Although the atrial situs is identified on the basis of the morphology of the atrial appendage, characterization of the latter based on laterality is very difficult. The bronchial branching pattern is generally used to confirm the atrial situs because it almost always corresponds to the atrial situs. In right isomerism, bilateral atria have a triangular appendage with a wide opening characterizing the morphologic right atrial appendage, both main bronchi are symmetrically short, and the upper lobe bronchi are bilaterally eparterial. Another finding in right isomerism is juxtaposition of the IVC and the abdominal aorta Asplenia is frequently associated with right isomerism.