Sheaths, delivery systems, and methods for transcatheter device implantation - Patents.com

Abstract

An arterial access sheath for performing a procedure, such as a transcatheter aortic valve procedure, having a marker configured to indicate an orientation of a distal end region of the sheath. Related systems, devices, and methods are provided.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority under 35 U.S.C. §119(e) to Provisional Application No. 63 / 248,091, filed September 24, 2021. The disclosure of the provisional application is incorporated by reference in its entirety. [Background technology]

[0002] The present disclosure relates to devices and methods for precisely deploying devices, such as prosthetic heart valves, in a desired orientation relative to an anatomical structure.

[0003] Patients with defective aortic valves are often candidates for heart valve replacement surgery. The traditional treatment involves surgery to replace the heart valve with a prosthetic valve. The procedure involves a gross thoracotomy or median sternotomy, cardiopulmonary bypass and cardioplegia, surgical access and removal of the diseased heart valve, and replacement of the heart valve with a prosthetic mechanical or tissue valve. Valves implanted in this manner have a durability of 10 to 15 years for tissue valves and even longer for mechanical valves, and have historically provided good long-term outcomes for these patients. However, heart valve replacement surgery is highly invasive, requires long recovery times, and is associated with short- and long-term complications. For patients who are at high surgical risk or who are inoperable, this procedure may not be an option.

[0004] Recently, a minimally invasive approach to heart valve replacement has been developed. Known as transcatheter aortic valve implantation (TAVI) or replacement (TAVR), this approach relies on the development of a foldable prosthetic valve mounted on a catheter-based delivery system. This type of prosthetic valve can be inserted into the patient through a relatively small incision or vascular access site and implanted into a beating heart without cardiac arrest. The advantages of this method are less surgical trauma, faster recovery, and lower complication rates. For patients who are at high surgical risk or who are inoperable, this method is a good alternative to traditional surgery. Examples of this technology include the SAPIEN transcatheter valve (Edwards Lifesciences, Irvine, CA) and the CoreValve system (Medtronic, Minneapolis, MN). Examples of this technology are described in U.S. Pat. No. 6,454,799, which is incorporated herein by reference in its entirety.

[0005] There are two main routes for valves inserted via the TAVI approach. The first is a percutaneous or surgical femoral artery cut-down and vascular approach (called the transfemoral approach) via the femoral artery. Once in position in the femoral artery, the valve mounted on the delivery system is advanced retrogradely (against the direction of blood flow) up the descending aorta, around the aortic arch, and across the ascending aorta to be positioned opposite the native aortic valve. Transfemoral aortic valve delivery systems are typically 90 cm or longer in length and require the ability to navigate around the aortic arch. The relatively small diameter of the femoral artery and the frequent presence of arteriosclerotic disease in the iliofemoral anatomy limit the maximum diameter of the delivery system to approximately 24 French (0.312 inches). The second route is called the transapical approach, where the left ventricle is accessed through a mini-thoracotomy at the apex and the valve delivery system is advanced antegradely (in the same direction as blood flow) to the location of the aortic valve. This route is much shorter and more direct than the transfemoral route, but involves surgical puncture followed by closure of the heart wall.

[0006] Other approaches have been reported, including access via the subclavian artery and direct puncture of the ascending aorta through a small thoracotomy. The subclavian approach is used when the transfemoral route is contraindicated, but it may block flow to the cerebral vessels through the ipsilateral common carotid artery. Direct aortic puncture is usually considered when anatomical problems, including vascular disease, require the exclusion of all other routes. Perforation of the aortic wall and subsequent closure are associated with surgical risks, including aortic dissection or rupture.

[0007] The transfemoral approach to the aortic valve is generally well known in the medical community, as opposed to the transscapular and other alternative approaches. Accessing the ascending aorta through the femoral artery is a standard procedure for interventional cardiologists. Balloon valvuloplasty via the transfemoral approach has been performed for many years. Surgical approaches such as transscapular access or direct aortic puncture are less familiar and require a physician with both surgical and endovascular skills. The surgical approach techniques are still evolving, and it is yet to be determined whether they offer advantages over the transfemoral or transclavicular approaches. However, the transfemoral or transclavicular approaches also have their problems. First, the vessels to be accessed are often too small and / or affected by atherosclerosis to use the artery as an access point. The second problem is that the path from the access point to the aortic valve usually involves at least one large turn of at least 90° and a relatively narrow radius of curvature of less than half an inch, requiring some flexibility in the delivery system. This need for flexibility limits the design parameters of both the valve and the delivery system, and along with the required length of the delivery system, reduces the level of control in precisely positioning the valve.

[0008] TAVR also requires precise placement of the new valve over either the diseased native valve or the previously implanted valve. Longitudinal and circumferential alignment of the prosthetic valve to the native anatomy is crucial for the success of the procedure. In particular, it must be correctly positioned to avoid obstructing coronary blood flow. Clinically, the alignment of the implanted valve pillars and leaflets to the native or implanted aortic valve commissures is called commissure alignment. Long intravascular tracking lengths, especially in the transfemoral approach, significant curvature of the tracking path, and the risk of vessel blockage due to injury or release of embolic particles during tracking are special challenges for current TAVR implantation or delivery systems, limiting their ability to precisely place the valve.

[0009] The transfemoral approach is limited by the long endovascular tracking length and the large curvature of the iliac and aortic arches. There is a high risk of vessel blockage, including vessel injury and / or dislodging of embolic particles during tracking. These limitations impact the ability of the TAVR system to perform accurate placement.

[0010] A typical TAVR procedure involves creating multiple access sites. The TAVR device typically requires a large-bore femoral access sheath, while diagnostic catheters are inserted through a small-bore femoral access. Small-bore femoral venous access is used for insertion of electrophysiologic pacing leads. Small-bore radial artery access may be used for delivery of embolic protection devices. The use of multiple access sites during the procedure limits the success of the TAVR procedure and involves additional patient risks, for example, the need to close multiple access sites and an increased risk of the device inadvertently contacting or migrating with other devices, such as a TAVR delivery system delivered in the femoral artery contacting an embolic protection device delivered in the radial artery. Summary of the Invention

[0011] In one aspect, an arterial access sheath for performing transcatheter aortic valve therapy is disposed comprising an elongate body having at least one lumen extending from a proximal opening to a distal opening, a proximal hub coupled to the proximal opening of the elongate body and configured to remain external to the patient, the proximal hub comprising one or more proximal markings, and a radiopaque marker band embedded within a distal end region of the elongate body, the radiopaque marker band comprising spaced apart notches around a circumference of the distal end region circumferentially corresponding to the one or more proximal markings. The notches form radiopaque gaps in the marker band to form at least two radiopaque distal markings. An overlap of the at least two distal markings indicates a circumferential direction of the distal end region of the elongate body.

[0012] The elongate body may have a length adapted to be introduced into an access site at the left or right common carotid artery, or the left or right subclavian artery. The shape of the distal markings may form a second, different shape when the at least two distal markings at least partially overlap one another. The shape may be a rectangle, a circle, a triangle, a diamond, an arrow, a hemisphere, or a square. The at least two distal markings may include at least two groups of distal markings. The at least two groups may be distinguishable from one another. The at least two groups may be distinguishable by the shape of the markers. The at least two groups may be distinguishable by the number of markers. The radiopaque marker band may include a polymer filled with one or more radiopaque materials. The radiopaque materials may be tungsten, tantalum, barium sulfate, platinum, stainless steel, and gold. The distal markings may further include a button of radiopaque material protruding away from a sidewall of the distal end region of the elongate body. The proximal marking may be on a proximally facing surface of the hub and may be directly visible to a user. The proximal marking may include an adhesive marking, a painted marking, a molded marking, an etched marking, an embossed marking, or a printed marking on the proximal hub. The elongate body may have an asymmetry about its circumference, and the proximal marking corresponds to the asymmetry. The elongate body may be non-circular in cross-section.

[0013] In a related aspect, a method of treating an aortic valve is provided that includes forming a penetration in a wall of a common carotid artery through the patient's neck and introducing an arterial access sheath through the penetration. The access sheath includes an elongate body coupled to a proximal hub configured to remain external to the patient and including one or more proximal markings. A distal end region of the elongate body includes a radiopaque marker band having spaced apart notches about a circumference of the distal end region to circumferentially correspond to the one or more proximal markings. The notches form radiopaque voids in the marker band to form at least two radiopaque distal markings. The method further includes aligning a distal end region of the elongate body relative to the target anatomical structure under fluoroscopic guidance in response to the overlapping circumferential positions of the at least two distal markings, introducing the prosthetic valve through the access sheath using one or more proximal markings corresponding to the at least two distal markings as a guide, and deploying the prosthetic valve at or near the location of the native aortic valve.

[0014] In a related aspect, an arterial access sheath for delivering transcatheter aortic valve therapy is provided. The sheath includes an elongate body having multiple lumens extending parallel to one another between corresponding proximal and distal openings, the distal openings being located at a distal-most end of the elongate body. The sheath includes an embolism protection device lumen extending between the proximal openings and an exit port, the exit port being disposed through a sidewall of the elongate body and a proximal distance from the distal-most end of the elongate body, a first radiopaque marker band embedded within a distal end region of the elongate body, and a second radiopaque marker band embedded within a region of the elongate body near the exit port. The sheath includes a proximal hub configured to remain outside the patient, the proximal hub coupled to the corresponding proximal openings of the elongate body and the proximal opening of the embolism protection device lumen.

