Device and method for occluding the left atrial appendage

Abstract

An implantable medical device for insertion in the left atrial appendage includes a cap coupled to a frame. The cap constrains movement of the legs of the frame during collapse and expansion of the device, such that the device can be deployed, recalled and redeployed without the device being damaged or the legs of the frame getting tangled.

We claim: 
     
         1 . An implantable medical device for insertion in a left atrial appendage of a patient comprising:
 a frame;   a cap connected to said frame;   a membrane coupled to and covering a portion of said frame.   
     
     
         2 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 1  wherein:
 said frame includes limbs terminating in a frame joint element; 
 said cap including spokes emanating from a cap center hub and terminating in a cap joint element; 
 said frame joint element coupled to said cap joint element. 
 
     
     
         3 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 1  wherein each said limb is coupled to one spoke. 
     
     
         4 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 2 , wherein one of said joint elements is a male-shaped member and said mating joint element is a female-shaped member. 
     
     
         5 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 4  wherein one of said joint members is an elongate tang and the other of said joint members is an aperture defined by said spoke that is sized and shaped to receive said tang. 
     
     
         6 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 2  wherein:
 said cap joint element is an elongate tang; 
 said frame joint element is an aperture in said limb; 
 said hinges formed by the insertion of said elongate tang into said aperture. 
 
     
     
         7 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 6  wherein said device defines an interior space and wherein said spoke tangs pass through said limb slots from the exterior of the device to the interior space. 
     
     
         8 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 6  wherein said tang has a flange adjacent its terminating end, said flange being sized such that it slides through said mating joint element aperture when in a first orientation thereto, but is prohibited from sliding through said aperture when in another orientation with respect thereto. 
     
     
         9 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 8 , wherein said aperture is a rectangular slot having a width that is smaller than the largest dimension of said flange has a largest dimension and said slot having a length that is longer than the largest dimension of said flange. 
     
     
         10 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 2  wherein:
 the device has a longitudinal axis and is deformable between a deployed configuration in which said spokes extend generally radially outward from said axis and a second undeployed configuration in which said spokes extend generally parallel to and are concentric with said axis and in which said cap is substantially enclosed within said frame in said undeployed configuration. 
 
     
     
         11 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 10  wherein:
 said spokes are hingedly coupled to said center hub. 
 
     
     
         12 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 2  wherein:
 said spokes of said distal cap are continuous with said cap center and wherein said coupling of said spokes to said hub is achieved through flexing of said spokes with respect to said hub. 
 
     
     
         13 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 12 , wherein said distal cap has a tissue-driving region and a tissue-following region. 
     
     
         14 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 11  wherein an anterior direction extends along the longitudinal axis of the device from its proximal end towards its distal end and wherein the terminating ends of said limbs lie in an anterior plane and wherein a portion of said distal cap extends, in the anterior direction, beyond said anterior plane forming a bumper and wherein said distal cap bumper portion is atraumatic at the implant site. 
     
     
         15 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 14  wherein said bumper portion of said distal cap lies at the radial edge of the device. 
     
     
         16 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 14 , wherein each said spoke includes a curved portion between said center hub and its terminating end and wherein said curved portion has a radius of curvature that lies within the interior of a volume defined by the device. 
     
     
         17 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 10 , wherein the terminating ends of said limbs lie in an anterior plane and wherein said hub lies posterior to said anterior plane when said device is in its deployed configuration and when it is in its undeployed configuration 
     
     
         18 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 1 :
 said frame includes retention members.   
     
     
         19 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 18  wherein each retention member has a barb adjacent a distended ridge of the frame. 
     
     
         20 . An implantable medical device for insertion in a left atrial appendage of a patient according to  claim 19  wherein said distended ridge limits the penetration depth of said hook into tissue. 
     
     
         21 . A method of implanting a medical device for insertion in a left atrial appendage comprising the steps of:
 a) providing an implantable medical device having a frame with retension members extending radially outwardly from said device, a cap connected to said frame and a membrane coupled to and covering a portion of said frame;   b) collapsing said device within a delivery catheter;   c) implanting said device by deploying said device from said catheter, said device expanding to its natural state, with retention members engaging adjacent tissue;   d) after implanting said device, retracting said device into said catheter; and   e) after retracting the device, re-implanting the device by redeploying said device from said catheter, said device expanding to its natural state, with retention members engaging adjacent tissue.