Patent Description:
The present disclosure relates generally to medical devices that are used in the human body. In particular, the present disclosure is directed to embodiments of an occlusion device that enables material apposition against tissue walls surrounding a vascular abnormality and facilitates a smooth transition between the tissue and the device. More specifically, the present disclosure is directed to an occlusion device with a disc having an increased depth, giving the disc a more three-dimensional cross-section. The embodiments and methods disclosed herein enable improved blood flow along or proximate to the disc after the occlusion device has been placed within the target site.

An occluder is a medical device used to treat (e.g., occlude) tissue at a target site within the human body, such as an abnormality, a vessel, an organ, an opening, a chamber, a channel, a hole, a cavity, a lumen, or the like. For example, an occluder may be used in Left Atrial Appendage (LAA) closures. LAAs are common heart defects in which there is a sac in the muscle wall of the left atrium. When a patient experiences atrial fibrillation (AFib), a blood clot may be formed in the LAA which may become dislodged and enter the blood stream. By occluding the LAA, the release of blood clots from the LAA may be significantly reduced, if not eliminated. Various techniques have been developed to occlude the LAA. For instance, balloon-like devices have been developed that are configured to be implanted completely within the cavity of the LAA, while surgical techniques have also been developed where the cavity of the LAA is inverted and surgically closed.

In the case of some known medical devices, a lobed portion of the device sits in a body of the LAA, and a disc portion is engaged with the opening of the LAA. The disc of these known devices is generally a two-dimensional shape, formed from two directly adjacent layers of metal fabric. With the diverse anatomy of LAAs, the implantation of a medical device designed to occlude the LAA may not result in optimal implantation, and the two-dimensional disc of the above described medical devices may potentially slip at least partially into the opening of the LAA, which may lead to areas of stagnant blood flow within the patient's vascular system. The presence of stagnant blood flow may increase the risk of a patient developing device related thrombosis (DRT), which may lead to further medical complications.

It would be advantageous to provide an improved occlusion device that reduces the risk of DRT by minimizing stagnant blood flow proximate to the deployed medical device. <CIT> relates to an occluder for a left atrial appendage comprising a proximal portion comprising a braiding of at least one thread being radially self-expandable in a radial direction, to an expanded state, substantially perpendicular to a surface of inner walls of the left atrial appendage, whereby said braiding is engageable with said inner walls of a proximal end of said left atrial appendage, whereby in said expanded state, said proximal portion has a defined stiffness and resilience to be deformable by, and conformable to, said inner walls, whereby said braiding is configured to form a sealing connection, upon expansion in said radial direction, with said inner walls along a sealing portion of said braiding extending in a longitudinal direction of said occluder, substantially perpendicular to said radial direction. Said occluder comprising further a distal anchoring portion comprising an anchoring wire being radially expandable from a reduced diameter shape to an expanded diameter shape, said anchoring portion having a higher defined stiffness than said proximal portion, and a flexing element connecting said anchoring portion and said proximal portion. <CIT> relates to a left atrial appendage implant with sealing balloon. <CIT> relates to a transcatheter left atrial appendage plugging system. <CIT> discloses medical devices for treating certain vascular abnormalities. <CIT> relates to devices and methods for treating various target sites, such as vascular abnormalities. An example medical device includes at least one layer of a fabric of braided strands having proximal and distal ends and a central axis extending therebetween. <CIT> relates to a left atrial appendage occluder.

The present disclosure generally relates to medical devices and methods of use thereof, including a disc with increased depth, giving the disc a more three-dimensional cross section which facilitates improved blood flow along or proximate to the disc after the occlusion device has been placed within the target site.

The invention is defined by the independent claim. Embodiments of the invention are defined by the dependent claims. The methods disclosed in the present disclosure are not part of the invention but are useful for illustrative purposes.

In one embodiment, the present disclosure is directed to a medical device for treating a target site. The medical device includes a proximal end and a distal end. The proximal end includes a disc and the distal end includes a lobe. The disc and the lobe are connected by a connecting member. The disc includes a proximal surface, a distal surface, and a central surface. The central surface extends between and connects the proximal surface and the distal surface. The central surface separates the proximal surface from the distal surface by a predetermined depth distance.