[0015] The multiple lumens may include an interventional device lumen having an inner diameter between 12 French and 24 French, or between 4 mm and 8 mm. The multiple lumens may include at least two auxiliary lumens having an inner diameter between 3 French and 9 French, or between 1 mm and 3 mm. The sheath may further include an irrigation valve configured to simultaneously irrigate the multiple lumens and disposed on the proximal hub. The distance the exit port is spaced proximal to the distal-most end of the elongate body may be at least about 10 mm to about 30 mm. The elongate body may have a length adapted to be introduced into an access site in the left or right common carotid artery, or the left or right subclavian artery, such that the distal-most end is positionable within the descending aorta. The length may be between about 10 cm to about 50 cm. The proximal hub may include one or more proximal directional markings that are directly visible to a user. The proximal directional markings may be on a proximally facing surface of the hub. At least one of the first radiopaque marker band and the second radiopaque marker band may include notches spaced apart about a circumference of the distal end region to circumferentially correspond to the one or more proximal markings. The notches may form radiopaque gaps in the marker band to form the at least two radiopaque distal markings. An overlap of the at least two distal markings may indicate a circumferential direction of the distal end region of the elongate body.

[0016] In a related aspect, a method of treating a blood vessel with an arterial access sheath including an elongate body having multiple lumens and a proximal hub is provided. The method includes inserting the elongate body through a penetration in a wall of a patient's blood vessel such that the proximal hub is accessible from outside the patient, inserting a first device through a first proximal opening, through the proximal hub, into a first lumen of the multiple lumens and removing it through a distal opening from the first lumen, and inserting a second device through a second proximal opening, through the proximal hub, into a second lumen of the multiple lumens and removing it through an exit port from the second lumen. The first and second lumens have different inner diameters. The distal opening from the first lumen is located at a distal-most end of the elongate body, and the exit port from the second lumen is located through a sidewall of the elongate body a proximal distance from the distal-most end.

[0017] The elongate body may include at least a first radiopaque marker band embedded within a distal end region of the elongate body near the distal opening and a second radiopaque marker band embedded within a region of the elongate body near the exit port. The region of the elongate body having the second radiopaque marker may be located adjacent a proximal side of the exit port, adjacent a distal side of the exit port, or may be located along a circumference incorporating the exit port. The first device may include an intravascular valve delivery system and the second device may include an embolic protection device. The proximal hub may include a plurality of proximal markers providing information regarding the plurality of lumens. The information may include at least one of a size of the lumen, a location of the distal opening, and a use of the lumen.

[0018] In some variations, one or more of the following may be selectively included in any feasible combination in the above methods, apparatus, devices, and systems, as described in detail in the accompanying drawings and the following description. Other features and advantages will be apparent from the description and drawings.

[0019] These and other aspects are described in detail below with reference to the following drawings: Generally speaking, the figures are illustrative and are not to scale, either absolutely or relatively, and are intended for illustrative purposes. The relative placement of features and elements has been altered for clarity of illustration. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 shows a side view of one embodiment of an access sheath. [Figure 2A] FIG. 2A shows the distal end region of the access sheath of FIG. [Figure 2B] 2B is a proximal end view of the access sheath of FIG. 1. FIG. [Figure 3A] FIG. 3A is a proximal end view of an access sheath having a series of proximal directional markings. [Figure 3B] FIG. 3B illustrates the distal end region of the access sheath of FIG. 3A at different stages of rotation, showing the placement of markings on the radiopaque marker band. [Figure 3C] FIG. 3C illustrates the distal end region of the access sheath of FIG. 3A at different stages of rotation, showing the placement of markings on the radiopaque marker band. [Figure 3D] FIG. 3D illustrates the distal end region of the access sheath of FIG. 3A at different stages of rotation, showing the placement of markings on the radiopaque marker band. [Figure 4A] FIG. 4A shows the distal end region of the access sheath at different stages of rotation showing alternative placement of markings on the radiopaque marker band. [Figure 4B] FIG. 4B shows the distal end region of the access sheath at different stages of rotation showing alternative placement of markings on the radiopaque marker band. [Figure 4C] FIG. 4C shows the distal end region of the access sheath at different stages of rotation, illustrating alternative placement of markings on the radiopaque marker band. [Figure 5A]FIG. 5A shows the distal end region of the access sheath at different stages of rotation showing alternative placement of markings on the radiopaque marker band. [Figure 5B] FIG. 5B shows the distal end region of the access sheath at different stages of rotation showing alternative placement of markings on the radiopaque marker band. [Figure 5C] FIG. 5C shows the distal end region of the access sheath at different stages of rotation showing alternative placement of markings on the radiopaque marker band. [Figure 6A] 6A-6D are cross-sectional views of elongate bodies of sheaths having various non-circular shapes. [Figure 6B] 6A-6B are cross-sectional views of elongate bodies of sheaths having various non-circular shapes. [Figure 6C] 6A-6C are cross-sectional views of elongate bodies of sheaths having various non-circular shapes. [Figure 7A] FIG. 7A illustrates an embodiment of a transcarotid aortic valve prosthesis and delivery system. [Figure 7B] FIG. 7B illustrates another embodiment of a transcarotid aortic valve prosthesis and delivery system. [Figure 7C] FIG. 7C shows circumferential alignment of an access sheath having distal markings and a valve delivery system having distal markings. [Figure 8A] 8A-8D show various stages of circumferential alignment of the access sheath of FIG. 5A relative to the tricuspid of the aortic valve. [Figure 8B] 8B illustrates various stages of circumferential alignment of the access sheath of FIG. 5A relative to the tricuspid of the aortic valve. [Figure 8C] 8C illustrates various stages of circumferential alignment of the access sheath of FIG. 5A relative to the tricuspid of the aortic valve. [Figure 8D] 8D illustrates various stages of circumferential alignment of the access sheath of FIG. 5A relative to the tricuspid of the aortic valve. [Figure 9A] FIG. 9A is a side view of the access sheath. [Figure 9B]FIG. 9B shows a proximal end view of the access sheath of FIG. 9A. [Figure 9C] FIG. 9C shows a perspective view of the proximal end region of the access sheath of FIG. 9A. [Figure 10A] FIG. 10A shows a perspective view of the distal end region of the access sheath of FIG. 9A. [Figure 10B] FIG. 10B shows a distal end view of the access sheath of FIG. 9A. [Figure 10C] FIG. 10C shows the access sheath of FIG. 9A inserted via the left common carotid artery with the distal end region in the aorta and the lateral exit directed toward the right carotid artery. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The systems described herein allow arterial access, such as transcarotid access via the common carotid artery, or subclavian access via the subclavian artery, or transfemoral access via the femoral artery, to the native aortic valve for implantation of a device, such as a prosthetic aortic valve, into the heart or aorta. The systems maximize the physician's efficiency, control, and deployment precision of transcatheter aortic valve replacement (TAVR) of a diseased valve, for example, by providing circumferential, axial, and / or radial alignment of the system relative to the anatomy and / or lumens specific to the various components being deployed.

[0022] As used herein, "circumferential" alignment or positioning generally refers to alignment or positioning about the longitudinal axis of the system. For example, the access sheath 110 may have a longitudinal axis that extends through the lumen between a proximal opening to the lumen and a distal opening from the lumen. Circumferential alignment of the distal end region of the access sheath 110 refers to the relative rotation of the distal end region of the access sheath 110 about the longitudinal axis in the circumferential direction of the tube. Circumferential alignment may be used interchangeably with rotational alignment, for example. As used herein, "axial" alignment or positioning generally refers to alignment or positioning along the longitudinal axis of the system. Axial alignment of the distal end region of the access sheath 110 refers to the relative extension of the sheath 110 through the vessel or along or in the longitudinal axis of the system. A longitudinally adjusted access sheath 110 is moved axially along the longitudinal axis, generally further distal or proximal to the anatomy into which the access sheath 110 is inserted. Axial alignment may be used interchangeably with longitudinal alignment. As used herein, "radial" alignment or position refers to an alignment or position at an angle to the longitudinal axis of the system. The radial alignment of the distal end region of the access sheath 110 refers to the inclination of the distal end region relative to the longitudinal axis and from a particular perspective.

[0023] Although there are particular diagrams showing the sheath being inserted via a particular access site (e.g., the common carotid artery), a similar sheath or sheath / shunt system may be designed for subclavian or transfemoral access. Although the sheath 110 is described in the context of delivery of a heart valve, the description of the orientation between the access sheath 110 and tools inserted through the lumen 120 of the sheath 110 is useful for other types of treatments, including treatment of coronary arteries, renal arteries, hepatic arteries, thoracic aortic aneurysms, abdominal aortic aneurysms, etc.

[0024] Transfemoral, transcarotid, or subclavian access to the aortic valve can be achieved by percutaneous puncture or direct cut of the artery. Cut may be advantageous because percutaneous vascular occlusion is difficult, especially in larger arteriotomies such as the common carotid artery. If necessary, a prestitch can be placed at the arteriotomy site to facilitate occlusion at the end of the procedure. An access sheath with accompanying dilator and guidewire is provided sized to fit the access artery. For carotid access, the access sheath is inserted into the artery down toward the aortic arch. For example, either the left or right common carotid or subclavian artery may be selected as the access site based on factors including disease state of the proximal artery and / or aorta, and the angle of entry of the carotid or sternal artery into the aorta. The carotid artery may become occluded distal to the access site. When accessed by direct surgical cut and arteriotomy, occlusion may be achieved using a vascular clamp, vascular loop, or Rummel tourniquet. Alternatively, the access sheath itself may include an occlusion element, such as an occlusion balloon, adapted to occlude the artery to prevent embolic particles from entering the carotid artery distal to the access site during the procedure.

[0025] 1 illustrates a side view of an embodiment of an arterial access sheath 110 formed from an elongate body 115 having a lumen 120. Although the sheath 110 is shown as having a single lumen 120, the sheath 110 can incorporate multiple lumens, as described below with respect to Figures 9A-9C and 10A-10C, which are discussed in more detail below. While the sheath 110 is described as having a single lumen, the same features may be incorporated into a sheath 110 having multiple lumens 120.

