Two Cases of Prenatally Diagnosed Acardiac Twin

ABSTRACT

Acardiac twin is a rare complication of multifetal gestation occurring in 1% of monozygotic twin pregnancies and 1 of 35,000 pregnancies. Acardia shows various other defects in addition to the absence of heart and the most common form is the acardius, acephalus, in which there is an absence of the fetal head and thoracic organs. The presence of an acardiac twin requires the normal (or "pump") twin to provide circulation for itself, as well as the acardiac (or "perfused") sibling. The mortality is 100% for the acardiac or perfused twin and for pump twin is about 50%, resulting from heart failure, prematurity, or cord entanglement. We report two cases of acardiac anomalies at 32 weeks gestation in 30 year-old primigravida woman and 26 weeks gestation in 30 year-old multigravida. A brief review of the literature is included.