Patent Description:
The present disclosure generally relates to implantable medical devices and, more particularly, to aortic dissection implants, systems for their delivery, and their methods of use, the methods not being part of the invention.

Acute Aortic Dissections occur when a portion of the aortic intima (the inner most layer of the aorta) ruptures and systemic blood pressure serves to delaminate the intimal layer from the media layer resulting in a false lumen for blood flow that can propagate in multiple directions along the length of the aorta. AAD's impact approximately <NUM>,<NUM> patients in the US annually and are the most common catastrophe of the aorta, carrying very high mortality rates. Dissections that occur in the ascending portion of the aorta make up the majority of cases (<NUM>%) and are referred to as Type A, while those occurring in the descending aorta are called Type B. Although Type B AAD's can sometimes be managed medically, Type A dissections typically require immediate surgery. With mortality rates of <NUM>-<NUM>% per hour, <NUM>% of patients die within the first <NUM> to <NUM> hours, and <NUM>% die within two weeks of diagnosis.

<FIG> illustrates various Types of Acute Aortic Dissections (AADs) that may be referred to herein. Despite the high mortality associated with Type A dissections (<FIG>), a need remains for options to treat Type A dissections percutaneously. One option for treating Type A dissections includes a single-piece implant constructed of fabric with built-in reinforcement that resides only in the ascending aorta. <CIT> discloses an endovascular prosthesis for implantation in a body passageway. However, the shorter length of the implant compromises stability and this option does not address the downstream aspects of the head vessels and the initial portion of the descending aorta. Another option for treatment addresses the downstream portions with a bare-metal implant (no fabric) after the initial dissection in the ascending aorta is treated surgically. In this option, while the reinforcement need is addressed, a complete percutaneous solution is not provided. In some scenarios, attempts to treat a dissection with only a bare metal frame can be attempted, but with the risk that the frame can erode through the tissue or cause the fragile intima layer to dissect further.

Aortic grafts for treating aortic aneurysms may incorporate non-porous graft materials that seek to wall off the aneurysm from the main lumen of the graft and the aorta. Consequently, these grafts can be inappropriate for environments with branch vessels that require fenestration windows and/or other modification. As a result, attempting to apply aortic grafts designed for aneurysms to Type A dissections can be cumbersome or simply impossible. Accordingly, there exists an unmet clinical need for a less invasive, non-surgical solution to treat Type A AADs. There also remains a need for improved treatment for other types of Aortic Dissections, such as shown in <FIG>, as described further herein.

The invention relates to an aortic dissection system as defined by claim <NUM>.

In some aspects, the at least one layer may comprise a non-porous section configured to extend across at least a portion of the dissection.

In some aspects, the at least one layer may comprise a porous layer provided over the expandable support structure and a non-porous layer provided over the porous layer.

The expandable support structure is configured to extend from the descending aorta, through the aortic arch and into the ascending aorta. The at least one layer may comprise a porous section configured to permit blood flow from within the expandable support structure, through the porous section, and into the carotid arteries and the subclavian arteries. The at least one layer may comprise a non-porous section comprising an opening to allow blood to flow from within the expandable support structure, through the opening, and into the carotid and the subclavian arteries. The expandable support structure may be pre-formed with a curvature to conform to the aortic arch. The at least one layer may comprise a porous layer configured to substantially cover the expandable support structure from the descending aorta to the sinotubular junction and a non-porous layer partially covering the porous layer and configured to engage a wall of the ascending aorta on opposite sides of a tear of the dissection.

In some aspects, the expandable support structure can be configured to apply radial force to the descending aorta when expanded.

In some aspects, the aortic dissection implant can further comprise an expandable interface structure that may be configured to expand within the aortic root. The expandable interface structure can be configured to extend within the left and right coronary sinuses and distally past the left and right coronary ostia. The expandable interface structure can comprise a wire frame having three lobes. The at least one layer can extend over the expandable support structure and the expandable interface structure. The at least one layer can be configured to extend within the left and right coronary sinuses without blocking blood flow into the left and right coronary arteries.

In some aspects, the at least one layer can comprise a non-porous layer that may be configured to be positioned across at least a portion of the dissection and inflate with blood flow against the inner wall of the aorta adjacent the false lumen. The aortic dissection implant may further comprise at least one valve that can allow blood to enter a space within the non-porous layer but prevent blood from exiting the space.

In some aspects, the delivery system may be configured to sequentially deploy the at least one layer before the expandable support structure.

In some aspects, the system may further comprise one or more temporary longitudinal ribs that can be configured to be removable from the aortic dissection implant. The one or more temporary longitudinal ribs may be configured to maintain a circumferential space between the atraumatic outer surface of the at least one layer and the inner wall of the aorta.

In some aspects, the system can further comprise a temporary external coil that can be configured to surround the aortic dissection implant to maintain a circumferential space between the atraumatic outer surface of the at least one layer and the inner wall of the aorta.

In some aspects, the system can further comprise a suction port along the at least one layer. The suction port may be configured to apply vacuum to a circumferential space between the atraumatic outer surface of the at least one layer and the inner wall of the aorta when a vacuum applicator is applied to the suction port.

In some aspects of the disclosure, an aortic dissection implant for treating a dissection within an aorta of a patient is provided having the features described above and/or as described further below. Any of the aortic dissection implants as described above or as described further herein may comprise an expandable anchoring structure and an elongate tubular structure. The expandable anchoring structure is configured to be positioned within the aortic root of a patient and apply radial force to one or more of the sinuses of the aortic root and/or the sinotubular junction when expanded. The elongate tubular structure has a proximal end and a distal end. The proximal end of the elongate tubular structure is configured to be positioned in the descending aorta. The distal end of the elongate tubular structure can be configured to be positioned in the ascending aorta, the sinotubular junction, or the aortic root. The expandable anchoring structure can be connected to or forms the distal end of the elongate tubular structure. The elongate tubular structure can comprises an expandable support frame, a first porous layer, and a second porous layer. The expandable support frame may have a first length configured to extend from the descending aorta to at least the ascending aorta and curve along with a curvature of the aortic arch when expanded within the aorta. The first porous layer may be positioned over the expandable support frame and may have a second length configured to extend from the descending aorta at least partially through the aortic arch. The first porous layer may comprise an atraumatic outer surface. Expansion of the expandable support frame when positioned within the aorta may expand the first porous layer such that the atraumatic outer surface of the first porous layer presses against an interior surface of the aorta and applies a radial force at least to the descending aorta. The second non-porous layer may be positioned over the expandable support frame and may have a third length that is less than the first length. The second non-porous layer can comprise a first end and a second end that can be configured to be positioned on opposite sides of a tear of the dissection. The second non-porous layer can be inflatable when in use via blood flow through at least the expandable support frame to cause the non-porous layer to expand and seal against at least a portion of the dissection.

The aortic dissection implant of any of the preceding paragraphs or as described further herein can also include one or more of the following features. The second length of the first porous layer can be approximately the same as the first length of the expandable support frame. One or both of the first porous layer and the second non-porous layer can comprise a fabric material. The expandable support frame can comprise a wire, a coiled ribbon, a laser cut structure, or a braid. The atraumatic outer surface of the first porous layer can be configured to engage an interior surface of the aorta within the aortic arch and to allow blood flow from the aortic arch, through the first porous layer, and to the carotid and/or subclavian arteries. The expandable anchoring structure can comprise openings for allowing blood flow to the left and right coronary ostia. The expandable support frame can have a tubular shape when expanded and the expandable anchoring structure can have a cross-sectional dimension larger than a cross-section dimension of the expandable support frame when expanded. The expandable anchoring structure can comprise a trilobe shape. The second non-porous layer can be configured to be positioned over the expandable support frame within the ascending aorta.

In some aspects, the aortic dissection implant of any of the preceding paragraphs or as described further herein can further comprise a third layer between the first layer and the second layer. The third layer can provide for a one-way valve configured to allow blood to enter a space between the first layer and the second layer and prevent blood from exiting the space.

