The invention relates to an implantable device for improving or rectifying a heart valve insufficiency, comprising a closure element (1) which can be positioned in the passage area of a heart valve, in particular in the area between an atrium (2) and a ventricle (3) of the heart, and which has an upper, upstream end (1a) and a lower, downstream end (1b), wherein at least one contact strip (4) is arranged at at least one of the ends (1a, 1b) of the closure element (1), which extends away from the closure element (1) and is led back to the closure element (1) in at least one loop, wherein at least a part of the extent of the strip can be placed against the inner wall of the heart.
