Heart occlusion devices

The disclosure is directed to a heart occlusion device and a method for occluding an aperture defect in a heart. The heart occlusion device includes two separate wires 12, 14. Each wire forms geometric shapes that together form a distal plate and a proximal plate. The first plate is disposed in a first plane. The second plate is disposed in a second plane that is parallel to and remote from the first plane. The distal plate and the proximal plate are separated by a self-centering waist. The proximal plate is attached to a hub. A similar hub is optional on the distal plate. The plates further include coverings which form a sealant to occlude an aperture in a tissue. The wires forming the plates have a shape-memory capability such that they can be collapsed and distorted in a catheter during delivery but resume and maintain their intended shape after delivery.

FIELD OF THE INVENTION

The present invention is directed to a medical device and particularly to a device for closing congenital cardiac defects. The present invention is specifically directed to a heart occlusion device with a self-centering mechanism.

DESCRIPTION OF THE PRIOR ART

A specific example of one such heart defect is a PFO. A PFO, illustrated inFIG. 1at6A, is a persistent, one-way, usually flap-like opening in the wall between the right atrium2and left atrium3of the heart1. Because left atrial (LA) pressure is normally higher than right atrial (RA) pressure, the flap usually stays closed. Under certain conditions, however, right atrial pressure can exceed left atrial pressure, creating the possibility that blood could pass from the right atrium2to the left atrium3, and blood clots could enter the systemic circulation. It is desirable that this circumstance be eliminated.

The foramen ovale6A serves a desired purpose when a fetus is gestating in utero. Because blood is oxygenated through the umbilical chord and not through the developing lungs, the circulatory system of the fetal heart allows the blood to flow through the foramen ovale as a physiologic conduit for right-to-left shunting. After birth, with the establishment of pulmonary circulation, the increased left atrial blood flow and pressure results in functional closure of the foramen ovale. This functional closure is subsequently followed by anatomical closure of the two over-lapping layers of tissue: septum primum8and septum secundum9. However, a PFO has been shown to persist in a number of adults.

The presence of a PFO defect is generally considered to have no therapeutic consequence in otherwise healthy adults. Paradoxical embolism via a PFO defect is considered in the diagnosis for patients who have suffered a stroke or transient ischemic attack (TIA) in the presence of a PFO and without another identified cause of ischemic stroke. While there is currently no definitive proof of a cause-effect relationship, many studies have confirmed a strong association between the presence of a PFO defect and the risk for paradoxical embolism or stroke. In addition, there is significant evidence that patients with a PFO defect who have had a cerebral vascular event are at increased risk for future, recurrent cerebrovascular events.

Accordingly, patients at such an increased risk are considered for prophylactic medical therapy to reduce the risk of a recurrent embolic event. These patients are commonly treated with oral anticoagulants, which potentially have adverse side effects, such as hemorrhaging, hematoma, and interactions with a variety of other drugs. The use of these drugs can alter a person's recovery and necessitate adjustments in a person's daily living pattern.

In certain cases, such as when anticoagulation is contraindicated, surgery may be necessary or desirable to close a PFO defect. The surgery would typically include suturing a PFO closed by attaching septum secundum to septum primum. This sutured attachment can be accomplished using either an interrupted or a continuous stitch and is a common way a surgeon shuts a PFO under direct visualization.

Umbrella devices and a variety of other similar mechanical closure devices, developed initially for percutaneous closure of atrial septal defects (ASDs), have been used in some instances to close PFOB. These devices potentially allow patients to avoid the side effects often associated with anticoagulation therapies and the risks of invasive surgery. However, umbrella devices and the like that are designed for ASDs are not optimally suited for use as PFO closure devices.

Currently available septal closure devices present drawbacks, including technically complex implantation procedures. Additionally, there are not insignificant complications due to thrombus, fractures of the components, conduction system disturbances, perforations of heart tissue, and residual leaks. Many devices have high septal profile and include large masses of foreign material, which may lead to unfavorable body adaptation of a device. Given that ASD devices are designed to occlude holes, many lack anatomic conformability to the flap-like anatomy of PFOB. The flap-like opening of the PFO is complex, and devices with a central post or devices that are self-centering may not close the defect completely, an outcome that is highly desired when closing a PFO defect. Hence, a device with a waist which can conform to the defect will have much higher chance of completely closing the defect. Even if an occlusive seal is formed, the device may be deployed in the heart on an angle, leaving some components insecurely seated against the septum and, thereby, risking thrombus formation due to hemodynamic disturbances. Finally, some septal closure devices are complex to manufacture, which may result in inconsistent product performance.

Devices for occluding other heart defects, e.g., ASD, VSD, PDA, also have drawbacks. For example, currently available devices tend to be either self-centering or non-self-centering and may not properly conform to the intra-cardiac anatomy. Both of these characteristics have distinct advantages and disadvantages. The non-self centering device may not close the defect completely and may need to be over-sized significantly. This type of device is usually not available for larger defects. Further, the self-centering device, if not sized properly, may cause injury to the heart.

Some have sharp edges, which may damage the heart causing potentially clinical problems.

Some devices contain too much nitinol/metal, which may cause untoward reaction in the patient and hence can be of concern for implanting physicians and patients.

Some currently marketed devices have numerous model numbers (several available sizes), making it difficult and uneconomical for hospitals and markets to invest in starting a congenital and structural heart interventional program.

The present invention is designed to address these and other deficiencies of prior art aperture closure devices. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this section.

SUMMARY OF THE INVENTION

The present invention is directed to a heart occlusion device with a self-centering mechanism comprising two separate, uniquely-shaped wires wherein each wire is shaped into two semi-circular designs to form two half-discs by the memory-shaping capability of the wires, a self-centering waist area formed between the two semi-circular designs, and a covering over the each of the two semi-circular designs, wherein the covering is a sealant from the heart occlusion.

More specifically, the present invention is directed to a device for occluding an aperture in tissue comprising a first flexible wire and a second flexible wire, wherein each of the first and second wires is comprised of a shape memory properties, and wherein each of the first and second wires is shaped into first and second generally semi-circular forms such that the first semicircular form of the first wire opposes the first semicircular form of the second wire to form a first disc and the second semicircular form of the first wire opposes the second semicircular form of the second wire to form a second disc wherein further each of the first and second discs is separated by a self-centering waist formed from two sections of the first wire and two sections of the second wire; and a sealed covering over each of the first and second discs, wherein the covering provides a seal to occlude the aperture.

