Persistent fifth aortic arch: a single-center experience, case series

Abstract

Background: Persistent fifth aortic arch (PFAA) is an extremely rare congenital cardiovascular malformation and there is limited data in the literature. The objective of this study is to enhance our understanding and diagnosis of PFAA from echocardiography and computed tomography angiography (CTA) findings, and to evaluate the application of echocardiography in the diagnosis of PFAA.

Methods: We retrospectively reviewed five cases of PFAA diagnosed from October 2016 to September 2019 at the Affiliated Children's Hospital of Capital Institute of Pediatrics. We described their diagnosis by echocardiography and CTA findings, and medical history.

Results: Five cases of PFAA were identified in the study. Patients aged from 3 to 48 months and weighed from 4 to 12 kg presented different clinical symptoms upon clinical examination. All the patients completed a primary echocardiographic assessment; however, the first two patients were misdiagnosed by echocardiography and was confirmed by supplemental CTA while the other three patients were directly diagnosed by echocardiography. Surgery was necessary for three patients, two of whom accepted and one refused. The other two patients only needed a follow-up assessment, which showed good results.

Conclusions: The clinical manifestation of PFAA in our patient population was atypical, and their diagnosis depended on the use of echocardiography. In the case of uncertainty, the final diagnosis was confirmed by CTA. Although the nomenclature and embryonic origin of PFAA remains controversial, the accurate diagnosis of aortic arch abnormalities and associated malformations are imperative for time-sensitive treatments.

Keywords: Persistent fifth aortic arch (PFAA); case series; computed tomography angiography (CTA); echocardiography; surgery.

Figure 1

Images of Case 1 in echocardiography, CTA, and surgery. (A) Color Doppler showed the 4^th aortic arch unconnected to the descending aorta and stenosis of the 5^th aortic arch; (B,C) CTA images demonstrated an interruption 4^th aortic arch and a stenotic 5^th aortic arch; (D) images in the operation confirmed the structures of the 4^th and 5^th aortic arch. CTA, computed tomography angiography; LPB, left principal bronchus.

Figure 2

Images of Case 2 in echocardiography, CTA, and surgery. (A) Two-dimension echocardiography showed the shape of the 5^th aortic arch; (B) CTA images demonstrated an interruption 4^th aortic arch and a stenotic 5^th aortic arch; (C) images in the operation showed the remnant of the 4^th aortic arch and 5^th arch. CTA, computed tomography angiography.

Figure 3

Images of Cases 4 and 5 in echocardiography. (A) Echocardiography demonstrated an interruption 4^th aortic arch and unobstructed 5^th aortic arch in Case 4; (B,C,D) echocardiography images showed an interruption 4^th aortic arch and fluent 5^th arch with small size PDA in Case 5. PDA, patent ductus arteriosus.