Introduction
Accurate diagnosis of Aortic arch (AoA) anatomy is critical in the care of patients with congenital heart disease for planning cardiac surgery/intervention, diagnosing associated congenital heart defects (CHD), and evaluating possible compression of the esophagus or airway.1 Arch sidedness has been shown to influence the surgical incision, cardiopulmonary bypass cannulation, and interventional approach.2,3 Arch anomalies can increase the technical difficulty of endovascular treatment including carotid stent procedures and the risk of neurologic complications, and correct identification of arch anomalies helps avoid potential complications.4,5 Notably, patients with right aortic arch and mirror image branching have been reported to have additional CHD in up to 98% of cases.6
Determination of AoA sidedness is traditionally completed with echocardiography as being contralateral to the direction of the first brachiocephalic artery in suprasternal view.7 However, this method is challenged by poor acoustic windows, and can be technically difficult in small neonates for whom neck extension may not be feasible, the critically ill, or patients with aberrant subclavian artery. This method may also miss a double aortic arch (DAA). Given these challenges, the need for additional advanced imaging with CT or MRI for diagnosis has been reported in up to 28% of patients with AoA anomalies.8
In fetal echocardiography, imaging of the trachea is used routinely in the 3-vessel trachea view as a part of standard protocols to determine AoA sidedness and evaluate for AoA anomalies or pulmonary artery (PA) sling.9,10 In pediatric or adult echocardiography, however, tracheal imaging is not routine. Despite this, the tracheal rings can be identified with transthoracic echocardiography by the classic echogenic shadow they produce. While imaging the trachea in echocardiography is not novel, we have found no published literature about its use or feasibility. The objective of this study was to evaluate the feasibility of imaging the trachea with echocardiography and bring attention to this often-forgotten technique. We hypothesize that visualization of the trachea with echocardiography can be accomplished in most pediatric patients, and that the technique of a tracheal sweep can identify AoA sidedness or double aortic arch.