Tissue anchors with hemostasis seal

A method comprising:

• providing a tissue anchor that comprises (a) a shaft, (b) a head connected to a proximal portion of the shaft, which comprises a seal, and (c) a tissue-coupling element, which extends from a distal end of the shaft;
• introducing, during a transcatheter procedure, the tissue anchor into a cardiac chamber of a heart of a subject, while the tissue-coupling element is constrained by a deployment tool;
• delivering the tissue-coupling element through a wall of the heart;
• and
• at least partially releasing the tissue anchor from the deployment tool such that (a) the tissue-coupling element is unconstrained by the deployment tool, (b) the head is coaxial with a central longitudinal axis of the shaft, and (c) the tissue-coupling element is generally orthogonal to the central longitudinal axis of the shaft and is shaped such that if the tissue-coupling element were to be projected onto a plane that is perpendicular to the central longitudinal axis, (i) at least 80% of an area of a projection of the tissue-coupling element on the plane would fall within a first angle of 180 degrees in the plane having a vertex at the central longitudinal axis, and (ii) the area would partially overlap, at least 3 mm from the vertex, both rays of a second angle of between 45 and 180 degrees in the plane having the vertex at the central longitudinal axis, wherein both the rays fall within the first angle.