In some aspects of the disclosure, an aortic dissection implant for treating a dissection within an aorta of a patient is provided that comprises a proximal end, a distal end, an expandable support structure, at least one layer, and an expandable interface portion. The proximal end may be configured to be positioned within the descending aorta and the distal end may be configured to be positioned within an aortic root of the patient. The expandable support structure can be configured to extend from the descending aorta to the ascending aorta and curve along with a curvature of the aortic arch when expanded within the aorta. The at least one layer can be provided over the support structure. The at least one layer can comprise a porous section and a non-porous section. The porous section can be configured to curve along with the curvature of the aortic arch and allow blood to flow into the carotid and subclavian arteries of the patient. The non-porous section can be configured to engage a wall of the aorta on opposite sides of a tear in the aorta associated with the dissection. The expandable interface portion at the distal end of the aortic dissection implant can be configured to expand into contact with the aortic root.

The aortic dissection implant of any of the preceding paragraphs or as described further herein can also include one or more of the following features. The expandable support structure may comprise a coiled wire, a coiled ribbon, a laser cut structure, or a braid. The expandable support structure may be formed from one or more of a metal, a polymer, a biological material and a bio-absorbable material. The expandable support structure may comprise a tubular wire frame. the at least one layer may comprise a single layer having variable porosity. The at least one layer may comprise a tubular fabric layer. The at least one layer may comprise a tubular layer that may have radial support features at proximal and distal ends thereof. The expandable interface portion may be contiguous with the at least one layer. The expandable interface portion may be configured to extend within the left and right coronary sinuses and distally past the left and right coronary ostia. The expandable interface portion may comprise openings for allowing blood flow to the left and right coronary ostia. The expandable interface portion may comprise a wire frame having three lobes. The expandable support structure may be a separate structure from the expandable interface portion. The expandable support structure may be connected to the expandable interface portion by the at least one layer. The expandable support structure and the expandable interface portion may be formed from a single wire. The at least one layer may comprise a porous layer that may be configured to substantially cover the expandable support structure from the descending aorta to the sinotubular junction and a non-porous layer that may partially cover the porous layer and may be configured to engage a wall of the aorta on opposite sides of a tear of the dissection. The system may further comprise an expandable portion that may be proximal to the expandable interface portion. The expandable portion may be configured to radially expand against the sinotubular junction.

In some aspects, a method of treating a dissection with an aorta of a patient is disclosed. The method can comprise: delivering an aortic dissection implant in a collapsed configuration percutaneously into a patient to a treatment location within the aorta; and expanding the aortic dissection implant to an expanded configuration within the aorta. After expansion of the aortic dissection implant, a non-porous section of the aortic dissection implant can engage an inner wall of the aorta on opposite sides of a tear of the dissection.

The method of the preceding paragraph or as described further herein can also include one or more of the following features. The aortic dissection implant can comprise a portion that can be expanded within the descending aorta and can apply a radial force at least to the descending aorta. The aortic dissection implant can comprise a portion that can be expanded within the aortic root and can apply a radial force to one or both of the aortic root and the sinotubular junction. After expansion, a porous section of the aortic dissection implant can cover openings to the carotid and subclavian arteries to allow blood flow therethrough. After expansion, a porous section of the aortic dissection implant can cover one or both of the left and right coronary ostia to allow blood flow therethrough. The method can further comprise inflating the non-porous section with blood flow to expand the non-porous layer against the inner wall of the aorta. The method can further comprise reducing a false lumen in the aorta by drawing fluid from the false lumen through natural fenestrations of the aorta.

In some aspects, a dual-layer implant for a blood vessel is disclosed that comprises a first implant layer and a second implant layer. The first implant layer may have an atraumatic outer surface and a first resting diameter. The second implant layer, may be separate from the first implant layer, and may have a second resting diameter that is greater than the first resting diameter. The second implant layer may be configured to be disposed interior to the first implant layer and to expand the first implant layer such that the atraumatic outer surface of the first implant layer presses against a surface of the blood vessel.

The dual-layer implant of the preceding paragraph can also include one or more of the following features. The first implant layer can be a tubular layer having a central lumen that can be configured to receive the second implant layer and to coincide with a true lumen of the blood vessel. The first implant layer can be a fabric layer. The second implant layer can comprise a coil. The coil can be a metal coil. The metal coil can comprise a coil retention feature that can be configured to engage with a coil retention structure of a delivery system and to release from the coil retention structure upon implantation of the second implant layer. The first implant layer and the second implant layer can be bendable to conform to an aortic arch. The first implant layer can include at least a portion that is porous to allow blood flow from the aortic arch, through the first implant layer, to the carotid or subclavian arteries. The dual-layer implant may further comprise an interface structure for interfacing with the native anatomy of the aortic valve cusps. The interface structure may include fenestrations for allowing blood flow to the left and right coronary ostia. The first implant layer may further comprise a non-porous portion and at least one temporary rib. The dual-layer implant may further comprise at least a portion that is radiopaque. The dual-layer implant may further comprise at least a portion that is echogenic. The first implant layer may comprise radial support structures at opposing ends thereof.

In some aspects, a system is disclosed that comprises the dual-layer implant of any one of the preceding paragraphs and a delivery system. The delivery system can be configured to deliver the first implant layer and the second implant layer together into the blood vessel.

In some aspects, a system is disclosed that comprises the dual-layer implant of any one of the preceding paragraphs and a delivery system. The delivery system may be configured to decouple the first implant layer and the second implant layer for asynchronous deployment and release into the blood vessel.

In some aspects, a method of implanting a dual-layer implant is disclosed. The method can comprise: inserting the implant percutaneously into the femoral artery of a patient and advancing the implant into the patient's aorta; retracting an outer sheath to deploy a first implant layer and allow the first implant layer to radially expand to a first resting diameter within the aorta, manipulating a retention structure to deploy a second implant layer, within a lumen of the first implant layer, from the retention structure; further manipulating the retention structure to cause the second implant layer to radially expand to a second resting diameter that is greater than the first resting diameter to cause the first implant layer to radially expand beyond the first resting diameter into contact with the aorta.

The method of the preceding paragraph can also include one or more of the following features. Retracting the outer sheath may deploy deployment arms that may cause the first implant layer to radially expand, and wherein the method further comprising, removing the deployment arms after deployment of the second implant layer. The dual-layer implant may include any of the features of any of the preceding paragraphs. The first implant layer may further comprise a radial support feature at a distal end or a proximal end. The method may further comprise: maintaining, with longitudinal support ribs coupled to the first implant layer, a space between an outer surface of the first implant layer and an interior wall of the aorta; and applying a vacuum to a channel that extends from an inner surface of the first implant layer to the outer surface of the first implant layer to reduce a false lumen in the aorta by drawing fluid from the false lumen through natural fenestrations of the aorta. The method may further comprise removing the longitudinal support ribs.

In the following detailed description, numerous specific details are set forth to provide a full understanding of the present disclosure. It will be apparent, however, to one ordinarily skilled in the art that embodiments of the present disclosure may be practiced without some of the specific details. In other instances, well-known structures and techniques have not been shown in detail so as not to obscure the disclosure.

Aspects of the subject disclosure are directed to aortic dissection implants, such as dual layer implants, that may be utilized in the treatment of aortic dissections, as well as systems and methods involving the same. In accordance with certain aspects of the subject disclosure, a dual-layer implant is provided that can be used for treatment of Type A Acute Aortic Dissections (AADs), or any other abdominal or thoracic aortic dissection, rupture, or aneurysm. The dual-layer implant can include a first implant layer that forms a soft, atraumatic outer layer to directly contact the intima of the aorta. The dual-layer implant can also include a second implant layer, which can be deployed after or in sequence with the first layer, and that provides reinforcement and direct apposition of the first layer against the intima. Because the first implant layer (e.g., a graft layer) and the second implant layer (e.g., a support structure) in some aspects are not attached together prior to delivery, and can thus be delivered in two separate and/or overlapping steps, the dual-layer implant is sometimes described herein as a dual-layer asynchronous implant. That is, the delivery system for the dual-layer implant, as described in further detail hereinafter, can deploy the two layers together, or can decouple the two layers to allow for asynchronous deployment and release. It will be appreciated that the dual-layer implant as described herein may also be manufactured with the first implant layer provided over the second implant layer, such that the two layers are delivered to a treatment location as a single unit.

