A Phantom Case of Coarctation of the Aorta

A 9-month–old infant girl was referred for management of transverse aortic arch hypoplasia in the setting of a right arch with mirror-image branching of the brachiocephalic vessels and an aberrant left subclavian artery originating from the descending aorta. Because she was asymptomatic and without left ventricular hypertrophy on echocardiogram, no interventions were undertaken. At multiple subsequent clinic visits through 4 years of age, extremity pulses and blood pressures continued to be normal and equal despite persistent arch hypoplasia and Doppler evidence of arch obstruction on serial echocardiograms.At 4.5 years of age, her left radial pulse was noted to be relatively weaker for the first time, but 4-extremity blood pressures remained equal. An echocardiogram with Doppler revealed a continuous systolic-diastolic forward flow waveform in the abdominal aorta. One year later, her left radial pulse remained relatively weak, and her right leg systolic blood pressure was 30 mm Hg lower than that in her upper extremities. These findings prompted magnetic resonance angiography, which revealed a complex form of right aortic arch with moderate transverse aortic arch hypoplasia measuring 6 mm in diameter, narrowing to 4 mm at the isthmus. Distal to the coarctation, the proximal descending aorta was 11 mm in diameter. Both common carotid arteries arose proximal to the hypoplastic transverse aortic arch. There were no significant aortic-intercostal collateral arteries (Figure 1 and online-only Data Supplement Movie I).Figure 1. Three-dimensional (3D) reconstruction of …