Patent ID: 8135476

Claim:
An implantable medical electrical lead for electrical stimulation of body tissue comprising: a lead body; at least one shape memory polymer portion that forms a section of the lead body such that the shape memory polymer portion is between two linear portions of the lead body, the shape memory polymer portion having a first configuration where the shape memory polymer portion has a coaxial relationship with the two portions of the lead body and has a second configuration, wherein the second configuration is obtained upon exposure of the shape memory polymer portion to a transition stimulus, wherein the second configuration of the modifiable portion exhibits a greater resistance to movement of the lead within the body tissue than does the first configuration and wherein the second configuration is a helical configuration with a coil diameter of the helical configuration being smaller at a distal edge of the shape memory polymer portion than at a proximal end of the shape memory polymer portion and with a longitudinal axis of a helix formed by the helical configuration being co-linear with a longitudinal axis of the lead body; and at least one electrode configured to provide electrical stimulation of body tissue, wherein the lead body has a proximal end and a distal end.