[0026] The elongate body 115 may be a thin-walled polymeric tube having an atraumatic distal tip 122 and a proximal hub 124 to allow for hemostasis and insertion of instruments. The distal end region of the elongate body 115 may incorporate a radiopaque marker band 123 having a number of orientation markings 125 to indicate circumferential alignment of the distal end region of the sheath 110 under fluoroscopy. The proximal end region of the sheath 110, such as the proximal hub 124, which is intended to remain external to the patient during use, may further incorporate one or more orientation markings 127. The proximal orientation markings 127 may be circumferentially adjusted or aligned with the distal orientation markings 125 in a manner that provides detectable guidance to the user regarding the circumferential and longitudinal alignment of the distal end region of the sheath 110. The directional markings 125, 127 on the sheath 110 can be circumferentially aligned or aligned with an interventional instrument or delivery system used with the sheath 110, such as an implantable heart valve and delivery system, such that the circumferential position of the instrument is more easily and clearly understood during use.

[0027] FIG. 2A shows a detailed perspective view of the distal end region of the access sheath 110 including a radiopaque marker band 123 having multiple directional markings 125. The markings 125 may be arranged around the circumference of the wall of the elongate body 115 in multiple groups that may be distinct from one another such that the markings 125 provide information regarding the circumferential direction of the distal end region. FIG. 2B shows a proximal end view of the proximal end hub 124 of the access sheath 110 and multiple directional markings 127. Similar to the distal markings 125, the proximal markings 127 may be arranged on the circumference of the tool, for example, on the proximally facing surface of the hub 124. The proximal markings 127 may be arranged in multiple groups that coordinate with the distal markings 125 at the distal end region of the sheath 110 to provide information regarding the circumferential direction of the distal end region of the sheath 110. Thus, if the distal end region includes a first group of markings 125 that includes a single identifiable shape, such as a single circle (or a square, rectangle, triangle, diamond, arrow, hemisphere, or other shape), so will the first group of markings 127 on the proximal hub 124. Whatever arrangement of markings is provided on the distal end region of the sheath, the markings 127 on the proximal hub 124 will be similar. As an example, FIGS. 2A-2B show a first group of distal markings 125a and a first group of proximal markings 127a that can include a single identifiable shape or number of markings (e.g., a single circle, square, rectangle, triangle, diamond, arrow, hemisphere, or other shape) and can be positioned at distinct locations around the circumference of the wall of the elongate body. A second group of distal markings 125b and a second group of proximal markings 127b can include two identifiable shapes or markings (e.g., two circles, squares, rectangles, triangles, diamonds, arrows, hemispheres, or other shapes) spaced apart around the circumference. The third group of markings 125c and the third proximal group of markings 127c can include three distinct shapes or markings (e.g., three circles) spaced a further distance apart around the circumference, and the fourth group of markings 125d and the fourth proximal group of markings 127d can include another number of distinct shapes or markings (e.g., four circles) spaced a further distance apart around the circumference.

[0028] Various markings or groups of markings 125, 127 around the circumference are contemplated, so long as the markings or groups of markings 125, 127 are distinguishable from one another. Similarly, various shapes or numbers of shapes within a particular group of markings 125 are contemplated, including circles, squares, rectangles, triangles, diamonds, arrows, hemispheres, or other shapes. For example, FIG. 3A shows another series of distinguishable markings 127 on the proximal hub 124, with each "group" being a single marker having a particular distinguishable shape. The "front" of the sheath 110 can be identified by a first shape marker 127a (e.g., diamond), and the "side" of the sheath 110 relative to the first marker 127a can be identified by a second shape marker 127b, 127c. The distal markings 125 do not have to exactly match the shape, size, or number of the proximal markings 127. For example, FIGS. 3B-3D show the distal end region of the sheath of FIG. 3A at different stages of rotation. Despite having three proximal markings 127, only two markings 125a, 125b are shown spaced apart from each other around the circumference of the radiopaque marker band 123. The first marking 125a can be an arrow or other type of asymmetric shape that is different from the shape of the second marking 125b. FIG. 3B shows the first and second markings 125a, 125b aligned so that they do not overlap, and FIG. 3C shows the first and second markings 125a, 125b partially aligned and partially overlapping. FIG. 3D shows the first and second markings 125a, 125b perfectly aligned with each other such that the rectangular arrow shapes completely overlap and form a symmetrical X-shape. The alignment of the asymmetric markings 125a, 125b when fully overlapping and aligned provides the user with an additional message of where the "front" of the catheter is in space around the longitudinal axis. One of the markings 127a on the proximal hub 124 may indicate this desired side. Knowing which particular side or "front" of the catheter is is important to the user when deploying asymmetric tools or devices through the catheter, as described in more detail below.

[0029] As used herein, "fully overlapping" refers to a circumferential rotation of the distal end region of the access sheath 110 about the catheter's longitudinal axis and a radial angle of the catheter relative to the longitudinal axis where the pair of markings 125 are substantially aligned with one another for a selected field of view under fluoroscopy. For example, if the pair of markings 125a, 125b are formed as rectangular openings or notches in the radiopaque band 123, when the markings 125a, 125b are fully overlapping, all four sides of the rectangle of one marking 125a are substantially aligned with all four sides of the rectangle of the other marking 125b, so that only a single rectangular shape is visible under fluoroscopy (e.g., as a lack or gap of radiopacity in the radiopaque distal end region) when viewed in a conventional tricuspid view or right / left cusp overlap view. Angiographic projections are often perpendicular to an imaginary plane of the aortic annulus. In the traditional tricuspid view, all three cusps are visible and generally correspond to the left anterior oblique cranial (LAO-CRA) view. In the right / left cusp superposition view, the right coronary cusp (RCC) and the left coronary cusp (LCC) are superimposed on top of each other using multislice CT (MSCT) or angiography, generally corresponding to the right anterior oblique caudal (RAO-CAU) view, while the non-coronary cusp (NCC) remains separated. This forms the bicuspid view, the cusp superposition view. The cusp superposition view is advantageous in that it allows the assessment of the deployment depth at the NCC level, as well as the wire position and tension. In addition, the right / left cusp superposition view allows the surgeon to clearly predict the spatial orientation of the native valve commissures, since one of these three commissures is located between the right and left coronary cusps. The superposition of non-radiopaque markings allows the sheath to be precisely aligned to the native commissures. The access sheath 110 and delivery system appear substantially vertical in this view.

[0030] 4A-4C show alternative arrangements of markings 125 on a radiopaque marker band 123 that provide the user with information regarding circumferential positioning due to their overlapping arrangement. The marker band 123 can include a pair of markings 125a, 125b spaced apart from one another around the circumference of the band 123. The marker band 123 can further incorporate a marking 125c that is different from the other two markings to identify the "front" of the access sheath 110. The third marking 125c is a small protrusion or button of radiopaque material that protrudes from the side wall of the sheath and is visible under fluoroscopy. FIG. 4A shows the first and second markings 125a, 125b not aligned with one another, while FIG. 4B shows the first and second markings 125a, 125b partially aligned and partially overlapping. 4C shows the first and second markings 125a, 125b perfectly aligned with one another such that they no longer appear as two markings but as a single marking indicating complete circumferential alignment. The third marking 124c is located at the "front" of the catheter and is visible.

[0031] 5A-5C show alternative arrangements of markings 125 on a radiopaque marker band 123 that provide the user with information regarding circumferential position through an overlapping arrangement. The marker band 123 can include a first pair of markings 125a, 125b that are similar in shape and size to each other but spaced around the circumference of the catheter. The marker band 123 can include a second pair of markings 125c, 125d that are similar in shape and / or size to each other but spaced around the circumference of the catheter. However, the second pair of markings 125c, 125d can differ in shape and / or size from the first pair of markings 125a, 125b such that the "front" of the catheter is identified when the pair of markings are aligned. FIG. 5A shows all of the markings not aligned with each other. FIG. 5B shows the markings partially aligned and partially overlapping. 5C shows a first pair of markings 125a, 125b aligned with one another and a second pair of markings 125c, 125d aligned with one another. A fifth marking 125e may be different from the other two pairs of markings to identify the "forward" side of the access sheath, as described above.

[0032] Regardless of placement or configuration, distal directional markings 125 and proximal directional markings 127 coordinate in a manner that is apparent to the user, as they provide information regarding the circumferential alignment of the distal end region of access sheath 110 under fluoroscopic guidance and are guided by proximal directional markings 127 that are visible at or near the hub of sheath 110. This coordination is useful when delivering an interventional device through the sheath if the device has a "handedness" or some asymmetry that involves implantation and / or delivery according to a particular direction.

[0033] The sheath 110 can be used to deploy any of a variety of devices that require precise positioning within the vasculature according to the appropriate circumferential orientation, including prosthetic valves, heterogeneous porous stents with asymmetric braids or coils that create areas of low or high blood flow, palisade or branched devices, flow diverters configured to divert blood flow away from an aneurysm, fistula, or ruptured vessel and have areas that allow flow to healthy tissue, vascular occlusion devices incorporating asymmetric braids or differential lattice density, and the like.

