An implantable medical lead having a modified electrode surface for imparting current density directionality within an electrode is disclosed. An implantable medical lead includes a lead body having a proximal section and a distal section having a pre-biased shape configured to secure the lead to an inner wall of a blood vessel. An electrode coupled to the distal section of the lead body includes a number of surface features on an inactive portion of the electrode that impart a current density directionality towards an active portion of the electrode that contacts the inner wall of the vessel. Methods for imparting current density directionality within an implantable lead electrode are also disclosed.