Abstract: Described here are systems and methods for affecting tissue within a body to form a lesion. Some systems comprise tissue-affecting devices, devices that guide the advancement of the tissue-affecting elements to a target tissue region, devices that locate and secure tissue, and devices that help position the tissue-affecting devices along the target tissue. The methods described here comprise advancing a first tissue-affecting device to a first surface of a target tissue, advancing a second tissue-affecting device to a second surface of the target tissue, and positioning the first and second devices so that a lesion may be formed in the tissue between them. In some variations, the devices, systems, and methods described here are used to treat atrial fibrillation by ablating fibrillating tissue from an endocardial surface and an epicardial surface of a heart. Methods of closing, occluding, and/or removing the left atrial appendage are also described.

Abstract: A novel catheter-based system which ligates the left atrial appendage (LAA) on the outside of the heart, preferably using a combination of catheters and/or instruments, e.g., a guide catheter positioned inside the left atrial appendage which may assist in locating the left atrial appendage and/or assist in the optimal placement of a ligature on the outside of the appendage, and a ligating catheter and/or instrument outside the heart in the pericardial space to set a ligating element at the neck of the left atrial appendage.

Abstract: Closure devices and methods are provided for ligating tissue, such as the left atrial appendage. Generally, the closure devices include an elongate body, a snare loop assembly comprising a snare and a suture loop, and a shuttle connected to the snare and releasably coupled to the elongate body and retractable therein. In some variations, the shuttle may be configured to fit into the lumen. In other variations, a handle may be attached to the elongate body, and the handle may comprise a track and a snare control coupled to the track. The handle may be configured to release the shuttle from the elongate body and allow movement of the snare control along the track to retract the snare loop and the shuttle into a lumen of the elongate body.

Abstract: Described here are devices, systems, and methods for closing the left atrial appendage. The methods described here utilize a closure device for closing the left atrial appendage and guides or expandable elements with ablation or abrading elements to ablate or abrade the left atrial appendage. In general, these methods include positioning a balloon at least partially within the atrial appendage, positioning a closure assembly of a closure device around an exterior of the atrial appendage, inflating the balloon, partially closing the closure assembly, ablating the interior tissue of the atrial appendage with the inflated balloon, removing the balloon from the atrial appendage, and closing the atrial appendage with the closure assembly.

Abstract: Described here are closure devices and methods for ligating tissue, such as the left atrial appendage. The closure devices may comprise a snare loop assembly comprising a snare and a suture loop releasably attached thereto. The snare may be releasable from an elongate body of the closure device. In some instances, the closure device may comprise one or more markers to allow a user to determine whether the snare loop assembly is twisted.

Abstract: Described herein are tissue closure devices and methods for ligating a target tissue, such as the left atrial appendage. The tissue closure device may have an elongate body, a snare at least partially housed within the elongate body, a suture at least partially housed within the elongate body, and a tightening element coupled to the suture. The suture may have a suture loop, and the tightening element may be configured to decrease the size of the suture loop when the area of a tissue within the suture loop decreases.

Abstract: Surgical and percutaneous devices for closing tissue, for example, the left atrial appendage, may have an elongate body with a stiffened proximal portion, a flexible middle portion, a distal portion, a closure element with a loop having a continuous aperture therethrough, and a suture loop. The closure devices may have a malleable member attached to the elongate body that may be configured to retain a curve after a force is applied to the malleable member. System and methods for closing the left atrial appendage may utilize a closure device and a curved guide device, and the closure device and curved guide device may be self-orienting.

Abstract: Methods for closing a left atrial appendage rely on introducing a closure tool from a location beneath the rib cage, over an epicardial surface, and to the exterior of the left atrial appendage. The closure device may then be used to close the left atrial appendage, preferably at its base, by any one of a variety of techniques. One specific technique uses graspers and a closing loop. Methods may include advancing a closure tool adjacent to the left atrial appendage using a sub-xiphoid approach and closing the left atrial appendage using the closure tool. Methods may also include advancing a loop adjacent to the left atrial appendage using a sub-xiphoid approach and closing the left atrial appendage using the loop.

Abstract: The methods and apparatus for lead placement on a surface of the heart are employed using an elongated body having proximal and distal end portions. The body defines a lead receiving passageway extending between a proximal inlet and a distal outlet for receiving a lead therethrough for contact with the heart surface. The elongated body is adapted for insertion between a pericardium and an epicardial surface. At least a portion of the body may have a non-circular cross-sectional shape adapted to retain the body orientation between the pericardium and the epicardial surface.

Abstract: A novel catheter-based system that ligates the left atrial appendage (LAA) on the outside of the heart, preferably using a combination of catheters and/or instruments, e.g., a guide catheter inserted into the interior of the left atrial appendage that may assist in locating the left atrial appendage and/or assist in the optimal placement of a ligature or constricting element on the outside of the appendage, and a ligating catheter and/or instrument outside the heart in the pericardial space to set the ligature or constricting element at the neck of the left atrial appendage.

