TECHNICAL FIELD

The disclosure relates generally to percutaneous medical devices and more particularly to percutaneous occlusive medical devices for implantation into the left atrial appendage (LAA) of a heart.

BACKGROUND

Atrial fibrillation (AF) a common sustained cardiac arrhythmia affecting over 5.5 million people worldwide. Atrial fibrillation is the irregular, chaotic beating of the upper chambers of the heart. Electrical impulses discharge so rapidly that the atrial muscle quivers, or fibrillates. Episodes of atrial fibrillation may last a few minutes or several days. The most serious consequence of atrial fibrillation is ischemic stroke. It has been estimated that up to 20% of all strokes are related to atrial fibrillation. Most atrial fibrillation patients, regardless of the severity of their symptoms or frequency of episodes, require treatment to reduce the risk of stroke. The left atrial appendage (LAA) is a small organ attached to the left atrium of the heart as a pouch-like extension. In patients suffering from atrial fibrillation, the left atrial appendage may not properly contract with the left atrium, causing stagnant blood to pool within its interior, which can lead to the undesirable formation of thrombi within the left atrial appendage. Thrombi forming in the left atrial appendage may break loose from this area and enter the blood stream. Thrombi that migrate through the blood vessels may eventually plug a smaller vessel downstream and thereby contribute to stroke or heart attack. Clinical studies have shown that the majority of blood clots in patients with atrial fibrillation are found in the left atrial appendage. As a treatment, medical devices have been developed which are positioned in the left atrial appendage and deployed to close off the ostium of the left atrial appendage. Over time, the exposed surface(s) spanning the ostium of the left atrial appendage becomes covered with tissue (a process called endothelization), effectively removing the left atrial appendage from the circulatory system and reducing or eliminating the number of thrombi which may enter the blood stream from the left atrial appendage.

A continuing need exists for improved medical devices and methods to control thrombus formation within the left atrial appendage of patients suffering from atrial fibrillation.

SUMMARY

In a first aspect, an occlusive implant may comprise an expandable framework configured to shift between a collapsed configuration and an expanded configuration, and an occlusive element disposed on the expandable framework. The expandable framework may include a plurality of anchor members extending radially outward from the expandable framework. At least some of the plurality of anchor members may each have a barb projecting circumferentially therefrom.

In addition or alternatively, and in a second aspect, each of the plurality of anchor members includes a body portion and a tip portion.

In addition or alternatively, and in a third aspect, the barb projecting circumferentially from at least some of the plurality of anchor members projects from the body portion of its respective anchor member.

In addition or alternatively, and in a fourth aspect, the body portion of each anchor member is attached to the expandable framework at a base of its respective anchor member.

In addition or alternatively, and in a fifth aspect, each barb includes a forward surface facing towards the tip portion of its respective anchor member, and a rear surface facing towards the base of its respective anchor member.

In addition or alternatively, and in a sixth aspect, the rear surface is positioned at an obtuse angle to the body portion.

In addition or alternatively, and in a seventh aspect, the forward surface is positioned at an obtuse angle to the body portion.

In addition or alternatively, and in an eighth aspect, an intersection of the forward surface with the rear surface forms a barb tip, the barb tip being rounded.

In addition or alternatively, and in a ninth aspect, each barb comprises a semi-elliptical nub.

In addition or alternatively, and in a tenth aspect, the expandable framework and the plurality of anchor members are formed from a unitary tubular member.

In addition or alternatively, and in an eleventh aspect, an occlusive implant system may comprise a catheter having a lumen extending from a proximal opening to a distal opening, a core wire slidably disposed within the lumen, and an occlusive implant having an expandable framework configured to shift between a collapsed configuration and an expanded configuration and an occlusive element disposed on the expandable framework. The expandable framework may include a plurality of anchor members extending radially outward from the expandable framework. At least some of the plurality of anchor members may each have a barb projecting circumferentially therefrom. The occlusive implant may be releasably connected to a distal portion of the core wire.

In addition or alternatively, and in a twelfth aspect, the occlusive implant is disposed within the lumen proximate the distal opening in the collapsed configuration.

In addition or alternatively, and in a thirteenth aspect, a tip portion of each of the plurality of anchor members extends towards a proximal end of the occlusive implant.

In addition or alternatively, and in a fourteenth aspect, the occlusive element extends distally past all of the plurality of anchor members.

In addition or alternatively, and in a fifteenth aspect, the plurality of anchor members each extend through the occlusive element.

In addition or alternatively, and in a sixteenth aspect, an occlusive implant may comprise an expandable framework configured to shift between a collapsed configuration and an expanded configuration, and an occlusive element disposed over an outer surface of the expandable framework. The expandable framework may include a plurality of anchor members extending radially outward from the expandable framework and through the occlusive element. At least some of the plurality of anchor members may each have two barbs projecting circumferentially therefrom.

In addition or alternatively, and in a seventeenth aspect, each barb comprises a semi-elliptical nub, each semi-elliptical nub on a particular anchor member extending in a common circumferential direction from the particular anchor member.

In addition or alternatively, and in an eighteenth aspect, the two barbs extend in opposing circumferential directions from their respective anchor member.

In addition or alternatively, and in a nineteenth aspect, a distal portion of the occlusive element is attached to the expandable framework and attachment of the distal portion of the occlusive element to the expandable framework is devoid of sutures and adhesives.

In addition or alternatively, and in a twentieth aspect, each of the plurality of anchor members has at least one barb projecting circumferentially therefrom.

The above summary of some embodiments, aspects, and/or examples is not intended to describe each embodiment or every implementation of the present disclosure. The figures and the detailed description which follows more particularly exemplify these embodiments.

