Body lumen wall invagination

1 . A method for left atrial appendage (LAA) invagination, comprising:

convexing a portion of the LAA wall into the LAA, wherein said convexing comprises convexing said LAA wall portion by applying suction from a collapsible suction cup contacting said LAA wall on said LAA wall portion;

grasping said convexed LAA wall portion within the LAA, following said convexing;

invaginating said LAA at least partly into the left atria (LA) using said convexed LAA portion;

wherein said grasping comprises controllably collapsing said collapsible suction cup on said convexed LAA portion with a force sufficient to hold said convexed LAA portion during said invaginating.

2 . A method according to claim 1 , wherein said convexing comprises convexing said LAA wall portion to a distance of up to 2 cm into the LAA.

3 . A method according to claim 1 , wherein said convexing comprises applying force on an inner surface of said LAA wall from within the LAA, which is sufficient to convex said LAA wall portion into the LAA.

4 . A method according to claim 3 , wherein said applied force is atraumatic to the LAA wall.

5 . A method according to claim 1 , wherein said convexing and said grasping are separated in time.

6 . A method according to claim 1 , wherein said convexing comprises applying a first force on a region of said LAA wall which is sufficient to convex said LAA wall portion, and wherein said grasping comprises applying a second force on a smaller portion of said region to grasp said convexed LAA wall portion.

7 . A method according to claim 1 , wherein said convexing comprises convexing said LAA wall portion by applying suction from a suction tube on said LAA wall portion, and wherein said grasping comprises grasping said convexed LAA portion using a tissue grasper that applies a force on a small area of said convexed LAA wall portion.

8 . A method according to claim 1 , wherein said grasping comprises tightening a loop around said convexed LAA wall portion.

9 . A method according to claim 8 , wherein said tightening comprises reversibly tightening said loop around said convexed LAA wall portion, and wherein said method comprises releasing said loop from said convexed LAA after said LAA is invaginated into said LA.

10 . A tissue grasper comprising:

an elongated tubular body having a proximal end and a distal end, wherein said proximal end is connected to a vacuum source;

a collapsible distal suction cup coupled to said distal end, defining a distal opening and an internal lumen, wherein said collapsible distal suction cup is configured to apply vacuum from said vacuum source through said distal opening on a LAA wall with a force sufficient to convex a portion of said LAA wall into said lumen, and to controllably collapse on said convexed portion of the LAA with a force sufficient to hold said convexed portion in said lumen;

wherein said collapsible distal cup comprises a plurality of spaced-apart extensions movably coupled to said elongated tubular body and arranged on a circumference of the elongated tubular body distal end, wherein in an open expanded state of said collapsible distal cup said plurality of spaced-apart extensions are tilted outwardly, and wherein in a collapsed state of said collapsible distal cup, said plurality of spaced-apart extensions move inwardly and press against said convexed portion of said LAA with a force sufficient to hold said convexed LAA portion in said lumen;

wherein at least some of said plurality of spaced-apart extensions are interconnected by at least one wire, wherein application of force on said wire controllably move said collapsible distal cup between said open expanded state and said collapsed state, by moving said at least some of said plurality of spaced-apart extensions.

11 . A tissue grasper according to claim 10 , comprises one or more layers of sheet material interconnecting said plurality of spaced-apart extensions to form an enclosed lumen of said collapsible distal cup.

12 . A tissue grasper according to claim 11 , wherein said one or more layers of sheet material comprise an elastic sheet material.

13 . A tissue grasper according to claim 10 , wherein said collapsible distal suction cup comprises a distal leading edge configured to contact said LAA wall, and wherein said distal leading edge is covered with a smooth foldable fabric material configured to form a tight interface between said distal edge and said LAA wall.

14 . A system for LAA closure comprising:

at least one tissue grasper according to claim 10 and one or more of, at least one ligator configured to pass within said catheter, to extend from said catheter distal opening, and to close said LAA and/or a LAA isolator configured to cover a LAA opening within the LA, to prevent flow of particles, debris and/or blood clots from said LAA into said LA.