A system for controlling deployment of an implantable medical includes an implantable medical device and a gripper mechanism. One or both of the medical device and the gripper mechanism are made from a shape-memory alloy material having a temperature at which the material will transition from a martensite state to an austenite state. The shape-memory alloy material has a transition temperature that is higher than a normal body temperature and a wide hysteresis band, with a temperature at which the material transitions back into the martensite state being below a normal body temperature. The medical device will expand or change shape upon being heated by a current passing therethrough, but will not transition into its remembered shape until such current is applied.
