Abnormalities of Cardiac Situs and Heart Disease Diagnosed by Echocardiography in Patients with Biliary Atresia

Abstract

Biliary atresia (BA) occurs in 1:8000 to 1:23 000 live births, being responsible for over 50% of liver transplantations in children. [1][2][3] Among these patients, 7% to 12% have situs abnormalities known as left isomerism (LI) or polysplenia syndrome. 4,5 Similarly, 31% to 50% of all patients with LI have BA. 1,6 The essential characteristic of LI is the unusual laterality and symmetry of the thoracic and abdominal viscera. In LI, left-sided structures are usually replicated (replacing the corresponding morphologically correct structures). [7][8][9] Characteristic findings are: double left atrium, double left lung and left main bronchus; descending aorta positioned anterior to the spine (slightly to the right or to the left); stomach usually positioned to the right; transverse liver; polysplenia. 2,3,4 Regarding situs abnormalities, special interest is given to the identification of the atrial situs, which is a significant factor in the association with several heart diseases. According to the principle of thoracoabdominal compliance, atrial situs may be inferred from an echocardiography assessing the