The present invention is also directed to a device for occluding an aperture in a heart tissue comprising a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory property. Further, each of the first and second wires is shaped into first and second generally semi-circular forms such that the first semicircular form of the first wire opposes the first semicircular form of the second wire to form a first disc and the second semicircular form of the first wire opposes the second semicircular form of the second wire to form a second disc. Each of the first and second discs is separated by a self-centering waist formed from two sections of the first wire and two sections of the second wire, and wherein the two sections of the first wire and two sections of the second wire create an outward radial force to maintain the self-centering configuration of the device. Each of the first and second wires has a first and second end and wherein each of the first and second ends of the first and second wires is connected to a hub, wherein the hub further comprises a delivery attachment mechanism for attachment to a deployment cable. The device also includes a sealed covering over each of the first and second discs, wherein the covering provides a seal to occlude the aperture wherein the coverings comprise a flexible, biocompatible material capable of promoting tissue growth and/or act as a sealant.

The present invention is also directed to a method for inserting the occluder device described above into an aperture defect in a heart to prevent the flow of blood therethrough. The method comprises:a. attaching the occluder device to a removable deployment cable,b. placing the occluding device within a flexible delivery catheter having an open channel,c. feeding the catheter into a blood vessel and advancing the catheter via the blood vessel system to the aperture defect in the heart,d. advancing the catheter through the aperture defect,e. withdrawing the catheter from the occluder device such that the first disc of the occluder device expands on one side of the aperture defect,f. further withdrawing the catheter from the occluder device such that the second disc of the occluder device expands of the other side of the aperture defect, such that the waist of the occluder device expands by memory retention within the aperture defect to self-center the occluder device,g. further withdrawing the catheter from the blood vessel; andh. removing the deployment cable from the hub.

Advantages

The device of the present invention has many advantages:Lower Profile: The occluder device of the present invention has a lower profile than available devices.Conformable: The device is flexible and conformable to the patient anatomy, specifically the hole that is being closed. There are no sharp edges. The device is soft and hence less traumatic to the atrial tissue.Self-Centering on Demand: Because of the unique way the two discs are connected, the device has self-centering characteristics. The uniqueness of this device is in the self-centering mechanism. The waist of the device is made of four wires. The wires will have the capability to conform to the shape and size of the defect in the organ—a characteristic not seen in prior art devices. Therefore, the self-centering of the device is dependent upon the size and the shape of the defect. The wires will have enough radial force to maintain the self-centering configuration but will not be strong enough to press against the defect edges in a manner that exacerbates the defect. The device is fully repositionable and retrievable after deployment.Custom Fit: The device has the further ability to be custom-fit within the defect with balloon-expansion of the waist. Because of the self-expanding nature of the waist, this will not be needed in most cases. However, in cases in which custom expansion is needed (oval defects, tunnel defects), the waist size can be increased to conform to the defect by the balloon catheter expansion. A balloon may be inserted through a hollow screw attachment on the device's delivery hub and delivery cable. The expansion will be possible before the release of the device, which will increase the margin of safety.Fewer Sizes: The expandable waist requires fewer sizes to close a wider variety of differently-sized defects. Thus, a single device may offer physicians the ability to implant devices in several different sizes.The device will be less thrombogenic as the discs will be covered with ePTFE. The ePTFE has been time-tested and found to be least thrombogenic. There is the ability to close defects up to 42 mm with very mild modifications.Security: There will be the opportunity to remain tethered to the implanted device before releasing it, which is an extra security feature.
Uses:

The device of the present invention should be appropriate for an ASD (atrial septal defect), PFO (patent foramen ovale), VSD (ventricular septal defect), and PDA (patent ductus arteriosus) with minor modifications. One skilled in the art would also recognize the device's application for use as a vascular occluder or plug as well as an atrial appendage occluder.

An important use of the device will also be in closure of an aperture in a left atrial appendage. The device can be modified to conform to the atrial appendage anatomy. The discs are modified so that the device is not extruded out with the heartbeats. Yet, the device is still soft enough to form adequate closure.

The discs can also be modified so that they become compatible for closure of veins and arteries. For this use, the connecting waist will become equivalent (or near equivalent) to the diameter of the discs. Other important uses will be in closure of coronary artery fistulas, arteriovenous fistulas, arteriovenous malformations, etc.

The objects and advantages of the invention will appear more fully from the following detailed description of the preferred embodiment of the invention made in conjunction with the accompanying drawings.

In accordance with an exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane. The first plate has a center. The second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The waist is offset from the center of the first plate.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms around an inner region such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The waist comprises a first portion and a second portion. The first portion is connected to the inner region by a first segment. The second portion is connected to the inner region by a second segment. The first segment has a first length, and the second segment has a second length that is greater than the first length.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The first and second geometric forms comprise a first segment, a second segment, a third segment, and a fourth segment. The first segment is formed from a first of the two portions of the first wire. The first segment has a first length. The second segment is formed from a first of the two portions of the second wire. The second segment has a second length that is substantially equal to the first length. The third segment is formed from a second of the two portions of the first wire. The third segment generally opposes the first segment. The third segment has a third length that is greater than the first length. The fourth segment is formed from a second of the two portions of the second wire. The fourth segment generally opposes the first segment. The fourth segment has a fourth length that is substantially equal to the third length.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The first and second geometric forms comprise a first segment and a second segment. The first segment is formed from a first of the two portions of the first wire. The first segment has a first arm and a second arm. The first arm has a first length, and the second arm has a second length. The second length is greater than the first length. The second segment is formed from a first of the two portions of the second wire. The second segment has a third arm and a fourth arm. The third arm has the first length, and the fourth arm has the second length.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first plate has a first surface area. The second plate has a second surface area that is greater than the first surface area. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The waist has a length that is greater than eight millimeters.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to the first plane and greater than eight millimeters from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire, a second flexible wire, and a hook. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The hook is coupled to the first plate, and is configured for engagement with a positioning system.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms. The first geometric form of the first wire overlaps with the first geometric form of the second wire to form a first plate in a first plane. The second geometric form of the first wire overlaps with the second geometric form of the second wire to form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms separated by a waist formed from two portions of the first wire and two portions of the second wire. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane. The second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first plane has a first quadrant, a second quadrant that is adjacent to the first quadrant, a third quadrant that is below the first quadrant, and a fourth quadrant that is below the second quadrant and adjacent to the third quadrant. The first geometric form of the first wire extends through the first, second, and third quadrants of the first plane. The first geometric form of the second wire extends through the first, third, and fourth quadrants of the first plane.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The first plate and the second plate form a non-zero angle with respect to one another.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are not substantially parallel to one another and are separated by a waist formed from two portions of the first wire and two portions of the second wire.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from a first waist component of the first wire and a second waist component of the second wire, the first and second waist components being of unequal sizes.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from a first waist component of the first wire and a second waist component of the second wire. The first and second waist components are configured to generate a non-zero angle of curvature for the waist.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms between their respective first and second ends. The first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The first end of the first wire is disposed at a first hub. At least one of the second end of the first wire, the first end of the second wire, and the second end of the second wire is disposed at a second hub.