<FIG> illustrate an aortic dissection implant <NUM> for use in an aortic dissection system <NUM> according to certain aspects. The aortic dissection implant <NUM> can comprise a first implant layer <NUM>, such as a porous and/or non-porous material as described further herein, that may be reinforced with a second implant layer <NUM>, such as a coil, braid, wire frame, Z-stent or any other reinforcement structure as described herein. As used herein, non-porous refers to any material or structure with no openings or openings sufficiently small to prevent blood flow within the ranges of physiological pressures. The aortic dissection system <NUM> may comprise the aortic dissection implant <NUM>, and a delivery system which may include an outer sheath <NUM> and/or one or more other delivery components. <FIG> illustrates a system <NUM> including a dual-layer implant <NUM> packaged for implantation within an outer sheath <NUM> coupled to a nose cone <NUM> and mounted to or delivered over a guidewire <NUM>. System <NUM> is shown in partial cross section in <FIG>, so that the first implant layer <NUM> and the second implant layer <NUM> can be seen. As described in further detail hereinafter, in the delivery configuration shown in <FIG>, first implant layer <NUM> and second implant layer <NUM> are compressed within outer sheath <NUM> for implantation. Outer sheath <NUM> can be retracted relative to first implant layer <NUM> for deployment of first implant layer <NUM>. <FIG> also illustrates a retention layer or catheter <NUM> for second implant layer <NUM>, illustrated in this embodiment as a coil. Retention layer or catheter <NUM> constrains second implant layer <NUM> in the compressed configuration of <FIG> and is manipulable (e.g., rotatable, retractable or otherwise) for controlled deployment of second implant layer <NUM>. In various examples, dual-layer implant <NUM> is described herein for treatment of Type A dissections. However, it should be appreciated that dual-layer implant <NUM> can be applied to Type B dissections and all types of aortic aneurysms as well. It should also be appreciated that in other implementations, implant <NUM> may comprise more than two layers (e.g. with a secondary graft layer <NUM> inside of support layer <NUM> or a secondary support layer inside of support layer <NUM>).

It has been discovered that it is not necessary to "wall-off" the dissected area in the case of AADs, as long as the layers at the source of the dissection can be re-approximated along its length in order to prevent pressure from propagating through the false lumen and to instead direct that pressure through the true lumen. In fact, providing a first implant layer <NUM> formed from a porous material allows several advantages during deployment (e.g. by not obstructing blood flow), allows for healthier functionality of the aorta, and offers the ability to more easily deal with branch vessels that may be encountered. It is also understood that the aortas in patients with the conditions described herein are very fragile so care must be given in some aspects to make the implant as atraumatic as possible. In some aspects, separating the implant <NUM> into a soft, atraumatic first layer <NUM> with a secondary reinforcement layer <NUM> that is controllably and sequentially deployed asynchronously against the first layer <NUM> (e.g., after the first layer is in place or prior to the first layer <NUM> being fully deployed), helps to improve safety. While the native aorta provides its support from the outermost layer, the implant <NUM> provides support from the inner-most layer <NUM> with the softer layer <NUM> on the outside to appose the soft intima layer of the native aorta.

System <NUM>, initially in the configuration shown in <FIG>, can be inserted percutaneously into the femoral artery and advanced into the patient's aorta <NUM>. As shown in <FIG>, depending on the desired location of treatment and implantation, the system <NUM> may be advanced from one of the iliac arteries <NUM> to the descending aorta <NUM>, and may continue around the aortic arch <NUM>, to the ascending aorta <NUM>, and into the aortic root <NUM>. As used herein, the proximal end of the implant <NUM> or the system <NUM><NUM> is the end closest to the operator and farthest from the aortic root <NUM>, and the distal end of the implant <NUM> and the system <NUM> is the end farthest from the operator and closest to the aortic root <NUM>.

In the delivery configuration of <FIG>, initial outer layer <NUM> is retained within outer sheath <NUM>, while the reinforcement layer <NUM> is retained under torsional tension with a mechanism (e.g., by coil retention structure <NUM>) that is arranged to be unwound or unthreaded to allow the secondary implant layer <NUM> to deploy. Other mechanisms could be utilized to maintain the reduced diameter of each layer during delivery and allow for controlled diametric expansion upon deployment. For example, second implant layer <NUM> can be alternatively constrained within an inner sheath that can be retracted linearly for deployment of second implant layer <NUM>. Locking mechanism <NUM> is provided to maintain connection with the delivery system and allow for repositioning, recapturing and/or removal of implant <NUM>, if needed, prior to full deployment of the implant.

<FIG> illustrates a perspective view of one example of first implant layer <NUM>, in accordance with aspects of the disclosure. First implant layer <NUM> can be formed from fabric, metal, polymer or a biological tissue (as examples). First implant layer <NUM> is sized such that it is capable of reaching a diameter just slightly beyond that of the native aorta (e.g., a maximum diameter of about <NUM> to <NUM>) when fully expanded with the reinforcement layer <NUM> inside. In some aspects, first implant layer <NUM> can have a resting diameter of <NUM> (or about <NUM>), and may be stretchable or can expand (e.g., by second implant layer <NUM>) to an expanded diameter of <NUM> (or about <NUM>) to <NUM> (or about <NUM>). First implant layer <NUM> may include one or more porous regions <NUM> that allows for blood to flow through that region (e.g., if the porous region is deployed across the ostia of a branch vessel). The material of first implant layer <NUM> may be flexible enough to accommodate the curvature of the aortic arch. In some implementations, the entire length of first implant layer <NUM> could be porous. In other implementations, the entire length of first implant layer <NUM> may be non-porous. In still other implementations, the level of porosity may vary throughout the length of first implant layer <NUM>. In still other embodiments where <NUM> has a given thickness, the porosity of the inner surface may differ from the porosity along the outer surface.

First implant layer <NUM> may be formed from a fabric that is woven in an open honey-comb shape (as shown in <FIG>) or in one or more other configurations that afford a wall thickness <NUM>, such that the outer diameter of layer <NUM> can be disposed against the inside of the aorta, and the inner diameter can be compressed against the outer diameter when the inner reinforcement layer <NUM> is expanded inside layer <NUM>, to distribute the radial load and avoid putting excessive pressure on the aortic wall.

For example, in other embodiments first implant layer <NUM> may be formed with an open woven pattern, a laser cut pattern, a braided configuration, or any other form that allows for blood to flow through one or more porous portions <NUM>. In some cases, the porosity of first implant layer <NUM> varies around the circumference and/or along the length of the first implant layer <NUM> to achieve targeted levels of porosity against different portions of the patient's anatomy. For example, the porosity of the material itself can vary with position on layer <NUM>, or holes, openings, or other fenestrations can be formed in the material of layer <NUM>.

Additionally, the first implant layer <NUM> or portions of the first implant layer <NUM> may be formed of a fabric or polymer that is porous and/or non-porous. The first implant layer <NUM> could comprise one of or a combination of polyester, nylon, polytetrafluoroethylene (PTFE), or silicone.

