* Radiology department, Kasr Alainy hospitals, Cairo University, Egypt.
** Fetal medicine Unit, Cairo University, Egypt.
A 29-year old woman (G2P1) was referred at 38 weeks of gestation for routine antenatal care.
Despite the unfavorable fetal position and the advanced gestational age, ultrasound examination revealed
- Subtle ventricular disproportion (right heart dominance) with mild dilatation of main pulmonary artery compared to ascending aorta.
- Narrowing of the aortic arch isthmus with dilated tortuous ductus arteriosus. The aortic isthmus/ductus ratio appears less than 0.3.
- Distinct size discrepancy between the descending aorta and the distal transverse aortic arch and its isthmus.
- Normal forward systolic flow in the aortic arch without retrograde diastolic flow reversal
Our final diagnosis was coarctation of the aortic isthmus with hypoplasia of the distal transverse aortic arch.
A male baby (3050 g) was born with uneventful postnatal course and referred to a cardiothoracic surgeon for preparation of surgical intervention.
Normal systolic forward flow in the aortic arch with absent diastolic flow reversal confirmed, could exclude a ductal dependant systemic circulation and thus, postnatal prostaglandin infusion was not mandatory because forward flow will be maintained across different aortic arch segments but with a pressure overload exerted upon the left ventricle after closure of normal prenatal shunts (ductus arteriosus and foramen ovale) for which a planned surgical repair was the management of choice.
Images 1-6, videos 1-6: show subtle ventricular disproportion, isthmic narrowing with mild hypoplasia of distal transverse aortic arch on 2D, high definition color and power Doppler study in axial and sagittal planes.