Patent Publication Number: US-2016235515-A1

Title: Embolic Protection Device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This PCT application claims the benefit of U.S. provisional application No. 61/893,331, filed on Oct. 21, 2013. This document is incorporated herein by reference 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     This application relates to embolic protection devices and closed-heart surgical procedures using these devices. 
     BACKGROUND OF THE INVENTION 
     During percutaneous cardiac procedures, precise positioning of various instruments and devices can be important. For example, when performing a percutaneous valve replacement procedure, the valve is generally placed no more than 4-6 millimeters (mm) below the lower border of the aortic annulus. Placing the valve prosthesis too low or too high can result in severe leaking of the valve, which in some cases can be fatal. Therefore, it can be important to identify the lower border of the annulus to use as a reference point. A pigtail catheter may be used to inject a contrast agent to allow for visualization for proper positioning. Pigtail catheters may include a coiled distal portion and a plurality of small holes in the catheter side walls. The small holes allow for the introduction of contrast materials into the body for imaging purposes or drainage of fluids from the body. The coiled distal portion helps hold the catheter in place and can slow the flow of contrast fluids from the catheter lumen to avoid causing internal injuries or poor imaging results. 
     A potential complication of cardiac procedures such as valve replacement and repair is that plaque, calcium, and/or thrombi in the vessels, valves, and/or cardiac chambers can be dislodged and cause an embolism. Approximately 2.9%-6.7% of patients undergoing transfemoral transcatheter aortic-valve implantation (TAVI) have a stroke within 30 days, and even more (4.5%-10.6%) have a stroke within a year, often leading to death. Furthermore, up to 85% of patients undergoing TAVI have evidence of embolic phenomenon to the brain based on neuroimaging studies. Although clinically silent, it can be associated with cognitive decline (Astraci 2011; Ghanem 2010; Kahlert 2010; Rodes-Caban 2011). There are a few devices on the market designed to protect the brain, abdominal organs, and carotid arteries from emboli; however, these devices have various disadvantages. For example, the Embrella Embolic Deflector®, available from Edwards Lifesciences of Irvine, California, deflects emboli from the carotid arteries into the descending aorta, but does not trap the emboli, so there is a risk of embolisms in other areas of the body. The EMBOL-X®, also available from Edwards Lifesciences, employs a filtering screen, but it is designed for use in open heart procedures, which present additional medical risks and increased morbidity. Additionally, the use of multiple devices, for example a catheter for visualization and a separate filter device, lengthens the procedure time and increases the risk of complications to the patient. 
     SUMMARY OF THE INVENTION 
     These and other needs are met by the present invention, which is directed to an embolic protection device comprising a deployable embolic filter that is disposed around a catheter having a distal portion that can assume an arcuate configuration being at least a semi-circle. 
     The combination of the catheter and the embolic filter in the same device may provide the benefits of both devices individually, as well as provide a synergistic effect. For example, the integration of the catheter and the embolic filter can decrease the duration of the medical procedure and reduce complications. In other examples, the expansion of the embolic filter may help to anchor the catheter into position to provide a more accurate position of the catheter than if the position of the catheter could be influenced by blood flow, tissue movement, and the like. In a valve replacement procedure, anchoring of the catheter and more accurate positioning of the catheter may in turn help ensure that the valve prosthesis is properly positioned and stabilized. For another example, the position of the catheter may ensure that the filter is being properly positioned. 
     In some aspects, the embolic protection device comprises a multi-lobed self-expanding embolic filter having two or more lobes that is coupled to a catheter and an outer sheath movable with respect to the embolic filter and the catheter. The outer sheath holds the embolic filter in a collapsed configuration when surrounding the embolic filter and is proximally retracted to deploy the embolic filter. The outer sheath may recapture the embolic filter and any debris captured therein by being distally advanced. The filter and outer sheath might both be movable with respect to the catheter, for example to be able to move the embolic filter longitudinally without having to move the entire catheter longitudinally. An embolic filter comprising two or more lobes is advantageous because of the ease in manufacturing and its ability to more fully engage the body lumen when in the expanded configuration. 
     In some aspects, the catheter has a proximal end and a distal end. A lumen extends from the proximal end of the catheter to the distal end of the catheter. In some embodiments, the lumen may be configured to house a guidewire. 
