A system having a catheter having a distal pressure sensitive capacitive element providing an impedance and phase shift which varies responsive to the amount of pressure from blood external the catheter, a detector having electronics for determining the impedance and/or phase shift. This impedance and or phase shift corresponds to the pressure of the blood about the distal end of the catheter. When the catheter is inserted into a patient's body, the impedance or phase shift is detected quasi wirelessly without special signal communication means like optical fibers or electrical wires from outside the patient's body utilizing the patient as a ground path and the catheter shaft as an electrical conductor.