[0034] The radiopaque marker bands 123 may be formed from the catheter's polymer filled with one or more radiopaque materials including tungsten, tantalum or barium sulfate, platinum, stainless steel, or gold. The distal orientation markings 125 may be formed as notches in the radiopaque marker bands 123 forming gaps in these radiopaque materials, detectable under fluoroscopy as having a unique contrast to the bands 123. Having the markings 125 formed as gaps in the radiopaque material has two important advantages. First, the relatively large radiopaque marker bands 123 are easily visible (location and distal end) under angiography, which is important for safely tracking the device through the vessel. Second, laser cutting or machining the notches into the radiopaque material allows for precise spatial orientation between the markings during device manufacturing (as opposed to depositing multiple orientation markers / components in a controlled pattern onto a polymer shaft). The marking 125 may be formed in the band 123 as a cutout that forms one or more gaps in the radiolucency of the band 123 that appear as an elongated slot, notch, hatch mark, hole, channel, or other area in the polymeric material of the sheath 110 that is devoid of radiopaque material. Thus, unlike the remainder of the radiopaque band 123, the marking 125 appears under fluoroscopy as a distinct area of ​​light within an otherwise dark band, since the marking 125 is entirely polymeric with no radiopaque material. In some embodiments, the marking or pair of markings 125 is formed as a radiotransparent slot having an elongated rectangular shape in the radiopaque band 123. In other embodiments, the marking or pair of markings 125 is formed as a radiotransparent opening having a circular shape in the radiopaque band 123. In yet another embodiment, a marking or pair of markings 125 are formed in band 123 as radiolucent cutouts having different shapes (up and down arrows) that, when overlapping, appear to form a new marking having a different distinct shape (X-shape).The distinct area formed by the marking 125 may have any of a variety of shapes, including geometric and freeform. Alternatively or additionally, the distal marking 125 may be a material that is different from the material of the marker band 123, such that it appears as a unique mark with a unique contrast under fluoroscopy relative to the band 123. The different material may also be radiopaque, but may be lighter than the remainder of the band 123, such that the marking does not appear as dark as the remainder of the band 123. Thus, the marking 125 may have a radiopacity that is different from the radiopacity of the band 123, the difference being discernable under fluoroscopy.

[0035] The proximal markings 127 are located on an area of ​​the sheath 110 that is external to the patient and are visible to the naked eye during a procedure and do not need to be radiopaque. The proximal markings 127 may be applied according to any of a variety of known methods, including adhesive markings, painted markings, molded markings, etched markings, embossed markings, printed markings, or otherwise applied to an area of ​​the sheath 110 that is external to the patient, such as the proximal hub 124, for easy viewing by a user during a procedure.

[0036] The elongate body 115 of the sheath 110 may be circular in cross section or may be non-circular in cross section. A non-circular cross section of the elongate body 115 of the sheath 110 allows the sheath to be keyed to another component. The keyed fit can be coordinated with circumferential alignment of the distal and proximal markers 125, 127. FIGS. 6A-6C show various non-circular cross sections of the elongate body 115 of the sheath 110. In some embodiments, the inner and outer dimensions of the sheath 110 are non-circular, while in other embodiments, only the inner or outer dimensions of the sheath 110 are non-circular. In other words, the outer diameter of the sheath 110 may be circular while the inner diameter of the sheath 110 is non-circular, or vice versa. The cross section, whether the entire cross section of the sheath 110 or only the cross section of the lumen 120, may include a flattened polygonal shape or a freeform shape with only a specific orientation. The cross-sectional shape may be oval, D-shaped, triangular, rectangular, or other non-circular. The sheath 110 may additionally or alternatively incorporate a rail shape (see FIG. 6A). An elongate body 115 that includes an asymmetry about its circumference may incorporate proximal markings that correspond to the asymmetry.

[0037] The keyed cross-section of the access sheath may be designed to receive a similarly keyed cross-section of an endovascular delivery system such that the cross-section is circumferentially aligned to the deployed implantable device. For example, a TAVR delivery system deployed through lumen 120 may have outer dimensions that correspond in shape or key to the cross-sectional shape of lumen 120 to circumferentially align to an implantable heart valve (see FIGS. 7A-7B). The delivery system may be inserted such that the valve is aligned against proximal markings 127 on the access sheath 110 and the corresponding shapes of the inner diameter of the sheath 110 and the outer diameter of the delivery system match to achieve the desired orientation at the distal end region of the sheath 110.

[0038] The markers 125, 127 and the non-circular cross-section of the sheath body 115 can provide reproducible positioning that provides accurate and proper orientation of the delivered valve.

[0039] In some embodiments, the hub 124 incorporates an overall shape, such as a non-circular or polygonal shape, or incorporates a described shape, such as a bump-out or rail along a particular direction that can be visually and / or physically aligned with the distal orientation marking 125 on the distal end region of the access sheath 110. Thus, the hub 124 need not incorporate a proximal orientation marking 127 itself, but rather can be shaped to provide the same type of information as the proximal orientation marking 127 provides. Such a shaped hub 124 can also provide keyed alignment with one or more devices inserted through the hub 124 such that the circumferential orientation of the device is known and predictable.

[0040] The hub 124 may incorporate a silicone slit valve or luer attachment for connection in a Tuohy-Borst manner. The hub 124 of the arterial access sheath 110 may include a Y-arm for aspiration, for delivery of contrast or saline irrigation, and / or may be fluidly connected to a shunt 112, which provides a shunt lumen or pathway for blood to flow from the arterial access sheath 110 to a return site, such as a venous return site or collection reservoir. At this point, a retrograde or reverse flow condition may be established in at least a portion of the artery. The Y-arm is for inflation of an occlusion balloon in the distal end region of the sheath via the inflation lumen (if present), and the hemostatic valve is for introduction of an intravascular valve delivery system into the sheath.

[0041] The sheath 110 may have a working length (i.e., the portion of the sheath that is insertable into the artery during use) that varies to accommodate a wide range of devices having different sizes. The working length may be between about 10 cm and 50 cm. In embodiments in which the sheath 110 contains a single lumen 120, the lumen of the sheath may have an inner diameter large enough to accommodate insertion of an intravascular valve delivery system, such as an 18 French to 22 French (0.236 inch to 0.288 inch) system. In other embodiments in which the sheath 110 contains multiple lumens, the lumen size may vary as described in more detail below. The sheath size may be as small as 4 French to 24 French. In some embodiments, the delivery system has an inner diameter as small as about 0.182 inch.

[0042] In an embodiment, the access system may include one or more embolic protection elements to provide embolic protection for one or both carotid arteries. For example, the access system may include a filter to provide embolic protection for one or both carotid arteries. In a variation of this embodiment, the filter is deployed via the contralateral carotid artery, brachial artery, or subclavian artery and placed in the aortic arch across the arterial ostium. If the sheath access site is the left common carotid artery, the filter may be placed across the arterial ostium of the sternal artery (also known as the brachiocephalic artery). If the sheath access site is the right common carotid artery, the filter may be placed across the arterial ostium of the left common carotid artery. In a variation of this embodiment, the filter is deployed across both the sternal artery and the left common carotid artery, or across all three head and neck vessels (sternal artery, left common carotid artery, left subclavian artery). The filter element may be built into the access sheath 110. Alternatively, the filter element may be a separate element that fits into the access sheath 110. For example, the filter element may be a coaxial element slidably connected to the access sheath or an element disposed side-by-side with the access sheath. The filter element may have a stretchable frame such that it can be inserted into the artery in a collapsed state, but then expands at the target site to place the filter element across the opening of the artery or arteries. The embolic protection provided by the sheath may include any of the systems described in U.S. Pat. Nos. 8,545,552 and 1,092,5709, or WO 2021 / 087480, each of which is incorporated herein by reference.

[0043] An endovascular valve delivery system, including a prosthetic valve and a delivery catheter, may be advanced through the access sheath 110. The delivery system may be torsionally controllable and incorporate similar distal and proximal markings as described above with respect to the access sheath. The various configurations of distal and proximal markings described above with respect to the access sheath 110 are also contemplated herein with respect to the endovascular valve delivery system. The coordinated distal and proximal markings of the delivery system provide the user with information regarding the circumferential orientation of the implantable device relative to the delivery system and relative to the access sheath through which the device is delivered. This allows the user to circumferentially position the sheath at a desired location within the patient using fluoroscopic guidance, insert the endovascular valve delivery system along a guided path, and deliver the implantable device at a known circumferential location.

[0044] An exemplary valve and delivery system configured to be delivered through an access sheath 110 as described herein is shown in FIG. 7A. FIG. 7A shows an embodiment of a balloon expandable prosthetic aortic valve 205 mounted on the distal end of an endovascular valve delivery system 200. The delivery system may have a distal tapered tip 220 at the distal end region of an inner shaft 210 and an expandable balloon 215. In one embodiment, the system also has an outer sleeve, such as a pusher sleeve 230, that is slidable along the long axis of the device and maintains the position of the valve on the balloon during delivery. The proximal control assembly includes a mechanism for retracting the pusher sleeve 230, such as a slide button 270 on the proximal handle 240. In FIG. 7A, the pusher sleeve 230 is shown retracted from the valve 205 and the proximal balloon 215 so that the valve 205 can be expanded without interference from the pusher sleeve 230. A connector 250 allows an inflation device to be connected to the balloon inflation lumen of the balloon 215. The proximal rotating hemostatic valve 260 provides a seal around a guidewire (not shown) as the valve delivery system 200 is advanced over the guidewire and into position, as well as allowing for flushing of the system.

[0045] The delivery catheter may have a length of 30 cm, 40 cm, 60 cm, 70 cm, 80 cm, up to about 110 cm. In one embodiment, the delivery catheter has a working length designed for transcarotid access and has a working length of about 30 cm to about 50 cm. In one embodiment, the delivery catheter has a working length designed for transfemoral access and is about 110 cm. The route from the transcarotid access site is much shorter and straighter than the transfemoral or subclavian approaches. As a result, a delivery system for deployment through an access sheath placed in the carotid artery can be shorter and have a much stiffer proximal portion, both of which allow for greater push and torque control, resulting in improved control of the positioning and deployment of the prosthetic valve. The distal portion can have increased flexibility, allowing for precise tracking around the ascending aorta and into position at the aortic annulus. The materials of the delivery system may include reinforced, higher durometer, and / or thicker wall materials compared to current delivery systems to provide this increased stiffness.

