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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 1, January/February 2016
AFRICA
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After establishing the diagnosis of a vascular ring by CTA,
echocardiography was used to exclude cardiac abnormalities.
The echocardiographer was usually able to comment on the
location and branching pattern of the aortic arch, but could not
visualise the vascular ring with certainty in most cases.
Bronchoscopy was not used routinely in the evaluation of
patients with vascular rings, except in the child with the impacted
coin, as is the usual practice at our institution when extracting
oesophageal foreign bodies.
All patients with complete rings were treated by surgical
division of the vascular ring, with the surgical approach guided
principally by the CTA. Factors determining the approach
included exposure of the vascular ring component to be divided,
the laterality of the ligamentum arteriosum and the patency
and calibre of all vascular structures as well as the trachea. Left
thoracotomy was used in six patients, right thoracotomy in one
patient and median sternotomy in one patient who underwent
concomitant ventricular septal defect closure.
The CTA provided an accurate representation of the findings
noted at surgery, and vascular ring division was completed
uneventfully in all cases. All eight patients demonstrated
symptomatic improvement post-operatively.
Discussion
Vascular rings account for approximately 1% of all congenital
cardiac anomalies, with the Edward’s classification being the
first to outline the embryological basis for the various aortic
arch anomalies resulting in a complete or partial vascular
ring.
1
A vascular ring may be composed of a combination
of patent vessels, atretic vascular segments or ligamentous
structures.
Table 1. Patient characteristics
Patient Age/gender Date Clinical features Chest radiograph
Contrast
oesophagogram CT angiography
Echocardiogram Surgery
1
2-month-
old boy
2008 Stridor
No tracheal stenosis Not done
Double aortic arch
Double aortic arch
seen
Right thoracotomy
Normal posterior
soft-tissue shadow
Trachea narrowing at
T3 level
Division of right
arch
Right aortic arch
2
9-month-
old girl
2009 Stridor
Right aortic arch Posterior indentation
of mid-oesophagus
at level of aortic arch
and impression on
right lateral wall
Double aortic arch
Double aortic arch
seen
Left thoracotomy
Respiratory
distress
Tracheal narrowing
at T4 level
Tracheal narrowing at
T4 level
Division of posterior
arch and ligamen-
tum arteriosum
Normal posterior
soft tissue shadow
3
24-month-
old girl
2010 Oesophageal
foreign body
Opacity right lower
lobe
Not done
Double aortic arch
Right aortic arch
seen
Left thoracotomy
Tracheal narrowing
at T4 level
Tracheal narrowing at
T4 level
Division of left
aortic arch
Right aortic arch
Normal posterior
soft-tissue shadow
4
9-month-
old boy
2011 Feeding diffi-
culty
Widened superior
mediastinu
Oblique indentation
of mid-oesophagus
at level of carina
Double aortic arch
Left aortic arch seen Left thoracotomy
Stridor
Tracheal narrowing
at T4 level
Tracheal narrowing at
T4 level
Division of anterior
aortic arch
5
7-month-
old boy
2011 Feeding diffi-
culty
Right aortic arch Posterior indentation
of mid-oesophagus
at level of carina and
impression laterally
on the right
Right aortic arch, aber-
rant left subclavian artery,
left ligamentum
Right aortic arch
seen
Left thoracotomy
Respiratory
distress
Tracheal narrowing
at T4 level
Tracheal narrowing at
T4 level
Division of ligamen-
tum arteriosum
Bilateral dysplastic
ribs
6
24-month-
old boy
2012 Respiratory
distress
Widened medias-
tinum
Posterior indentation
of mid-oesophagus
at level of aortic arch
Double aortic arch
Double aortic arch
seen
Left thoracotomy
Tracheal narrowing
at T3/T4 level
Focal tracheal narrowing
at T3 level
Division of left
aortic arch and liga-
mentum arteriosum
7
22-month-
old boy
2012 Congestive
cardiac failure
Right aortic arch Posterior indentation
of mid-oesophagus
at level of carina
Right aortic arch, aber-
rant left subclavian artery,
left ligamentum
PMO VSD with left-
to-right shunt
Median sternotomy
Respiratory
distress
Trachea normal
No tracheal narrowing Right aortic arch
seen
VSD closure and
division of ligamen-
tum arteriosum
Enlarged cardiac
silhouette with
plethoric lung fields
8
3-month-
old girl
2012 Wheeze
Trachea normal
Posterior indentation
of mid-oesophagus
at level of carina
Double aortic arch
Not done
Left thoracotomy
Chronic cough Normal posterior
soft-tissue shadow
Tracheal narrowing at T3/
T4 level
Division of atretic
aortic arch and liga-
mentum arteriosum
CT angiography: computed tomography angiography; PMO VSD: perimembranous outlet ventricular septal defect; T3: 3rd thoracic vertebra; T4: 4th thoracic vertebra.