Two-dimensional echocardiographic recognition of the right aortic arch

A mirror-image right aortic arch (RAA) is frequently associated with congenital heart disease. The chest roentgenogram with or without contrast remains the noninvasive diagnostic method of choice. While 2-dimensional (2-D) echocardiography has been used to elucidate the left aortic arch (LAA), detailed description of the technique for RAA has not been reported. This study was pursued to delineate the 2-D echocardiographic approach to the patient with RAA. Twenty-seven patients in this study had LAA (Group A) and 27 had RAA (Group B). The 2-D echocardiographic examinations concentrated on the standard suprasternal long-axis (SSNL), parasternal long and short axes, and the subcostal abdominal short-axis views. When the SSNL failed to demonstrate LAA, an alternate position for RAA was utilized. The SSNL correctly identified the LAA in all Group A patients, but in Group B it located only the ascending aorta. This simulated an interrupted aortic arch anomaly. Transducer realignment to position 2 confirmed RAA in all Group B patients. In the parasternal axes, the left descending aorta was detected posterior to the atrioventricular groove or the left ventricle in every Group A patient but in no Group B patient. The descending aorta was found to the left of the spine on the abdominal short-axis view in both groups. The 2-D echocardiographic technique proposed for RAA is simple, rapid, and definitive. It should be pursued whenever LAA cannot be demonstrated, especially in children suspected of having a congenital heart defect. Anticipation of RAA can expedite chest and cardiovascular surgery.