Apparatus & methods for optimizing anchoring force are described herein.
In securing tissue folds, over-compression of the tissue directly
underlying the anchors is avoided by utilizing tissue anchors having
expandable arms configured to minimize contact area between the anchor
and tissue. When the anchor is in its expanded configuration, a load is
applied to the anchor until it is optimally configured to accommodate a
range of deflections while the anchor itself exerts a substantially
constant force against the tissue. Various devices, e.g., stops, spring
members, fuses, strain gauges, etc., can be used to indicate when the
anchor has been deflected to a predetermined level within the optimal
range. Moreover, other factors to affect the anchor characteristics
include, e.g., varying the number of arms or struts of the anchor,
positioning of the arms, configuration of the arms, the length of the
collars, etc.