In another embodiment, a delivery system for deploying a medical device to a target site is provided. The delivery system includes a medical device and a delivery device. The medical device includes a proximal end and a distal end. The proximal end includes a disc and the distal end includes a lobe. The disc and the lobe are connected by a connecting member. The disc includes a proximal surface, a distal surface, and a central surface. The central surface extends between and connects the proximal surface and the distal surface. The central surface separates the proximal surface from the distal surface by a predetermined depth distance. The delivery device includes a delivery catheter, a delivery cable within the delivery catheter and translatable with respect to the delivery catheter, and a coupling member configured to couple the medical device to the delivery cable for facilitating at least one of deployment of the medical device at the target site and subsequent removal of the frame from the medical device.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. It is understood that that Figures are not necessarily to scale.

The present disclosure relates generally to medical devices that are used in the human body. Specifically, the present disclosure provides medical devices, such as occlusion devices, including a distal lobe and a proximal disc, in which the disc has a defined depth, or a more three-dimensional shape than two-dimensional discs of at least some known medical devices.

Accordingly, the occlusion devices of the present disclosure facilitate improved and more uniform apposition of the disc against the tissue surrounding the vascular abnormality, which enables a smooth transition between the surrounding tissue and the medical device. Therefore, stagnant blood flow around the medical device or the abnormality may be reduced or eliminated.

The disclosed embodiments may lead to more consistent and improved patient outcomes. It is contemplated, however, that the described features and methods of the present disclosure as described herein may be incorporated into any number of systems as would be appreciated by one of ordinary skill in the art based on the disclosure herein.

Although the exemplary embodiment of the medical device is described as treating a target site including a left atrial appendage (LAA), it is understood that the use of the term "target site" is not meant to be limiting, as the medical device may be configured to treat any target site, such as an abnormality, a vessel, an organ, an opening, a chamber, a channel, a hole, a cavity, or the like, located anywhere in the body. The term "vascular abnormality," as used herein is not meant to be limiting, as the medical device may be configured to bridge or otherwise support a variety of vascular abnormalities. For example, the vascular abnormality could be any abnormality that affects the shape of the native lumen, such as an atrial septal defect, an LAA, a lesion, a vessel dissection, or a tumor. Embodiments of the medical device may be useful, for example, for occluding an LAA, patent foreman ovalis (PFO), atrial septal defect (ASD), ventricular septal defect (VSD), or patent ductus arteriosus (PDA), as noted above. Furthermore, the term "lumen" is also not meant to be limiting, as the vascular abnormality may reside in a variety of locations within the vasculature, such as a vessel, an artery, a vein, a passageway, an organ, a cavity, or the like. As used herein, the term "proximal" refers to a part of the medical device or the delivery device that is closest to the operator, and the term "distal" refers to a part of the medical device or the delivery device that is farther from the operator at any given time as the medical device is being delivered through the delivery device. In addition, the terms "deployed" and "implanted" may be used interchangeably herein.

Some embodiments of the present disclosure provide an improved percutaneous catheter directed intravascular occlusion device for use in the vasculature in patients' bodies, such as blood vessels, channels, lumens, a hole through tissue, cavities, and the like, such as a left atrial appendage. Other physiologic conditions in the body occur where it is also desirous to occlude a vessel or other passageway to prevent blood flow into or therethrough. These device embodiments may be used anywhere in the vasculature where the anatomical conditions are appropriate for the design.

The medical device may include one or more layers of occlusive material, wherein each layer may be comprised of any material that is configured to substantially preclude or occlude the flow of blood so as to facilitate thrombosis. As used herein, "substantially preclude or occlude flow" shall mean, functionally, that blood flow may occur for a short time, but that the body's clotting mechanism or protein or other body deposits on the occlusive material results in occlusion or flow stoppage after this initial period.

