Reconfirmation of the position of a catheter intravascularly placed with the assistance of ECG signals of the patient is disclosed, thus assisting in determination of subsequent catheter displacement within the patient vasculature. In one embodiment a method for reconfirming a position of an indwelling medical device within a body of a patient comprises first placing the medical device within the body of the patient using ECG signals of the patient. A first ECG signal profile relating to an initial position of the indwelling medical device after initial placement of the medical device is stored. A second ECG signal profile relating to the position of the indwelling medical device at a time subsequent to initial placement of the medical device is then acquired. The first ECG signal profile is compared with the second ECG signal profile to determine whether displacement of the indwelling medical device has occurred.