In the example of <FIG>, first implant layer <NUM> includes radial support features <NUM> and <NUM>, respectively at its distal and proximal ends. Radial support features <NUM> and <NUM> may have a radial compressibility that is less than the radial compressibility of the intervening length of first implant layer <NUM>. Radial support features such as radial support features <NUM> or <NUM> can be provided to help secure the position of first implant layer <NUM> prior to the deployment of second implant layer <NUM>. Radial support features <NUM> and/or <NUM>, and/or other portions of implant <NUM> may be radiopaque and/or echogenic so as to allow visualization under fluoroscopy and/or ultrasound intra-procedurally. Radial support features may be provided on an outer surface, an inner surface, or embedded within the implant layer <NUM>. Examples of radial support features include wire frames, coils, braids, and stents have a Z-shape, zig-zag pattern, or more complex geometries, e.g., laser cut from a self-expanding shape memory alloy. Radial support features may have a cylindrical shape, a frustoconical shape or other shapes.

As described in further detail hereinafter (see, e.g., <FIG> and the associated description), in some implementations, the distal shape (e.g., including radial support feature <NUM>) of first implant layer <NUM> (or one or more additional interface structures at the distal end of first implant layer <NUM>) may be arranged to interface with the native anatomy of the aortic valve cusps and left and right coronary ostia, in circumstances in which it is desirable to engage as deep as possible within the aortic root without impacting aortic valve function and without obstructing flow to the coronaries. As used herein, aortic valve cusps are intended to include the sinuses of the aortic root. In some implementations, the distal end of the implant may incorporate a prosthetic aortic heart valve (e.g., coupled to or configured to interface with first implant layer <NUM>).

Second implant layer <NUM> is a reinforcement layer that provides hoop strength and radial force beyond that of the first implant layer <NUM>, and serves to enhance the apposition of the first implant layer <NUM> against the intima. Second implant layer <NUM> may be formed from one or more of a metal (e.g., stainless steel, nitinol, or the like), a polymer, a biological material, a bio-absorbable material, and/or other suitable materials. <FIG> shows a perspective view of second implant layer <NUM>, in one implementation. Second implant layer <NUM> may be a coiled wire forming a wire frame, a coiled ribbon as in the example of <FIG>, a laser cut structure, a braid or may be formed in another open configuration that can accommodate the curvature of the native aorta. Second implant layer <NUM> may be completely or partially radiopaque and/or echogenic to enhance visualization intra-procedurally.

<FIG> illustrates a perspective view of the second implant layer <NUM>. The second implant layer <NUM>, for example, may be formed as a coiled structure having a pitch of approximately <NUM>, an overall length of between approximately <NUM>-<NUM>, a cross-sectional width of approximately <NUM>, and a resting diameter of approximately <NUM> to approximately <NUM>. Second implant layer <NUM> may be radially compressible (e.g., by a compressive force from a portion of the aorta) to a diameter of approximately <NUM>. As illustrated in <FIG>, second implant layer <NUM> may also be twisted to a further reduced insertion diameter by coil retention structure <NUM>. In the example of <FIG>, second implant layer <NUM> is formed from a coiled ribbon having a cross-sectional height of approximately <NUM>.

<FIG> also shows a proximal release feature <NUM> for second implant layer <NUM>. In the example of <FIG>, proximal release feature <NUM> is an opening at the proximal end of second implant layer <NUM>. When twisted into the insertion diameter within coil retention structure <NUM>, proximal release feature <NUM> may be engaged with a corresponding feature on the interior of coil retention structure <NUM> (e.g., to prevent rotation of the proximal end of second implant layer within coil retention structure <NUM> while the proximal end is within coil retention structure <NUM>). As described in further detail in connection with <FIG>, proximal release feature <NUM> may disengage from the corresponding feature on the interior of coil retention structure <NUM> as the proximal end of second implant layer <NUM> exits coil retention structure <NUM> to complete the implantation of implant <NUM>. Although second implant layer <NUM> is depicted in <FIG> as a single coil, in other implementations, second implant layer <NUM> may be implemented as double-coil (e.g., with a parallel pitch or an opposite pitch to form a helix) to provide additional support with opposite pitch to form a helix. In still other implementations, second implant layer <NUM> can be formed by a coarse braid with multi-fillar construction, a single or multiple piece wire form structure, or a laser cut structure.

<FIG> illustrates a perspective and partial cross-sectional view of implant <NUM> (in partial cross-section for clarity) midway through implantation in the true lumen <NUM> of a blood vessel <NUM> having a false lumen <NUM> associated with a dissection <NUM>. The dissection <NUM> can have an entry tear and may have one or more re-entry tears. In the configuration of <FIG>, outer sheath <NUM> has been partially retracted to allow the first implant layer <NUM> to expand to its resting diameter within true lumen <NUM> such that the distal end of first implant layer <NUM> (and distal radial support feature <NUM>) is distal to the dissection <NUM> and the proximal end of first implant layer <NUM> is proximal to dissection <NUM>. In the configuration of <FIG>, coil retention structure <NUM> has also been rotated to cause a distal portion of second implant layer <NUM> to exit an opening <NUM> at the distal end of coil retention structure <NUM> to begin to expand to its resting diameter at which second implant layer <NUM> presses first implant layer <NUM> against the intima of blood vessel <NUM>. In other embodiments, the retention structure <NUM> may simply be withdrawn as a sheath in order to expose the second implant layer <NUM> and allow for its expansion.

From the configuration of <FIG>, implantation of implant <NUM> can be completed by further withdrawing outer sheath <NUM> beyond the proximal end of first implant layer <NUM> to allow radial support feature <NUM> to exit the sheath and expand to its resting diameter, and further twisting coil retention structure <NUM> until second implant layer <NUM> fully exits through opening <NUM> (and coil retention feature <NUM> releases from the corresponding internal feature of coil retention structure <NUM>). Locking features <NUM> may prevent second implant layer <NUM> from pulling or sliding proximally on first implant layer <NUM> during deployment of second implant layer <NUM>.

In this way, deployment of the outer layer <NUM> is initiated first while maintaining the ability to recapture layer <NUM> up to any point prior to full release. In implementations in which the material of layer <NUM> is porous, blood pressure collecting inside the implant is avoided, and the deployment of implant <NUM> can proceed at a measured pace. Once the distal end of the outer implant layer <NUM> has been expanded, the user has the option to continue to deploy the outer layer <NUM> or begin to release a portion of the reinforcement layer <NUM>, to further stabilize the position of the first layer <NUM>. If desired, the majority of outer layer <NUM> may be released from sheath <NUM> before the deployment of the reinforcement layer <NUM> is initiated.

At the beginning of deployment of second implant layer <NUM>, the coil retention structure <NUM> may be twisted such that a distal portion of second implant layer <NUM> can emerge from opening <NUM>. After continued rotation of coil retention structure <NUM>, the majority of second implant layer <NUM> can emerge from coil retention structure <NUM>.

In some implementations, system <NUM> may include delivery support arms between the initial graft layer <NUM> and the secondary support layer <NUM> during delivery. <FIG> illustrates a perspective view of example delivery support arms <NUM>, showing four arms. Any number of arms may be provided, such as three or more arms. In order to temporarily expand the graft layer <NUM> and provide apposition against the intima of the aorta prior to the expansion and secondary support layer <NUM> to ensure desired location and effect, delivery support arms <NUM> can be provided in system <NUM>. As shown in <FIG>, multiple angularly separated delivery support arms <NUM> may extend from a common base <NUM> of a delivery support structure <NUM>.

<FIG> illustrates system <NUM>, in the delivery state of <FIG>, in a configuration in which system <NUM> includes delivery support arms <NUM>. Only two delivery support arms <NUM> are shown for clarity. As illustrated in <FIG>, delivery support arms <NUM> are configured to expand without external assistance as an outer sheath <NUM> is withdrawn. Base <NUM> may be coupled to locking mechanism <NUM> and/or other portions of the delivery system such that delivery support arms <NUM> move proximally as the delivery sequence progresses (e.g., during deployment of second implant layer <NUM>). Upon full release of both implant layers <NUM> and <NUM>, outer sheath <NUM> is advanced interior to the two deployed layers, in order to recapture the delivery support arms for removal. In the example of <FIG>, delivery support arms <NUM> extend to the end of first implant layer <NUM>. However, delivery support arms <NUM> can be provided that are shorter than the distalmost end of second implant layer <NUM>. This arrangement of delivery support arms <NUM> can help ensure that delivery support arms <NUM> are not captured between second implant layer <NUM> and first implant layer <NUM> when second implant layer <NUM> is deployed.