The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosure are shown. Indeed, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

As shown in <FIG>, at least some conventional or known medical devices <NUM> used for the occlusion of abnormalities include a disc <NUM> at a proximal end <NUM> and a lobe <NUM> at a distal end <NUM> thereof. Disc <NUM> is formed from an occlusive material that extends in a flat (e.g., two-dimensional) and planar configuration from a center of medical device <NUM> to a peripheral edge <NUM>.

When known medical device <NUM> is deployed at a target site <NUM> (e.g., a left atrial appendage (LAA)), lobe <NUM> is positioned within the body of the LAA <NUM> and provides a layer of occlusion. Disc <NUM> is intended to abut the tissue at an opening <NUM> of the LAA and provides another layer of occlusion. Additionally, disc <NUM> prevents lobe <NUM> from shifting within the body of the LAA <NUM>. When disc <NUM> has a two-dimensional configuration, disc <NUM> may recede at least partially into the body of the LAA <NUM>, which may lead to areas <NUM> of stagnant flow in the region between opening <NUM> and the retracted edge <NUM> of disc <NUM>, thereby increasing the risk of the patient developing DRT.

The medical devices of the present disclosure include a disc having a more three-dimensional shape, providing more depth and allowing for greater material apposition against the tissue at the opening to the abnormality while allowing for a smooth transition between the surrounding tissue and the medical device. The medical devices of the present disclosure thereby minimize the above-described disadvantages of known medical devices.

Turning now to <FIG>, a schematic diagram of a delivery system <NUM> is shown. Delivery system <NUM> includes a delivery device <NUM> including a catheter <NUM> and a coupling member <NUM> configured to couple a distal end of a delivery cable <NUM> to a medical device <NUM> for facilitating the deployment of medical device <NUM> at a target site. Medical device <NUM> is deployed to treat the target site, and, in the example embodiment, is an occlusion device ("occluder").

Turning now to <FIG>, a schematic diagram of blood flow when medical device <NUM> according to the present disclosure is utilized for the occlusion of a target site <NUM> (e.g., an LAA) is shown. Medical device <NUM> includes a proximal end <NUM> and a distal end <NUM>, wherein proximal end <NUM> includes a disc <NUM> and distal end <NUM> includes a lobe <NUM>. Disc <NUM> is connected to lobe <NUM> by a connecting segment <NUM>. When device <NUM> is deployed at the LAA <NUM>, lobe <NUM> is positioned within the body of the LAA <NUM> and disc <NUM> is positioned at an opening <NUM> of the LAA <NUM>. In the exemplary embodiment, disc <NUM> is formed with a three-dimensional shape, or having an appreciable depth, as described further herein, allowing for greater material apposition of disc <NUM> against tissue or walls <NUM> of the atrium around the opening <NUM> to the LAA <NUM>, while maintaining a smooth transition between the walls <NUM> of the heart and disc <NUM>. This increased material apposition decreases the risk of stagnant blood flow and ensures normal blood flow in a flow direction <NUM> proximate to disc <NUM> (e.g., along a proximal surface <NUM> thereof).

<FIG> illustrate respective exemplary embodiments of disc <NUM> of medical device <NUM>. In these embodiments, an entirety of disc <NUM> is three-dimensional in shape or has an appreciable depth. Specifically, <FIG> is a cross sectional view of disc <NUM> formed with a rectangular three-dimensional shape, <FIG> is a cross sectional view of disc <NUM> formed with a half-rounded (or partially rounded) three-dimensional shape, <FIG> is a cross sectional view of disc <NUM> formed with a fully rounded shape, and <FIG> is a cross sectional view of disc <NUM> formed with a trapezoidal three-dimensional shape.

