Double Aortic Arch

Vascular rings account for <1% of cardiovascular malformations that require surgical correction. Double aortic arch is the most common form of complete ring that encircles both the trachea and the esophagus.

Race/gender predilection: None.

Recurrent respiratory infections often aggravate chronic airway obstruction.

Baseline dynamic tracheal compression can progress to complete airway obstruction upon induction and muscle relaxation.

Persistent postop airway obstruction requiring prolonged mechanical ventilation and CPAP.

Esophageal obstruction: Dysphagia, choking, emesis, aspiration, FTT.

Tracheal obstruction: Chronic cough, wheezing, barky-brassy cry, inspiratory/expiratory stridor; acute episodes of severe respiratory distress, apnea, cyanosis, and ALTE.

Associated cardiac anomalies (10–20%): VSD, ASD, interrupted aortic arch, transposition of the great arteries, tetralogy of Fallot, truncus arteriosus, and complex univentricular lesions.

Chromosome 22q11 deletion syndrome (20%): Genetic defect associated with syndromes, such as DiGeorge, velocardiofacial, CHARGE, and VACTERL; features include endocrine abnormalities (hypocalcemia, thyroid/parathyroid dysfunction, short stature), palatal and laryngotracheal abnormalities, developmental delay/neurologic abnormalities, renal tract malformations, thrombocytopenia, T-cell deficiencies, and autoimmune disorders.

Vascular rings can be classified as complete or incomplete. Double aortic arch is the most common form of complete ring that encircles and compresses both the trachea and esophagus.

Symptoms usually occur at birth or within the first 3 mo of life. The degree of tracheal and esophageal compression will dictate the severity of respiratory and GI perturbation.

Initial work-up with CXR and upper GI can reveal tracheal deviation/narrowing and proximal esophageal distention/indentation. After the diagnosis is suspected, ECHO is used to examine arch anatomy and rule out other intracardiac anomalies. Both MRI and CT are very useful in further delineating vascular, airway, and GI anatomy. Cath is now reserved for assessing complex cardiac defects that require additional hemodynamic information. Bronchoscopy is often performed at the time of repair to evaluate the location, degree, and extent of airway obstruction, which may help to identify those pts at risk for postop respiratory compromise.

During normal human development, six branchial arches are sequentially formed and penetrated by six paired aortic arches that arise from the aortic sac and terminate in paired DA. These primitive arches largely regress (the fourth and sixth being the most persistent) and by the eighth week, the right DA largely involutes and forms the distal part of the right subclavian artery, leaving only the left DA to form the distal aortic arch and descending aorta. Failure of the right DA to involute results in a double aortic arch, whereby the ascending aortic arch divides into two arches, passes on each side of the trachea and esophagus, and joins posteriorly to form the descending aorta. The right carotid and subclavian arteries arise from the usually dominant, posterior right arch, whereas the left carotid and subclavian arteries arise from the smaller, anterior left arch.