<FIG> and <FIG> illustrate, simply for convenience, deployment of implant <NUM> in a substantially straight portion of blood vessel <NUM>. However, it should be appreciated that first implant layer <NUM> and second implant layer <NUM> as described allow implant <NUM> to be deployed in curved portions of a blood vessel, and/or in portions of a blood vessel having a varying size.

For example, <FIG> illustrates implant <NUM> deployed within the aortic arch <NUM>. The implant as shown in <FIG> may be a sequentially deployed implant as described above, or it may be delivered as a single unit. As shown in <FIG>, implant <NUM> comprises an elongate body having a proximal end <NUM> positioned within the descending aorta <NUM> and a distal end <NUM> positioned within the aortic root <NUM>. The implant <NUM> comprises an expandable reinforcement structure, such as second implant layer <NUM> described above or any of the other reinforcement structures described herein, that extends from the proximal end <NUM> in the descending aorta <NUM> to or near the distal end <NUM> within the aortic root <NUM>. An interface portion <NUM> is provided at the distal end <NUM> of the implant <NUM>, which may be expandable within the aortic root <NUM> to anchor and secure the implant <NUM>. The interface portion <NUM> may comprise an expandable wire frame and may be part of or separate from the reinforcement structure extending through the ascending aorta and descending aorta. Provided over the reinforcement structure are one more outer layers, such as implant layer <NUM> described above or any of the other layers described herein for covering the reinforcement structure and/or for contacting an inner wall of the aorta. For example, a porous implant layer <NUM> may extend from the proximal end <NUM> to the distal end <NUM> over the entire or substantially the entire reinforcement structure, optionally including the interface portion <NUM>.

As shown in <FIG> (in partial cross-section for clarity), both first implant layer <NUM> and second implant layer <NUM> are curved along with the curvature of aortic arch <NUM>, and fenestrations <NUM> in first implant layer <NUM> allow blood flow through first implant layer <NUM> into the carotid and subclavian arteries <NUM>. In some embodiments, the first implant layer <NUM> has a porous section <NUM> configured to be located within the aortic arch <NUM> to allow blood to flow into the carotid and subclavian arteries <NUM>. The implant <NUM> may further comprise, as part of the first implant layer <NUM> or as an additional layer, a non-porous section <NUM> located distal to the porous section <NUM> of the first implant layer <NUM>. The non-porous section <NUM> can be configured to engage a wall of the aorta adjacent to the false lumen <NUM> and over the entry tear of dissection <NUM>. In some embodiments, the first implant layer <NUM> is entirely porous. In some embodiments, the non-porous section <NUM> is a separate layer provided over the first implant layer <NUM> that is entirely non-porous.

<FIG> also shows how an interface portion <NUM> (e.g., contiguous with or coupled to first implant layer <NUM> and/or the second implant layer <NUM>) can be provided at the distal end of implant <NUM>. As shown, interface portion <NUM> is configured to conform to the native anatomy of the aortic valve cusps, e.g., to the sinuses of the aortic root, and includes fenestrations <NUM> for the left and right coronary ostia. As illustrated, the interface portion <NUM> may comprise an expandable wire frame having three lobes, each lobe configured to be positioned in and expandable to engage with one of the sinuses of the aortic root. Any or all of the lobes may be partially or entirely covered with a porous material or non-porous material, such as porous material of the first implant layer <NUM> or non-porous material of the additional implant layer <NUM>. As illustrated, the lobes in the left coronary and right coronary aortic sinuses may extend distally beyond the left and right coronary arteries <NUM>, <NUM>, respectively. When covered with porous material, blood will be allowed to flow through the porous material covering these lobes into the left and right coronary arteries.

<FIG> illustrates a perspective view of another aspect of an implant <NUM> comprising a first implant layer <NUM> in a dual-layer honeycomb fabric implementation with an elongate opening <NUM> (e.g., for alignment with the carotid and/or subclavian arteries). <FIG> illustrates a partial cross-sectional view of first implant layer <NUM> deployed within the aortic arch. As shown in <FIG>, the elongate opening <NUM> may align with the carotid and subclavian arteries such that blood may flow through the elongate opening <NUM> and into the arteries. The layer <NUM> in this embodiment may be non-porous to prevent blood from flowing into the dissection <NUM>. <FIG> illustrates the implant <NUM> without a reinforcement structure or second implant layer <NUM>. <FIG> illustrates a partial cross-sectional view of an implant <NUM> comprising a first implant layer <NUM> like in <FIG> with second implant layer <NUM> provided within the first implant layer <NUM>. An interface portion <NUM> as described above may anchor the first implant layer <NUM> and/or the second implant layer <NUM> to the aortic root.

<FIG> illustrates an edge shape for interface portion <NUM> that can expand to conform to the native anatomy. The interface portion <NUM> may comprise a first expandable component <NUM>. For example, the interface portion <NUM> can comprise a first expandable component <NUM> that can be configured to be positioned within the aortic root of a patient and apply radial force to one or more of the sinuses of the aortic root when expanded. The first component <NUM> can comprise multiple lobes, such as three lobes to form a trilobe anchoring structure, wherein the lobes are configured to engage with each of the sinuses of the aortic root and apply radial force to secure the first component <NUM> to the aortic root. Additionally, as shown <FIG>, the interface portion <NUM> can comprise a second expandable component <NUM> proximal to the first expandable component <NUM> that can be configured to be positioned within the sinotubular junction and apply radial force to this junction when expanded. In different embodiments, the interface portion <NUM> can comprise either the first expandable component <NUM> or the second expandable component <NUM>.

Additionally, the shape of the first implant layer <NUM> at the interface portion <NUM> may be shaped such that the first implant layer <NUM> does not impede blood flow through the coronary ostia. As illustrated, the first implant layer <NUM> may extend distally from the ascending aorta into the left and right aortic sinuses to cover only part of the interface portion <NUM> in the left and right aortic sinuses, but may terminate proximal to the left and right coronary arteries to allow blood to flow therethrough. The first implant layer <NUM> may also extend distally from the ascending aorta into the non-coronary aortic sinuses and cover part or all of the interface portion <NUM> in the non-coronary aortic sinuses.

<FIG> illustrates one example of implant <NUM> during deployment in a portion of blood vessel <NUM> with a varying diameter, showing how second implant layer <NUM> is variably compressible (e.g., responsive to the radial strength of the walls of blood vessel <NUM>) to conform first implant layer <NUM> along the walls of the blood vessel.

<FIG> illustrate how, in some implementations, an implant <NUM>, <NUM> can include features that allow further obliteration of a false lumen <NUM>. <FIG> illustrates a cross-sectional view of a blood vessel having a true lumen <NUM>, a false lumen <NUM> associated with a dissection <NUM>, and natural fenestrations <NUM> adjacent to the false lumen <NUM>. In the examples of <FIG>, a first implant layer <NUM> is provided over a second implant layer <NUM> with a suction port <NUM> that provides a channel to which vacuum can be applied via a vacuum applicator <NUM>. The first implant layer <NUM> can comprise features as described above for other first implant layers or any of the other first implant layers described herein. Moreover, the second implant layer <NUM> may include features as described above for other second implant layers or any other reinforcement structures described herein. In this example, one or more longitudinal ribs <NUM> can be provided to maintain a circumferential space between the outer surface of layer <NUM> and the interior wall of the native aorta. The one or more longitudinal ribs <NUM> may extend axially along a length of the implant <NUM>, and may have a stiffness greater than that of the second implant layer <NUM>. The one or more longitudinal ribs may have a curvature or be bowed, thereby preventing the implant layer <NUM> from fully expanding. When the implant <NUM> is sealed around the dissection <NUM>, a vacuum may be applied to channel <NUM>. As shown in <FIG>, this causes the surrounding false lumen <NUM> to be reduced by drawing fluid from the false lumen <NUM> through the entry tear <NUM> and the natural fenestrations <NUM> of the native aorta. As shown in <FIG>, support ribs <NUM> can then be removed to allow for apposition of the implant surface to the native aorta against the media and adventitia layers, thereby minimizing the false lumen <NUM> and maximizing the cross-section of the true lumen <NUM>.