     In some aspects, the catheter is a pigtail catheter. A pigtail catheter is configured to curl at the distal end of the catheter, forming a generally arcuate shape that is at least a semi-circle. The pigtail may have a radiopaque marker viewable on x-rays or other medical imaging devices. The radiopaque marker is on the distal section of the curled pigtail in the form of a longitudinal marker, multiple bands, or the like. The pigtail may additionally have one or more apertures to dispense drugs and/or contrast agents through the lumen 
     In some aspects, a guidewire is inserted through the patient&#39;s skin and into a body lumen such as a femoral, radial, or brachial artery and steered near a target site. The guidewire is inserted into a lumen of the embolic protection device, and the embolic protection device is pushed or tracked over the guidewire to the target site. When the guidewire is retracted from at least the distal portion of the catheter, the catheter assumes a generally arcuate shape. The radiopaque marker on the catheter is used to visualize and position the catheter. Once the catheter is in position, the outer sheath is retracted to deploy the embolic filter across the vessel. The user can then perform a procedure such as valve replacement, valve repair, radio frequency ablation, and the like. When the procedure is completed, the outer sheath is advanced to recapture the embolic filter and any debris trapped in the embolic filter. The device is then retracted, with the catheter being atraumatic to vessels during retraction. 
     Another aspect is a method of capturing embolic debris during a closed-heart surgical procedure comprising inserting the distal end of the catheter of the embolic protection device into a body lumen. The method further comprises allowing the multi-lobed embolic filter to assume an expanded, deployed configuration having a distal opening that spans the body lumen. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The following figures are provided by way of example and are not intended to limit the scope of the claimed invention. 
         FIGS. 1A-1B  show partial side views of one embodiment of an embolic protection device. 
         FIG. 1C  shows a transverse cross sectional view of one embodiment of a multi-lobed embolic filter. 
         FIG. 1D  shows a partial side view of one embodiment of a frame of a multi-lobed embolic filter. 
         FIGS. 2A-2B  show partial side views of one embodiment of an embolic protection device. 
         FIGS. 3A-3D  show partial side views of one embodiment of an embolic protection device. 
         FIGS. 4A-4C  show partial side views of one embodiment of an embolic protection device. 
         FIGS. 5A-5D  show one embodiment of a method of capturing embolic debris using an embolic protection device. 
         FIG. 6  shows one embodiment of a method of deflecting and capturing embolic debris using an embolic protection device. 
         FIG. 7  shows one embodiment of a method of deflecting and capturing embolic debris using an embolic protection device. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is directed to embolic protection devices and methods of capturing embolic debris during surgical procedures. 
     I. Definitions 
     As used herein, the term “closed-heart” refers to any surgical procedure involving the heart, wherein the chest cavity is not opened. 
     As used herein, the term “woven” refers to any material that comprises a plurality of strands, wherein the strands are interlaced to form a net, mesh, or screen. Without limitation, examples of woven materials include netting or mesh comprising a polymer, metal, or metal alloy. 
     As used herein, the term “non-woven” refers to any material that comprises a continuous film. Non-woven material may be permeable, semi-permiable, or non-permeable. For example, permeable or semi-permeable non-woven material may optionally include one or more pores through which a fluid may pass. 
     As used herein, the term “alloy” refers to a homogenous mixture or solid solution produced by combining two or more metallic elements, for example, to give greater strength or resistance to corrosion. For example, alloys include brass, bronze, steel, nitinol, chromium cobalt, MP35N, 35NLT, elgiloy, and the like. 
     As used herein, “nitinol” and “nickel titanium” are used interchangeably to refer to an alloy of nickel and titanium. 
     As used herein, “chromium cobalt” refers to an alloy of chromium and cobalt. 
     As used herein, “MP35N” refers to an alloy of nickel and cobalt. 
     As used herein, “35NLT” refers to a cobalt-based alloy that may also comprise chromium, nickel, molybdenum, carbon, manganese, silicon, phosphorum, sulphur, titanium, iron, and boron. 
     As used herein, “elgiloy” refers to an alloy of cobalt, chromium, nickel, iron, molybdenum, and manganese. 
     As used herein, a “body lumen” refers to the inside space of a tubular structure in the body, such as an artery, intestine, vein, gastrointestinal tract, bronchi, renal tubules, and urinary collecting ducts. In some instances, a body lumen refers to the aorta. 
     II. Embolic Protection Devices 
     Although certain embodiments and examples are described below, those of skill in the art will appreciate that the disclosure extends beyond the specifically disclosed embodiments and/or uses and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the disclosure herein disclosed should not be limited by any particular embodiments described below. 
