Prenatal Ultrasonic Diagnosis and Prognostic Analysis of Isolated Left Subclavian Artery (ILSCA) and Left Brachiocephalic Trunk (ILBCT) Malformation

The purpose of the study was to explore the prognosis, as well as antenatal ultrasonic features of isolated left subclavian artery (ILSCA) and isolated left brachiocephalic trunk (ILBCT) malformations, in order to improve prognosis and provide guidance for prenatal diagnosis. The origin and routing of cephalic and cervical vessels were observed in patients diagnosed with right aortic arch or right arterial duct arch in our hospital from March 2015 to March 2017, and the spectrum features related to ILSCA and ILBCT were analyzed. Fetuses diagnosed as ILSCA, or, and ILBCT were followed up for 3 months after birth. At the same time, a literature review was carried out for ILBCT and ILSCA in Pubmed. In our study, two cases with ILSCA and ILBCT were both diagnosed prenatally. They are not accompanied by other congenital malformations or chromosome abnormalities. No abnormality was found during postnatal follow-up except that left radial pulsation was weakened and blood pressure of the left upper limb decreased in baby with ILSCA. In baby with ILBCT, in addition to these abnormal changes, the left common carotid artery pulse disappearance too. In pubmed, three of 12 ILSCA or ILBCT did not have other congenital malformation or chromosome abnormalities. They were not diagnosed until the age of 3, 10, and 47 because of school exams or atypical symptoms, such as headaches, chest pain. Symptom of ILBCT or ILSCA without other abnormality is silent, and therefore they cannot be diagnosed timely after birth prenatal diagnosis is necessary for they can be treated in time.