A right-sided aortic arch misdiagnosed as asthma since childhood

Congenital malformation of the aortic arch complex occurs in 3% of humans. These vascular aberrations result from embryonic structures that persist when there is incomplete atrophy or regression during normal development. Typically, anomalies of the aortic arch do not cause respiratory symptoms. However, in some individuals, the unusual position of the remnant vessels may compress the airway and cause airflow limitation. As might be expected, a symptomatic vascular anomaly is most often clinically apparent in childhood. We report an adult male with exertional dyspnea who had been diagnosed with asthma since childhood. After his symptoms proved refractory to newer asthmatic therapy, he was referred for further evaluation. Bronchial hyperactivity was not present with objective testing, and compression of his trachea by a right-sided aortic arch was confirmed with appropriate imaging studies. This report illustrates the need to confirm the diagnosis of asthma with objective measures of airflow and reminds the clinician that a congenital vascular aberrancy may initially elude diagnosis.