A system for preventing thrombosis in an implantable medical device includes an implantable medical device sized for implantation at least partially within a patient's body. The device includes an at least partially electrically conductive portion that is disposed within a patient's body upon implantation, an electrode coupled to the electrically conductive portion of the device; and a power source coupled to the electrode. The power source provides a negative electric charge to the at least partially electrically conductive portion for an indefinite period of time. The device may be configured to resist thrombosis, infection, and/or undesired tissue growth via the charged conductive portion once implanted. Exemplary embodiments of the implantable medical device include a hemodialysis vasculature graft, a dialysis catheter, a coronary artery, and a heart valve.