IJCS | Volume 33, Nº1, January / February 2019

DOI: 10.5935/2359-4802.20190045 102 CASE REPORT International Journal of Cardiovascular Sciences. 2020;33(1):102-106 Mailing Address: Cesar Cilento Ponce Av. Conselheiro Nébias, 53. Postal Code: 11045-002, Encruzilhada, Santos, São Paulo, SP – Brazil. E-mail: cesarcponce@gmail.com Complete Interruption of Aortic Arch and Non-Immune Hydrops Fetalis: A Case Report with Autopsy Cesar Cilento Ponc e Universidade Metropolitana de Santos (UNIMES), Santos, São Paulo, SP – Brazil Manuscript received on August 08, 2018, revised manuscript on November 14, 2018, accepted on January 02, 2019. Vascular Ring; Aorta/abnormalities; Aorta/surgery; Aortic Coarctation; Ductus Arteriosus; Perinatal Mortality; Autopsy. Keywords Introduction Interrupted aortic arch (IAA) occurs in three births per million, and accounts for approximately 1%of congenital heart diseases (CHDs). 1-3 The first case reported with these anomalies appears to be the one by Seidel in 1818. 1 IAA is a severe form of CHD characterized by a lack of luminal continuity between the ascending and the descending thoracic aorta. 4 The two most common associated cardiac anomalies are ventricular septal defect (90%) and patent ductus arteriosus (98%). 4 Isolated IAA is very uncommon 2,4 and it is considered incompatible with life. 3 To understand the pathogenesis of IAA, we must remember the embryological development of the main vessels. At approximately the third week of embryonic life, two aortas, a dorsal and a ventral, are connected by six paired arterial branches (aortic arches). In the course of development, a series of changes occur leading to the disappearance of several aortic arches, beginning with the first, the second and the fifth pairs. The third pair of arches persists to form the common carotid and external carotid arteries, and the fourth arches persist to form the permanent arch of the aorta on the left side and the proximal segment of the subclavian artery on the right side. The proximal portions of the sixth arches become the pulmonary arteries. On the right side, the distal segment disappears, while on the left the corresponding distal segment remains as the ductus arteriosus. 1 In IAA, there is a failure of development of the fourth left aortic arch, the pulmonary artery that transports the blood from the heart to the descending aorta via the ductus arteriosus. This absence of the aortic isthmus causes a discontinuity between the ascending and descending aorta. 5 Symptoms usually occur early in the neonatal period and clinical deterioration is often rapid. The median age at death in untreated IAA with associated cardiac anomalies is 10 days. 2 In the embryo, the superior vena cava returns venous blood from the upper body. This less oxygenated blood leaves the heart via the pulmonary artery. A small amount reaches the lungs while the rest goes into the descending aorta through the ductus arteriosus. The umbilical vein transports oxygenated blood to the right auricle via the hepatic veins, ductus venosus and inferior vena cava; the main part flows through the ventricular septal defect into the left side of the heart, 2 and from there it is distributed to the head and arms. 1,2 In this type of circulation, in case of complete loss of continuity between the ascending and descending aorta it is important the re-establishment of a communication that allows the oxygenated blood that reaches the left heart passes into the right side for adequate supply of the lower portion of body. 2 The absence of a septal defect and a patent ductus arteriosus is incompatible with extra-uterine life. Prenatal diagnosis of IAA has been reported in few case series. 6 The prenatal characterization of different IAA types based on echocardiographic examination has some limitations. 6 The clinician’s knowledge of embryology and anatomy of the great vessels is essential for the diagnosis of IAA. The aim of this study was to draw attention for possible cardiac abnormalities in hydropsy fetus and to report a case of fetal death by IAA with autopsy.