Ultrasonographic clues and methods for fetal anomalies of the aortic arch

Objective To study the ultrasonographic clues and methods for fetal anomalies of the aorta arch and improve prenatal detection of anomalies of the aorta arch.Methods One thousand four hundred and seventy-two cases fetus who were carried out detailed scan and whose results were confirmed were chose as study objects.Every routine fetal echocardiography included four chamber and left and right outflow tract and three-vessel trachea view(3VT).The more views which included longitudinal and coronary view of the aorta arch and coronary view of the trachea and main bronchus were obtained when the abnormality of aorta arch was suspected.Results One hundred and forty-eight cases with anomalies of aorta arch were diagnosed by ultrasonography.One case was misdiagnosed.Ninety-two fetus with anomalies of aorta arch which included 28 aortic coarctation(CoA) and 10 interrupted aortic arch (IAA) and 52 right-side aortic arch and abnormal aortic branch and 2 double aortic arch were confirmed by postmortem or postnatal echocardiography and surgery.Of the 92 confirmed cases,24 had prenatally diagnosed additional complex intracardiac anomalies.All cases with CoA and IAA presented ventricular and/or great arterial disproportion with smaller left ventricle and aorta diameter on four chamber view and 3VT.Right aortic arch (RAA) and abnormal aortic branch(AAB) displayed aortic arch located on the right side of the trachea and increased distance between the aortic arch and arterial duct and abnormal aortic arch branch-subclavian artery originating from the beginning section of the descend aorta which coursed behind the trachea with U-shaped appearance on the 3VT plane.The display rate of the transverse and longitudinal and coronary view of the aorta arch was 98.4%,90.0%,81.9%,respectively.Conclusions Disproportional ventricular and /or great arterial with smaller left ventricle and aorta diameter are the clues for CoA and IAA.Increased distance between the aortic arch and arterial duct is the clue for RSA.The transverse view of the aortic arch 3VT is the most sensitive for detecting the anomalies of the aortic arch and the most easily be obtained.The longitudinal and coronary view of the aorta arch and coronary view of the trachea and main bronchus are helpful in differentiating the anomalies of the aortic arch. Key words: Ultrasonography,prenatal; Heart defects,congenital; Aortic arch anomaly