       FIGS. 1A and 1B  illustrate embodiments of an embolic protection device  100 . The device  100  comprises a catheter  102  (e.g., a pigtail catheter) having a proximal end  114 , a distal end  116 , and a lumen  118  extending from the proximal end  114  to the distal end  116 . The lumen  118  may be configured to house a guidewire  540  ( FIGS. 5A and 5B ). The catheter  102  includes a distal portion  104  configured to assume a generally arcuate shape being at least a semi-circle. A side wall of the catheter  102  may optionally include one or more apertures  108  in the distal portion  104  that are configured to deliver one or more fluids (e.g., an imaging dye, oxygenated blood, saline, any combination thereof, or the like) to a body lumen  580  (see  FIG. 5 ). The apertures  108  (the plural intended to include embodiments in which the distal portion includes one aperture  108 ) are in fluid communication with the lumen  118 . The distal portion  104  of the catheter  102  includes a longitudinally-extending radiopaque marker  106  that is configured to be arcuate when the distal portion  104  is in the generally arcuate shape. The device  100  further comprises a multi-lobed self-expanding embolic filter  110  and a deployment device  112  (e.g., a longitudinally retractable outer sheath or a longitudinally retractable ring). The embolic filter  110  is disposed around the catheter  102 . As shown in  FIG. 1B , in its expanded configuration, the embolic filter  110  includes a distal opening  140  that is defined by the frame, faces the distal end  116  of the catheter, and extends proximally from the distal opening  140  to a closed proximal end  142 . The multi-lobed embolic filter  110  allows the distal opening  140  of the embolic filter  110  to engage at least a portion of the interior body lumen  580  (see  FIG. 5 ) wall. 
       FIG. 1C  is a cross-sectional view of the distal opening  140  of the embolic filter  110  when the embolic filter assumes an expanded configuration. The embolic filter  110  has at least two lobes  122 , which are disposed around the catheter  102  in a generally conical shape from the distal opening  140  to the closed proximal end  142  when the embolic filter  110  is in its expanded configuration. The lobes are defined by a frame  124  and include a filter medium  126  that is supported by and attached to at least a portion of the frame  124 . The embolic filter  110  is coupled (e.g., by adhering, welding, soldering, coupling using a separate component, combinations thereof, and the like) to the catheter  102 , so that the lobes  122  of the embolic filter  110  are disposed around the catheter. In some embodiments, the distal opening  140  of the embolic filter  110  has a diameter of from about 2 cm to about 6 cm (e.g., from about 2.5 cm to about 5 cm or about 4.5 cm). The embolic filter  110  can comprise any suitable size or diameter to accommodate anatomic variability in patients&#39; body lumens  580  (see  FIG. 5 ). In some embodiments, the embolic filter  110  is coupled to the catheter  102  along the entire length of the embolic filter  110 . In some embodiments, the embolic filter  110  is coupled to the catheter  102  at the proximal and/or distal ends of the embolic filter  110  and/or at any other points there between. 
       FIG. 1D  illustrates only the frame  124  of the embolic filter  110 . In some embodiments, the frame  124  comprises a shape memory material (e.g., a metal alloy or polymer). Examples of shape memory materials include, without limitation, nitinol, chromium cobalt, and/or other metal alloys such as MP35N, 35NLT, elgiloy, and the like. In some embodiments, the frame  124  is laser cut from a tube or a sheet. In some embodiments, the frame  124  may be configured so that it forms a generally arcuate shape. 
     In some embodiments, the filter medium  126  comprises a braided mesh, for example braided nitinol mesh. In some embodiments, the filter medium  126  comprises a porous membrane, for example a semi-permeable polyurethane membrane. In other embodiments, the filter has a pore size of from about 100 microns to about 150 microns (e.g., about 125 microns). 
     In some embodiments, the embolic filter  110  comprises an anti-thrombogenic coating (e.g., a heparin coating or other coating comprising a thrombin or platelet inhibitor) to advantageously reduce thrombogenicity. 
     The embolic filter  110  is configured to self-expand to a radially expanded configuration, shown in  FIGS. 1B and 1C , when not confined by the deployment device (e.g., outer sheath  112 ). 