In some embodiments, implant <NUM> can include a solid, non-porous graft portion that can be used, for example, for Type B dissections that are in the descending aorta. In these examples, implant <NUM> maintains a suction lumen <NUM> that runs from the inner diameter of the graft to communicate with an area on the outer diameter of the graft adjacent to the false lumen <NUM>. Using temporary longitudinal support ribs <NUM> to maintain the space (see, e.g., <FIG>), a vacuum is drawn in space between the implant <NUM> and the false lumen <NUM> to attempt to empty out the false lumen <NUM> through the natural porosity <NUM> of the native aorta. Once the false lumen <NUM> is drawn down, then the support ribs <NUM> can be removed (see, e.g., <FIG>) and the implanted graft <NUM> can radially expand to its full diameter and further reduce the false lumen <NUM> which has been emptied of pooled blood as indicated with reduced false lumen <NUM> in <FIG>.

In the examples of <FIG>, a first implant layer <NUM> is provided over a second implant layer <NUM> with a suction port <NUM> that provides a channel to which vacuum can be applied via a vacuum applicator <NUM>. In this example, an external coil <NUM> can be wrapped around the outside of a central portion of the implant <NUM> and passed through the suction portion <NUM> and vacuum applicator <NUM>. The external coil <NUM> is provided to maintain a circumferential space between the outer surface of first implant layer <NUM> and the interior wall of the native aorta, so that when a vacuum is applied to port <NUM>, the surrounding false lumen <NUM> would be reduced by drawing fluid from the false lumen <NUM> through the entry tear <NUM> and the natural fenestrations <NUM> of the native aorta. As shown in <FIG>, the external coil <NUM> can then be removed to allow for apposition of the implant surface to the native aorta against the media and adventitia layers, thereby minimizing the false lumen <NUM> and maximizing the cross-section of the true lumen <NUM>.

In some embodiments, implant <NUM> can include a solid, non-porous graft portion that can be used, for example, for Type B dissections that are in the descending aorta. In these examples, implant <NUM> maintains a suction lumen <NUM> that runs from the inner diameter of the graft to communicate with an area on the outer diameter of the graft adjacent to the false lumen <NUM>. Using the temporary external coil <NUM> to maintain the space (see, e.g., <FIG>), a vacuum is drawn in space between the implant <NUM> and the false lumen <NUM> to attempt to empty out the false lumen <NUM> through the natural porosity <NUM> of the native aorta. Once the false lumen <NUM> is drawn down, then the external coil <NUM> can be removed (see, e.g., <FIG>) and the implanted graft <NUM> can radially expand to its full diameter and further reduce the false lumen <NUM> which has been emptied of pooled blood as indicated with reduced false lumen <NUM> in <FIG>.

<FIG> illustrate, simply for convenience, deployment of implant <NUM>, <NUM> in a substantially straight portion of blood vessel. However, it should be appreciated that first implant layer <NUM>, <NUM> and second implant layer <NUM>, <NUM> as described allow implant <NUM> to be deployed in curved portions of a blood vessel, and/or in portions of a blood vessel having a varying size.

Generally, porous versions of implant <NUM> may be useful for any Type A (I or II) dissections (see, e.g., <FIG>) that require extending through the head vessels, and can also be applied to some Type B incidents (see, e.g., <FIG>). The non-porous graft option <NUM>, <NUM> of <FIG> may be more applicable to certain Type B configurations. Variable porosity of layer <NUM>, <NUM>, <NUM> (e.g., one section solid, another segment porous, or different degrees of porosity) can be used to offer solutions for different dissection or aneurysm configurations.

<FIG> depict another embodiment of an aortic dissection implant <NUM>. <FIG> depicts an implant layer such as described above that comprises a generally tubular, expandable support structure that extends from a proximal end <NUM> to a distal end <NUM>. The embodiment of the expandable support structure depicted in <FIG> shows a wire frame or wire coil <NUM> with a zig-zag or Z-shaped pattern along a cylindrical portion <NUM> of the coil <NUM>. Additionally, the expandable support structure can comprise other patterns that are suited for being used to treat an aortic dissection. Furthermore, the expandable support structure may be a laser cut structure, a braid or may be formed in another open configuration that can accommodate the curvature of the native aorta. The expandable support structure may also be completely or partially radiopaque and/or echogenic to enhance visualization intra-procedurally. The cylindrical portion <NUM> of the coil <NUM> can be configured to extend from the descending aorta to the ascending aorta and curve along with a curvature of the aortic arch when expanded within the aorta.

At the distal end <NUM>, the implant <NUM> comprises an expandable anchoring structure <NUM> such as the interface portion described above. The expandable anchoring structure <NUM> may have an enlarged cross-sectional diameter when expanded as compared to the cylindrical portion <NUM>. The expandable anchoring structure <NUM> comprises one or more components. The expandable anchoring structure <NUM> comprises a first expandable component <NUM>, such as the first expandable component described above, that can be configured to be positioned within the aortic root of a patient and apply radial force to the sinuses of the aortic root when expanded. The first component <NUM> comprises three lobes to form a trilobe anchoring structure, wherein the lobes are configured to engage with each of the sinuses of the aortic root and apply radial force to secure the first component <NUM> to the aortic root. Additionally, as shown <FIG>, the expandable anchoring structure <NUM> can comprise a second expandable component <NUM> proximal to the first expandable component <NUM>, such as the second expandable component described above, that can be configured to be positioned within the sinotubular junction and apply radial force to this junction when expanded. The second expandable component <NUM> may have a frustoconical shape in some embodiments, with a smaller diameter proximal end and a larger diameter distal end, to provide a transition between the cylindrical portion <NUM> and the enlarged expandable component <NUM>. In different embodiments, the expandable anchoring structure <NUM> can comprise either the first expandable component <NUM> or the second expandable component <NUM>.

In some aspects, the wire frame <NUM> may be a continuous wire that forms the first expandable component <NUM>, the second expandable component <NUM> and the cylindrical portion <NUM>. In other aspects, the first expandable component <NUM>, the second expandable component <NUM> and the cylindrical portion <NUM> may be formed from separate wire frames. The wire frame <NUM> may be formed from one or more of a metal (e.g., stainless steel, nitinol, or the like), a polymer, a biological material, a bio-absorbable material, and/or other suitable materials. In some aspects, the wire frame <NUM> may have an overall length of between approximately <NUM>-<NUM>, a cross-sectional width or diameter of the wire of approximately <NUM>, and a resting diameter in the cylindrical portion <NUM> of approximately <NUM> to approximately <NUM>. The wire frame <NUM> may be radially compressible to a diameter of approximately <NUM> or less. The expandable anchoring structure <NUM> may have a diameter of approximately <NUM> to <NUM> when expanded.

<FIG> illustrate embodiments of the aortic dissection implant that comprises the wire frame <NUM> with a layer <NUM> provided either within (<FIG>) or over (<FIG>) the wire frame <NUM>. The layer <NUM> can extend from the proximal end <NUM> of the wire frame <NUM> to the distal end <NUM> of the wire frame <NUM>. In some embodiments, the layer <NUM> may cover the second expandable component <NUM> of the expandable anchoring structure <NUM> and part of the first expandable component <NUM> of the expandable anchoring structure <NUM>. This configuration allows for the coronary ostia to remain uncovered after implantation of the aortic dissection implant, which allows blood to flow freely through the ostia. In other embodiments, the layer <NUM> may extend to the distal end of the expandable anchoring structure <NUM>.

