**5. Conclusions**

The prenatal diagnosis of CHD in the last 30 years has reached a high degree of diagnostic accuracy allowing identification of almost all the main forms of CHD

during fetal life, in expert centers. In particular, prenatal diagnosis of conditions that constitute a neonatal emergency, such as duct dependent lesions, allows to manage the delivery in a tertiary care center. This strategy improves survival significantly, and reduces preoperative morbidity, and the risk of neurological compromise. While some CHD may have a successful surgical correction in postnatal life, a small selective subset of these defects can progress during intrauterine life and be susceptible to early interventions in the uterus. Fetal cardiac interventions might prevent in utero worsening from a simple, potentially correctable lesion to a complex cardiac condition in selective patients. FCIs are most commonly and successfully performed in the setting of 1) fetal aortic stenosis with risk for evolving to hypoplastic left heart syndrome, 2) HLHS with intact or restrictive atrial septum 3) pulmonary atresia/ stenosis with intact ventricular septum, with specific features associated with risk for worsening right ventricular hypoplasia. FCI also includes transplacental therapy, including maternal antiarrhythmic drugs in case of fetal arrhythmias and steroids. FCI is a procedure that has maternal and/or fetal risks, which must be well explained to parents at the time of counseling, to be sure that they fully understand the possible complications.

Moreover, fetal early diagnosis allows to program earlier clinical management and surgery after birth, improving outcomes. The improvement in the diagnosis and treatment of these conditions, due to extraordinary advances in imaging and cardiac surgical and interventional technologies in the last twenty years, has led to a significant increase in survival rate in patients with CHD, and accordingly, the number of patients with CHD who have reached adulthood has increased significantly and even surpass the number of affected kids.