     In some embodiments wherein the deployment mechanism comprises the outer sheath  112 , the outer sheath  112  is configured to be circumferentially disposed around at least a portion of the catheter  102  and the embolic filter  110 . The outer sheath  112  is configured to contain or house the embolic filter  110  in a collapsed configuration. The outer sheath  112  is longitudinally movable with respect to the catheter  102 , and can be longitudinally retracted, i.e., moved longitudinally in a proximal direction, to deploy the embolic filter  110  and longitudinally advanced, i.e., moved longitudinally in a distal direction, to recapture the embolic filter  110  and any embolic material collected by the embolic filter  110 . The embolic filter  110  is configured to self-expand upon longitudinal retraction of the outer sheath. A device according to the disclosure herein can comprise some or all of the features of the embolic protection device  100  shown in  FIGS. 1A-1B , and is described herein in various combinations and subcombinations. In some embodiments, the embolic filter  110  is configured to at least partially collapse upon longitudinal extension of the outer sheath. In these embodiments, the distal opening  140  assumes a substantially closed configuration thereby sequestering or substantially sequestering the filtered material. 
     The catheter  102  may comprise a flexible material so as to be maneuverable within a body lumen  580  (see  FIG. 5 ) as described herein. For example, in some embodiments, the catheter  102  comprises a metal or metal alloy. In other embodiments, the catheter  102  comprises a polymer (e.g., polyurethane, silicone, latex, polytetrafluoroethylene (PTFE), a plastic material, any combination thereof, or the like). In some embodiments, the catheter  102  comprises a metal-reinforced plastic (e.g., including nitinol, stainless steel, and the like). Other materials are also possible. In some embodiments, the catheter  102  is substantially free of latex (natural or synthetic), which may cause allergic reactions in some patients. In some embodiments, the catheter  102  comprises braid-reinforced tubing to advantageously increase the strength of the catheter  102 . In some embodiments, the catheter  102  comprises a braided catheter shaft including a layer of braided wire between two layers of catheter tubing, which may increase the strength of the catheter  102 . In some embodiments, the catheter  102  does not include a braided layer, which may increase the flexibility of the catheter  102 . In some embodiments, the catheter  102  comprises a lubricious coating, for example a coating having a low friction coefficient, to advantageously allow for smoother navigation through tortuous vasculature. In some embodiments, the catheter  102  coating has anti-thrombotic properties to advantageously inhibit thrombus formation. In some embodiments, the catheter  102  has a size (i.e., outside diameter) between about 3 French and about 5 French (between about 2 mm and about 3 mm). Other sizes are also possible, for example depending on the size of the target body lumen  580  (see  FIG. 5 ) of a particular patient. In some embodiments, the catheter  102  has a length between about 65 centimeters (cm) and about 135 cm. Other lengths are also possible, for example to allow for insertion of the catheter  102  in the femoral, radial, brachial, or subclavian artery. The catheter  102  can be manufactured, for example, by extrusion, injection molding, or another suitable process. 
     The radiopaque marker  106  extends longitudinally along a section of the distal portion  104  of the catheter  102 . When the distal portion  104  assumes the generally arcuate shape, the radiopaque marker  106  is also generally arcuate. In some embodiments, the radiopaque marker is located on a distal-most section of the catheter  102 . In some embodiments, the radiopaque marker  106  has a length of about 1 cm. The radiopaque marker  106  comprises a radiopaque material, for example platinum, tantalum, tungsten, palladium, and/or iridium. Other radiopaque materials are also possible. In some embodiments, a material may be considered radiopaque, for example, if the average atomic number is greater than  24  or if the density is greater than about 9.9 g/cm 3 . 
     The outer sheath  112  comprises a hollow tube configured to circumferentially surround at least a portion of the catheter  102 . The outer sheath  112  is longitudinally movable with respect to the catheter  102  and is configured to at least partially contain or house the embolic filter  110  in a collapsed configuration when circumferentially surrounding the embolic filter  110 , for example, as shown in  FIG. 1A . The outer sheath  112  is longitudinally proximally retractable to release the embolic filter  110  to the expanded, open configuration when not contained by the outer sheath  112 . In some embodiments, the outer sheath  112  extends proximally to the proximal end  114  of the catheter  102  so that the user can grasp and manipulate the outer sheath  112  directly. In some embodiments, the outer sheath  112  extends proximally over only a portion of the catheter  102 , and a secondary device (e.g., a push-rod such as found in stent deployment systems) is coupled to the outer sheath  112  (e.g., to the proximal end of the outer sheath  112 ) to allow for indirect manipulation of the outer sheath  112 . Manipulation of the outer sheath  112  may be mechanical, electronic, manual, combinations thereof, and the like. 