As shown in <FIG>, disc <NUM> includes a proximal surface <NUM> having a first length (or diameter) L<NUM>, a distal surface <NUM> having a second length (or diameter) L<NUM>, and a central surface <NUM> (also referred to as an edge surface or edge). Central surface <NUM> extends between and connects proximal surface <NUM> and distal surface <NUM>. A depth D of disc <NUM> is defined between proximal surface <NUM> and distal surface <NUM>. In some embodiments, a length of central surface <NUM> corresponds to or defines depth D. In some embodiments, such as the embodiment of disc <NUM> shown in <FIG>, depth D is defined consistently along the entirety of disc <NUM>. In other embodiments, depth D varies along disc <NUM>. Depth D may be <NUM> to <NUM> inches (<NUM> to <NUM>), more particularly <NUM> to <NUM> inches (<NUM> to <NUM>).

Proximal surface <NUM>, distal surface <NUM>, and central surface <NUM> define a cavity <NUM> of disc <NUM> therebetween. In the exemplary embodiment, disc <NUM> (and the rest of medical device <NUM>) is formed from an occlusive fabric <NUM>, and cavity <NUM> is defined between sheets of fabric <NUM> forming proximal surface <NUM> and distal surface <NUM> (which may be each be defined by a single layer or a double layer of fabric <NUM>). That is, depth D represents a depth distance defined between these surfaces <NUM>, <NUM> and by which surface <NUM>, <NUM> are separated.

As shown in <FIG> and <FIG>, first length L<NUM> (or diameter) of proximal surface <NUM> may be approximately equal to second length L<NUM> (or diameter) of distal surface <NUM>. As shown in <FIG> and <FIG>, first length L<NUM> of proximal surface <NUM> may be greater than second length L<NUM> of distal surface <NUM>.

In some embodiments, central surface <NUM> extends linearly between proximal surface <NUM> and distal surface <NUM> (see, e.g., <FIG> and <FIG>). Central surface <NUM> may adjoin proximal surface <NUM> at an angle A<NUM>. Angle A<NUM> may be approximately equal to a <NUM> degree angle or may be less than <NUM> degrees. Central surface <NUM> may adj oin distal surface <NUM> at an angle A<NUM>. Angle A<NUM> may be greater than or equal to about <NUM> degrees.

Central surface <NUM> may alternatively adjoin proximal surface <NUM> and/or distal surface <NUM> with an angular or arcuate (e.g., curved) connection (see, e.g., <FIG> and <FIG>). It is also contemplated that central surface <NUM> may be curved between proximal surface <NUM> and distal surface <NUM> (see, e.g., <FIG> and <FIG>). Central surface <NUM> may have a radius of curvature. The radius of curvature may be in a range between <NUM> to <NUM> inches (<NUM> to <NUM>), more particularly <NUM> to <NUM> inches or <NUM> to <NUM>. The radius of curvature may vary to ensure proper occlusive function and/or positioning of disc <NUM> within opening <NUM>, while maintaining normal blood flow along or proximate to disc <NUM>.

<FIG> illustrates another embodiment of disc <NUM> of medical device <NUM>, in which portions of disc <NUM> are three-dimensional. Proximal surface <NUM> includes a proximal peripheral portion <NUM>. Distal surface <NUM> includes a distal peripheral portion <NUM>. Central surface <NUM> extends between and connects proximal peripheral portion <NUM> and distal peripheral portion <NUM>. In some embodiments, proximal peripheral portion <NUM> and/or distal peripheral portion <NUM> extends in a proximal longitudinal direction.

In the embodiment of <FIG>, cavity <NUM> is defined along the periphery of disc <NUM>, as an annular cavity <NUM>. That is, proximal surface <NUM> and distal surface <NUM> are spaced apart only along the periphery of disc <NUM>. The depth distance D, defined between proximal surface <NUM> and distal surface <NUM> at peripheral portions <NUM>, <NUM> thereof, provides a three-dimensional shape to the peripheral edges of disc <NUM>. A central portion <NUM> of proximal surface <NUM>, radially inward of peripheral portion <NUM>, is directly adjacent to a central portion <NUM> of distal surface <NUM>, radially inward of peripheral portion <NUM> (e.g., no cavity <NUM> is defined between surfaces <NUM>, <NUM> in this central portion).

