Twin Reversed Arterial Perfusion (TRAP) Sequence: A Rare Case Report of an “Acardiac” Twin

Abstract

A 32 year-old-pregnant female, presented to the labour and delivery department with contractions and leaking fluid. A vaginal mass was noted on digital examination. Obstetrical ultrasound demonstrated a twin pregnancy with a normal male fetus and a dysmorphic fetus with cardiac activity. Cesarean section was performed due to premature rupture of membranes (PROM) and ultrasound findings. A normal live male infant was delivered, required minimal neonatal care, and is healthy to date. A non-viable anomalous twin and the shared placenta was sent for autopsy. Pathology diagnosis was twin reversed arterial perfusion (TRAP) sequence and hemiacardius twin. TRAP sequence was a prenatal differential diagnosis but seemed unlikely with uncharacteristic findings and rare incidence. This case report emphasizes the importance of early and accurate ultrasound detection of multiple pregnancies, fetal autopsy, and the complexity of TRAP sequence.