An electrical lead includes an elongate body having a proximal end portion and
a distal end portion, a first electrode disposed adjacent and joined to the distal
end portion of the elongate body. Current flow within the first electrode is limited
when a predetermined condition occurs, such as the generation of an electromagnetic
field having a predetermined frequency range. The medical electrical lead may further
comprise one or more second electrodes disposed adjacent the first electrode and
joined to the elongate body to shunt current to body tissue when the predetermined
condition occurs.