Association of chromosome 22q11 deletion with isolated anomalies of aorticarch laterality and branching

OBJECTIVES The purpose of this study was to determine the frequency of chro mosome 22q11 deletions in patients with isolated anomalies of the aortic ar ch and its branches. BACKGROUND Chromosome 22q11 deletions are often present in patients with ce rtain forms of congenital cardiovascular disease, including tetralogy of Fa llot, truncus arteriosus and interruption of the aortic arch. Among patient s with these anomalies, chromosome 22q11 deletion is more common in those w ith abnormal aortic arch laterality or branching. METHODS We studied 66 patients with isolated anomalies of the aortic arch a nd no associated intracardiac defects for deletions within chromosome 22q11 , using fluorescence in situ hybridization with the cosmid probe N25 (D22S7 5). Arch anomalies included: double aortic arch (n = 22); right aortic arch with aberrant left subclavian artery (n = 28); right aortic arch with mirr or-image branching and a vascular ring formed by a left-sided ductus from t he descending aorta (n = 5); right aortic arch with mirror-image branching and no vascular ring (n = 4); and left aortic arch with aberrant right subc lavian artery (n = 7). In addition, four patients had a cervical aortic arc h, four had aortic coarctation and six had hypoplasia/atresia of the proxim al pulmonary arteries. RESULTS Chromosome 22q11 deletions were found in 16 patients (24%) across t he full spectrum of anomalies studied. Among the morphologic variables anal yzed, only hypoplasia/atresia of the proximal pulmonary arteries correlated with the deletion (p = 0.03). Among patients with a double arch, the frequ ency of chromosome 22q11 deletion was higher in those with an atretic minor arch than it was in those with a patent minor arch (p = 0.02). CONCLUSIONS Chromosome 22q11 deletion is associated with isolated anomalies of laterality or branching of the aortic arch in 24% of cases in our serie s. These findings should alert the clinician to consider deletion screening in patients with isolated anomalies of the aortic arch. (J Am COll Cardiol 2001;37:2114-9) (C) 2001 by the American College of Cardiology.