In accordance with another exemplary embodiment, a device for occluding an aperture in tissue is provided. The device comprises a first flexible wire, a second flexible wire, and a third flexible wire. Each of the first, second, and third wires is comprised of a shape memory material. Each of the first, second, and third wires is shaped into first and second geometric forms. The first geometric form of the first wire, the first geometric form of the second wire, and the first geometric form of the third wire form a first plate. The second geometric form of the first wire, the second geometric form of the second wire, and the second geometric form of the third wire form a second plate. The first and second plates are separated by a waist formed from two portions of the first wire, two portions of the second wire, and two portions of the third wire.

In accordance with another exemplary embodiment, a method for occluding an aperture defect in a heart to prevent the flow of blood therethrough is provided. The method comprises the steps of providing an occluder device comprising a first flexible wire and a second flexible wire. Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms around an inner region such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate in a first plane, and the second geometric form of the first wire and the second geometric form of the second wire form a second plate in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist formed from two portions of the first wire and two portions of the second wire. The occluder device further comprises a sealed covering over at least one of the first and second plates, wherein the covering provides a seal for the aperture defect. Each of the first and second wires has a first and second end. Each of the first and second ends of the first and second wires is connected to a hub. The hub further comprises a delivery attachment mechanism for attachment to a removable deployment cable. The method further comprises attaching the occluder device to the removable deployment cable, placing the occluder device within a flexible delivery catheter having an open channel, feeding the catheter into a blood vessel system and advancing the catheter via the blood vessel system to the aperture defect in the heart. The catheter is advanced through the aperture defect, and is withdrawn from the occluder device such that the first plate of the occluder device expands on a first side of the aperture defect. The catheter is further withdrawn from the occluder device such that the second plate of the occluder device expands on a second side of the aperture defect, such that the waist of the occluder device expands by memory retention within the aperture defect to self-center the occluder device. The catheter is further withdrawn from the blood vessel system, and the deployment cable is removed from the hub.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is merely exemplary in nature and is not intended to limit the disclosure or the application and uses of the disclosure. Furthermore, there is no intention to be bound by any theory presented in the preceding background information or the following detailed description.

The present invention provides a device for occluding an aperture within body tissue. One skilled in the art will recognize that the device and methods of the present invention may be used to treat other anatomical conditions in addition to those specifically discussed herein. As such, the invention should not be considered limited in applicability to any particular anatomical condition.

FIG. 1illustrates a human heart1, having a right atrium2, a left atrium3, a right ventricle4, and a left ventricle5. Shown are various anatomical anomalies6A,6B, and6C. The atrial septum7includes septum primum8and septum secundum9. The anatomy of the septum7varies widely within the population. In some people, the septum primum8extends to and overlaps with the septum secundum9. The septum primum8may be quite thin. When a PFO is present, blood could travel through the passage6A between septum primum8and septum secundum9(referred to as “the PFO tunnel”). Additionally or alternatively, the presence of an ASD could permit blood to travel through an aperture in the septal tissue, such as that schematically illustrated by aperture6B. A VSD is similar to an ASD, except that an aperture6C exists in the septum between the left and right ventricle of the heart.

PDA results from defects in the ductus arteriosus. The human blood circulation comprises a systemic circuit and a pulmonary circuit. In the embryonic phase of human development, the two circuits are joined to one another by the ductus arteriosus. The ductus connects the aorta (circulation to the body) to the pulmonary artery (pulmonary circuit). In normal development of an infant, this ductus closes after birth. If development is defective, it can happen that the ductus does not close, and as a result the two blood circuits are still joined even after birth.

Unless specifically described otherwise, “aperture”6will refer to the specific heart defects described above, including PFO6A, ASD6B, VSD6C, and PDA among others.

As used herein, “distal” refers to the direction away from a catheter insertion location and “proximal” refers to the direction nearer the insertion location.

As used herein, “memory” or “shape memory” refers to a property of materials to resume and maintain an intended shape despite being distorted for periods of time, such as during storage or during the process of delivery in vivo.

Referring now toFIGS. 2-5, the occluder device10of the present invention comprises two separate uniquely shaped memory wires12,14. The wire can be formed of biocompatible metals or polymers, such as bioresorbable polymers, shape memory polymers, shape memory metal alloys, biocompatible metals, bioresorbable metals, or combinations thereof. Specific examples include but are not limited to iron, magnesium, stainless steel, nitinol, or combinations of these and similar materials. A preferred metal for the present invention is a nitinol alloy. Nitinol (an acronym for Nickel Titanium Naval Ordnance Laboratory) is a family of intermetallic materials, which contain a nearly equal mixture of nickel (55 wt. %) and titanium. Other elements can be added to adjust or “tune” the material properties. Nitinol exhibits unique behavior, specifically, a well defined “shape memory” and super elasticity. In general, any biocompatible material with a memory capability can be used with the present invention. The thermal shape memory and/or superelastic properties of shape memory polymers and alloys permit the occluder10to resume and maintain its intended shape in vivo despite being distorted during the delivery process. In certain embodiments, the memory may also assist in pressing an aperture, such as a PFO tunnel, closed. The diameter or thickness of the wire depends on the size and type of the device, i.e., the larger the device, the larger the diameter of the wire. In general, wire having a diameter between about 0.2 mm and 0.8 mm can be used. As described further below in connection withFIGS. 12A,12B, and22, in certain embodiments more than two wires may be utilized.

The first wire12forms one or more first geometric forms12A and one or more second geometric forms12B. “Geometric forms” as used herein comprises symmetric as well as asymmetric forms. Relative to a delivery attachment mechanism or hub30, discussed below in greater detail, the first geometric form12A of the first wire12preferably comprises a distal geometric form, and the one or more second geometric forms12B of the first wire preferably each comprise proximal geometric forms. In the embodiment ofFIGS. 2-5, there is a single first, or distal, geometric form12A of the first wire12. Also in the embodiment ofFIGS. 2-5, there are two second, or proximal, geometric forms12B of the first wire12(namely,12B(A) and12B(B)). However, the number and configuration of the first and/or second geometric forms12A,12B of the first wire12may vary.