[0046] In one embodiment, the working length of the valve delivery system 200 is configured to enable delivery of the valve to the aortic annulus from a transcarotid access site. Specifically, the working length of the valve delivery system 200 is between 45 cm and 60 cm. The delivery system shaft can also be configured for delivery from a right carotid or left carotid access site. Specifically, the shaft has a stiff proximal portion 280 and a more flexible distal portion 290. In one embodiment, the distal portion 290 is two to four times more flexible than the stiff proximal portion 280. In one embodiment, the flexible distal portion 290 is between one-quarter and one-third of the total working length of the valve delivery system 200. Specifically, the flexible distal portion 290 can range from 10 cm to 20 cm. In an alternative embodiment, the valve delivery system 200 has one or more flexible length transitions between the flexibility of the flexible distal portion 290 and the flexibility of the stiff proximal portion 280.

[0047] Another embodiment of a valve and delivery system 300 configured for transcarotid delivery is shown in FIG. 7B. A self-expanding prosthetic aortic valve 305 is attached to the distal end of the endovascular valve delivery system 300. The delivery system has a distal tapered tip 320 at the distal end of an inner shaft 310. The valve 305 is disposed on the inner shaft 310 and is housed in a retractable sleeve 330 that is slidable along the longitudinal axis of the device. The proximal control assembly includes a mechanism for retracting the retractable sleeve 330, such as a slide button 370. In one embodiment, the valve 305 and sleeve 330 are designed such that the sleeve 330 can be advanced distally again to abut the valve 305 and collapse the valve 305 so that the valve 305 can be repositioned if the first position is incorrect. A proximal rotating hemostatic valve 360 ​​seals around the guidewire (not shown) as the valve delivery system is advanced over the guidewire to reach a home position, as well as to flush the system.

[0048] As with the previous embodiment, the working length of the valve delivery system 300 is configured to enable delivery of the valve 305 from a transcarotid access site to the aortic annulus. Specifically, the working length of the valve delivery system 300 is between 45 cm and 60 cm. The delivery system shaft is also configured for delivery from a right or left carotid access site. Specifically, the shaft has a stiff proximal portion 380 and a more flexible distal portion 390. In one embodiment, the distal portion is two to four times more flexible than the stiff proximal portion. In one embodiment, the flexible distal portion is between one-quarter and one-third of the total working length of the valve delivery system. Specifically, the flexible distal portion ranges from 10 cm to 20 cm. In an alternative embodiment, the valve delivery system has one or more flexible length transitions between the flexibility of the flexible distal portion and the flexibility of the flexible proximal portion.

[0049] TAVR requires precise placement of the valve on either a diseased native valve or a previously implanted valve. Longitudinal and circumferential alignment of the new valve is critical for the procedure to be successful. Alignment is crucial to ensure correct placement without obstructing blood flow to the coronary arteries. Clinically, circumferential alignment of the valve pillars and leaflets relative to the native or implanted aortic valve commissures is also necessary for the procedure to be successful. The directional markings 125, 127, and / or key placement of the proximal hub, and / or the described features of the sheath provide guidance regarding proper alignment of the sheath relative to the anatomy. The delivery system 200 (or 300) can incorporate one or more distal directional markings 225 as well as one or more corresponding proximal directional markings that provide visual guidance regarding the orientation of the valve 205 (or valve 305) positioned relative to the delivery system 200. The distal and proximal directional markings can have the same nature and function as the directional markings 125, 127 described above with respect to the access sheath 110. FIG. 7C illustrates an embodiment of an access sheath 110 having an embolic protection filter 211 disposed at its distal end region and a valve delivery system 200 extending through the access sheath 110. The distal end region of the access sheath 110 is shown having aligned distal markings 125a / 125b forming an X-shape and a third distal marking 125c protruding from a side of the distal end region of the sheath 110. The delivery system 200 is shown having a valve 205 attached to the distal end region and advanced over a guidewire 119. The distal end region of the delivery system 200 can include corresponding distal directional markings 225a / 225b forming an X-shape and a third distal marking 225c protruding from the same side of the distal end region of the delivery system 200 as the side from which the third distal marking 125c protrudes from the sheath 110, indicating proper alignment about the longitudinal axis for deployment within the target anatomy.

[0050] 8A-8D show various stages of circumferential alignment of the access sheath 110 with respect to the three cusp line 805 of the aortic valve, including the non-coronary cusp (NCC), the right coronary cusp (RC), and the left coronary cusp (LC), as viewed under fluoroscopy representative of a right / left cusp superposition view. FIG. 8A shows the distal end of the sheath 110 positioned within the ascending aorta AA. The distal orientation markings 125 of the radiopaque band 123 are not aligned. The configuration of the distal orientation markings 125 is similar to that shown in FIGS. 5A-5C, with two alignment slits, two forward circles, and a fifth marking indicating "forward." FIG. 8B shows the access sheath 110 rotated about the longitudinal axis of the elongated body, with the distal orientation markings 125 partially aligned. FIG. 8C shows the access sheath 110 further rotated about the longitudinal axis of the elongate body such that the distal markings 125 are perfectly aligned with each other. FIG. 8D shows the delivery of the valve through the aligned access sheath 110. The distal markings 125 of the access sheath can indicate a particular direction to the patient. The two markings 125 can overlap to form one mark at the distal end of the sheath 110 such that upon insertion of the implantable device, the device is properly oriented with respect to the target site (the aortic valve in the case of FIG. 8D) since the other marking 125 faces a particular part of the patient (e.g., faces anteriorly to the patient). The implantable device can be inserted through the sheath such that the commissures of the implant are aligned with the proximal markings 127 that align with the distal markings identified under fluoroscopy. Distal directional markings 125 may be properly oriented relative to the anatomy under fluoroscopy, and proximal orientation markings 127, visible outside the patient and in direct coordination with distal directional markings 125, may be used to guide proper insertion of the implantable delivery system into hub 124 of sheath 110. The implantable delivery system may further incorporate one or more features to ensure proper alignment during insertion of the system.

[0051] The features of the access sheaths and delivery systems described herein are useful not only for TAVR, but also for a variety of other interventional methodologies where precision of implantation and direction of device deployment is desired, for example, in the treatment of coronary, renal, hepatic arteries, thoracic, and abdominal aortic aneurysms. Although the methods described herein are described in the context of TAVR, it should be understood that the sheaths described herein can be used in any of a variety of methods.

[0052] In one embodiment, the access sheath 110 is first inserted into the vasculature either via a percutaneous puncture or via direct surgical cut-down and puncture of the carotid artery. The access sheath 110 can be introduced through a penetration with the tip pointing straight down towards the arterial ostium. The transcarotid approach to the aortic valve may be achieved via an LCCA or via an RCCA.

[0053] The distal end region of the access sheath 110 can be aligned in a right / left leaflet superimposition view (see FIG. 8A). The sheath 110 can be rotated about its longitudinal axis while viewing under fluoroscopy until the distal orientation markings 125 indicate the appropriate orientation relative to the anatomy. For example, at least some of the distal orientation markings 125 can be overlapping and another distal orientation marking 125 can indicate a particular orientation or anatomy of the patient (see FIGS. 8B-8C).

[0054] Once the access sheath is positioned and optional embolic protection means are deployed via occlusion, aspiration, and / or filter elements, access to the aortic valve is gained via a guidewire 119 (e.g., a 0.035 inch or 0.038 inch guidewire) that is inserted into the sheath 110 and directed down the ascending aorta and across the native aortic valve. Prior to valve implantation, a pre-dilatation of the native aortic valve can be performed using an appropriately sized dilation balloon, e.g., a valvuloplasty balloon. The guidewire 119 is used to position the balloon across the valve, which is inflated, deflated, and removed while the guidewire is in place.

[0055] The endovascular prosthetic valve 205 and delivery system 200 are then inserted over the guidewire 119 through the access sheath 110. The valve 205 and delivery system 200 can be introduced with the commissures facing the proximal marking 127 of the sheath 110, which directly corresponds to the distal marking 125 of the sheath 110. The valve 205 positioned on the delivery system 200 can be threaded through the access sheath 110 to the site of the native aortic valve. The prosthetic valve 205 can be adjusted longitudinally along its long axis and / or circumferentially about its long axis, as needed, until a desired alignment is achieved. The prosthetic valve 205 is then deployed at or near the location of the native aortic valve (see FIG. 8D). A carotid approach can provide improved circumferential control of the sheath 110 and prosthetic device, improving the accuracy of alignment.

[0056] At the end of the implantation step, the function of the implanted prosthetic valve 205 can be assessed by ultrasound, contrast injection under fluoroscopy, or other imaging modalities. Depending on the design of the delivery system 200, the prosthetic valve 205 may be adjusted as necessary to achieve optimal valve function and position before final deployment. The delivery system 200 and guidewire 119 are then removed from the access sheath 110. After removal of the delivery system 200 and guidewire 119, the embolic protection element is removed. Suction may be continued during this time to capture embolic debris trapped in the sheath tip, occlusion element, and / or filter element. Various forms of embolic protection devices can be deployed, including occlusion elements, filters, occlusion balloons, suction, etc.

[0057] The access sheath 110 is then removed and the access site is closed. If the access was a direct puncture of a surgical incision, the vessel is closed by tying pre-placed sutures, manually suturing, or using a surgical vascular closure device, as described in more detail below. If the access was percutaneous, percutaneous closure methods and devices may be employed to achieve hemostasis at the access site. In one embodiment, a closure device is applied to the site of the penetration prior to introducing the arterial access sheath through the penetration. There are various types of closure devices.

