Twin reversed arterial perfusion (TRAP) sequence ( acardia) fetal ultrasound.

Описание: #fetalmedicine #GeetanjaliHospital #fetaltherapy #10weekspregnant

Twin reversed arterial perfusion (TRAP) sequence, also known as acardia, is a rare anomaly unique to multiple gestation in which one twin has an absent heart (acardiac twin) and the other twin is normal (pump twin).

The fundamental requirement for the TRAP sequence is the development of arterial-to-arterial vascular anastomoses between the umbilical arteries of twins early in embryogenesis.

Today come across a rare case of dichorionic triamniotic triplet conception. So there are basically two gestational sacs Sac 1 contains single fetus with Increased NT while Sac 2 contains monochorionic diamniotic acardiac Twins. The acardiac fetus shows anencephaly, omphalocele, absence of upper limbs, edematous soft tissue and large cystic hygromalike spaces in the skin.the umbilical cord to the acardiac twin is quite short.

The pump twin retrogradely perfuses the other twin with deoxygenated blood along the umbilical artery/arteries to the iliac artery/arteries to the abdominal aorta. The lower limbs and abdominal organs supplied by the iliac arteries and abdominal aorta preferentially receive a better blood supply and usually develop better than the upper part of the body.

The pump twin is usually morphologically normal and the risk of aneuploidy is 9%.

Intrafetal radiofrequency ablation of the cord of the acardius when indicated is associated with 95% pump twin survival.