Introduction
Twin to twin transfusion syndrome (TTTS) is a rare and serious condition
that occurs in monochorionic (MC) pregnancies. It has a high perinatal
morbidity and mortality if left untreated(1). In the recipient fetus
biventricular hypertrophy, atrio-ventricular valves regurgitation,
cardiomegaly, cardiac dysfunction and finally fetal hydrops may occur
all of them mainly due to hypervolemic status. Moreover, right
ventricular outflow obstruction (RVOTO), valvar pulmonary stenosis (PS)
and atresia and left ventricular hypertrophic cardiomyopathy may also be
presented. Donor twin on the other hand, usually shows little cardiac
pathologies on echocardiography(2-5). Different types of cardiac
abnormalities in TTTS can be explained by the altered fetal
hemodynamics(6). Fetoscopic laser photocoagulation (FLP) at 16-26 weeks
of gestation is the treatment of choice for TTTS. There are evidences of
normalization of cardiac function in fetuses with severe TTTS after FLP
Acquired structural cardiac anomalies are detected in a proportion of
treated pregnancies, as a consequence of the altered hemodynamics(7).
Due to increased rate of CHDs in TTTS, especially PS in recipient twin,
prenatal and postnatal echocardiographic assessment is needed (8).