A Rare Case of Acardiac Twin: A Case Report

Acardiac twin occurrence is rare. It is a serious complication of monozygotic multiple gestations. This is due to the sharing of blood supply between the twins in monozygotic gestation. This is called the twin reversed arterial perfusion occurring only in monozygotic twins. Monozygotic twins occur when the fertilized egg divides very early 4-8 days after fertilization. In monozygotic twin, acardiac twin is one of the twin that fails to develop head, arms and heart and gets its entire blood supply from the structurally normal pump twin. Acardiac twin has 100% mortality. Pump twin though structurally normal suffers due to heart failure and prematurity and has high morbidity and mortality all due to pumping blood to the acardiac twin. The acardiac twin receives all its blood supply from the pump twin through anastomotic channels, the term reversed perfusion is used to describe this condition because blood enters the acephalic twin through umbilical artery and exit through umbilical vein which is opposite to the normal blood supply. The acardiac twin loses direct vascular connection with the placental villi and receives its entire blood supply from the pump twin. Here we are presenting a primi gravida of 24-26 weeks of gestation with twin gestation of monochorionic di amniotic type in preterm labor. One of the twin was acardiac acephalous and another a pump twin with hydrops.