Left pulmonary artery sling and congenital tracheal stenosis: to slide or not to slide?

The article published on Int J Clin Exp Med (1), raises very interesting issues regarding the surgical treatment of left pulmonary artery sling (LPAS) associated with congenital tracheal stenoses (CTS). CTS are rare anomalies characterized by the presence of complete cartilaginous rings along a variable length of trachea. In most cases, the complete rings extend for more than half of tracheal length. LPAS can be associated with CTS (the so-called ring-sling complex), with an incidence reported of about 50% of cases with CTS (2). Conversely, complete rings have been described in 50–65% of the patients with LPAS, as reported by old reports cited by the authors (3,4). This is the first issue for discussion, the real association of CTS in patients with LPAS. While ruling out a LPAS in a CTS patient is very simple with an angio CT scan, to be sure that a LPAS patient does not have any complete ring is more demanding. We cannot assume that the reported incidence of 50–65%, reported more than 30 and 40 years respectively (3,4), is correct. In those years, the diagnosis of CTS was probably based more on clinical symptoms than on bronchoscopy, so in our opinion this should be studied more precisely.