1. A system for tracking a location of a medical device within a vasculature of a patient, the system comprising: an endovascular electrode disposed on the medical device and capable of detecting an endovascular ECG signal; a display for depicting an image of the endovascular ECG signal; a storage device including one or more instructions; and a module including a processor, the module communicatively coupled to the storage device, wherein when the processor executes the one or more instructions, the processor identifies an endovascular ECG waveform complex of the endovascular ECG signal and calculates an absolute value of an energy of the endovascular ECG waveform complex in order to enable determination of a position of the medical device within the vasculature.