       FIGS. 2A and 2B  illustrate embodiments of an alternative deployment mechanism for an embolic protection device  200  comprising a catheter  202 , an embolic filter  210 , and a movable outer sheath  212 . In some embodiments, the outer sheath  212  can include an optional lip  232  protruding inwardly from the distal end of the outer sheath  212 . The catheter  202  can include one or more shoulders  234  (e.g., a distal shoulder  234   a  and a proximal shoulder  234   b ) protruding outwardly from an outer wall of the catheter  202 . The lip  232  of the outer sheath  212  is configured to engage the shoulder or shoulders  234  of the catheter  202  to inhibit or prevent the outer sheath  212  from moving excessively in either the proximal or distal direction. The lip  232  and shoulder  234  may be arcuate, pronged, and combinations thereof, and the like. 
     In some embodiments, the outer sheath  212  and/or the catheter  202  comprise nubs and/or detents configured to provide information to the user about the longitudinal position of the outer sheath without inhibiting further movement. In some embodiments, the outer sheath  212  and the catheter  202  comprise lips  232 , shoulders  234 , and detents and nubs (e.g., to inhibit longitudinal movement of the outer sheath  212  excessively in either direction, and to provide information about the extent of movement of the outer sheath  212  relative to the catheter  202  (e.g., ½ retracted, ¼ retracted, etc.)). 
     Benefits of the outer sheath  212  deployment mechanism may include its simplicity, ease of operation, and small number of moving parts. The embolic protection device  200  is well-suited for use in conjunction with delicate cardiac procedures having serious risks. As the duration of the procedure increases, the risk of complications typically increases as well. Therefore, it can be advantageous that the user be able to quickly and easily deploy and recapture the embolic filter  210 . A more complicated device could be more difficult to operate and could be more likely to malfunction or cause adverse effects. The ability to move the outer sheath  212  relative to the filter  210  can advantageously allow the user to partially recapture the embolic filter  210 , for example to adjust the width of the distal opening  140 . In some embodiments, narrowing the distal opening  140  allows the user to introduce a second catheter or instrument to the patient&#39;s body lumen  580  (see  FIG. 5 ) and maneuver the second catheter or instrument around and past the catheter  202  and embolic filter  210 , as described herein. 
       FIGS. 3A-4D  illustrate embodiments of an embolic protection device  300  in which an embolic filter  310  is movably coupled to a catheter  302  and is longitudinally movable with respect to the catheter  302 . In some embodiments, the embolic filter  310  is coupled to an intermediate tube  330  that at least partially circumferentially surrounds the catheter  302 . The intermediate tube  330  is longitudinally movable with respect to the catheter  302 . An outer sheath  312  is configured to at least partially circumferentially surround both the catheter  302  and the intermediate tube  330 . The intermediate tube  330  and the outer sheath  312  can be moved simultaneously and independently. The longitudinal position of the embolic filter  310  with respect to the catheter  302  can be adjusted while the embolic filter  310  is in the collapsed configuration or in a deployed or partially deployed, expanded configuration. In some embodiments, the perimeter of the distal opening of the embolic filter  310  comprises one or more radiopaque markers to allow the user to visualize the position of the distal opening, for example, with respect to various anatomical landmarks. For example, if the user is performing a procedure on a patient&#39;s aortic valve and wants to prevent emboli from entering the cerebral arteries, the radiopaque markers can be used to ensure the distal opening of the embolic filter  310  is positioned in the ascending aorta upstream from the carotid arteries. 
       FIG. 3A  shows the embolic filter  310  confined in a closed configuration by the outer sheath  312  and a distal end of intermediate tube  330  at position a. If the intermediate tube  330  is held stationary at position a, the outer sheath  312  can be retracted to deploy the embolic filter  310 , as shown in  FIG. 3C . If the intermediate tube  330  and outer sheath  312  are instead moved simultaneously, the embolic filter  310  remains confined by the outer sheath  312  while the longitudinal position of the embolic filter  310  is adjusted. For example,  FIG. 3B  shows the embolic filter  310  still confined by outer sheath  312 , but the intermediate tube  330  has been retracted so that the distal end of the intermediate tube  330  is at position b. If the intermediate tube  330  is then held stationary at position b, the outer sheath  312  can be retracted to deploy the embolic filter  310 , as shown in  FIG. 3D . The intermediate tube  330  and outer sheath  312  can be moved to adjust the longitudinal position of the embolic filter  310  in a deployed or partially deployed configuration. For example, the intermediate tube  330  and outer sheath  312  can be moved simultaneously to retract the intermediate tube  330  from the position as shown in  FIG. 3C  to the position b as shown in  FIG. 3D . When the embolic filter  310  is partially deployed, the embolic filter  310  may not be in contact with the vessel walls and freely movable, for example due to lack of wall apposition. When the embolic filter  310  is fully deployed, any debris dislodged during movement may be trapped in the embolic filter  310 . 