[0058] The access sites mentioned above are the left or right common carotid artery. Other access sites are possible, such as the left and right subclavian arteries or the left and right brachial arteries. Although these arteries may require a longer and / or more tortuous route to the aortic valve, they offer other advantages over carotid access, such as the ability to work away from the patient's head, avoidance of unfavorable neck anatomy, such as a history of carotid endarterectomy or other neck surgery or radiation, and less risk in the event of access site complications. Additionally, carotid disease or small carotid arteries may preclude common carotid access. At any of these access sites, occlusion, aspiration, and / or filtering of the head and neck vessels during TAVI can increase the speed and accuracy of the procedure and reduce the incidence of embolic complications.

[0059] The access sheath 110 may be first inserted into the vasculature via either percutaneous puncture or direct surgical cut-down and puncture of the femoral artery, into the descending aorta, across the arch, and into the ascending aorta. The access sheath 110 may be aligned under fluoroscopy as described above with the selected cusp superposition view (e.g., tricuspid, R / L). The TAVR device may be inserted into the sheath 110 with the irrigation port on the handle oriented according to convention, such as at 3 o'clock or 12 o'clock. The TAVR device may be advanced through the sheath 110 to the aortic valve. The handle of the TAVR delivery device may be torqued until proper circumferential alignment is achieved, although the TAVR device may be withdrawn into the descending aorta prior to deploying the valve.

[0060] Figure 9A is a side view of another embodiment of an arterial access sheath 110 having multiple lumens. The features of the access sheath 110 described above with respect to Figures 1-8D apply to the access sheath 110 shown in Figures 9A-9C through 10A-10C. For example, the access sheath 110 of Figures 9A-9C through 10A-10C may incorporate a number of directional markings as described above in detail above, which may or may not be repeated below with respect to Figures 9A-9C through 10A-10C, useful for identifying the proper orientation of the sheath 110 relative to the anatomy under fluoroscopy.

[0061] The elongate body 115 of the sheath of Figures 9A-9C may be a thin-walled polymeric tube having an atraumatic distal tip 122 and a proximal hub 124 to allow for hemostasis and device insertion through each of multiple lumens. In one embodiment, the elongate body 115 may include at least two lumens 120, 130. In another embodiment, the elongate body 115 may include at least three lumens 120, 130, 140. In yet another embodiment, the elongate body 115 may include four lumens 120, 130, 140, 150. The proximal hub 124 may incorporate hemostasis devices such as silicone slit valves or other types in each lumen.

[0062] The first lumen 120 may have an inner diameter sufficient to accommodate an interventional device, such as, for example, a TAVR device. The first lumen 120 may be the largest lumen, and may be between about 12 French (4 mm) and about 24 French (8 mm), or about 18 French (6 mm). The second and third lumens 130, 140 may be smaller than the first lumen 120, and may be, for example, between about 3 French (1 mm) and up to about 9 French (3 mm). The smaller second and third lumens 130, 140 may be used for delivery of diagnostic or pigtail catheters or other devices, contrast agents, therapeutic agents, aspiration, and / or pressure measurements.

[0063] In some embodiments, the sheath 110 can additionally include an additional lumen 150 designed to exit through a sidewall of the elongate body 115 rather than at the most distal end of the sheath 110. The lumen 150 can be substantially straight along at least a portion of its length, extending from a proximal opening 156 into the lumen 150 along the longitudinal axis, parallel to the lumen 120, toward the distal end region of the sheath 110. The lumen 150 can curve near the distal end region and exit the sidewall at an exit port 151. The exit port 151 of the lumen 150 can be located at least about 10 mm and up to about 30 mm away from the most distal end 122 of the sheath 110 to allow delivery into the aortic arch for entry into a target vessel (e.g., the contralateral carotid artery) for protection. The inner diameter of the lumen 150 can be smaller than the first lumen 120, for example about 5 French. Exit port 151 from lumen 150 may be used to facilitate delivery of an embolism protection device therethrough.

[0064] The embolic protection device used in combination with TAVR is typically advanced into the contralateral carotid, brachial, or subclavian artery and / or positioned in the aortic arch across an arterial ostium. For example, if the sheath access site is the left common carotid artery, the filter may be advanced through lumen 150 and exit from exit port 151 and positioned across the arterial ostium of the sternal artery (also known as the brachiocephalic artery). If the sheath access site is the right common carotid artery, the filter may be positioned across the arterial ostium of the left common carotid artery. In a variation of this embodiment, the filter is deployed across both the sternal and left common carotid arteries, or across all three head and neck vessels (sternal, left common carotid, and left subclavian). The filter element may include an expandable frame, such that the filter element may be inserted into lumen 150 in a collapsed state and then expanded at the target site to position the filter element across the opening of an artery or arteries.

[0065] The length and inner diameter of the lumen may be varied for appropriate device compatibility. The inner diameter of the first lumen 120 may be large enough to accommodate the insertion of an intravascular valve delivery system or other interventional system. As discussed above, the sheath 110 may have a working length (i.e., the portion of the sheath that is insertable into the artery during use) that varies to accommodate a wide range of devices having different sizes. The working length may be about 10 cm to 50 cm. The working length of the sheath 110 may vary depending on the access site. For a sheath adapted to be inserted into the common carotid artery for purposes of accessing the descending aorta, the length of the elongated sheath body 115 may range from 10 cm to about 50 cm, typically about 20 cm. For a sheath adapted to be inserted into the descending aorta via the femoral artery, the length of the elongated sheath body 115 may range from 30 to 100 cm, typically 80 cm. The sheath outer diameter may be of various lumen and wall thickness combinations, and may be approximately 24 French, with TAVR lumens at 18 French and auxiliary lumens at 3 to 6 French.

[0066] The distal end region of the elongate body 115 may incorporate one or more radiopaque marker bands 123 to indicate the location of the sheath under fluoroscopy. As discussed above, the radiopaque markers 123 may be formed from the catheter polymer filled with one or more radiopaque materials including tungsten, tantalum or barium sulfate, platinum, stainless steel, or gold. In an embodiment, the distal most tip of the elongate body 115 may include a first marker 123 and another region of the elongate body 115 may include a second marker 123 that differs in size, shape, and / or color from the first marker 123. For example, the first marker may include two radiopaque bands 123a, 123b spaced apart from one another near the distal end of the sheath 110 so as to be identifiable under fluoroscopy (see FIGS. 10A-10C). The second marker may include a single radiopaque band 123c spaced apart proximally from the first marker bands 123a, 123b. The single radiopaque band 123c may be positioned near the exit port 151 from the third lumen 150 to aid in locating the port in an appropriate location for deployment of a device through the lumen 150. The second marker 123b may be positioned just proximal to the exit port 151, just distal to the exit port 151, or along a circumference that encompasses the exit port 151. The markers 123a, 123b, 123c need not be in the form of solid bands that encircle the entire circumference of the sheath 110. In some embodiments, distal markers 123a, 123b may incorporate two radiopaque bands, while exit port marker 123c may be a distinct mark at the location of exit port 151, e.g., a mark that surrounds the port 151 itself as opposed to the entire circumference of the sheath 110 at that location.

[0067] The sheath 110 may incorporate a number of distal markings 125 to indicate circumferential alignment of the distal end region of the sheath 110 under fluoroscopic guidance, as described above with respect to Figures 1A-8D.

[0068] The proximal end region of the sheath 110, such as the proximal hub 124, that is intended to remain external to the patient during use, may additionally incorporate one or more visible markings 127 (see FIG. 9A). The proximal markings 127 are located on the region of the sheath 110 that is external to the patient and are visible to the naked eye during the procedure, and therefore do not need to be radiopaque. The proximal markings 127 may be applied according to any of a variety of known methods, including as an adhesive sticker, painted, molded, etched, embossed, or other methods, to the region of the sheath 110 that is external to the patient, such as the proximal hub 124, for easy viewing by the user during the procedure.

[0069] The proximal markings 127 can provide detectable guidance to the user regarding the different lumens, as well as the circumferential orientation of the distal end region, as described with respect to FIGS. 1A-8D. The proximal markings 127 can provide information regarding the size of the lumen, the location of the distal opening, and / or the intended purpose of the lumen (e.g., TAVR vs. embolic protection device) using different symbols, colors, and / or text. As an example, a lumen 150 having an exit port 151 positioned through a sidewall can be identified by a marking 127 indicating the side of the sheath 110 on which the exit port 151 is located, such as with an arrow pointing to the side positioned next to the proximal opening 156 to that lumen 150. This can help the user, for example, rotate the access sheath 110 to ensure that the exit port 151 is properly positioned within the aortic arch so that an embolic protection filter inserted through the lumen 150 is deployed from a region of the catheter facing caudally or near a branch vessel away from the arch. FIG. 10C shows an access sheath inserted via the left common carotid artery LCCA with a distal end in the aortic arch between the descending aorta (DAo) and the ascending aorta (AAo). A lateral exit is directed to the right common carotid artery (RCCA). As another example, at least a region of the lumen, including the proximal opening to the lumen, may be colored a unique color to indicate the lumen size (e.g., green may indicate a maximum lumen size for delivery of an interventional device, yellow may indicate a smaller lumen size for delivery of an imaging or diagnostic catheter, and red may indicate a lumen with a lateral port). The proximal end region of the lumen 120 and / or the proximal opening 126 to the lumen 120 may be a first color, and the proximal end region and / or the proximal openings 136, 146 to the auxiliary lumens 130, 140 may be a second color different from the first color. The proximal end region of lumen 150 and / or the proximal opening 156 to lumen 150 may be a third color, different from either the first or second colors, to indicate that lumen 150 extends through the sidewall of the distal end region of sheath 110 and has a distal exit port 151 intended for deployment of an embolism protection device. The color may be combined with text or symbols.Any of a variety of combinations of proximal markings 127 are contemplated herein to easily identify the various lumens of sheath 110 in a manner that is easily identifiable by a user.

