Patent ID: 8457763

Claim:
An implantable medical electrical lead for electrical stimulation of body tissue comprising: at least one modifiable portion that exhibits a first configuration when exposed to a first temperature and a second configuration when exposed to a second temperature, 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 the second temperature is higher than the first temperature; and at least two electrodes configured to provide electrical stimulation of body tissue, wherein the lead has a proximal end and a distal end, wherein one of the at least two electrodes is a most proximal electrode on the lead, wherein the modifiable portion is disposed proximal to the most proximal electrode, and wherein the distance between the most proximal electrode and the at least one modifiable portion, referred to as a spacer distance, s, is from about 2 mm to about 30 mm.