     In addition to those described in detail herein, a wide variety of deployment mechanisms for embolic filters are possible. For example, a deployment system may comprise a portion of an annular sheath including inward end protrusions that are guided in tracks along the catheter body. Certain such embodiments may advantageously reduce the profile of the catheter. For another example, a deployment system may comprise a threaded sheath that longitudinally moves upon twisting by the user. For yet another example, a deployment system may comprise a plurality of annular bands that can capture the embolic filter longitudinally and/or circumferentially. Combinations of the deployment systems described herein and other deployment systems are also possible. 
       FIG. 4  shows another example embodiment of an embolic protection device  400  comprising a catheter  402 , a deflector  460 , an embolic filter  410 , and a movable outer sheath  412 . In some embodiments, the device  400  is similar to embolic protection device  100  with the addition of the deflector  460 . 
     Various types and designs of deflectors can be used with an embolic protection device such as device  400 . Such deflectors can have different shapes and/or sizes and can vary in where and how they are coupled to the catheter. For example, deflectors can be made in various sizes, for example to accommodate differences in patient anatomy. In some embodiments, the deflector comprises a shape memory material, for example including nitinol, chromium cobalt, and/or alloys such as MP35N, 35NLT, elgiloy, and the like. In some embodiments, the deflector comprises a porous membrane, for example a semi-permeable polyurethane membrane, mounted to a self-expanding frame, for example a frame comprising a shape memory material. 
     The example deflector  460  shown in  FIGS. 4A-4C  has a generally butterfly or elliptical shape with two wings or petals  460   a  and  460   b  extending to either side of a central axis  464 . The wings  460   a  and  460   b  may be the same or different in size shape, material, and the like. The deflector  460  is coupled to a side of the catheter  402  via an elongate member  462  that is coupled (e.g., by adhering, welding, soldering, coupling using a separate component, combinations thereof, and the like) at one end to the central axis  464  of the deflector  460  and at the other end to the catheter  402 . In some embodiments, the elongate member  462  comprises a shape memory material, for example including nitinol, chromium cobalt, and/or alloys such as MP35N, 35NLT, elgiloy, and the like that is configured (e.g., shape set) to bias the deflector away from the catheter  402 . The deflector  460  is configured to release to an open configuration, shown in  FIG. 4B and 4C , when not confined by, for example, an outer sheath  412 . In some embodiments, the deflector  460  is configured to fold along the central axis  464  away from the elongate member  462  so that the wings or petals  460   a  and  460   b  come together and the deflector  460  can be contained in, for example, an outer sheath  412 , as shown in  FIG. 4A . As shown in  FIG. 4A , the deflector  460  can initially be folded and contained in the outer sheath  412  such that the wings or petals  460   a  and  460   b  are positioned distal to the central axis  464 . In some embodiments, the deflector  460  can initially be folded in the opposite direction such that the wings or petals  460   a  and  460   b  are positioned proximal to the central axis  464 . 
     In some embodiments, the catheter  402  is a pigtail-type catheter as shown in  FIG. 4  and described herein. In some embodiments, the deflector  460  and embolic filter  410  can be coupled to another type of catheter, for example a catheter without a distal portion configured to assume an arcuate shape. The embolic filter  410  can be similar to the embolic filters  110  and  210  shown in  FIGS. 1A-1D and 2A-2B  and described herein. In some embodiments, the embolic filter  410  is coupled to the catheter  402  proximal to the deflector  460 , for example as shown in  FIG. 4A-4B . In some embodiments, the embolic filter  410  is coupled to the catheter  402  distal to the deflector  460 . The embolic filter  410  is coupled so that it is disposed around the catheter  402 . This configuration advantageously allows the embolic filter  410  to engage the interior body lumen  580  (see  FIG. 5 ) wall, as the position of the catheter  402  within the body lumen  580  (see  FIG. 5 ) may be affected by the deployed deflector  460 . 
     The combination of the deflector  460  and the embolic filter  410  can advantageously provide additional protection against potential complications resulting from thrombi in the blood stream. For example, if the embolic filter  410  (e.g., the distal end of the embolic filter  410 ) is distal to the deflector  460 , the embolic filter  410  can serve as the primary means of embolic protection and the deflector  460  can serve as the secondary means of embolic protection. If some blood is able to flow around the filter  410  rather than through it, the deflector  460  serves as a back-up protection device and prevents any debris not captured by the filter  410  from entering the cerebral arteries and traveling to the brain. If the embolic filter  410  is proximal to the deflector  460 , the deflector  460  can serve as the primary means of embolic protection and the embolic filter  410  can serve as the secondary means of embolic protection. The deflector  460  first deflects debris away from the carotid arteries, then the embolic filter  410  captures debris (e.g., including deflected debris) as blood flows through the descending aorta. 