In one embodiment, medical device <NUM> is formed from a shape-memory material. One particular shape memory material that may be used is Nitinol. Nitinol alloys are highly elastic and are said to be "superelastic," or "pseudoelastic. " This elasticity may allow medical device <NUM> to be resilient and return to a preset, expanded configuration for deployment following passage in a distorted form through delivery catheter <NUM>. Further examples of materials and manufacturing methods for medical devices with shape memory properties are provided in <CIT>.

It is also understood that medical device may be formed from various materials other than Nitinol that have elastic properties, such as stainless steel, trade named alloys such as Elgiloy®, or Hastalloy, Phynox®, MP35N, CoCrMo alloys, metal, polymers, or a mixture of metal(s) and polymer(s). Suitable polymers may include PET (Dacron™), polyester, polypropylene, polyethylene, HDPE, Pebax, nylon, polyurethane, silicone, PTFE, polyolefins and ePTFE. Additionally, it is contemplated that the medical device may comprise any material that has the desired elastic properties to ensure that the device may be deployed, function as an occluder, and be recaptured in a manner disclosed within this application.

In some embodiments, disc <NUM> is shaped as desired by heat-setting fabric <NUM> over a mandrel having a complementary shape. Additionally or alternatively, disc <NUM> may include a frame therein, where the frame has the desired final shape of disc <NUM>. Fabric <NUM> may be coupled to this frame to form disc <NUM>.

Turning now to <FIG>, a flow diagram of an exemplary method <NUM> of using medical device <NUM> to occlude an LAA in a patient is shown. In the exemplary embodiment, method <NUM> includes providing <NUM> a medical device. As described herein, the medical device includes a proximal end and a distal end, wherein the proximal end comprises a disc and the distal end comprises a lobe, wherein the disc and lobe are connected by a connecting member, wherein the disc comprises a proximal surface, a distal surface, and a central surface extending between and connecting the proximal surface and distal surface, wherein the central surface separates the proximal surface from the distal surface by a predetermined depth distance.

Method <NUM> also includes advancing <NUM> the medical device to the LAA using a delivery system including a catheter and a delivery cable, positioning <NUM> the medical device relative to the LAA to occlude blood flow to and from the LAA, and de-coupling <NUM> the medical device from the delivery cable to deploy the medical device.

Method <NUM> may include additional, alternative, and/or fewer steps, including those described herein. For example, in some embodiments, positioning <NUM> the medical device relative to the LAA includes placing the lobe of the medical device within the body of the LAA and the disc outside of the LAA to abut the adjacent wall surrounding the opening of the LAA.

Additionally, de-coupling <NUM> the medical device from the delivery cable includes transitioning the medical device from the constricted configuration adopted for delivery from a catheter to the preset expanded configuration.

While embodiments of the present disclosure have been described, it should be understood that various changes, adaptations and modifications may be made therein without departing from the spirit of the disclosure and the scope of the appended claims. Further, all directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of the disclosure. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the disclosure as defined in the appended claims.

Claim 1:
A medical device (<NUM>) for treating a target site (<NUM>), wherein the target site is a left atrial appendage, the medical device comprises a proximal end (<NUM>), a distal end (<NUM>) and a connecting member (<NUM>),
wherein the proximal end comprises a disc (<NUM>) and the distal end comprises a lobe (<NUM>),
wherein the disc (<NUM>) and lobe are spaced from one another and connected by the connecting member (<NUM>),
wherein the disc comprises a proximal surface (<NUM>), a distal surface (<NUM>), and a central surface (<NUM>) extending between and connecting the proximal surface and distal surface,
wherein the central surface separates the proximal surface from the distal surface by a predetermined depth distance (D) such that an enclosed cavity (<NUM>) is defined between the proximal surface and the distal surface,
characterised in that the medical device is formed from an occlusive fabric and the predetermined depth distance is between <NUM> to <NUM> inches (<NUM> to <NUM>) and configured to increase material apposition against tissue at an opening of the target site while allowing for a smooth transition between the surrounding tissue and the medical device.