The images in these video clips illustrate the imaging technique used to determine cardiac position and sidedness, both in patients with normal anatomy and in those with complex male positions. Video 2.1A, 2.1D display the anatomy of the upper abdominal organs and great vessels. Normal abdominal sidedness is shown in the Video 2.1A, with the liver (L) positioned to the patient' right and the air artifact within the stomach seen on the left. Video 2.1C shows the anatomy of the same organs and vessels, but in a patient with situs inversus. The liver is to the patient's left, and the position of the aorta and IVC are reversed. To most easily determined cardiac position, Videos 2.1A, 2.1C, 2.1D is obtained in the imaging plane which is angled superiorly across the diaphragm until the cardiac structures come into view (Videos 2.1B, 2.1E, 2.1F). Video 2.1B is taken from a patient with normal cardiac anatomy. It shows the atria visualized near the midline, but with the left atrium (LA) posterior and slightly to the left of the right atrium (RA). The ventricles are to the left of the atrial structures with the apex of both ventricles being oriented inferiorly and to the left. These findings are consistent with normal cardiac position and orientation or situs solitus with levocardia. In contrast, the Video 2.1E l is taken from an examination of a patient with situs inversus totalis and dextrocardia. The atria are again found near the midline, but now the left atrium is posterior and slightly rightward. The ventricles are positioned inferiorly and to the right of the atria, with their apices oriented inferiorly into the right. This is the mirror image of the normal position and orientation, or situs inversus with dextrocardia. V LV, left ventricle; RV, right ventricle.