Extensible implantable medical lead

1. An extensible medical lead having at least one proximal contact and at least one distal electrode, the lead comprising:

at least one conductive filer electrically coupled between said proximal contact and said distal electrode;

an inner jacket surrounding the at least one conductive filer, said inner jacket comprising a longitudinally compressed material doped with a conductor; and

an outer jacket forming an outermost surface of the lead for housing said at least one conductive filer and inner jacket, said outer jacket being made of a longitudinally compressed material doped with a conductor, the outer jacket having a helical channel therein and further comprising a coiled outer filer that resides within said channel.

2. A lead according to claim 1 wherein said inner jacket comprises polytetrafluoroethylene.

3. A lead according to claim 1 wherein the longitudinally compressed material of the inner jacket is doped with a metal.

4. A lead according to claim 3 wherein the longitudinally compressed material of the outer jacket is doped with a metal.

5. A lead according to claim 3 wherein said at least one conductive filer is coiled.

6. A lead according to claim 5 wherein said at least one conductive filer has a diameter no greater than 0.004 inch.

7. A lead according to claim 1 , further comprising a plurality of coiled filers and a plurality of inner jackets with each coiled filer of the plurality being surrounded by an inner jacket of the plurality, each coiled filer of the plurality having a longitudinal axis substantially parallel to a longitudinal axis of said jacket.

8. A lead according to claim 7 wherein adjacent ones of said plurality of coiled filers are wound in substantially opposite directions.

9. A lead according to claim 1 wherein said outer filer has a cross-section with flat sides.