An apparatus including a tether, and an aptation device coupled to the tether at a position corresponding to a location to contact cusps of an atrioventricular valve during systole, wherein the tether and aptation device are suitable for percutaneous delivery to a patient. The electronic circuit may include a controllable conductivity device having high conductivity when the battery of the first type provides power to a load, and a battery charging control circuit for reducing the conductivity of the controllable conductivity device for limiting the charging of the battery. An elevated sourcedrain structure, defined by the boundaries of the disposable spacer, is then formed epitaxially.