Patent ID: 8335572

Claim:
An implantable medical device lead comprising: an insulative lead body; proximal and distal electrodes disposed on the insulative lead body; an outer conductive coil extending through the lead body, the outer conductive coil coupled to the proximal electrode at a distal end of the outer conductive coil, wherein the outer conductive coil has an outer conductive coil diameter; an inner conductive coil extending coaxially with the outer conductive coil, the inner conductive coil coupled to the distal electrode at a distal end of the inner conductive coil, the inner conductive coil comprising a filar having a filar diameter and a coil pitch that is about one to one and a half times the filar diameter, wherein the inner conductive coil transitions from a first inner conductive coil diameter to a larger second inner conductive coil diameter between the proximal electrode and the distal electrode; and an insulative layer disposed between the inner conductive coil and outer conductive coil, the insulative layer terminating at a distal side of the proximal electrode, wherein the inner conductive coil transitions from the first inner conductive coil diameter to the second inner conductive coil diameter adjacent the distal side of the proximal electrode.