Case challenge · Imaging / Fetal medicine / Maternal-fetal medicine · teaching

Twin Reversed Arterial Perfusion (TRAP · Acardiac Twin) · case challenge

Given a case, work through the care pathway step by step; the tool checks each choice and scores you. Decisions and basis are taken from this site's reviewed care pathways.

← View the full flowchartBased on Fetal therapy

Case #1Imaging / Fetal medicine / Maternal-fetal medicine

📋 Case data

Weight ratio + pump-twin cardiac functionAcardiac/pump twin weight ratio <70%, pump twin no heart failure

Data is taken from this pathway's reviewed node text. Work through the pathway step by step.

Step 1 / 1 · Weight ratio + pump-twin cardiac function

Acardiac/pump twin weight ratio + pump-twin cardiac function?

💡 TRAP occurs only in monochorionic twins. One twin = an acardiac mass (absent/rudimentary heart, absent upper body/head) reverse-perfused by the pump twin through an artery-to-artery anastomosis (Doppler shows reversed flow in the acardiac twin). ~1% of monochorionic. Pump twin at risk of high-output heart failure, polyhydramnios, prematurity, hydrops, growth restriction. First exclude pump-twin chromosomal abnormality.

For teaching. Decisions and their basis are taken from this site's reviewed care pathways; for licensed clinicians/trainees, this does not replace clinical judgment or local protocols.