the first section including a first lumen through which the second section is translatable, the second section including a second lumen through which an elongated instrument is insertable; and/or the first section may have a hollow interior; and/or may include at least one opening positioned between the first section and the second section, the at least one opening may be sized to permit passage of emboli of a predetermined size into the hollow interior.

The embolic protection devices may further include a tubular member having an outer layer and an inner layer, the inner layer having a first section with a first diameter, a second section with a second diameter, and an intermediate section positioned between the first section and the second section, the intermediate section having a diameter smaller than diameters of the first and second sections, wherein a lumen extends continuously through the first section, the second section, and the intermediate section, the lumen being configured to receive an elongated instrument therethrough; and/or a filter may be disposed within the first section; and/or the elongated instrument may have a diameter, and the diameter of the intermediate section may be about equal to the diameter of the instrument; and/or the tubular member may be operatively coupled to a wire; and/or the tubular member may be coated with an anti-thrombogenic substance; and/or tubular member may be formed from a braided material; and/or the tubular member may have an upstream end, a downstream end, and a plurality of openings, the openings at the upstream end being larger than the openings at the downstream end.

The embolic protection devices may also include an elongated tubular body having a longitudinal axis, a first section, a second section, and a third section, the body being configured to transition between an expanded state and a compressed state, and being biased toward the expanded state, the second section being disposed between the first section and the third section, the second section being relatively narrower than the first section and the third section in the expanded state; and a lumen extending through the body along the longitudinal axis, the lumen being sized to receive an elongated instrument therethrough, the elongated instrument being radially spaced from outer surfaces of the first section and the third section when the elongated instrument is positioned within the lumen; and/or the tubular body may be formed form a braided alloy; and/or may include a filter material lining the tubular body.