High incidence of progressive stenosis in aberrant left subclavian artery with right aortic arch

Right aortic arch with aberrant left subclavian artery (RAA/aLSCA) is a rare aortic arch anomaly. The clinical association of aLSCA stenosis with RAA/aLSCA has not yet been fully elucidated. The aim of this study was to investigate the diagnosis, incidence, management and outcome of aLSCA stenosis in infants with prenatally diagnosed RAA/aLSCA. Ten fetuses who were diagnosed as having RAA/aLSCA in Kyushu University Hospital between January 2011 and December 2014 were enrolled. The maternal and child medical records were reviewed to investigate sex, gestational age at the fetal diagnosis, gestational age and body weight at birth, the findings of computed tomography (CT), Doppler ultrasonography of the vertebral artery and angiography, and the complications and outcomes of aLSCA stenosis. In 8 of 10 patients, aLSCA stenosis was identified on the first CT examination after birth. No patients had dysphagia or respiratory distress. The stenosis spontaneously resolved in 3 patients. In 4 of the 5 remaining patients, aLSCA stenosis progressed, including one case in which complete occlusion occurred—the case was associated with retrograde flow from the left vertebral artery supplying the distal LSCA. Balloon angioplasty was successfully used to treat stenosis in two cases. The subclavian steal phenomenon and developmental problems were not observed in any patients. aLSCA stenosis was identified in 80% of patients with RAA/aLSCA after birth. The early detection and elective treatment of stenotic lesions may be required to prevent complete occlusion during the development of the cardiovascular and cerebrovascular systems.