     In some embodiments, the catheter  402  and outer sheath  412  can have lips, shoulders, nubs, and/or detents, for example similar to those shown in  FIGS. 2A-2B  and described herein. For example, lips, shoulders, nubs, and/or detents can be positioned on the catheter  402  distal to the deflector  460 , between the deflector  460  and embolic filter  410 , and proximal to the embolic filter  410  to engage corresponding lips, shoulders, nubs, and/or detents on the outer sheath  412 . The lips, shoulders, nubs, and/or detents can advantageously provide the user with information about the longitudinal position of the outer sheath  412  so that the user knows when neither, one, or both of the deflector  460  and embolic filter  410  are deployed. In some embodiments, either or both of the deflector  460  and embolic filter  410  can be movably coupled to the catheter  402  via an intermediate tube similar to that shown in  FIGS. 3A-3D  and described herein. 
     III. Methods of Capturing Embolic Debris 
       FIGS. 5A-5D  show one embodiment of a method of capturing embolic debris during a closed-heart medical procedure, for example an aortic valve replacement procedure. The method can be performed using, for example, an embolic protection device  100 ,  200 ,  300 , or  400  as described herein. 
     In one embodiment, a guidewire  540  is percutaneously inserted into a body lumen  580  of a patient, for example a femoral, radial, brachial, or subclavian artery, and navigated to the desired anatomical location, for example, the level of the ascending aorta. The guidewire  540  can be a J tipped wire having a diameter of about 0.035 in. (approx. 0.089 cm). Other types and dimensions of guidewires  540  are also possible. 
     In some embodiments, the proximal end of the guidewire  540  is inserted into the opening at the distal end  116  of the catheter  102 . When the guidewire  540  is in the lumen  118  of the catheter  102  at the distal portion  104  of the catheter  102 , the distal portion  104  of the catheter is straightened or assumes the curvature of the guidewire  540 . The distal end  116  of the catheter  102  is inserted into the body lumen  580  by tracking the lumen  118  of the catheter  102  over the guidewire  540 , as shown in  FIG. 5A . The outer diameter of the guidewire  540  is smaller than the inner diameter of the embolic protection device  100  such that the embolic protection device  100  may be tracked over the guidewire  540 . The inner surface of the lumen  118  and/or the outer surface of the guidewire  540  may include a lubricious coating to reduce friction during tracking. The guidewire  540  keeps the distal portion  104  of the catheter  102  substantially straight (e.g., from being in the generally arcuate state) as the catheter  102  is inserted into and navigated within the patient&#39;s body. 
     The radiopaque marker  106  is used to visualize and position the distal portion  104  of the catheter  102  during tracking. The guidewire  540  is retracted, i.e., moved longitudinally in a proximal direction, a sufficient distance to allow the distal portion  104  of the catheter  102  to assume the generally arcuate shape, as shown in  FIG. 5B . The distal portion  104  of the catheter  102  is positioned at the desired anatomical landmark, for example, the lower border of the noncoronary cusp of the aortic valve. The radiopaque marker  106  is on the distal-most section of the distal portion  104 . 
     In some embodiments of the method, the proximal end  114  of the catheter  102  is connected to a contrast material injector, and contrast material is injected into the lumen  118  of the catheter  102 , for example to visualize the anatomy around the device  100 . The contrast material exits the catheter  102  lumen  118  through the opening at the distal end  116  of the catheter  102  and/or through one or more apertures  108  in the side wall of the catheter  102 . Injecting contrast material can aid in visualizing and positioning the catheter  102 . 
     In some embodiments, a second guidewire is percutaneously inserted into a second body lumen, for example the other femoral artery, and a second catheter is tracked over the second guidewire. The second catheter can carry a medical device or instrument, for example, a replacement valve, a valve repair system, or a radio frequency ablation system. Once the second catheter and associated device or instrument are properly positioned, the outer sheath  112  of the catheter  102  is longitudinally proximally retracted, allowing the embolic filter  110  to assume the expanded, deployed configuration, as shown in  FIG. 5C . The second guidewire and/or the second catheter can also be positioned after the embolic filter  110  is released. The open distal end  140  of the embolic filter  110  is located in the ascending aorta so that blood flows through the filter before flowing into the carotid arteries or descending aorta. In some embodiments, when the embolic filter  110  is deployed, the catheter  102  rests against the interior lumen wall, thereby stabilizing the catheter  102 . The procedure can then be performed, and embolic debris dislodged or otherwise in the blood stream during the procedure is captured by the embolic filter  110 . 