[0070] The hub 124 may incorporate a silicone slit valve or luer attachment for connection in a Tuohy-Borst fashion. Each lumen 120, 130, 140, 150 may incorporate a dedicated hemostatic device. The sheath 110 may incorporate an irrigation port 113 and / or an irrigation port luer attachment to allow the user to simultaneously irrigate all lumens with saline, therapeutic agents, and / or contrast media, record pressure, etc. The hub 124 of the arterial access sheath 110 may include a Y-arm for aspiration, to deliver contrast media or saline irrigation, and / or may be fluidly connected to a shunt, which provides a shunt lumen or pathway for blood to flow from the arterial access sheath 110 to a return site, such as a venous return site or collection reservoir. At this point, a retrograde or reverse flow blood flow condition may be established in at least a portion of the artery. The Y-arm is for inflating an occlusion balloon in the distal end region of the sheath via the inflation lumen (if an inflation lumen is present), and the hemostatic valve is for introducing an intravascular valve delivery system into the sheath.

[0071] Any of the sheaths described herein may provide suction to the artery through it. In this regard, the access sheath 110 may be connected to an aspiration source via the Y-arm to capture embolic debris that may otherwise enter the remaining head and neck vasculature or travel downstream and lodge in the peripheral vasculature. The aspiration source may be active, e.g., a myocardial aspiration source, a pump, a syringe. Alternatively, a passive flow condition may be established, e.g., by fluidly connecting the Y-arm to the shunt 112 (see FIG. 1) and connecting the shunt 112 to a low pressure source, such as an atmospheric or negative pressure collection reservoir, or a venous return site of the patient. The passive flow rate may be regulated, e.g., by controlling the restriction of the flow path in the shunt.

[0072] Any of the sheaths 110 described herein may be configured to pass or navigate bends in an artery without kinking. For example, when the access sheath 110 is introduced retrogradely through a transcarotid approach into the common carotid artery (either left or right) above the clavicle and below the carotid bifurcation, the elongated sheath body 115 is desirably flexible while retaining hoop strength to resist kinking or buckling. This is particularly important in procedures where the amount of sheath insertion into the artery is limited and / or where the insertion angle is steep, such as transcarotid access for patients with deep carotid arteries and / or short necks. In such cases, the stiffness of the sheath will tend to cause the tip of the sheath body to move toward the posterior wall of the artery. This creates a risk of injury from the insertion of the sheath body itself or from devices inserted into the artery through the sheath, such as a guidewire. The sheath body 115 is desirably configured to be bendable without kinking when inserted into the artery. The arterial access sheath 110 can be passed through a bend of 45 degrees or less that is located within 5 cm, 10 cm, or 15 cm of the arteriotomy measured through the artery. The sheath 110 is generally straight with or without an angled bend of about 20° at the tip. The angled bend at the tip can aid in navigation and delivery.

[0073] Any working portion of the arterial access sheath 110 described herein, such as the sheath body 115 that enters the artery, may be constructed of two or more layers. The inner layer may be constructed of a low friction polymer such as PTFE (polytetrafluoroethylene), HDPE, or FEP (fluorinated ethylene propylene) to provide a smooth surface for device advancement through the lumen. The outer jacket material may provide mechanical integrity to the inner layer and may be constructed of materials such as Pebax, thermoplastic polyurethane, polyethylene, nylon, etc. The inner and outer surfaces may be lubricious through the choice of material (PTFE, HDPE), coating (silicone, hydrophilic coating), and / or surface modification. A third layer may be incorporated between the inner layer and the outer jacket that may provide reinforcement. The reinforcement layer may prevent the sheath body lumen from flattening or kinking as the device passes through the bends in the vasculature. The reinforcement layer may also provide an unobstructed lumen for device access, as well as aspiration or backflow. In one embodiment, the sheath body 115 is circumferentially reinforced. The reinforcement layer may be made of metal, such as stainless steel, nitinol, nitinol braids, helical ribbon, helical wire, cut stainless steel, or a rigid polymer, such as PEEK. The reinforcement layer may be a structure, such as a coil and / or braid, or a tube that is laser cut or machined to provide flexibility. In another embodiment, the reinforcement layer may be a cut hypotube, such as a nitinol hypotube or a cut rigid polymer. The reinforcement of the elongate body 115 may be configured to improve longitudinal and torsional stiffness to provide near 1:1 movement of the sheath 110 from the proximal hub 124 to the distal tip 122.

[0074] Retention of the sheath may be accomplished, for example, by eyelets or other features on the proximal end region of the access sheath 110 that can secure the sheath to the patient once properly positioned.

[0075] Initial access may be achieved using a micropuncture kit including an access needle, an access guidewire, and a micropuncture cannula. The access needle, access guidewire, and micropuncture cannula may be adapted to be introduced into the carotid artery or another blood vessel via a carotid artery puncture, as described elsewhere herein. Puncture of the carotid artery may be performed, for example, percutaneously or by surgical cutdown. Once access to the vessel is established, an access sheath 110 may be inserted. The sheath guidewire may be inserted using a modified Seldinger technique or a micropuncture technique.

[0076] The access sheath 110 may be inserted with the aid of a lubricious tip sheath dilator configured for initial insertion over a sheath guidewire (e.g., 014, 018, 035). The sheath distal tip 122 may be configured such that when the access sheath 110 is assembled with the sheath dilator to form a sheath assembly, the sheath assembly is smoothly inserted over the sheath guidewire through the arterial puncture with minimal resistance. At least some areas of the sheath 110 may be provided with a lubricious or hydrophilic coating to reduce friction during insertion into the blood vessel. The distal coating may be limited to a distal end region of the elongate body 115 such that the coating facilitates insertion without compromising the safety of the sheath at the puncture site or the ability of the operator to firmly grip the sheath during insertion.

[0077] The elongate body 115 can vary in flexibility over its length. For example, the outer jacket may vary in durometer and / or material in various portions. Alternatively, the reinforcing structure or material may vary over the length of the sheath body. In one embodiment, the distal-most portion of the sheath body 115 has a portion that is more flexible than the remainder of the sheath body. For example, the bending stiffness of the distal-most portion is one-third to one-tenth of the bending stiffness of the remainder of the sheath body 115. For a sheath configured for a CCA access site, the flexible distal-most portion constitutes a significant portion of the sheath body 115 and can be expressed as a ratio. In one embodiment, the ratio of the length of the flexible distal-most portion to the total length of the sheath body 115 is at least one-tenth and at most one-half of the total length of the sheath body 115.

[0078] The features of the access sheath and delivery system described herein are useful not only for TAVR, but also for a variety of other interventional methodologies, such as, for example, treating coronary, renal, hepatic, thoracic, and abdominal aortic aneurysms. Although the methods described herein are described in the context of TAVR, it is understood that the sheaths described herein can be used in any of a variety of methods. The sheath 110 can be used to deploy any of a variety of devices through the first lumen 120, including prosthetic valves, heterogeneous porous stents with asymmetric braids or coils that create areas of low or high blood flow, palisade or branched devices, flow diverters configured to divert blood flow away from an aneurysm, fistula, or ruptured vessel and have areas that allow flow to healthy tissue, vascular protection devices incorporating asymmetric braids or differential lattice density, and the like. The sheath 110 may be used to deliver one or more of devices including fluids (e.g., contrast agents, therapeutic agents, etc.), diagnostic catheters, pigtail catheters, electrophysiological pacing leads, pressure measuring devices, small bore catheters, microcatheters, etc., and to perform aspiration through one or more auxiliary lumens 130, 140. The sheath 110 may be used to deploy an embolism protection device through a lumen 150 having a side port 151.

[0079] In one embodiment, a multi-lumen access sheath 110 is first inserted into the vascular system, either via a percutaneous puncture or a direct surgical cut-down and puncture of the carotid artery. The access sheath 110 can be introduced through the penetration so that the tip is directly down towards the aortic ostium, and optionally oriented so that the lumen 150 faces the target of the embolic protection device. The transcarotid approach to the aortic valve may be achieved via the LCCA or via the RCCA. FIG. 10C illustrates the LCCA approach. Once the access sheath is positioned and an embolic protection device is optionally deployed through lumen 150 via an occlusion, aspiration, and / or filter element, access to the aortic valve is gained via a guidewire (e.g., 0.035 inch or 0.038 inch guidewire) inserted into the sheath 110 through the first lumen 120 and directed down the ascending aorta, across the native aortic valve or a previously implanted bioprosthesis. A diagnostic catheter (e.g., a pigtail catheter) may be inserted through lumen 130 and routed above the aortic valve to allow for direct injection of contrast and visualization by fluoroscopy. Lumen 140 may be used at any time during the procedure to deliver additional support devices above the aortic valve, perform suction, and / or inject contrast. Prior to valve implantation, a pre-dilatation of the native aortic valve may be performed with an appropriately sized dilatation balloon, e.g., a valvuloplasty balloon. A guidewire may be used to position the balloon across the valve, inflate and deflate the balloon, and remove the balloon while keeping the guidewire stationary. The endovascular prosthetic valve and delivery system are then inserted through lumen 120 of access sheath 110 over the guidewire. The valve positioned on the delivery system may be threaded through access sheath 110 to the site of the native aortic valve. The prosthetic valve may be adjusted, if necessary, longitudinally along its long axis and / or circumferentially about its long axis until the desired alignment is achieved. The prosthetic valve is then deployed at or near the location of the native aortic valve. A carotid approach allows for greater circumferential control of the sheath 110 and prosthetic device, improving alignment precision.