In some aspects, the layer <NUM> can be formed from fabric, metal, polymer or a biological tissue. The layer <NUM> is sized such that it is capable of reaching a diameter just slightly beyond that of the native aorta (e.g., a maximum diameter of about <NUM> to about <NUM>) when fully expanded with the wire frame <NUM> inside. In other implementations, the layer <NUM> can have a resting diameter of <NUM> and an expanded diameter of <NUM>. The material of the layer <NUM> may be flexible enough to accommodate the curvature of the aortic arch. In some implementations, the entire length of layer <NUM> could be porous. In other implementations, the entire length of layer <NUM> may be non-porous. In still other implementations, the level of porosity may vary throughout the length of layer <NUM>. For example, the portion of the layer <NUM> along a distal portion of the cylindrical portion <NUM> may be non-porous and the portion of the layer <NUM> along a proximal portion of the cylindrical portion <NUM> may be porous (e.g., as shown in <FIG>). In this embodiment, the porous section of the layer <NUM> can be configured to curve along the curvature of the aortic arch and allow blood to flow into the carotid and subclavian arteries of the patient. The non-porous section of this embodiment can be configured to engage with the wall of the aorta adjacent a false lumen associated with the dissection. The wire frame <NUM> provides hoop strength and radial force beyond that of the layer <NUM>, and serves to enhance the apposition of the layer <NUM> against the intima.

In some embodiments, the wire frame <NUM> shown in <FIG> can be created from a single piece of wire. <FIG> depicts the distal end <NUM> of the embodiment of the aortic dissection implant shown in <FIG>. The back portion of the second expandable component <NUM> and the frustoconical portion of the layer <NUM> covering the second expandable component are not shown in <FIG> for clarity. A distal portion <NUM> of the single wire can be located at the distal end <NUM> of the wire frame <NUM>. The single wire can be bent to form the trilobe structure of the first component <NUM> of the expandable anchoring mechanism. At a first transition portion <NUM> of the single wire, the wire can be bent in such a way to form the second component <NUM> of the expandable anchoring structure. As illustrated, the second component <NUM> may be made with the wire <NUM> forming a sine wave around a circumference of the implant. At a second transition portion <NUM> of the single wire, the wire can be bent to begin forming the Z-shaped or zig-zag pattern of the cylindrical portion <NUM> of the wire frame <NUM> following generally spiral or helical shaped path. After the wire frame <NUM> is formed, the distal portion <NUM> is crimped or welded to the first transition portion <NUM>. Additionally, at the proximal end <NUM> of the coil <NUM>, as shown in <FIG>, a proximal end of the single wire can be crimped or welded to the portion of the coil <NUM> directly distal to the proximal end of the single wire. In other embodiments, the coil <NUM> can comprise multiple wires welded together. In other embodiments, a single wire may extend from the distal (or proximal end) of the implant, to the other end, and back.

<FIG> illustrates a partial cross-sectional view of another embodiment of an implant <NUM> deployed within the aortic arch and extending between the descending aorta, through the ascending aorta, and into the aortic root. In this embodiment, the implant <NUM> may comprise a first layer <NUM>, a second layer <NUM>, and an expandable support structure <NUM>. The expandable support structure <NUM> may be similar to the wire frame <NUM> depicted in <FIG> and described in the foregoing paragraphs, or it may be similar to any of the earlier described embodiments of reinforcement structures. The expandable support structure <NUM> may comprise a cylindrical coil or wire frame that can comprise a sinusoidal wave pattern, Z-shape or zig-zag pattern. The expandable support structure <NUM> can be configured to extend from the descending aorta to the ascending aorta and curve along with the curvature of the aortic arch when expanded within the aorta. In some aspects, the distal end of the expandable support structure may comprise an expandable anchoring structure <NUM> as described above. In some embodiments, the expandable anchoring structure <NUM> can comprise an expandable trilobe structure <NUM> that can be configured to be positioned within the aortic root of a patient and apply radial force to the sinuses of the aortic root. In some embodiments, the expandable anchoring structure <NUM> may comprise a sinusoidal wave structure <NUM> that may be configured to be positioned within the sinotubular junction and apply radial force to the sinotubular junction. In the embodiment shown in <FIG>, the expandable anchoring structure <NUM> comprises both the expandable trilobe structure <NUM> and the sinusoidal wave structure <NUM>.

In some aspects, the implant <NUM>, and particularly the expandable support structure <NUM>, may be configured to expand within at least the descending aorta to press against and apply radial force to the inner wall of the descending aorta. In such embodiments, a diameter of the expandable support structure in at least a proximal portion thereof is larger than an inner diameter of the descending aorta. The implant <NUM> may also be configured such that a distal portion of the implant, and particularly a distal portion of the expandable structure, is smaller than an inner diameter of the ascending aorta.

The first layer <NUM> may be provided over the expandable support structure <NUM> and may be configured to extend from the proximal end of the expandable support structure <NUM> at least to the sinusoidal wave structure <NUM>. In some aspects, the first layer <NUM> can be formed from fabric, metal, polymer or a biological tissue, and may be made of any of the materials described above for layer <NUM>. The first layer <NUM> may be sized such that it is capable of reaching a diameter just slightly below that of the native ascending aorta (e.g., a maximum diameter of about <NUM>) when fully expanded with the expandable support structure <NUM> inside. In other implementations, the first layer <NUM> can have resting diameter of <NUM> and an expanded diameter of <NUM> such that it could be expanded by the support structure <NUM> to contact the inner most wall of the native descending aorta. The material of the first layer <NUM> may be flexible enough to accommodate the curvature of the aortic arch. In some implementations, the entire length of first layer <NUM> may be non-porous or the level of porosity may vary throughout the length of first layer <NUM>. In the embodiment of the aortic dissection implant shown in <FIG>, the entire length of first layer <NUM> is porous. The porosity of the first layer <NUM> could be configured to allow blood to flow into the carotid and subclavian arteries of the patient. The expandable support structure <NUM> provides hoop strength and radial force beyond that of the layer <NUM>, and serves to enhance the apposition of the layer <NUM> against the intima.

The second layer <NUM> may be provided over the first layer <NUM> and may be configured to contact the site of the aortic dissection and the aortic wall adjacent to the false lumen. In some aspects, the length of the second layer <NUM> may be less than the length of the first layer <NUM>. The second layer can extend along one of the lobes of the trilobe structure <NUM>, e.g., the lobe positioned in the non-coronary aortic sinus, and the other two lobes remain uncovered so that blood may flow through the coronary ostia. The second layer <NUM> can be formed from fabric, metal, polymer or a biological tissue, including any of the materials that may be utilized for the first layer <NUM>. In the embodiment of the second layer <NUM> shown in <FIG>, the entire length of the second layer <NUM> is non-porous.

In some embodiments, both ends of the second layer <NUM> may be sealed to the first layer <NUM> and the second layer <NUM> may be configured to expand like a balloon when blood flows through the implant, as indicated by the arrows in <FIG>. In particular, blood may flow through the first layer <NUM> and expand the second layer <NUM> such that there is space between the first layer <NUM> and the second layer <NUM>. The expanded diameter of the second layer <NUM> may be larger than the diameter of the first layer <NUM> (e.g., <NUM> for <NUM> versus <NUM> for <NUM>). The second layer <NUM> may remain inflated against the aortic wall such that the second layer <NUM> applies radial force to the aortic dissection site to seal the entry tear prevent blood from flowing into the false lumen. In some instances, an additional (third) layer that is non-porous may be disposed between the first porous layer <NUM> and the second non-porous layer <NUM> such that the third layer provides for a one-way valve that allows blood to enter the space between layers <NUM> and <NUM> but prevents it from exiting. This could be accomplished by laser cutting or otherwise creating gills, slots or flaps in the third layer that can open into the space during systole when blood pressure is highest but close against the first porous layer when that pressure is reduced during diastole preventing the blood from exiting.

