Persistent left fifth aortic arch with pentalogy of Fallot

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

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.

Assessment of persistent fifth aortic arch by echocardiography and computed tomography angiography

To evaluate the utility of echocardiography (echo) in the diagnosis of persistent fifth aortic arch (PFAA), a very rare congenital aortic arch anomaly, and to compare echo and computed tomography angiography (CTA) imaging findings to improve our understanding of this anomaly.Data on the clinical diagnosis, imaging findings, and clinical management of PFAA were retrospectively analyzed in 10 suspected cases of PFAA admitted to our hospital between January 2012 and February 2017. We compared echo as a first line examination modality, and CTA and surgery results as the gold standard. Weinberg's classification was used to classify the type of PFAA.All patients (100%) received echo examination, eight patients (80%) received CTA examination, and four patients (40%) received sternotomy surgery; all recovered well after surgery. According to Weinberg's classification, 2, 6, and 2 cases (20%, 60%, and 20%) were classified as Type A, B, and C, respectively. Echo was able to diagnose 5 cases of PFAA (1 Type A case and 4 Type B cases) in the first instance. The diagnostic conformance rate of echo was 62.5% after comparisons with CTA and surgery results.The clinical manifestation of PFAA was atypical, and its diagnosis depended primarily on medical imaging. Echo has a relatively high diagnostic accuracy for PFAA, which is very valuable for its early detection.

Tetralogy of Fallot whit a "contralateral" ductus arteriosus

Two neonates were taken shortly after birth to our unit with a prenatal diagnosis of [S,D,S] Tetralogy of Fallot with pulmonary atresia and “unusual” aorta to pulmonary connection. The echocardiogram confirmed the main diagnosis showing: a left aortic arch with a vascular connection between the right innominate artery and the origin of the right pulmonary artery in patient A; and right aortic arch with a vascular connection between the left innominate artery and the origin of the left pulmonary artery in patient B. (www.actabiomedica.it)

[Persistence of the 5th aortic arch associated with interruption of the aortic arch]

We report a case of persistence of the 5th aortic arch associated with total interruption of the aortic arch. This clinical case shows the diagnostic pitfall of the persistence of the 5th aortic arch and its beneficial hemodynamic effect. Preoperative clinical picture was misleading, due to the persistence of femoral pulses and clinical signs of left-to-right shunt via a wide ductus arteriosus. The diagnosis was intraoperatively adjusted on the basis of blood pressure monitoring using catheter placed into the femoral artery.

How frequent is the fifth arch artery?

Although usually shown in embryology textbooks, the presence of the fifth pair of pharyngeal arch arteries has long been controversial. To the best of our knowledge, six pairs of bilaterally symmetrical arteries developing within the pharyngeal arches are yet to be found in any mammalian or avian species. Collateral channels between the distal ends of the fourth and sixth arch arteries, in contrast, have been found in up to half of all developing mouse embryos. In only one human embryo, again to the best of our knowledge, has a channel been found that extends from the aortic sac to the dorsal aorta, and hence qualifies as an arch artery. Despite these confounding factors in terms of the developmental heritage of the fifth arch arteries, the purported channels are invoked with increasing frequency to describe various lesions discovered in the setting of the congenitally malformed heart. Persistence of the artery of the fifth arch was initially proposed to explain double-barrelled aorta. It was subsequently proposed to account for various systemic-to-pulmonary channels feeding the pulmonary circulation in the setting of pulmonary atresia. It has also been claimed to persist so as to explain abnormal branching of the brachiocephalic arteries from the aortic arch. In the light of the ongoing doubts concerning the existence of the arteries of the fifth arch themselves, we have reviewed the various descriptions of purported fifth arch arteries within the world literature. We have then sought to validate the descriptions on the basis of our own understanding of development, for this purpose providing images of the remoulding arch arteries in the mouse so as to substantiate our conclusions. While accepting that our own interpretations are speculative, we suggest that more convincing alternative explanations can be advanced to account for the majority of lesions currently interpreted on the basis of persistence of the arteries of the fifth arches. Although the interpretations do not necessarily change the therapeutic approaches to the channels, appropriate description is important in terms of their classification.