Similarly, the second wire14forms a first geometric form14A and a second geometric form14B. Relative to the hub30, the first geometric form14A of the second wire14preferably comprises a distal geometric form, and the second geometric form14B of the second wire preferably comprises a proximal geometric form. In the embodiment ofFIGS. 2-5, there is a single first, or distal, geometric form14A of the second wire14. Also in the embodiment ofFIGS. 2-5, there are two second, or proximal, geometric forms14B of the second wire14(namely,14B(A) and14B(B)). However, the number and configuration of the first and/or second geometric forms14A,14B of the second wire14may vary.

The first geometric forms12A of the first wire12and the first geometric forms14A of the second wire14form a first plate, such as a disc, or another otherwise relatively flat surface (hereinafter referred to as a “plate”)16in a first plane218. The second geometric forms12B of the first wire12and the second geometric forms14B of the second wire14form a second plate18(also referred to as a “disc” in certain embodiments) in a second plane220that is parallel to and remote from the first plane218. In the embodiment ofFIGS. 2-5, the first and second plates16,18each comprise one or more semi-circular discs (as described directly below). However, this may vary in other embodiments, for example as described further below in connection withFIGS. 21A-21E.

As shown inFIGS. 2-5, in these embodiments, each wire12or14forms a shape which mirrors that of the respective wire14or12. Specifically, each wire12,14forms a distal semi-circle or half-disc12A,14A in addition to two proximal quarter-circles or quarter-discs12B,12B′ or14B,14B′. The two proximal quarter-circles of each wire together form proximal semi-circles or half-discs12B,12B′ or14B,14B′. The two distal semi-circles of each respective wire12A,14A together comprise a distal circle or distal disc16of the occluder10. The four proximal quarter-circles12B,12W,14B,14W, which form a “four-leaf clover” configuration, comprise a proximal circle or proximal disc18of the occluder10.

The proximal semi-circle12B,12B′ or14B,14B′ of each wire is connected to the distal semi-circle12A or14A by waist portions (also referred to herein as waist components)12C,14C. As shown inFIG. 2, there are two waist portions12C,14C per wire. The four waist portions (two from each wire)12C,14C together comprise a restricted area or waist20of the occluder device10. The distance between the waist portions, both within the same wire and from wire to wire, determines the size of the waist20. The size of the waist20is dependent on the particular application and the size of the occluder device10. The resiliency and memory of the waist portions12C,14C and capacity to expand radially serves as a self-centering mechanism of the occluder device10in apertures6.

The Hub30:

The two half-discs are not attached or joined to each other except at the junction of the delivery attachment mechanism or hub30. The ends12D,14D of wires12,14will be welded or otherwise connected to the hub30.

According to some embodiments of the present invention, the distal disc16and/or proximal disc18may include membranous coverings24A and24B, illustrated inFIGS. 6 and 7. The membranous coverings24A and24B ensure more complete coverage of aperture6and promote encapsulation and endothelialization of tissue, thereby further encouraging anatomical closure of the tissue and improving closure rate. The coverings24A and24B also help stabilize the occluder device10.

The membranous coverings24A and24B may be formed of any flexible, biocompatible material capable of promoting tissue growth and/or act as a sealant, including but not limited to DACRON®, polyester fabrics, Teflon-based materials, ePTFE, polyurethanes, metallic materials, polyvinyl alcohol (PVA), extracellular matrix (ECM) or other bioengineered materials, synthetic bioabsorbable polymeric materials, other natural materials (e.g. collagen), or combinations of the foregoing materials. For example, the membranous coverings24A and24B may be formed of a thin metallic film or foil, e.g. a nitinol film or foil, as described in U.S. Pat. No. 7,335,426 (the entirety of which is incorporated herein by reference). The preferred material is Poly(tetrafluoroethene) (ePTFE), as it combines several important features such as thickness and the ability to stretch. Loops may also be stitched to the membranous coverings24A and24B to securely fasten the coverings to occluder10. The coverings may alternatively be glued, welded or otherwise attached to the occluder10via the wires12,14.

As illustrated inFIGS. 2-7, the diameters of the distal disc16and proximal disc18are generally 5-8 mm larger than the diameter of the connecting waist20. For example, if the diameter of the connecting waist20is 4 mm, the diameters of the discs16,18are generally about 9 mm each. Because of the flexibility in the waist20, a 12 mm waist device will be able to be placed in a 6 mm to 12 mm defect. For larger waists 20 or larger devices, the diameter of the disc size will increase proportionately.

It is within the scope of the present invention to envision occluder devices available in 7 or more sizes, specifically waist size having the following diameters for different-sized apertures6: 6 mm, 12 mm, 18 mm, 24 mm, 30 mm, 36 mm, and 42 mm.

In general, the occluder10may be inserted into an aperture6to prevent the flow of blood therethrough. As a non-limiting example, the occluder10may extend through a PFO6A or an ASD6B such that the distal disc16is located in the left atrium3and the proximal disc18is located in the right atrium2(as shown in the heart1inFIG. 1). The closure of apertures in these and other tissues, as well as other types of apertures, will become apparent as described below.

Referring now toFIGS. 8-10, the occluder device10is attached to a deployment cable34which is removably attached to the occluder device10at the hub30. As illustrated inFIG. 10, one method of releasably attaching the deployment cable34to the hub30is by threaded engagement utilizing a screw end36which engages unseen female threads within the hub30. Other known means of attachment can be used to releasably connect the deployment cable34to the hub30.

When the deployment cable34is engaged with the hub30, as illustrated inFIGS. 8 and 9, the occluder device10is initially housed within a flexible delivery catheter40having an open channel42. Reference is made toFIG. 8which illustrates the occluder device10in which the distal disc16is expanded, due to the memory expansion of the wires12and14, and housed within the open channel42of the delivery catheter40. During the initial stages of placement of the occluder device10, both the distal disc16and proximal disc18, as well as the coverings24A and24B, are housed within the open channel42of the delivery catheter40. In this manner, the catheter40is fed into the blood vessel through an already placed sheath and advanced via the blood vessel system to a defect in the heart.