In another embodiment, the aortic dissection implant can comprise a single layer that extends from the distal end to the proximal end of the expandable support structure. The single layer can comprise an inflatable non-porous section and a porous section proximal to the inflatable non-porous section. The inflatable non-porous section may be similar to the second layer <NUM> and the porous section may be similar to the first layer <NUM> shown in <FIG> and described in the foregoing paragraphs.

<FIG> illustrates another embodiment of an expandable support structure <NUM>. The expandable support structure <NUM> can comprise a braided configuration, as illustrated in <FIG>, and be configured to extend from the descending aorta to the ascending aorta and curve along with the curvature of the aortic arch when expanded within the aorta. In some aspects, the expandable support structure <NUM> may be formed from one or more of a metal (e.g., stainless steel, nitinol, or the like), a polymer, a biological material, a bio-absorbable material, and/or other suitable materials. In other aspects, the expandable support structure <NUM> may have length of approximately <NUM> and a diameter of approximately <NUM>. This embodiment of an expandable support structure <NUM> may be used in the different embodiments described in the foregoing paragraphs.

<FIG> depicts another embodiment of a first implant layer2000. The first implant layer <NUM> can comprise a layer <NUM>, a distal expandable support structure <NUM>, a proximal expandable support structure <NUM>, and an axial support structure <NUM>. In some aspects, the layer <NUM> may be non-porous and can be formed from fabric, metal, polymer or a biological tissue. The layer <NUM> can be cylindrical in shape and be configured to be flexible such that the layer <NUM> can conform to the shape of the ascending aorta. In some embodiments, length of the layer <NUM> may be adjusted at the time of the procedure prior to inserting the first implant layer <NUM> into the patient. In some aspects, the layer <NUM> can have a length of approximately <NUM> to <NUM> and a diameter of approximately <NUM> to <NUM>. The distal portion of the layer <NUM> may form a frustoconical shape in some embodiments, with a smaller diameter of approximately <NUM> at a proximal end and a larger diameter of approximately <NUM> at a distal end.

The distal and proximal expandable support structures <NUM>, <NUM> may be provided over or within the layer <NUM> and apply radial force to layer <NUM> against the intima of the ascending aorta when expanded within the ascending aorta. The distal expandable support structure <NUM> may comprise a zig-zag pattern. The proximal expandable structure <NUM> may comprise a sine wave pattern, a sine wave pattern and/or a trilobe pattern. In some aspects, the distal and proximal expandable support structures <NUM>, <NUM> may be formed from one or more of a metal (e.g., stainless steel, nitinol, or the like), a polymer, a biological material, a bio-absorbable material, and/or other suitable materials. The diameter of the distal expandable support structure <NUM> may be between <NUM> and <NUM>. The diameter of the proximal expandable support structure <NUM> may be approximately <NUM>.

The first implant layer <NUM> may also comprise an axial support structure <NUM>. The axial support structure <NUM> may be provided over, within, or interwoven into the layer <NUM>. The axial support structure <NUM> may extend between a distal end and a proximal end of the layer <NUM> and may provide reinforcement to the first implant layer <NUM>.

The first implant layer can be deployed within a patient's aorta to provide force against the site of an aortic dissection. Following the placement of first implant layer <NUM>, a second long-term support structure (e.g., the expandable support structure depicted in <FIG> or <FIG>) may be deployed inside of the first implant layer along the aortic arch and across the carotid and subclavian arteries to the descending aorta. Prior to deployment, the length and/or diameter of the first expandable support structure of <FIG> can be sized separately from the later deployed expandable support structure.

<FIG> illustrate another embodiment of the expandable support structure. This embodiment of the expandable support structure <NUM> may have a braided configuration, similar to the embodiment described in <FIG>, and be configured to extend from the descending aorta to the ascending aorta and curve along with the curvature of the aortic arch when expanded within the aorta. In some aspects, the expandable support structure <NUM> may be formed from one or more of a metal (e.g., stainless steel, nitinol, or the like), a polymer, a biological material, a bio-absorbable material, and/or other suitable materials. In other aspects, the expandable support structure <NUM> may have length of approximately <NUM> and a diameter of approximately <NUM>. This embodiment of an expandable support structure <NUM> may be used in the different embodiments described in the foregoing paragraphs.

<FIG> depicts the expandable support structure <NUM> in a curved orientation and <FIG> depicts the expandable structure <NUM> in a straight orientation. The expandable support structure <NUM> may comprise an anchoring mechanism <NUM> at the distal end and a cylindrical portion <NUM> proximal to the anchoring mechanism <NUM>. The anchoring mechanism <NUM> may comprise three lobes that can be configured to be positioned within the aortic root of a patient and apply radial force to the sinuses of the aortic root. The cylindrical portion <NUM> may be configured to extend from the descending aorta to the ascending aorta and curve along with the curvature of the aortic arch when expanded within the aorta.

In some embodiments, the aortic dissection implant, as described in the foregoing paragraphs, can be preformed during manufacturing. For example, the implant can be preformed to include a bend with a radius of curvature of approximately <NUM> and an angle of curvature of <NUM> degrees to <NUM> degrees. This bend can be configured to be positioned along the curvature of the aortic arch. In some embodiments that include trilobe anchoring structures, the preformed shape may be aligned with respect to the non-coronary aortic sinus (e.g. the major bend of the aortic arch could be approximately <NUM> degrees from the non-coronary aortic sinus). In other embodiments, specific features like the window <NUM> in <FIG> could also be aligned with the pre-formed curvature of the implant and/or specific trilobe features as noted above.

In some embodiments, the aortic dissection implant, as described in the foregoing paragraphs, may have variable dimensions to assist in securing and anchoring of the implant. For example, the implant in an expanded configuration may have a relatively larger diameter at its distal end (e.g., about <NUM> or more, to anchor for example in the aortic root and/or the sinotubular junction), a relatively smaller diameter in an middle portion (e.g., about <NUM> or less, to position for example in the ascending aorta without exerting additional radial force on the fragile aortic wall where a dissection has occurred), and a relatively larger diameter at its proximal end (e.g., about <NUM> or more, to anchor for example in the descending aorta). In other embodiments it may have a relatively smaller diameter in its proximal region (e.g., <NUM> or less) to conform to a smaller descending aorta diameter and a relatively larger diameter in the middle portion if the ascending aorta diameter is much larger and dilated (e.g., <NUM>).

It is understood that any specific order or hierarchy of blocks in the processes disclosed is an illustration of example approaches. Based upon implementation preferences, it is understood that the specific order or hierarchy of blocks in the processes may be rearranged, or that not all illustrated blocks be performed. Any of the blocks may be performed simultaneously. In one or more embodiments, multitasking and parallel processing may be advantageous.

The subject technology is illustrated, for example, according to various aspects described above.

As used herein, the phrase "at least one of' preceding a series of items, with the term "or" to separate any of the items, modifies the list as a whole, rather than each item of the list.

It is understood that some or all steps, operations, or processes may be performed automatically, without the intervention of a user. Method claims may be provided to present elements of the various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

Claim 1:
An aortic dissection system (<NUM>) for treating a dissection within an aorta of a patient, the aortic dissection system comprising:
an aortic dissection implant (<NUM>) comprising:
an expandable support structure (<NUM>) having a proximal end (<NUM>) and a distal end (<NUM>), wherein the expandable support structure is configured to extend from the descending aorta, through the aortic arch and into the ascending aorta; and
at least one layer (<NUM>) provided over the expandable support structure comprising an atraumatic outer surface configured to engage an inner wall of the aorta adjacent a false lumen (<NUM>) associated with the dissection (<NUM>); and
an expandable interface structure (<NUM>) configured to expand within the aortic root, the expandable interface structure comprising a trilobe shape configured to anchor the expandable interface structure in the aortic root; and
a delivery system (<NUM>) configured to be inserted percutaneously into the patient and advanced into the patient's aorta, the delivery system comprising an outer sheath (<NUM>) configured to receive the aortic dissection implant therein in a compressed configuration.