Apparatus and methods are described including an implant structure configured to treat a native atrioventricular valve of a patient, the implant structure including a sleeve having a lumen and at least one end, the at least one end being shaped so as to define an opening. A closure element is disposed in a vicinity of the at least one end, the closure element being configured to facilitate closure of the opening. A contracting mechanism is coupled to the implant structure and configured to contract at least a contraction-facilitated portion of the implant structure. Other applications are also described.