[0080] At the end of the implantation step, the function of the implanted prosthetic valve can be assessed by ultrasound, contrast injection under fluoroscopy, or other imaging modalities. Depending on the design of the delivery system, the prosthetic valve may be adjusted as necessary to achieve optimal valve function and position before final deployment. The delivery system and guidewire are then removed from the access sheath 110. The diagnostic catheter is then removed from the access sheath 110. After removal of the delivery system and guidewire, suction may be continued through the lumen 140 to capture embolic debris trapped in the sheath tip, occlusion element, and / or filter element, while the embolic protection element is removed from the lumen 150. Various forms of embolic protection devices can be deployed, including occlusion elements, filters, occlusion balloons, and suction.

[0081] The access sheath 110 is then removed and the access site is closed. If the access was a direct puncture of a surgical incision, the vessel is closed by tying pre-placed sutures, manually suturing, or using a surgical vascular closure device, as described in more detail below. If the access was percutaneous, percutaneous closure methods and devices may be employed to achieve hemostasis at the access site. In one embodiment, a closure device is applied to the site of the penetration prior to introducing the arterial access sheath through the penetration. There are various types of closure devices.

[0082] The access sites mentioned above are the left or right common carotid artery. Other access sites are possible, such as the left or right subclavian artery or the left or right brachial artery. For example, the left or right subclavian artery, the left or right brachial artery, transfemoral approach, etc. Although these arteries may require a longer and / or more tortuous route to the aortic valve, they offer other advantages over carotid access, such as the ability to work away from the patient's head, avoidance of unfavorable neck anatomy, such as a history of carotid endarterectomy or other neck surgery, or radiation, and less risk in case of access site complications. Additionally, carotid disease or small carotid arteries may preclude common carotid access. At any of these access sites, occlusion, aspiration, and / or filtering of the head and neck vessels during TAVI can increase the speed and accuracy of the procedure and reduce the incidence of embolic complications.

[0083] In any of the methods described herein, if access to the carotid artery was via a surgical cutdown, the access site may be closed using standard vascular surgery techniques. Pars sutures may be placed prior to sheath insertion and used to tie off the access site after sheath removal. If the access site was percutaneous, a wide variety of vascular closure elements may be used. In one embodiment, the vascular closure element is a mechanical element including an anchor portion and a closure portion, such as a self-closing portion. The anchor portion may be comprised of a hook, pin, staple, clip, tine, suture, or the like, and is engaged to the exterior surface of the common carotid artery about the penetration to secure the self-closing element when the penetration is fully open. The self-closing element may also include a spring-like or other self-closing portion that closes the anchor portion upon removal of the sheath to draw the tissue of the arterial wall together to provide closure. Typically, no further measures need to be taken to close or seal the penetration, as the closure is sufficient. Optionally, however, it may be desirable to provide a secondary seal of the self-closing element after the sheath is withdrawn. For example, the self-closing element and / or the tracheal tissue in the region of the element may be treated with hemostatic materials such as bioabsorbable polymers, collagen plugs, adhesives, sealants, clotting factors, or other clotting promoters. Alternatively, the tissue or self-closing element may be sealed using other sealing protocols such as electrocautery, suturing, clipping, stapling, etc. Alternatively, the self-closing element may be a self-sealing membrane or gasket material that is attached to the outer wall of the vessel with clips, adhesives, bands, or other means. The self-sealing membrane may have an internal opening, such as a slit or cross cut, that is normally closed by blood pressure. Any of these self-closing elements may be designed for placement in an open procedure or may be deployed percutaneously.

[0084] In another embodiment, the vascular closure element is a suture-based vascular closure device. The suture-based vascular closure device can place one or more sutures across the vascular access site such that when the suture ends are tied after sheath removal, the sutures provide hemostasis at the vascular access site. The suturing can be performed prior to insertion of a procedural sheath through the arteriotomy or after removal of the sheath from the arteriotomy. The device can maintain temporary hemostasis at the arteriotomy after placement of the sutures and before and during placement of the procedural sheath, and can also maintain temporary hemostasis at the arteriotomy after withdrawal of the procedural sheath and before tying the sutures. Exemplary closure devices are described in U.S. Pat. No. 8,858,490, entitled "SYSTEMS AND METHODS FOR TREATING A CAROTID ARTERY," which is incorporated herein by reference in its entirety, and various other devices, systems, and methods that are related to and can be combined with the devices, systems, and methods disclosed herein.

[0085] In several aspects, the invention will be described with reference to the figures. However, certain aspects may be implemented without one or more of these specific details or in combination with other known methods and configurations. Numerous specific details, such as specific configurations, dimensions, steps, etc., are described herein to provide a thorough understanding of the embodiments. In other instances, well-known processes or manufacturing techniques have not been described in detail to avoid unnecessarily obscuring the description. Throughout this specification, references to "one embodiment," "embodiment," "one aspect," "one embodiment," "embodiment," and the like mean that the particular feature, structure, configuration, or characteristic described is included in at least one embodiment, aspect, or embodiment. Thus, the expressions "one embodiment," "embodiment," "one aspect," "one embodiment," "embodiment," and the like, which are placed in various places throughout this specification, do not necessarily refer to the same embodiment, aspect, or embodiment. Furthermore, particular features, structures, configurations, or characteristics may be combined in any suitable manner in one or more embodiments.

[0086] Relative terms are used throughout this specification to indicate relative positions or directions or orientations and are not intended to be limiting. For example, "distal" may indicate a first direction away from a reference point. Similarly, "proximal" may indicate a position in a second direction opposite the first direction. The use of terms such as "front," "side," and "back," as well as "anterior," "posterior," "caudal," and "sephalad," are used to establish a relative frame of reference and are not intended to limit the use or orientation of any of the devices described herein in various embodiments.

[0087] The term "about" refers to a range of values ​​including the stated value that one of ordinary skill in the art would consider to be reasonably similar to the stated value. In embodiments, "about" refers to within a range of standard deviation using measurements generally accepted in the art. In embodiments, "about" refers to a range of up to ±10% of the stated value. In embodiments, "about" includes the stated value.

[0088] Although many specifics are described herein, these should not be construed as limiting the scope of the claims or the scope that may be claimed, but rather as describing features specific to particular embodiments. Certain features described herein in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a particular combination and may initially be claimed as such, one or more features from the claimed combination may in some cases be excluded from the combination, and the claimed combination may relate to a subcombination or subcombination variant. Similarly, although operations are depicted in the figures in a particular order, this should not be understood as requiring such operations to be performed in the particular order depicted, or sequentially, or to perform all of the depicted operations to achieve desired results. Disclosed are only some examples, embodiments, aspects, and implementations. Variations, modifications, and extensions of the described examples, implementations, and other implementations may be made based on the disclosed content.

[0089] In the above description and in the claims, phrases such as "at least one of" or "one or more of" may appear following a conjunctive list of elements or features. The term "and / or" may appear following a list of two or more elements or features. Such phrases are intended to mean any of the listed elements or features individually, or any of the listed elements or features in combination with any of the other listed elements or features, unless otherwise implicitly or explicitly contradicted by the context in which they are used. For example, the phrases "at least one of A and B," "one or more of A and B," and "A and / or B" are intended to mean, respectively, "A alone, B alone, or A and B together." A similar interpretation is intended for lists containing more than two items. For example, the phrases "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, and / or C" are intended to mean "A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together," respectively.

[0090] Use of the term "based on" above and in the claims is intended to mean "based at least in part on," allowing for unrecited features or elements.

Claims

1. 1. An arterial access sheath for performing transcatheter aortic valve repair, comprising: The arterial access sheath an elongate body having at least one lumen extending from a proximal opening to a distal opening; a proximal hub configured to couple to the proximal opening of the elongate body and remain external to the patient, the proximal hub including one or more proximal directional markings; and a radiopaque marker band embedded within the distal end region of the elongate body, the radiopaque marker band comprising spaced apart notches around the circumference of the distal end region circumferentially corresponding to the one or more proximal markings; and Equipped with the notches form radiopaque voids in the radiopaque marker band to form at least two radiopaque distal markings; An arterial access sheath, wherein an overlap of the at least two distal markings indicates a circumferential direction of the distal end region of the elongate body.

2. 10. The arterial access sheath of claim 1, wherein the elongate body has a length adapted to be introduced into an access site at a left or right common carotid artery or a left or right subclavian artery.

3. The arterial access sheath of claim 1 , wherein the shape of the distal markings forms a second, different shape when the at least two distal markings at least partially overlap.

4. The arterial access sheath of claim 3 , wherein the shape is a rectangle, a circle, a triangle, a diamond, an arrow, a hemisphere, or a square.

5. The arterial access sheath of claim 1 , wherein the at least two distal markings comprise at least two groups of distal markings.

6. The arterial access sheath of claim 5 , wherein the at least two groups are distinguishable from one another.

7. The arterial access sheath of claim 6 , wherein the at least two groups are distinguishable by the shape of the markers.

8. The arterial access sheath of claim 5 , wherein the at least two groups are distinguishable by the number of markers.

9. The arterial access sheath of claim 1 , wherein the radiopaque marker band comprises a polymer filled with one or more radiopaque materials.

10. The arterial access sheath of claim 9, wherein the radiopaque material is selected from the group consisting of tungsten, tantalum, barium sulfate, platinum, stainless steel, and gold.

11. The arterial access sheath of claim 1 , wherein the distal marking further comprises a button of radiopaque material protruding away from a sidewall of the distal end region of the elongate body.

12. The arterial access sheath of claim 1 , wherein the proximal markings are on a proximally facing surface of the proximal hub and are directly visible to a user.

13. The arterial access sheath of claim 1 , wherein the proximal marking comprises an adhesive marking, a painted marking, a molded marking, an etched marking, an embossed marking, or a printed marking on the proximal hub.

14. The arterial access sheath of claim 1 , wherein the elongate body has an asymmetry about its circumference and the proximal marking corresponds to the asymmetry.

15. The arterial access sheath of claim 1 , wherein the elongate body is non-circular in cross section.

Images