MCA-PSV (Middle Cerebral Artery Peak Systolic Velocity)

MCA-PSV (Middle Cerebral Artery Peak Systolic Velocity): Peak systolic velocity in the fetal middle cerebral artery; values >1.5 MoM indicate fetal anemia and trigger further evaluation.

Middle cerebral artery peak systolic velocity (MCA-PSV) is a Doppler measurement used to screen for fetal anemia. Elevated MCA-PSV (>1.5 MoM for gestational age) indicates increased cardiac output from compensatory hyperdynamic circulation in anemic fetuses, prompting amniocentesis or fetal transfusion. It has replaced invasive cordocentesis as the primary non-invasive fetal anemia screening tool.