A Pilot Clinical PEP Monitor

An instrument for the continuous measurement of pre-ejection period (PEP) in the human fetus using Doppler ultrasound is presented. An important feature of the instrument is its ability to track the continuously changing location of the reflections. The design includes a recently developed nonlinear filtering technique that is quite insensitive both to the large amounts of noise of biologic origin and the random dynamic amplitude variations. The efficiency of the scheme is illustrated by simulated and clinical tests.