Cardiac evaluation of a child with stridor

Abstract

Abstract This is the case of a 6-month-old boy who is diagnosed with, and treated for, a vascular ring, following several admissions to paediatric intensive care with difficult respiratory symptoms and ongoing failure to thrive. This case highlights the diagnostic challenge presented by these patients. Cardiovascular causes of paediatric airway compression are often under-recognized, with consequent delay in diagnosis. Although they are much less common than other causes of stridor, such as laryngomalacia or other tracheo-bronchial anomalies, chronic airway compression in childhood from vascular malformations carries significant morbidity and mortality. It is readily treatable and should not be overlooked. A high index of suspicion for mechanical compression should be maintained in small children with recurrent obstructive respiratory signs and symptoms or the older child presenting with dysphagia. The most prevalent vascular anomalies resulting in airway compression are a double aortic arch, right aortic arch with an aberrant left subclavian artery, innominate artery compression, left aortic arch with an aberrant right subclavian artery (rarely), and pulmonary artery sling. Rarely, complex congenital heart disease, itself leading to dilatation of the cardiac structures, may precipitate airway compromise, as in tetralogy of Fallot with an absent pulmonary valve syndrome or conditions with significant atrioventricular valve regurgitation causing left atrial enlargement. A dilated ascending aorta may compress the trachea, producing similar symptoms likewise with a cervical aortic arch with an aberrant sublclavian artery and ipsilateral ligamentum arteriosus. Such cases require a comprehensive diagnostic workup. Investigations include plain chest X-ray, echocardiogram, direct microlaryngoscopy and bronchoscopy, and CT angiography or cardiac MRI. A normal laryngoscopic examination should warrant further investigation in the presence of ongoing symptoms. An appreciation of aortic arch embryology is important in interpreting echocardiography and cross-sectional imaging in relation to the role of airway compression. Management often necessitates multidisciplinary collaboration among specialties, including ear, nose, and throat (ENT) specialists, paediatric cardiologists, respiratory physicians, intensivists, and cardiothoracic surgeons. Definitive treatment depends on the underlying pathology but usually involves surgical decompression or aortopexy. A proportion of patients will continue to exhibit symptoms following surgical release, due to ongoing weakness of the airway, and in severe cases may require ongoing respiratory support.