A system for providing indications of location of a catheter tip within a patient, the system including a memory storing synthesized blood pressure waveform parameters representative of a first plurality of catheter tip locations in a second plurality of representative patients, real time patient blood pressure waveform parameter acquisition circuitry operative to acquire real time blood pressure waveform parameters of a patient currently undergoing catheterization, which parameters contain information useful in ascertaining the location of a catheter tip in the patient and real time patient catheter tip location ascertaining circuitry operative to receive the real time patient blood pressure waveform parameters from the acquisition circuitry and to employ the synthesized blood pressure waveform parameters for providing a real time indication of catheter tip location in the patient.