Once the delivery catheter40traverses the aperture that needs to be occluded, e.g., a hole in the heart, the device10will be partially advanced from the catheter40as illustrated inFIG. 8. As the device10leaves the catheter40, the distal disc16, which includes the covering24A, begins to expand on the distal side of the aperture. Due to the memory capabilities of the wires12and14, the occluder device10begins to return to its normal shape such that the distal disc16expands on the distal side of the aperture in the heart. Once the distal disc16is completely out of the catheter opening42, as shown inFIG. 9, it16and the attached covering24A become fully expanded. The catheter40is further withdrawn to expose the waist20which then begins to emerge and expand due to the memory shape of the wires12and14. Advantageously, the waist20is designed to expand such that each of the wires forming the waist20are urged against the aperture in the heart causing a custom fit device of the occluder10within the aperture. As the catheter40is further withdrawn, the proximal disc18and the covering24B begin their process of expansion on the proximal side of the aperture. When the proximal disc18is fully delivered from the catheter40, it will expand and effectively form a seal over the aperture. The distal disc16and proximal disc18are secured in place by the action of the wires in the waist20urging against the aperture. At this stage, as shown inFIG. 10, the deployment cable34is removed from the hub30and the catheter40and the deployment cable34are removed from the body. The occluder device10is left in the heart at the region of the aperture. Over several months, skin tissue and other membranous structures will bind to the occluder device10thereby permanently locking the occluder device10to the specific area in the heart.

The two wires12,14function to form round discs16,18on each side of the tissue. The discs16,18maintain the circular shape because of the memory capability of the wires12,14. The coverings24A,24B will stabilize the discs and will act to completely occlude the defect.

The wires12,14at the waist portions12C,14C will be separated enough at the waist20to make the occluder device10self-centering. Due to the conformity of this design, the occluder device10should self-center within commonly (round, oval) shaped septal defects, as the waist20can adjust to any type of opening.

If a larger-diameter waist20is required, the waist20has the capability to expand (only if needed) to a larger size with the help of a balloon. In this manner, a center channel50extends through the deployment cable34, the hub30, and the screw end36. A balloon (not shown) is urged through the center channel50after the occluder device has been removed from the catheter40and expanded, and preferably before the hub30has been attached from the deployment cable34. The balloon is placed within the waist20and expanded. The waist20is dilatable, i.e., expandable, when gentle pressure of the balloon is applied. The dilation will expand the waist portions12C,14C. Once the desired diameter is reached, the balloon is deflated and removed by withdrawal through the center channel50. Once the occluder device10appears stable, the device10is separated from the deployment cable34as discussed above. In the majority of cases, balloon dilation will not be required.

In order to increase stability in the occluder device10and to avoid significant crimping of the waist20or the proximal or distal discs18,16, the waist20can be encircled by one or more restriction wires60,62as illustrated inFIG. 11. The restriction wires60,62can be made of the same wire material as the wires12and14, or they may be of a different material, such as plastic wire, fish line, etc. The restriction wires60,62may be welded or otherwise connected to the waist portions12C,14C. The purpose of the restriction wires60or62is also to restrict the circumference of the waist20if necessary. Although one restriction wire60is generally suitable, a second restriction wire62can also be incorporated to further improve stability.

Alternative Embodiments

Reference is now made toFIGS. 12-15for alternative embodiments of the occluder device10of the present invention. Unless otherwise noted, the same reference numbers will be applied to similar structures in each embodiment.

Reference is made toFIGS. 12A and 12Bfor an alternative embodiment of the occluder device (labeled as occluder device100inFIGS. 12A and 12B). The occluder device100in this embodiment is designed for PDA procedures. This embodiment is similar to previously described embodiments except that it is comprised of four wires112,114,116,118rather than two wires. In this case, each wire forms a mirror image of each of its neighboring wires. For example, wire112mirrors wire114as well as wire118, etc. Each of the four wires112,114,116,118forms a proximal quarter-disc112B,114B,116B,118B and a distal quarter-disc112A,114A,116A,118A. The proximal quarter-discs112B,114B,116B,118B together form a proximal disc111in a “four-leaf clover” configuration, and the distal quarter-discs112A,114A,116A,118A together form a distal disc110also in a “four-leaf clover” configuration. This embodiment also differs from previously-described embodiments in that the waist20is comprised of a single portion of each of the four wires112,114,116,118. This embodiment further differs from previously-described embodiments in that it comprises a second hub119with a screw mechanism. The second hub119connects to the distal disc110by distal ends112E,114E (116E,118E behind112E,114E inFIG. 12B) of each of the four wires112,114,116,118, just as proximal ends112D,114D (116D,118D behind112D,114D inFIG. 12B) connect to the proximal hub30. The wires112,114,116,118may be connected to the hubs30,119by welding or other means known in the art. The length of the waist20will be anywhere from 4-8 mm. In addition, the distal disc110is typically 4-8 mm larger than the waist20. However, the proximal disc111is generally 1-3 mm, preferably 2 mm, larger than the waist20diameter. Hence, the diameter of the distal disc110is larger than the diameter of the proximal disc111.

Reference is now made toFIG. 13for a second alternative embodiment of the occluder device120. This embodiment, like the embodiment shown inFIGS. 12A and 12B, uses four wires112,114,116,118and two hubs30,119. It is designed to close apertures in large arteries and veins. In occluder device120, the distal and proximal discs122and124are modified so that they are compatible with closure of veins and arteries. For this use, the connecting waist20is equivalent or near equivalent to the diameter of each of the discs122,124. The diameter of the waist20will be 1 mm smaller than the discs122,124. The length of the waist will be 4-8 mm. This embodiment can be used in the closure of coronary artery fistulas, arteriovenous fistulas, and arteriovenous malformations.

Reference is made toFIG. 14for a third alternative embodiment of the occluder device130. The importance of the occluder device130will be in the closure of the left atrial appendage. The device130is modified to conform to the atrial appendage anatomy. The distal disc132is modified so that the device130is not extruded out with the heartbeats. For the left atrial appendage occluder device130, the memory wire structure of the distal disc132is woven to form anywhere from 2 to 8 protuberances or hooks136. Upon inserting the device10in an aperture in the left atrial appendage of the heart, the hooks136grip the outer portion of the left atrium heart tissue and thereby assist in keeping the device130from extruding out of the left atrial appendage with contraction of the heart. The proximal disc134is typically flat and similar to the disc formed by the proximal discs18inFIGS. 2-7. The proximal disc134abuts the inner atrial wall of the heart. Typically, the waist20will be about 4-8 mm in diameter. The length of the waist may range from 4 to 16 mm.

Reference is made toFIG. 15for a fourth alternative embodiment of the occluder device140. Occluder device140is intended to occlude perimembranous ventricular septal (“PVS”) defects. This embodiment, like the embodiment shown inFIGS. 12A and 12B, uses four wires112,114,116,118and two hubs30,119. The occluder device140is different from other embodiments in that two of the four wires form truncated distal-quarter discs, with the effect that the distal disc142substantially misses half of the disc. Therefore, the device140has approximately 1.5 discs as opposed to two discs. The half distal disc142is also significantly longer than the proximal disc144. Typically, the distal disc142will be 6-8 mm in diameter. In addition, the distal disc142converges or curves inwards at143, i.e., it is angled to contact the ventricular septum when the device140is inserted in the PVS defect. (See below for details.) The lower edge of the proximal disc (opposite to the long distal disc) will be 3-4 mm larger than the waist, and the other half of the proximal disc will be 2-3 mm larger than the waist. The discs can also be modified to be of different shapes in the same device. Alternatively, the disc angle may be created by a straight distal disc142angled with respect to the plane perpendicular to the waist20in a slant fashion.

With reference toFIGS. 16-22, various additional exemplary alternative embodiments are provided with respect to the occluder device and/or components thereof. With reference toFIG. 16, certain embodiments of the occluder device10may have one or more plates16,18and/or geometric forms12A,12B,14A,14B of different sizes and/or configurations as compared with the embodiment described above in connection withFIG. 2. For example, the distal (or first) plate16and the proximal (or second) plate18may be offset with respect to the hub30, and/or one side of a plate16,18may be relatively higher or farther from the hub30than the other, for example via an oblique shift. In the particular embodiment ofFIG. 16, a center202of the hub30is not aligned with (and, rather, is offset against) a center204of the first plate16, but is aligned with a center206of the second plate18. In another embodiment, the distal plate16and the proximal plate18are of equal size, yet off set from each other via a shift in opposite directions from the hub.

In certain embodiments, the first and second plates16,18are configured such that a first segment formed from a first portion of the first wire12(for example, corresponding to form12B ofFIG. 16) has a first length, a second segment formed from a first portion of the second wire14(for example, corresponding to form14A ofFIG. 16) has a second length, a third segment formed for a second portion of the first wire12(for example, corresponding to form12A ofFIG. 16) has a third length, and a fourth segment formed for a second portion of the second wire14(for example, corresponding to form14B ofFIG. 16) has a fourth length. The second length is substantially equal to the first length. The third length is greater than the first length. The fourth length is substantially equal to the third length.

The semi-circle or half-disc12A of the first wire12(also referenced above as the first geometric form12A of the first wire12) may differ in size (for example, having a larger radius and therefore a larger surface area) from the semi-circle or half-disc14A of the second wire14(also referenced above as the first geometric form14A of the second wire14). In certain other embodiments, the semi-circle or half-disc12A of the first wire12and the semi-circle or half-disc14A of the second wire14may be of the same size same as one another, but may collectively form a distal plate16that differs in size from the proximal plate18. In one such embodiment, the distal plate16is smaller in surface area than the proximal plate18.

For example, the distal plate16may be of the same size as inFIG. 2, while the proximal plate18is larger in surface area than depicted inFIG. 2. This may occur, by way of example, when certain of the proximal quarter-circles of the second geometric forms12B,14B are larger in surface area than depicted inFIG. 2. Certain proximal quarter-circles of the second geometric forms12B,14B may be larger in surface area than other, adjacent quarter-circles of the second geometric forms12B,14B. Such differing sizes of the proximal quarter-circles of the second geometric forms12B,14B may be present regardless of the relative sizes of the distal and proximal plates16,18.

FIG. 17depicts an embodiment of an occluder device contemplated herein with a wider waist20. In one exemplary embodiment, the first plate16and the second plate18are disposed further apart as compared with the example ofFIG. 2, so that a total length225of the waist20is greater than eight millimeters. Preferably, in this embodiment, the length225of the waist20is greater than eight millimeters and less than or equal to ten millimeters. In one such example, a straight-line distance between the first plane218and the second plane220ofFIG. 2is greater than eight millimeters, and is preferably also less than or equal to ten millimeters.

FIG. 18depicts an embodiment of an occluder device contemplated herein with a hook engagement system230. The hook engagement system230comprises a hook232and a lanyard234coupled thereto. The hook232is connected to the first plate16or the second plate18(and to the first and/or second wires12,14thereof) described above, preferably proximate one of the coverings24A,24B. The hook engagement system230is configured for engagement with a positioning system (not depicted). In one embodiment, the hook engagement system230is used to remove the occluder device10from the heart. In this regard, a loop of the lanyard234is positioned onto the hook232, and the lanyard234is pulled in the direction away from the heart, thus pulling the occluder device10through the heart aperture and through the body. In another embodiment, the positioning system comprises a deployment system for deploying the occluder device10, for example by grasping the hook232for movement of the occluder device10into a human heart in a desired position proximate an aperture. In a further embodiment, the positioning system comprises a repositioning system for repositioning the occluder device10, for example by grasping the hook232for adjusting the position of the occluder device10for more ideal placement of the occluder device10proximate an aperture. In certain embodiments, the lanyard (and/or another connection feature) is part of the positioning system, and the hook may exist separately from the occluder device10. The hook232is preferably used in connection with a screw device for further engagement with the positioning system, such as a screw and nut system used in conjunction withFIGS. 8-10described above. For example, the hook232may be positioned internal to a screw and nut system during placement of the device. Alternatively, the hook232may be used in connection with a thread cord through an eyelet or an opening, so that the cord would need to be pulled in order to lose the connection with the occluder device10. In addition, such a cord may be used for retrieval of the occluder device10, for example by including multiple lumens, preferably with an opening or slit, as part of a catheter delivery system.

With reference toFIGS. 19 and 19A, an embodiment of an occluder device contemplated herein is depicted with overlapping wires at least at one plate. Overlapping wires add additional strength and rigidity to the plate of the occluder device. Specifically, the first geometric form12A of the first wire12overlaps at least a portion of one region (for example, at least a portion of a common spatial quadrant, half-plane, and/or quartile) in common with the first geometric form14A of the second wire14within the first plate16. Alternatively, or in addition, the second geometric form12B (not shown) of the first wire12overlaps at least a portion of one region (for example, at least a portion of a common spatial quadrant, half-plane, and/or quartile) in common with the second geometric form14B (not shown) of the second wire14within the second plate18(not shown).

In a preferred embodiment, as illustrated inFIG. 19, the first geometric form12A of the first wire12occupies at least three spatial quadrants300,301, and302, two of which (namely, spatial quadrants300and302) are shared in their entireties with the first geometric form14A of the second wire14. Likewise, the first geometric form14A of the second wire14occupies at least three spatial quadrants302,303, and300, two of which (namely, spatial quadrants300and302) are shared in their entireties with the first geometric form12A of the first wire12. Similarly, the second geometric form12B of the first wire12(not depicted inFIG. 19) occupies at least three spatial quadrants, two of which are shared in their entireties with the second geometric form14B of the second wire14(not depicted inFIG. 19). Likewise, the second geometric form14B of the second wire14occupies at least three spatial quadrants, two of which are shared in their entireties with the second geometric form12B of the first wire12.

FIG. 19Adepicts an exemplary classification of planar quadrants for the first and second planes218,220ofFIG. 2for reference with respect to the embodiment ofFIG. 19. One skilled in the art will recognize that less or more than four quadrants can be utilized. With reference toFIG. 19A, the first plane218ofFIG. 2has a first quadrant241(A), a second quadrant242(A) that is adjacent to the first quadrant241(A), a third quadrant243(A) that is below the first quadrant241(A), and a fourth quadrant244(A) that is below the second quadrant242(A) and adjacent to the third quadrant243(A). The second plane220ofFIG. 2has a first quadrant241(B), a second quadrant242(B) that is adjacent to the first quadrant241(B), a third quadrant243(B) that is below the first quadrant241(B), and a fourth quadrant244(B) that is below the second quadrant242(B) and adjacent to the third quadrant243(B). The first quadrant241(A) of the first plane218is closer to the first quadrant241(B) of the second plane220than to the second, third, or fourth quadrants242(B),243(B),244(B) of the second plane220. The second quadrant242(A) of the first plane218is closer to the second quadrant242(B) of the second plane220than to the first, third, or fourth quadrants241(B),243(B),244(B) of the second plane220. The third quadrant243(A) of the first plane218is closer to the third quadrant243(B) of the second plane220than to the first, second, or fourth quadrants241(B),242(B),244(B) of the second plane220. The fourth quadrant244(A) of the first plane218is closer to the fourth quadrant244(B) of the second plane220than to the first, second, or third quadrants241(B),242(B),243(B) of the second plane220.

With reference to the spatial quadrants set forth inFIG. 19A, in one preferred embodiment ofFIG. 19, the first geometric form12A of the first wire12extends through the first, second, and third quadrants241(A),242(A),243(A) of the first plane218. The first geometric form14A of the second wire14extends through the first, third, and fourth quadrants241(A),243(A), and244(A) of the first plane218. Accordingly, in this embodiment, the first geometric forms12A,14A of the first and second wires12,14share the first and third quadrants241(A),243(A) of the first plane218in common, for example to provide increased support and/or rigidity for the occluder device10.

Also in one version of this embodiment ofFIG. 19, the second geometric form12B of the first wire12extends through the first, second, and third quadrants241(B),242(B),243(B) of the second plane220. The second geometric form14B of the second wire14extends through the first, third, and fourth quadrants241(B),243(B),244(B) of the second plane220. Accordingly, in this version, the second geometric forms12A,14A of the first and second wires12,14share the first and third quadrants241(B),243(B) of the second plane220in common, for example to provide increased support and/or rigidity for the occluder device10.

However, this may vary in other versions or embodiments. For example, in another version of the embodiment depicted inFIG. 19, the second geometric form12B of the first wire12extends through the third, fourth, and first quadrants243(B),244(B),241(B) of the second plane220, and the second geometric form14B of the second wire14extends through the first, second, and third quadrants241(B),242(B),243(B) of the second plane220.

FIG. 20depicts an embodiment of an occluder device contemplated herein with a clothes-pin shape. In the embodiment ofFIG. 20, the first plate16and the second plate18described above are non-parallel, and form a non-zero angle260with respect to one another. The angle260is preferably greater than five degrees, is more preferably greater than ten degrees, and is most preferably approximately equal to twenty degrees.

Also in the embodiment ofFIG. 20, the waist20is configured such that the above-referenced waist components12C of the first wire12and the waist components14C of the second wire14are unequal in size. For example, as shown inFIG. 20, each waist component12C of the first wire12has a first length indicated by double arrow261, and each waist component14C of the second wire14has a second length indicated by double arrow262that is greater than the first length. The length is defined as the distance between the first plate16and the second plate18taken from a predetermined distance from the occluder device10's center point. Each waist component14C of the second wire14may also have a greater surface area and radius as compared to respective waist components12C of the first wire12. In addition, in the embodiment ofFIG. 20, the waist components12C of the first wire12and the waist components14C of the second wire14are preferably configured such that the waist20is curved, with a non-zero angle of curvature. The angle of curvature of the waist20is preferably greater than five degrees, is more preferably greater than ten degrees, and is most preferably greater than twenty degrees.

FIGS. 21A-21Edepict an embodiment of an occluder device contemplated herein in which one or more of the first and second plates16,18are non-circular in their geometric shape(s). In one embodiment ofFIG. 21A, at least the first plate16has a generally oval shape. In an embodiment ofFIG. 21B, at least the first plate16has a generally rectangular shape. In an embodiment ofFIG. 21C, at least the first plate16has a generally triangular shape. In an embodiment ofFIG. 21D, at least the first plate16has a generally elliptical shape. In an embodiment ofFIG. 21E, at least the first plate16has a generally keyhole shape. In certain versions, the first plate16and/or the second plate18have generally the same geometric shapes as one another. In certain other versions, the first plate16and/or the second plate18differ from one another. The first plate16and the second plate18may also comprise any number of other different geometric shapes.

FIG. 22depicts an embodiment of an occluder device contemplated herein that is formed by more than two wires. Specifically, in the embodiment ofFIG. 22, the occluder device10has three wires, namely: the first wire12and the second wire14described above, as well as a third wire205. In other embodiments, four wires may be utilized. In yet other embodiments, six wires may be utilized. In still other embodiments, the number of wires may differ further.

In the particular embodiment ofFIG. 22, the three wires12,14, and205each form respective, non-overlapping thirds of each plane. Specifically, as depicted inFIG. 22, the first geometric form12A of the first wire12is disposed within and extends through a first region272of the first plane218described above. The second geometric form12B of the second wire14is disposed within and extends through a second region274of the first plane218. A first geometric form207of the third wire205is disposed within and extends through a third region276of the first plane218. The first geometric forms12A,14A,207of the first, second, and third wires12,14,205collectively form the first plate16.

Within the first plane218, the first region272is adjacent to the second region274, with a common border277formed by the first and second wires12,14. The first region272is also adjacent to the third region276, with a common border278formed by the first and third wires12,205. In addition, the third region276is also adjacent to the second region274, with a common border279formed by the second and third wires14,205.

Similarly, the second geometric form12B of the first wire12, the second geometric form14B of the second wire14, and a second geometric form of the third wire205would likewise be disposed within and extend through three similar adjacent, non-overlapping regions of the second plane220, collectively forming the second plate18(not depicted inFIG. 22). The various first and second components of the first, second, and third wires12,14, and205are preferably curved with an arch, such as is shown inFIG. 22. Similar combinations of any number of different amounts of wires can similarly be used to form any number of different forms.

As mentioned above, in certain embodiments, the occluder device10may include multiple hubs30, for example as depicted inFIG. 15. The number and configuration of such multiple hubs30may vary in different embodiments. In one such embodiment, a first end of the first wire12is disposed at a first hub30, and at least one of the second end of the first wire12, the first end of the second wire14, and/or the second end of the second wire14is disposed at a second hub (such as hub119ofFIGS. 12B,13, and/or15). In one such exemplary embodiment, the first and second ends of the first wire12are disposed at the first hub30, and the first and second ends of the second wire14are disposed at the second hub (such as the second hub119ofFIG. 15). In another such exemplary embodiment, the first ends of the first and second wires12,14are disposed at the first hub30, and the second ends of the first and second wires12,14are disposed at the second hub (such as the hub119ofFIGS. 12B,13, and/or15), among other possible variations.

FIG. 23is a flowchart of an exemplary embodiment of a method2300for occluding an aperture defect in a heart. The method2300can be utilized in connection with the heart1ofFIG. 1and the various embodiments of the occluder device10ofFIGS. 2-22. Specifically, the method2300preferably utilizes one or more embodiments of the occluder devices10ofFIGS. 2-22to occlude an aperture defect of a heart, such as the aperture defect6A of the heart1depicted inFIG. 1.

As depicted inFIG. 23, the method2300includes the step of providing an occluder device (step2302). In various embodiments, the occluder device corresponds to the occluder device10depicted in any of the embodiments depicted inFIGS. 2-22and/or described above. The occluder device preferably comprises a first flexible wire (such as wire12described above) and a second flexible wire (such as wire14described above). Each of the first and second wires is comprised of a shape memory material. Each of the first and second wires is shaped into first and second geometric forms (such as forms12A,12B,14A, and14B described above) around an inner region such that the first geometric form of the first wire and the first geometric form of the second wire form a first plate (such as plate16described above) in a first plane, and the second geometric form12B of the first wire12and the second geometric form14B of the second wire14form a second plate (such as plate18described above) in a second plane that is parallel to and remote from the first plane. The first and second plates are separated by a waist (such as waist20described above) formed from two portions of the first wire and two portions of the second wire. A sealed covering (such as covering24A or24B described above) is preferably disposed over at least one of the first and second plates. The covering provides a seal for the aperture defect (such as the defect6A of the heart1described above). Each of the first and second wires has a first end and a second end. Each of the first and second ends of the first and second wires are connected to a hub (such as hub30described above). The hub further comprises a delivery attachment mechanism (for example, that includes or is used in connection with the catheter40described above) for attachment to a removable deployment cable (such as deployment cable34described above).

The method2300also includes the step of attaching the occluder device to the removable deployment cable (step2304). The occluder device is placed within a flexible delivery catheter (such as the catheter40described above) having an open channel (such as the channel42described above) (step2306). The catheter is fed into a blood vessel system (such as a blood vessel system of the heart1described above) and advanced via the blood vessel system to the aperture defect in the heart (step2308). The catheter, with the occluder device disposed within, is similarly advanced through the aperture defect (step2310).

In certain optional embodiments, a balloon sub-process2312is also utilized in occluding the aperture defect in the heart. In one such embodiment, depicted inFIG. 23, a balloon is advanced into the heart through the open channel toward the occluder device at the aperture defect (step2314). The balloon is also inserted into the waist of the occluder device (step2316). The balloon is then inflated (step2318), in order to help position the occluder device proximate the heart defect. Once the occluder device is properly positioned, the balloon is deflated (step2320) and then removed from the waist of the occluder device (step2322).

In other optional embodiments, a hook sub-process2324may be utilized in occluding the aperture defect in the heart. In one such embodiment, depicted inFIG. 23, a hook (such as one or more of the hooks136,232described above), is engaged with the delivery attachment mechanism (such as the catheter) (step2326), preferably via a screw system. The hook is manipulated using the delivery attachment mechanism and used to reposition the occluder device (step2328). In certain embodiments, the hook may also be utilized to retrieve the occluder device by exerting force on the delivery attachment mechanism in a direction away from the heart (step2330).

The catheter next is withdrawn from the occluder device (step2332). Preferably, the catheter is withdrawn from the occluder device in step2332in a manner such that the first plate of the occluder device expands on a first side of the aperture defect. In addition, the catheter is further withdrawn from the occluder device such that the second plate of the occluder device expands on a second side of the aperture defect (step2334). Preferably, the catheter is withdrawn from the occluder device in step2334in a manner, such that the waist of the occluder device expands by memory retention within the aperture defect to self-center the occluder device. The catheter is then withdrawn from the blood vessel system (step2336), and the deployment cable is removed from the hub of the occluder device (step2338).

It will be appreciated that certain steps of the method2300may vary in certain embodiments. It will also be appreciated that certain steps of the method2300may occur in a different order than is depicted inFIG. 23. For example, the optional hook sub-process2324may be used before the optional balloon sub-process2312. It will similarly be appreciated that certain steps of the method230may occur simultaneously with one another.

Other embodiments may comprise any combinations of the embodiments described herein and/or described in the drawings. It is understood that the disclosure is not confined to the particular construction and arrangement of parts herein illustrated and described, but embraces such modified forms thereof as come within the scope of the following claims. Additionally, it will be appreciated that various embodiments may be freely combined together, and/or that various features of different embodiments may be freely combined together.