Abstract: Described here are devices, systems and methods for closing the left atrial appendage. Some of the methods described here utilize one or more guide members having alignment members to aid in positioning of a closure device. In general, these methods include advancing a first guide having a first alignment member into the left atrial appendage, advancing a second guide, having a second alignment member, into the pericardial space, aligning the first and second alignment members, advancing a left atrial appendage closure device into the pericardial space and adjacent to the left atrial appendage, and closing the left atrial appendage with the closure device. In these variations, the closure device typically has an elongate body having a proximal end and a distal end, and a closure element at least partially housed within the elongate body. The closure element comprises a loop defining a continuous aperture.

Abstract: Described here are closure devices and methods for ligating tissue, such as the left atrial appendage, and tensioning devices and mechanism for actuating these devices. The tensioning mechanisms and devices may allow a user to apply one or more predetermined forces to a suture or other portion of the closure devices. The closure devices may comprise a suture loop releasably attached to a snare loop assembly, and a tensioning mechanism or device may be configured to tighten the suture loop and/or release the suture loop from the snare loop assembly.

Abstract: Described here are devices and systems for accessing and delivering devices to a heart. The left atrial appendage may be used as an access port to allow pericardial access to internal structures of the heart. Systems that may be used to provide access to the heart via the left atrial appendage may comprise a first access element with a first alignment member, a second access element with a second alignment member, a piercing element, and an exchange element. A piercing element may be advanced to pierce the wall of the left atrial appendage to form an access site therethrough. Optionally, an exchange element may be advanced to initiate a track between the inside and outside of the left atrial appendage, which may be used for device delivery. Some systems may further comprise a left atrial appendage stabilization device.

Abstract: Described here are closure devices and methods for ligating tissue, such as the left atrial appendage. The closure devices may comprise a snare loop assembly comprising a snare and a suture loop releasably attached thereto. The snare may be releasable from an elongate body of the closure device. In some instances, the closure device may comprise one or more markers to allow a user to determine whether the snare loop assembly is twisted.

Abstract: Described here are devices and methods for accessing the pericardial space. The access devices may include a piercing member such as a needle and a proximal shoulder having a contact surface for contacting the pericardium as the piercing member pierces the pericardium. In some instances, the distance between the piercing member and the proximal shoulder may be adjustable.

Abstract: A novel catheter-based system which ligates the left atrial appendage (LAA) on the outside of the heart, preferably using a combination of catheters and/or instruments, e.g., a guide catheter positioned inside the left atrial appendage which may assist in locating the left atrial appendage and/or assist in the optimal placement of a ligature on the outside of the appendage, and a ligating catheter and/or instrument outside the heart in the pericardial space to set a ligating element at the neck of the left atrial appendage.

Abstract: Described here are devices for closing one or more tissues, and handles for controlling these devices. Generally, the devices described here comprise a snare loop assembly, wherein the snare loop assembly comprises a snare and a suture loop, and a handle for controlling the snare loop assembly. In some variations the snare loop assembly may comprise a retention member that may releasably connect the suture loop to the snare. In other variations the devices comprise one or more force-reducing suture locks to help prevent the suture loop from inadvertently disengaging from the snare loop assembly. In still other variations, the excess-suture management features. The handles described here may be configured to remove excess suture from a suture loop, and may also be configured to release the suture loop from the snare loop assembly.

Abstract: The methods and apparatus for lead placement on a surface of the heart are employed using an elongated body having proximal and distal end portions. The body defines a lead receiving passageway extending between a proximal inlet and a distal outlet for receiving a lead therethrough for contact with the heart surface. The elongated body is adapted for insertion between a pericardium and an epicardial surface. At least a portion of the body may have a non-circular cross-sectional shape adapted to retain the body orientation between the pericardium and the epicardial surface.

Abstract: Devices and methods for accessing the pericardial space of a heart are described here. Access devices may generally comprise a tissue-engaging member, a tissue-piercing member, and a guide element. The access device may be introduced to the surface of a pericardium, where the tissue-engaging member may be deployed to engage a portion of the pericardium without engaging the epicardial surface of the heart. Once the access device has engaged the pericardium, the device may manipulate the pericardium to increase the distance between a portion of the pericardium and the epicardial surface of the heart. Once a sufficient space has been created, the tissue-piercing member may be advanced to pierce the pericardium and enter the pericardial space. The guide element may then be introduced into the pericardial space to provide an access pathway to the heart for other devices.

Abstract: Described here are devices, systems and methods for closing the left atrial appendage. Some of the methods described here utilize one or more guide members having alignment members to aid in positioning of a closure device. In general, these methods include advancing a first guide having a first alignment member into the left atrial appendage, advancing a second guide, having a second alignment member, into the pericardial space, aligning the first and second alignment members, advancing a left atrial appendage closure device into the pericardial space and adjacent to the left atrial appendage, and closing the left atrial appendage with the closure device. In these variations, the closure device typically has an elongate body having a proximal end and a distal end, and a closure element at least partially housed within the elongate body. The closure element comprises a loop defining a continuous aperture.