Apparatus is provided, including first and second longitudinal members coupled at respective first portions thereof to tissue surrounding the ventricle. The first portion of at least the first longitudinal member is coupled to a tissue anchor, and respective second portions of the first and second longitudinal members are coupled to respective first and second leaflets of a cardiac valve. The longitudinal members are arranged with respect to the tissue anchor and the portion of tissue surrounding the ventricle in a manner which facilitates adjustment of a degree of tension of the first and second longitudinal members to draw the first and second leaflets together. A longitudinal-member-coupling device is coupled to the first and second longitudinal members, and is advanceable toward a ventricular surface of the first and second leaflets, and responsively to draw together the first and second longitudinal members. Other applications are also described.