Congenital heart diseases (CHD) are one of the most frequent congenital malformation. Prenatal detection of critical CHD allows planning and decision making and has a great impact on pre and postoperative status of the newborn. Most CHD do not have hemodynamic repercussion in-uterus, being the safest way of referral and avoiding transport of critically ill babies. Prenatal detection of a fetus with Left Ventricular Hypoplasia Syndrome forces a close follow up and management of associated conditions that affect the fetal hemodynamics: arrythmias, tricuspid insufficiency, right ventricular disfunction, restricted Foramen Ovale (FO), other cardiac malformations, growth restriction, extracardiac malformation, etc. These associations determine prenatal and postnatal prognosis, survival, and the need for in-uterus or immediate postnatal treatment and intervention. Prematurity and low weight at birth increase morbimortality. Management of arrythmias and heart failure might prevent premature birth. Restriction of the FO determinates the level of complexity and requirements of the place of birth. Doppler of the pulmonary veins has the best correlation with the need of immediate postnatal intervention and allows a stratification of the risk of restriction of the FO. Critical restriction of the FO might require in-uterus intervention. Critical CHD need a multidisciplinary assessment and follow up and requires, above all, family and social support.

M Fernanda Biancolini is a pediatric and fetal cardiologist. She is the head of the fetal echocardiography laboratory at Pedro de Elizalde children’s hospital in Argentina. She is also a member of the national CHD network. She is a teacher at the fetal and pediatric cardiology postgraduate course at the University of Buenos Aires. She dictated several courses for pediatric cardiologist and sonographers dedicated to fetal heart scan. She is the scientific secretary of the Pediatric Cardiology and Adult Congenital Heart Disease Council at the Argentinian Society of Cardiology. She has multiple publications in indexed journals, participated in the Adult Congenital Heart Disease Consensus for the Argentinian Society of Cardiology (SAC) and wrote the chapter of Fetal Echocardiography at the recently published book from the Interamerican Society of Cardiology (SISIAC).