     After the procedure, the outer sheath  112  is longitudinally distally advanced to recapture the embolic filter  110 , returning the embolic filter  110  to the collapsed configuration and capturing any embolic debris  550  contained within the embolic filter  110 , as shown in  FIG. 5D . The second catheter and catheter  102  can then be withdrawn from the patient&#39;s body. The catheter  102  can be retracted over the guidewire  540  or without straightening the distal portion  104  of the catheter  102  because the arcuate shape of the distal portion  104  is atraumatic to the blood vessels. 
       FIG. 6  illustrates another embodiment of a method of deflecting and capturing embolic debris during a medical procedure using an embolic protection device. The embolic protection device is similar to the embolic protection device  200  that is described in  FIG. 2A-2D , wherein an intermediate tube  230  is longitudinally movable with respect to the catheter  202 . Some embodiments employ a separate deflector device  562  of  FIG. 5A-5B . 
       FIG. 7  illustrates another embodiment of deflecting and capturing embolic debris. An embolic protection device  700  of  FIG. 7  comprises a catheter  702  (e.g., a pigtail catheter) with a radiopaque marker  706  and an embolic filter  710  disposed around the catheter  702  similar to embolic filter  410  illustrated in  FIGS. 4A-4B  and described herein. As shown, a deflector  760  is mounted to a shaft  762  and contained in an introducer  768  during insertion. The introducer  768  is introduced into the patient&#39;s body through the artery (e.g., right radial artery) and navigated to the aortic arch via the brachiocephalic artery. Once in position, the deflector  760  is deployed from the introducer and pulled back to cover the brachiocephalic and left common carotid artery. In some patients, the deflector  760  might also cover the left subclavian artery. In some embodiments, the deflector  760  can be introduced and deployed before the catheter  702  is navigated to the aortic arch. During a subsequent medical procedure, the deflector  760  can prevent emboli from entering the carotid arteries, and the embolic filter  710  can capture emboli deflected by the deflector  760  before it travels to other parts of the patient&#39;s body. The method can also be performed with various other embolic protection devices, for example as described herein, and deflector devices that may vary in configuration and how they are introduced into the body and navigated to the aortic arch. 
     In some embodiments, the procedure performed is a cardiac valve replacement procedure, for example an aortic valve replacement procedure. The embolic protection device  100  is introduced into the patient and navigated to the aortic valve as described herein and shown in  FIGS. 5A-5D . The radiopaque marker  106  assists in delineating the lower border of the noncoronary cusp to assist in proper positioning of a percutaneously implanted replacement aortic valve. Once the catheter  102  is positioned, a second guidewire can be percutaneously inserted into a second body lumen and navigated to the level of the ascending aorta or left ventricle. A balloon can be tracked over the second guidewire to the aortic valve. The outer sheath  112  is then retracted to deploy the embolic filter  110 . Balloon inflation of the valve can then be performed, and the embolic filter  110  captures embolic debris  550  dislodged during the procedure or otherwise in the blood stream. After balloon pre-dilation, the outer sheath  112  is advanced to recapture the embolic filter  110  and any embolic debris  550  contained within the embolic filter  110 . The balloon is removed, and a second catheter carrying a valvular prosthesis is advanced to the level of the ascending aorta by tracking the catheter over the second guidewire. The outer sheath  112  is again retracted to redeploy the embolic filter  110 . The radiopaque marker  106  allows the user to properly position the valve prosthesis, for example about 4 mm to about 6 mm below the lower border of the noncoronary cusp. After the procedure is completed, the outer sheath  112  is advanced to recapture the embolic filter  110  and any captured embolic debris  550 , and the catheters are removed from the body. In some embodiments, the second catheter can be removed prior to advancing the outer sheath  112  to recapture the embolic filter  110  and embolic debris  550 . 
     In some embodiments, the procedure is a cardiac valve repair procedure. The method described herein can also be adapted for a mitral valve repair or replacement procedure. In some embodiments, the procedure is a radio frequency ablation procedure, for example to treat atrial fibrillation. In some embodiments, the procedure is a catheterization procedure or structural heart procedure. 
     Other Embodiments 
     It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims.