Closure devices and tools

ES 2 297 563 T3

DESCRIPTION

Closing devices, and related delivery instruments.

This invention relates to devices for closing a passage in a body, for example a free passage foramen ovale in a heart, and to devices for delivering such closure devices.

Figure 20 shows a part of a heart in longitudinal section, in which the right atrium (RA), the left atrium (LA), the right ventricle (RV) and the left ventricle (LV) have been represented. Figure 20 also depicts the primary septum (SP), a fin-like structure, which normally covers the foramen ovale, an opening in the secondary septum (SS) of the heart. In the uterus, the foramen ovale serves as a physiologic conduit for right-to-left shunting of blood in the fetal heart. After birth, as pulmonary circulation is established, the increased pressure and blood flow to the left atrium presses the primary septum (SP) against the walls of the secondary septum (SS), covering the foramen ovale and resulting in a functional closure of the foramen ovale. This closure is usually followed by the anatomical closure of the foramen ovale, due to the fusion of the primary septum (SP) with the secondary septum (SS).

When anatomical closure of the foramen ovale does not occur, a free passage foramen ovale (PFO) is created. A free passage foramen ovale is a persistent opening, usually flap-like, between the primary atrial septum (SP) and the secondary septum (SS) of a heart. A free passage foramen ovale occurs when a partial fusion, or no fusion, of the primary septum (SP) with the secondary septum (SS) occurs. In the case of partial fusion, there is a persistent passage between the top of the primary septum (SP) and the secondary septum (SS). It is also possible that there may be more than one passage between the primary septum (SP) and the secondary septum (SS).

Studies have shown that a relatively large percentage of adults have a free passage foramen ovale (PFO). Embolism through a PSO is believed to be the cause of a significant number of ischemic strokes, particularly in relatively young patients. It has been estimated that in 50% of cryptogenic strokes, a PFO is present. Patients who suffer a cryptogenic stroke or transient ischemic attack (TIA) in the presence of a PFO are frequently considered for medical therapy in order to reduce the risk of a recurrent embolism event.

Drug therapy frequently includes oral anticoagulants, or antiplatelet agents. These therapies can have certain side effects, including bleeding. If drug therapy is not adequate, open heart surgery may be used to close a PFO with stitches, for example. Like other open surgical treatments, this surgery is very invasive, risky, requires general anesthesia, and can result in the recovery is long.

Nonsurgical closure of PFOs is possible with umbrella-like devices developed for percutaneous closure of atrial septal defects (ASDs) (a condition in which there is no primary septum (SP). Many of these commonly used devices are for ASDs, however, they are technically complex, bulky, and difficult to deploy in a precise place. In addition, such devices can be of recovery and / or modification of their difficult or impossible position, in case the initial positioning is not satisfactory. Furthermore, these devices are specially designed for ASDs, and therefore may not be suitable for closing and sealing a PFO, in particular because the primary septum (SP) overlaps the secondary septum (SS).

In EP 0362773 such a device for ASDs is described, comprising two foam discs joined by a loop of suture.

In accordance with the invention, tools and devices are provided for closing a passage in a body, and more particularly for closing a free passage foramen ovale (PFO).

According to another aspect of the invention, a device is provided for sealing a passage in a human body. The device comprises a first anchor adapted to be positioned near a first end of the passage, a second anchor to be positioned at a second end of the passage, and a flexible elongated member adapted to extend through the passage and connect the first and second anchors. , the elongated flexible member having a first end fixedly connected to the first anchor and a second end releasably connecting to the second anchor.

According to another aspect of the invention, a device for sealing a passageway in a human body comprises a first anchor adapted to be positioned close to a first end of the passage, a second anchor adapted to be positioned close to a second end of the passage, and a flexible elongated member adapted to extend through the passage and connect the first and second anchors, the elongated member being capable of moving through the second anchor to vary the length of the elongated member between the first and second anchors.

In accordance with another aspect of the invention, a device is provided for sealing a passageway in a heart. The device comprises a first anchor adapted to be positioned close to a first end of the passage, a second anchor adapted to be positioned close to a second end of the passage, and a flexible elongated member adapts

ES 2 297 563 T3 do to extend through the passageway and connect the first and second anchors, wherein the first anchor pivots relative to the elongated member and the second anchor pivots relative to the elongated member.

In accordance with yet another aspect of the invention, a device for sealing a passageway in a heart comprises a first anchor adapted to be positioned proximate a first end of the passage, a second anchor adapted to be positioned proximate a second end of the passage, and a flexible elongated member adapted to extend through the passageway and connect the first and second anchors, wherein each of the first and second anchors is collapsible, from an unfolded state to a folded delivery state.

In accordance with yet another aspect of the invention, there is provided a device for sealing a free passage foramen ovale in a heart. The device includes a first anchor that includes a first plurality of arms adapted to be positioned close to a first end of the free passage foramen ovale, a second anchor that includes a second plurality of arms adapted to be positioned close to a second end of the foramen free-flow oval, and a flexible elongated member adapted to extend through the free-flow foramen ovale and connect the first and second anchors, the elongated member having a first end fixedly connected to the first anchor and a second end releasably connecting to the second anchor, wherein each of the plurality of first and second arms are collapsible from an unfolded state to an unfolded state. delivery.

In accordance with another aspect of the invention, an assembly is provided for sealing a passageway in a heart. The assembly comprises a positioning catheter capable of extending into the passage, and a closure device capable of sealing the passage, the closure device including a first anchor adapted to be positioned near a first end of the passage, a second anchor adapted to be positioned proximal to a second end of the passage, and a flexible elongated member adapted to extend through the passage and connect the first and second anchors, wherein the closure device is capable of being positioned within the positioning catheter in a first folded state and is extensible from the positioning catheter in a second deployed state.

In accordance with yet another aspect of the invention, an assembly is provided for sealing a free passage foramen ovale in a heart. The assembly comprises a guiding catheter capable of extending to the free passage foramen ovale, a positioning catheter capable of extending through the guiding catheter to a position proximate the free passage foramen ovale, and a closure device capable of to seal the free passage foramen ovale, the closure device including a first anchor having a first plurality of arms adapted to be located close to a first end of the free passage foramen ovale, a second anchor having a second plurality of arms adapted to be located close to a second end of the free-passage foramen ovale, a flexible elongated member adapted to extend through the free-passage foramen ovale and connect the first and second anchors, and a releasable fixation mechanism that selectively engages a distal portion of the delivery catheter in position to releasably connect the second end of the elongated member to the second anchor, wherein the closure device is capable of being positioned within the delivery catheter at position in a first state, wherein each of the plurality of first and second arms are folded and extendable from the positioning catheter to a second deployed state, wherein each of the plurality of first and second arms is extended.

In accordance with another aspect of the invention, a closure device for sealing a passage in a heart comprises a left atrial anchor configured to close a first end of the passage, a right atrial anchor configured to close a second end of the passage, and an elongated member flexible connecting the left and right atrial anchors, wherein the elongated member has a first end fixedly connected to the left atrial anchor, and in that the right atrial anchor is movable relative to the elongated member and is configured to be releasably attached to the elongated member at any of a plurality of points along the length of the elongated member.

In accordance with another aspect of the invention, an assembly for sealing a passageway in a heart includes a guiding catheter configured to extend from a point of entry into a body to the passageway, and a closure device capable of sealing the passageway, including the closing device a first anchor adapted to be placed near a first end of the passage, a second anchor adapted to be placed near a second end of the passage, and a flexible elongated member connecting the first and second anchors, in which a first end of the elongated member is connected to the first anchor, and in which the elongated member extends through the second anchor and through the catheter to the point of entry into the body.

According to yet another aspect of the invention, a device for sealing a passage in a human body comprises a first anchor adapted to be positioned close to a first end of the passage, a second anchor adapted to be positioned close to a second end of the passage, and a flexible elongated member adapted to extend through the passage and connect the first and second anchors, the elongated member being capable of moving through the second anchor to vary the tension of the elongated member.

According to another aspect of the invention, a device for closing a passage in a human body comprises a first anchor adapted to be positioned close to a first end of the passage, a second anchor adapted to be positioned close to a second end of the passage, and a flexible elongated member adapted to extend through the passage and connect the first and second anchors, the elongated member having a first end releasably connected to the first anchor and a second end releasably connected to the second anchor.

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According to another aspect of the invention, a device for closing a passageway in a heart comprises a left atrial anchor adapted to be placed in the left atrium of a heart and including a plurality of bare arms, a right atrial anchor adapted to be placed in the right atrium of a heart and including a plurality of arms, and a cover attached to the plurality of arms, and a flexible elongated member adapted to extend through the passageway and connect the left and right atrial anchors, the elongated member having a first end fixedly connected to the left atrial anchor, and a second end releasably connected to the right atrial anchor.

According to another aspect of the invention, a device for sealing a passageway in a heart comprises a first anchor adapted to be positioned close to a first end of the passageway, the first anchor comprising a plurality of exposed arms, a second anchor adapted to be positioned close to a second end of the passage, the second anchor comprising a plurality of exposed arms, and a flexible elongated member adapted to extend through the passageway and connect the first and second anchors, the elongated member having a first end fixedly connected to the first anchor, and a second end releasably connecting to the second anchor.

Additional advantages of the invention will be set forth in part in the description that follows, and in part will become apparent in view of the description, or may become known by practice of the invention. The objects and advantages of the invention will be realized and achieved by means of the elements and combinations which are set forth particularly in the accompanying claims.

The general description made above, and the detailed description that follows are only examples and explanatory descriptions, not restrictive of the invention as it is claimed.

The accompanying drawings, which are incorporated in, and constitute a part of, this specification, illustrate various embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Figure 1 is a closure device located in a heart for closing a PFO, in accordance with one embodiment of the present invention.

Figure 2 is a delivery system guiding catheter inserted through a PFO and into the left atrium.

Figure 3 is a left atrial anchor of the closure device of Figure 1 being advanced out of the delivery guide catheter.

Figure 4 is a left atrial anchor of the closure device of Figure 1, advanced out of the delivery guide catheter.

Figure 5 is a left atrial anchor of Figure 4, which is being pulled towards the PFO.

Figure 6 is a guiding catheter being pulled proximately into the right atrium and the left atrial anchor seated against a septum wall.

Figure 7 is a right atrial anchor of the closure device of Figure 1, being extended from the delivery guide catheter.

Figure 8 is the right atrial anchor detached from the delivery guide catheter.

Figure 9 is the right atrial anchor advanced to contact the wall of the septum.

Figure 10 is the right atrial anchor attached to a tether of the closure device of Figure 1.

Figure 11 is a cross-sectional side view of a closure device, including a sectional view of a locking mechanism, in accordance with one embodiment of the present invention.

Figure 11A is a partial plan view of a left atrial anchor of the closure device of Figure 11, taken along line AA, in accordance with one embodiment of the present invention.

Figure 11B is a partial plan view of a right atrial anchor of the closure device of Figure 11, taken along line BB, shown without a cover, in accordance with one embodiment of the present invention.

Figure 11C is a partial plan view of the right atrial anchor of Figure 11B, shown with a cover, in accordance with one embodiment of the present invention.

ES 2 297 563 T3

Figure 12 is a cross-sectional side view of the closure device of Figure 11 with a positioning catheter (shown in cross-section) engaging a fixation mechanism (also shown in cross-section), in accordance with one embodiment of the present invention.

Figure 13 is a cross-sectional side view of the positioning catheter of Figure 12 as applied to another embodiment of a fixation mechanism in accordance with the present invention.

Figure 14 is a cross-sectional side view of a delivery system, including a guide catheter and a positioning catheter, in accordance with one embodiment of the present invention.

Figure 15 is a cross-sectional side view of a closure device and positioning catheter located in a guide or delivery catheter prior to deployment in a heart, in accordance with one embodiment of the present invention.

Figure 16 is a partial cross-sectional view of another embodiment of a fixation mechanism engaging a right atrial anchor, in accordance with the present invention.

Figure 17 is a cross-sectional side view of the closure device, positioning catheter, and guide or delivery catheter of Figure 15, with the closure device in a recovered position within the guide catheter, according to an embodiment of the present invention.

Figure 18 is a closure device of Figure 1 in a position covering a PFO where there is a relatively short overlap between the primary septum and the secondary septum, in accordance with one embodiment of the present invention.

Figure 19 is a closure device of Figure 1 in a position in which it covers a PFO after an access channel has been made to the left atrium, in accordance with one embodiment of the present invention.

Figure 20 is a longitudinal section of a part of a heart that has a PFO.

Figure 21 is a longitudinal cross section of a delivery system including a delivery sleeve containing a closure device in accordance with the present invention.

Reference will now be made in detail to embodiments of the invention, examples of which have been illustrated in the accompanying drawings. Wherever possible, the same reference numerals have been used throughout the drawings to refer to the same or similar parts.

The various Figures depict embodiments of free passage foramen ovale (PFO) closure devices, tools and devices for delivery of the PFO closure devices, and methods for using the device to close a PFO. The devices and associated methods are described here in relation to their use to seal a PFO. These devices, however, are also suitable for closing other openings or passageways, including other such openings in the heart, for example atrial septal defects, ventricular septal defects, and free-passage conduits of the arteries, and openings or passageways. in other parts of a body, such as an arteriovenous fistula. The invention is therefore not limited to the use of the closure devices of the invention to close the PFOs.

Figures 1 and 11 show a PFO closure device 10 in accordance with one embodiment of the present invention. In Figure 1, device 10 is shown positioned on either side of a PFO pathway (designated as PFO in the Figures) with a portion of device 10 passing through the PFO pathway after delivery from a delivery system. The PFO pathway can be seen more clearly in Figure 2, in which a catheter arranged in the PFO pathway between the primary septum (SP) and the secondary septum (SS) has been represented. As illustrated in Figure 1, the closure device 10 includes a left atrial anchor 12 located in the LA, a right atrial anchor 14 located in the RA, and a tie 16 that connects the anchoring structures.

As discussed and depicted herein in Figures 1 and 11, closure device 10 includes a left atrial anchor 12 connected to tether 16. Figure 11 depicts tether 16 extending through , and connects to, the right atrial anchor 14 via a releasable fixation mechanism 30 (which is secured to the right atrial anchor 14. When releasable fixation mechanism 30 is not secured, right atrial anchor 14 is movable along tether 16. As illustrated in Figure 11, releasable fixation mechanism 30 engages tether 16, which it extends through the right atrial anchor 14 on one side of the right anchor 14 that does not face the left anchor 12. Although it is preferable that the left atrial anchor 12 is permanently attached to the tether 16, it is possible that the left atrial tether 12 may also be attached to the tether 16 by a device similar to the releasable fixation mechanism 30.

In one embodiment, the tie 16 is formed of a multi-stranded braided polymeric material. Suitable materials include, but are not limited to, ultra high molecular weight polyethylene multifilament yarns (UHMWPE), such as SPECTRA or DYNEEMA. Other suitable materials include liquid crystal polymer (LCP), such as VECTRAM, polyester, or other high strength fibers. For the tie 16 other suitable materials of sufficient strength and flexibility may be used.

ES 2 297 563 T3

The releasable fastening mechanism 30 is preferably spring loaded as illustrated in Figure 11, in a condition of fastening on the tether 16, that is, the securing mechanism 30 secures the tether 16 to the anchor 14. The locking mechanism Releasable fixture 30 includes two piercing pins 32 directed in opposite directions, which are adapted to penetrate and pierce tie 16. Each piercing pin 32 includes a spring portion 32a that connects to a housing 31 and a corresponding piercing pin 32. In the illustrated embodiment, the housing 31 connects to an anchor link hub 36, which in turn connects to anchor 14, as will be described below.

Piercing pin 32 has a pointed end and is oriented generally orthogonal to tether 16. Spring portion 32a is connected to housing 31 in such a way that the natural, unloaded position of spring portion 32a forces a piercing pin 32 through tie 16. Piercing pins 32 have been illustrated as passing completely through tie 16, but it is contemplated that tenons 32 may only partially pass tie 16.

The piercing pins 32 cooperate with a piercing collar 34 that is attached to the housing 31. The collar 34 has an internal passage that is somewhat larger than the tie 16. In the illustrated embodiment, the collar 34 also has two passages, one for each piercing pin 32, through which the piercing pins 32 pass. Once piercing pins 32 have passed into (and potentially through) tether 16, piercing pins 32 securely lock tether 16 relative to releasable fixation mechanism 30 and consequently to right atrial anchor 14 The piercing collar 34 also holds the tie 16 in place if it is desired to remove the piercing pins 32 from the tie 16, as will be described later.

The piercing pins 32 are preferably formed of an elastic metal, with spring characteristics. Suitable materials include, but are not limited to, stainless steel, nickel titanium alloy, ELGILOY, or MP35N. Housing 31 is preferably a thin-walled tube formed from a biocompatible metal or polymer. The releasable attachment mechanism 30 illustrated in Figure 11 is an example only, and other embodiments of a releasable attachment mechanism suitable for attaching the tether 16 to the anchor 14 are contemplated, some of which will be described below.

Figure 12 illustrates the operation of the releasable fixation mechanism 30 depicted in Figure 11. In Figure 12, a right atrial anchor (RPC) positioning catheter 22 is engaged with the right atrial anchor 14, such that right atrial anchor 14 is not yet secured to tether 16. The RPC 22, as set forth herein and depicted in Figure 12, includes an inflatable balloon 24 which, when inflated, engages the releasable fixation mechanism 30, allowing the right atrial anchor 14 to be moved relative to the tether 16. The RPC 22 includes a lumen 26, which allows inflation and deflation of the balloon 24. A proximal end 24a of the balloon 24 is attached to a distal end of an outer tube 22b of the RPC 22, while a distal end 24b of the balloon 24 is attached to the distal end of an inner tube 22a of the RPC 22. The inner and outer tubes 22a, 22b of RPC 22 define lumen 26.

Balloon 24 is shown in Figure 12 in its inflated condition. Balloon 24 may be formed in the shape of a dumbbell, as illustrated, to facilitate engagement with releasable attachment mechanism 30. As illustrated, when balloon 24 is inflated, a distal portion of dumbbell-shaped balloon 24 presses against spring portions 32a, a proximal portion of balloon 24 expands without contacting any surface, and a waist portion The middle of the balloon 24 presses against the housing 31, limiting the expansion of that part of the waist. The distal portion of balloon 24 forces piercing pins 32 outward from tether 16. This is done by pressing the balloon 24 outward against the spring portions 32a of the piercing pins 32. Once a desired position for the right atrial anchor 14 has been established relative to the left atrial anchor 12 and the tether 16, a desired position is established for the right atrial anchor 14 with respect to the left atrial anchor 12 and the tether 16. deflates balloon 24, which allows piercing pins 32 to penetrate tie 16, locking anchor 14 relative to tie 16. If it is desired to modify the position of the right atrial anchor 14 after fixation, the RPC 22 is advanced along the tie 16 to reapply the releasable fixation mechanism 30. The balloon 34 is re-inflated, removing the pins 32 of the tie 16 and allowing to modify the position of the right atrial anchor 14 in relation to the tie 16.

The RPC 22 described and illustrated with respect to Figure 12 is an example only, and other catheter structures that may interact with a releasable fixation mechanism are contemplated. For example, catheter devices with alternative mechanical expansion structures can be used for releasably engagement with the fixation mechanism.

An embodiment of the left atrial anchor 12 and its connection to the tether 16 is illustrated in Figure 11A. As shown herein and illustrated in Figure 11A, the anchor 12 includes one or more arms 40, which are preferably extend through an anchor link hub 42. The junction socket 42 is tubular, preferably made of a biocompatible metallic material or a polymer, and includes radially oriented passageways, through which the arms 40 extend. One such radial passageway is shown in Figure 12, through which an arm 40 extends. Arms 40 may further be secured to hub 42 by suitable means, such as by welding, brazing, adhesive bonding, or by any other suitable method to secure arms 40 to hub 42. Attachment hub 42 The anchor also defines a longitudinal lumen 48, through which the tether 16 extends, as illustrated in Figure 11. Each arm 40 extends generally orthogonal through tie 16, passing through the braided structure of tie 16 and securing the

ES 2 297 563 T3 left atrial anchor to tether 16. Figure 11A illustrates anchor 12 having four arms, although any number of arms can be used, preferably from one to six. Although not shown in Figure 11, the arms 40 of this embodiment would be longitudinally spaced relative to each other, along the length of the tether 16, at least in the region of the anchor joint hub, i.e. , that two arms would not be located exactly at the same point in the tie 16.

Although the arms 40 preferably pass through the hub 42, in an alternative arrangement the arms 40 may not actually pass through the hub 42, that is, they may extend radially from the hub 42. Also, it is possible that instead of arms 40, the anchors 12,14 may comprise spiral structures, flat braided structures, or webs. Any structure of sufficient size and shape to keep the primary septum (SP) in contact with the secondary septum (SS) can be used to close the PFO.

The arms 40 are preferably made of metallic wire, such as stainless steel, nickel-titanium alloy, ELGILOY, or MP35N. In the case of nickel-titanium alloy, the wires can be used in either a superelastic mode, such that the wires unfold due to the superelastic properties of that alloy, or they can be used in a thermal transformation mode. In thermal transformation mode, the wires can be thoroughly cooled prior to deployment, for example by introducing thoroughly cooled saline into the delivery assembly, and then heated by exposure to blood, after removal of the wire. guiding catheter 20 (or a delivery sheath).

As illustrated in Figure 11A, the arms 40 can be straight. Alternatively, the arms 40 may be formed to have a concave shaped anchor to the wall of the atrium. The anchor 12 and its arms 40 will then be adapted to lie flat and seated on the surface of the wall of the atrium, once tensioned by the tie 16. It is preferable that the arms 40 are on, or close to, the surface of the atrial wall, once fully positioned, as this will facilitate tissue growth on the arms 40, and minimize thrombus formation and subsequent embolism of thrombi. To further help the arms 40 become rapidly endotheliolyzed and developed within the wall of the atrium, the arms 40 can be individually coated with a material to accelerate this development, such as with expanded PTFE, or with a woven polyester. loom. Arms 40, along with any desired coating, can further be coated with a non-thrombogenic material, such as heparin. All exposed surfaces of the closure device, including the entire length of the tie 16, can include such coatings.

To minimize frictional forces between a guide catheter 20 (or delivery sheath) and undeployed anchors, as well as to minimize trauma to tissues during deployment, the ends of the arms 40 are preferably rounded. (as can be seen in the representation of the right arm in Figure 11A). The ends of the arms 40 may also include small loops to receive sutures, for example, to suture a cover of the anchor 12. The total length of the arms (which will correspond to the diameter of the anchor) will depend on the particular anatomy to be treated, but preferably will vary between approximately 3-50 mm, for septum closure applications, including the closure of the PFO. The arms 40 need not extend an equal distance from the joint hub. Depending on the location of the PFO relative to the rest of the left atrium, it may be desirable for some of the arms 40 to extend asymmetrically from the junction hub 42, for example, being longer in the lower direction. Also, although Figure 11A shows the left atrial anchor 12 without a fabric covering the arm openings, it is envisaged that in some cases it may be beneficial to incorporate such a cover, similar to the one described below in relation to to the right atrial anchor 14 illustrated in Figure 11C.

An embodiment of the right atrial anchor 14 and its connection to the anchor attachment hub 36 is illustrated in Figure 11B. The tether 16 and the fabric covering the anchor 14 are not shown in Figure 11B. As set forth herein and depicted in Figure 11B, the right atrial anchor 14 includes one or more arms 50 that extend through the anchor attachment cradle 36. The junction hub 36 for the right atrial anchor 14 is similar to that for the left atrial anchor 12, and defines a longitudinal lumen 58 (see Figure 11), through which the tether 16 extends and passages 51 oriented radially through of which arms 50 extend. Unlike left atrial anchor 12, arms 50 do not extend through tether 16. Rather, arms 50 are formed to curve around tether 16 and follow the interior surface of anchor link hub 36, as illustrated in Figure 11B. Four arms are also illustrated in Figure 11B, but a greater or lesser number of arms can be used, preferably from one to six arms. The arms 50 may be formed straight (away from the hub 36), or in a concave shape, as described in connection with the left atrial anchor 12. Preferred materials include those described for the arms 40 of the left atrial anchorage. The total length of the arms 50 (which will correspond to the diameter of the anchor 14) will depend on the particular anatomy to be treated, but will preferably vary between about 3-50 mm for septum closure applications, including the closure of the PFO. In some cases, the arms 40 of the left atrial anchor are the same length as the arms 50 of the right atrial anchor, and in others they may be different, for example, shorter than the arms 50 of the right atrial anchor. This will depend on the anatomy of the heart.

The right atrial anchor 14 preferably includes a covering fabric or other membrane spanning the space between the arms 50. This covering, shown in Figure 11C at reference numeral 52, serves to ensure a hemodynamic seal of the PFO. Cover 52 is preferably formed from a single sheet, with a

ES 2 297 563 T3 hole to surround the connecting hub of the anchor 36, and is preferably located on the arms 50, in such a way that it faces the partition. Suitable materials for cover 52 include, but are not limited to, knitted or woven polyester fabric, or expanded PTFE. Preferably, cover 52 has a porosity that will promote rapid tissue growth. The shell 52 may further include a coating, for example of a non-thrombogenic material, such as heparin. The cover 52 may be attached to the arms 50 of the right atrial anchor 14 by suitable means, such as by suturing. As illustrated in Figure 11C, arm 50 may have a loop 54 formed at each of its ends, creating eyelets for a suture 56 to connect arm 50 to cover 52. Additional sutures may be incorporated along the length of the arms 50. Although not preferred and not discussed with respect to the left atrial anchor 12, it is possible to include a cover attached to the arms 40 of the left atrial anchor 12.

An alternate embodiment of a releasable locking mechanism is illustrated in Figure 13. A releasable fixation mechanism 60 cooperates with the RPC positioning catheter 22 of the right atrium, in a manner similar to that described above. As in the previous described embodiment, the anchor joint hub 36 connects to a housing 61 of the mechanism 60. Housing 61 contains a grip structure, preferably with two grips, a fixed grip 62a and a movable grip 62b. The fixed handle 62a is connected to the housing 61 and has a rough surface, with sharp projections like teeth. The movable handle 62b has a spring portion 62c connected to the housing 61. The handle 62b also includes sharp projections like teeth. When inflated, balloon 24 keeps movable handle 62b away from tie 16, but when balloon 24 is deflated, spring portion 62c forces movable handle 62b against tie 16, and also forces tie 16 against fixed handle 62a. In this way, the tether 16 connects in a fixed way with the right atrial anchor 14.

In another embodiment in accordance with the present invention, the closure device 10 does not necessarily have to incorporate a releasable locking mechanism, such as those described hereinabove. Rather, other structures can be used to secure right anchor 14 to tether 16. In such an embodiment, such as that illustrated in Figure 16, anchor 14 is connected to anchor attachment hub 36, as in the embodiments described above. Also, as in previous embodiments, once the right atrial anchor 14 is deployed, it is not yet attached to the tether 16. When the right atrial anchor 14 is in its desired position, a locking element 70 is advanced along tether 16, toward anchor 14. Element 70, when it reaches hub 36, will secure both tether 16 and anchor link hub 36. Locking element 70 is not necessarily releasable, and as such would be permanent. Block element 70 can be remotely moved by any suitable actuation mechanism known in the art, extending through a delivery assembly to its proximal end outside of the patient.

Locking member 70 is preferably tubular, and includes a series of projecting lugs 72. These lugs 72 can be oriented similarly to ratchet teeth (not shown), such that the locking element 70 can be remotely advanced along the tie 16, but resists proximal movement. . Alternatively, the locking element 70 can be positioned in the desired position in the tie 16, and upset to bite into the surface of the tie 16. As another alternative, the locking element 70 may have an outer surface 74 that has taper to engage with a taper inner surface 36a of the anchor joint hub 36, such as a wedge, as illustrated in Figure 16. As the locking element 70 is pushed into the anchor joint hub 36, the gripping surface 72 is forced inward to bite into the tie 16.

Although not shown, the locking element 70 could also be used in conjunction with the above-discussed embodiments that utilize a releasable locking mechanism. As such, the locking element 70 would provide additional security for the attachment of the right atrial anchor 14 to the tether 16.

Figure 14 shows the closure device 10 positioned relative to one embodiment of a delivery device 18. In Figure 14, the left atrial anchor 12 is shown deployed from the delivery device 18, while the atrial anchor Right 14 is shown in a collapsed, undeployed state within delivery apparatus 18. Delivery apparatus 18 may include a guiding catheter 20 and a right atrial positioning (RPC) catheter 22. Although not shown, guiding catheter 20 may have a preformed curve near its distal end. . Guiding catheter 20 can be any suitable conventional guiding catheter. One suitable exemplary guiding catheter is known as a "Mullins" guiding catheter, commercially released by Cook. Connected to the proximal end of guide catheter 20 is a conventional Y-adapter 80. A side arm 82 of Y-adapter 80 allows fluid communication with the lumen of guide catheter 20. Y-adapter 80 also contains a Touhy- seal. Borst 84, through which RPC 22 extends.

As previously described, RPC 22 includes balloon 24 for application to the right atrial anchor

14. Therefore, the RPC 22 is provided with a manifold 90 at a proximal end, which includes a port 92 in fluid communication with the balloon 24. The manifold 90 may further include a Touhy-Borst seal 94, through which a extend tie 16.

As mentioned, Figure 14 shows the closure device 10 after the left atrial anchor 12 has been deployed. However, before the closure device 10 is in that state, the guiding catheter would be delivered. 20 by usual techniques to the place of the PFO. Such common techniques may include

ES 2 297 563 T3 temporary use of a guide wire (not shown). Closure device 10 would then be positioned within the lumen of guide catheter 20, by suitable techniques, and advanced toward the distal end of guide catheter 20 to a position depicted in Figure 15. As shown in Figure 15, the right atrial anchor 14 is folded in a proximal direction, while the left atrial anchor 12 is folded in a distal direction within the guiding catheter 20. More specifically, the arms 40 of the atrial anchor Left 12 are folded so that they extend in a distant direction, while the arms 50 of the right atrial anchor 14 are folded so that they extend in a proximal direction. This is a preferred position of the arms in a delivery position. As an alternative , it is possible that the arms of the anchors 12 and 14 are folded so that they are extended in the same direction, either distant or proximal, or the anchor can be arranged with the arms 40 of the left atrial anchor 12 folded to extend in a proximal direction, and the arms 50 of the right atrial anchor 14 folded to extend in a distant direction.

When it is desired to deploy the left atrial anchor 12, the positioning catheter 22 is advanced in the right atrium relative to the guide catheter 20, or the guide catheter 20 is withdrawn relative to the RPC 22, or both. Since the RPC 22 is engaged with the left atrial anchor 12, the forces required to advance the left atrial anchor can be transferred by compression to abut the left atrial anchor 12.

Figures 2-10 show the successive steps for the delivery of the closure device 10. At the level of the longitudinal section represented in Figure 1, the inferior vena cava (IVC) has not been represented. In one embodiment according to a delivery method, a delivery system is passed through the IVC to gain access to the RA and the PFO. As set forth herein and depicted in Figure 2, a delivery assembly 18 including a guiding catheter 20 is advanced to and through the PFO pathway and into the LA. 18 has been represented in detail in Figure 14. In addition to the closure device 10, additional delivery components, such as a delivery sheath or a positioning catheter, may be included within the delivery assembly, as will be described below.

As set forth herein and depicted in Figure 2, in accordance with a method of delivery of the closure device 10, the guide catheter 20 is positioned through the PCO pathway with the use of a guide wire. usual (not shown). After the guide catheter 20 is positioned within the LA, the guide wire can be removed. The closure device 10, in a collapsed state, is depicted in Figure 15 as will be described below, and any delivery components are advanced into the guide catheter 20 until the closure device 10 is next. to a distal end of guide catheter 20.

Then, as illustrated in Figure 3, closure device 10 is advanced out of the distal end of guide catheter 20. Advancement is achieved by relative movement between guide catheter 20 and closure device 10 and their delivery components. Preferably, advancement is achieved by maintaining the position of guide catheter 20, and pushing delivery components in a distal direction, to push closure device 10 away from a distal end of guide catheter 20.

As long as the guide catheter 20 and delivery components are within the left atrium, only the left atrial anchor 12 is fully deployed from the guide catheter 20 in the LA. Figure 14 also shows the delivery with the left atrial anchor 12 deployed. Tether 16 extends from anchor 12 within the delivery assembly. As discussed above, the left atrial anchor 12 and the right atrial anchor 14 are preferably self-expanding structures, expanding through mechanical or thermal shape change, for example. Also at this point, the right atrial anchor 14 remains within the delivery assembly in a collapsed state.

In the next step of the delivery method, the left atrial anchor 12 is pulled against the opening of the PFO, as illustrated in Figure 5. This is done by pulling the guide catheter 20 and other components of the guide. delivery soon. As guide catheter 20 is soon withdrawn, left atrial anchor 12 will naturally seat against the wall of the septum, as shown in Figure 6.

As depicted in Figure 6, a significant portion of the PFO pathway (specifically, the portion of the pathway between the top of the primary septum and the secondary septum) runs along, and approximately parallel to, the wall. of the septum. A characteristic of the closure device 10, according to this embodiment, is that the left atrial anchor 12 and the tether 16 are flexibly connected, and the tether 16 is itself preferably flexible, to allow the tether 16 extends through the PFO pathway while the left atrial anchor 12 remains significantly opposite the left ventricular surface. Tether 16 may extend from left atrial anchor 12 at an obtuse angle. In many cases, the left atrial anchor 12, with tension applied from tether 16, can mechanically close and thereby seal the PFO, bringing the primary septum (SP) into sealing contact with the secondary septum (SS). The effectiveness of this seal can be verified on this occasion by usual techniques, such as visualization with contrast, or by means of a “Vaisalva” maneuver combined with the injection of bubbles, visualized with transesophageal or intracardiac ultrasound. If the seal is ineffective, the closure device 10 can be removed as described below, and replaced with a different device, for example, a device that includes a cover over the arms 40 of the left atrial anchor 12. Alternatively, Device 10 can be repositioned, as described below.

ES 2 297 563 T3

Once the left atrial anchor 12 is in position, the right atrial anchor 14 can be deployed. As illustrated in Figure 7, initial deployment of the right atrial anchor 14 is preferably effected with the delivery assembly and the right atrial anchor 14 folded, withdrawn far enough from the left atrial anchor 12, and the wall of the septum of the right atrium so that the right atrial anchor 14 does not impinge on the wall when initially expanded. Positioning the right atrial anchor 14 in that position, prior to deployment, also ensures that the right atrial anchor 14 will not inadvertently deploy into the PFO pathway or the left atrium. Since the right atrial anchor 14 is not permanently attached to the tether 16, the anchor 14 is free to be positioned there.

Right atrial anchor 14 is temporarily connected to a right atrial anchor positioning (RPC) catheter 22, as illustrated in Figures 8 and 9 and as described in detail below. Deployment of the right atrial anchor 14 is accomplished by relative movement of guide catheter 20 and RPC 22, either by grasping a proximal end of RPC 22 and withdrawing guide catheter 20, or by grasping guide catheter 20 and making advance to RPC 22. This relative movement results in the full deployment of the right atrial anchor 14 within the right atrium RA, as illustrated in Figure 8. At this stage of the delivery method, the tie 16 passes through the right atrial anchor 13 and preferably extends continuously through guide catheter 20 to the proximal end of delivery assembly 18. Right atrial anchor 14 is not yet attached to tether 16, and is instead connected to RPC 22. Preferably, tether 16 also extends through RPC 22.

In the next step of this embodiment of a closure device delivery method, the right atrial anchor 14 is advanced into contact with the wall of the septum of the right atrium, as illustrated in Figure 9. This is accomplished by advancing the right atrial anchor 14 and RPC 22 along the tie 16, until the right atrial anchor 14 is in a desired position relative to the left atrial anchor 12, the wall of the septum, and the PCO, and have a desired amount of tension on the left atrial anchor 12. It is preferred that the left atrial anchor 12 has sufficient tension applied for the primary septum (SP) to be brought into sealing opposition to the secondary septum (SS). This position, in many cases, can be close enough effectively, and seal the PFO. It may be preferable to also include a cloth or other covering with the right atrial anchor 14, to help provide a seal of the PFO, as described above. If desired, at this point in the delivery method the effectiveness of the closure and seal can be rechecked, by standard techniques, such as those described above. If the seal is not effective, the closure device 10 can be removed as described below, and exchanged for a different device, for example, a device that includes a cover over the arms 50 of the right atrial anchor 14. Alternatively, the position of device 10 can be modified as described below.

In the next step of the delivery method, the right atrial anchor 14 is attached to the tie 16. Figures 12 and 13 show the right atrial anchor 14 before it is attached to the tie 16. In Figures 10 and 11 shows the right atrial anchor 14 after it has been attached to the tether 16. As shown in the Figures, the RPC 22 has been disengaged from the right atrial anchor 14, and is engaged with a fixation mechanism 30 between the right atrial anchor 14 and the tether 16. In the foregoing, embodiments of tale have been described. attachment mechanisms and their associated methods for attaching anchor 14 to tether 16. These devices and methods can provide a releasable fixation mechanism that is associated with the RPC 22 so that the fixation of anchor 14 to tether 16 can be reversed at any time prior to severing tether 16.

At this point, the closure device 10 is in its final position, except that the flexible catheter 16 extends between the closure device 10 and the guide catheter 20. The closure device 10, however, is not essentially influenced by the guide catheter 20 nor by the extension of the tether 16 to and through the guide catheter 20. The effectiveness of the closure and sealing of the PFO can be verified by the usual techniques, such as contrast visualization, or by a Valsalva maneuver combined with the injection of bubbles, visualized with (TEE) or with intracardiac ultrasound.

In addition, at this stage of the delivery of the closure device 10, hemodynamic parameters such as oxygen saturation and pulmonary wedge pressure can be measured. In some rare cases, closure of a PFO can cause pulmonary arterial pressure to rise excessively, in which case the closure device 10 can be removed, as described below. It may be necessary to leave the closure device in place for several hours, or even days, to determine the full impact on hemodynamic parameters. If that is what is desired, the excess tie is simply allowed to spread from the closure device to the insertion site. At the time the device is desired for permanent implantation, the excess tie is cut off, or, if the device is desired for removal, it is removed as described below.

At this point in the delivery method, or any other point earlier in the procedure, the closure device 10 can be completely removed from the patient. This may be necessary if, for example, device 10 is not creating a complete seal, due to any of a number of causes, including, for example, that the selected device is too small. To remove the closure device 10, the RPC 22 is reapplied with the right atrial anchor 14, to reverse the locking mechanism that secures the right atrial anchor 14 to the tether 16. This allows the right atrial anchor 14 to slide smoothly. relationship to the tie 16. The right atrial anchor 14 can then be folded, removing the RPC 22 and the right atrial anchor 14 within

ES 2 297 563 T3 of delivery assembly 18, and specifically within guide catheter 20. Guide catheter 20 can then be advanced again through the PFO guide, while maintaining tension on the tether 16. Continued advancement of guide catheter 20 will advance catheter 20 over left atrial anchor 12 to fold anchor 12 into catheter 20, as illustrated in Figure 17. The entire delivery assembly, including catheter 20, RPC 22, and folded closure device 10, can then be removed from the patient. Alternatively, the closure device 10 can be redeployed and repositioned by repeating the delivery steps depicted and described in relation to Figures 2 to 10, to obtain an effective seal of the PFO pathway.

If the closure device 10, as illustrated in Figure 10, results in a satisfactory closure and sealing of the PFO, the tie 16 is cut near the right atrial anchor 14. This may be facilitated by the removal of the RPC 22 guide catheter 20 and out of tether 16. A cutting device, such as, for example, a heated loop loop (not shown), or other suitable cutting device known in the art, may be positioned proximal to the right atrial anchor 14 near the right atrial anchor 14 to cutting the tie 16. This results in the closure device 10 being deployed as illustrated in Figure 1.

An alternative embodiment of a delivery apparatus is illustrated in Figure 21. In this embodiment, instead of positioning closure device 10 directly within guiding catheter 20, closure device 10 is prepackaged within a delivery sheath 21. This entire assembly is then inserted into a catheter of guide 20 usual. The delivery sheath 21 of this embodiment essentially serves the retention functions of the guide catheter 20 of the embodiment described in connection with Figure 14. However, the embodiment of Figure 21 does not require the separate step of loading the delivery device. close 10 just prior to its introduction into the patient.

As mentioned above, the closure device 10, in accordance with one aspect of the invention, may be re-entrapped at any time prior to, and up to, the state of the closure device 10 depicted in Figure 10. This allows the position of closure device 10 to be changed in case, for example, device 10 does not provide sufficient closure and sealing of the PFO. To re-entrap the closure device 10, the delivery catheter 22 is advanced into the right atrium along the tie 16, and reapplied with the right atrial anchor 14. This reapplication takes place by positioning balloon 24 of RPC 22 within releasable locking mechanism 30, and inflating balloon 24 to entrap balloon 24 against spring portions 32a, forcing piercing pins 32 out of and away from. the tether 16. The position of the right atrial anchor 14 in the guide catheter 20 is then modified so that the arms 50 extend in a distant direction. This is done by pulling the RPC 22 and the right atrial anchor 14, into the guide catheter 20, folding the right atrial anchor 14 in a distal direction. Preferably, right atrial anchor 14 is positioned close enough within guide catheter 20 to allow space for left atrial anchor 12 within guide catheter 20. The guiding catheter 20 is then advanced toward the left atrial anchor 12 to collapse the left atrial anchor 12 so that the arms 40 also look at a distance. Alternatively, guide catheter 20 is held stationary and left atrial anchor 12 is removed within guide catheter 20. The fully recovered closure device is illustrated in Figure 17.

The various described embodiments of the closure devices and the methods and tools for their delivery are suitable for the closure of a wide variety of PFOs. For example, PFOs of a relatively long overlap between the primary septum (SP) and the secondary septum (SS) can be conveniently closed, as illustrated in Figure 1. PFOs can also be conveniently closed with a relatively short overlap between the primary septum and the secondary septum, as illustrated in Figure 18.

An alternative method of delivery and use of the closure device 10 is illustrated in Figure 19. In certain circumstances, the PFO pathway may not be ideally suited for delivery as described above. For example, the PFO pathway may be unusually long, unusually tight, or it may comprise more than one step. In a variety of electrophysiological procedures, such as mapping the left atrium and / or ablation, an access channel into the left atrium is used by drilling a small hole in the wall of the septum. primary of the atrium. A similar technique can be used to position a guiding catheter 20 through the primary septum. Using these techniques, once a small hole has been created in the wall of the septum, procedures similar to those described above can be followed, resulting in the closure device 10 positioned in position, as illustrated in Figure 19. Although the closure device 10 does not seat fully within the path of the PFO, a fabric covering one or both of the anchors 12 or 14 will effectively close the PFO.

Other embodiments of the invention will become apparent to those skilled in the art upon consideration of the specification and practice of the invention described herein. The specification and examples are only illustrative examples, the true scope of the invention being defined by the claims that follow.