CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 5, September/October 2011
268
AFRICA
Case Reports
Anomalous origin of the left pulmonary artery from the
ascending aorta in two children with pulmonary atresia,
subaortic ventricular septal defect and right-sided major
aorto-pulmonary collateral arteries
L PEPETA, FF TAKAWIRA, AM CILLIERS, PE ADAMS, NH NTSINJANA, BJ MITCHELL
Abstract
We report two rare cases of an anomalous origin of the left
pulmonary artery (AOLPA) from the ascending aorta, asso-
ciated with pulmonary atresia, a ventricular septal defect and
a left aortic arch. The cases are unusual because an AOLPA
is more commonly associated with a right aortic arch, and
it is more usual for the right pulmonary artery to originate
anomalously from the ascending aorta. The pulmonary
blood supply to the right lung in both patients was absent
and provided instead by major aorto-pulmonary collateral
arteries, which were stenosed at multiple levels. The AOLPA
in both patients originated from the postero-lateral aspect
of the ascending aorta just distal to the sino-tubular junc-
tion. Only one patient showed the more common association
of an unusual aortic arch branching pattern in the form
of an anomalous right subclavian artery. Neither patient
was in heart failure and the chest X-ray in both revealed
differential pulmonary perfusion with prominent vascular-
ity of the left lung. Cardiac catheterisation showed systemic
pressures within the anomalous left pulmonary artery.
Karyotyping revealed normal chromosomes, and fluorescent
in-situ hybridisation done in one patient was negative for
chromosome 22q11.2 microdeletion. Both patients have been
managed conservatively.
Keywords:
pulmonary atresia with ventricular septal defect,
anomalous origin of pulmonary artery, collateral arteries, pulmo-
nary hypertension, branchial arches, CATCH22 syndrome
Submitted 23/3/10, accepted 31/8/10
Published online 9/10/10
Cardiovasc J Afr
2011;
22
: 268–271
DOI: 10.5830/CVJA-2010-081
An anomalous origin of the pulmonary artery from the aorta
(AOPA) is very rare, with the first case of this nature reported by
Fraentzel in 1868.
1
The incidence of anomalous left pulmonary
artery from the aorta (AOLPA) has been reported in one study to
be around 17%,
1
with anomalous origin of the right pulmonary
artery (AORPA) from the ascending aorta as the more common
variant of AOPA, seen in about 83% of cases. Without surgery,
the mortality in patients with AOPA is extremely high, reach-
ing as high as 80%.
2-5
This is due to severe, rapidly progressive
pulmonary vascular disease and congestive cardiac failure. Both
isolated AOLPA and that associated with other defects have been
well described.
1,6,7
The commonest associated congenital cardiac lesion is tetral-
ogy of Fallot, which is seen in about 75% of cases.
1
AOLPA is
also associated with right arch of the aorta in 63% of cases, and
in about 38% of cases, an anomalous origin of the right subcla-
vian artery from the descending aorta has been reported as well.
1
Of note, both our cases had a left aortic arch and had no main and
right pulmonary arteries, with the only source of blood supply to
the right lung being partially stenosed major aorto-pulmonary
collateral arteries (MAPCAs). To the best of our knowledge, this
series represents the first report in the literature of the anomalous
origin of the left pulmonary artery arising from the aorta, associ-
ated with pulmonary atresia with no central pulmonary arteries
and MAPCAs supplying the whole of the right lung.
Case 1
This 10-month-old male patient was referred for assessment of
a complex cyanotic heart lesion and a centrally positioned heart,
namely, mesocardia. Clinical assessment showed the patient to
have central cyanosis, a loud single second heart sound, and one-
sixth ejection systolic murmur over the left upper parasternal
boarder. There were no abnormal facial features, no clubbing of
Division of Paediatric Cardiology, Department of Paediatrics
and Child Health, Dora Nginza Hospital, Port Elizabeth
Hospital Complex, Walter Sisulu University, Port Elizabeth,
South Africa
L PEPETA, FCPaed (SA),
Division of Paediatric Cardiology, Department of Paediatrics
and Child Health, Chris Hani-Baragwanath Hospital,
University of the Witwatersrand, Johannesburg, South Africa
AM CILLIERS, FCPaed (SA)
PE ADAMS, FCPaed (SA)
NH NTSINJANA, FCPaed (SA)
Division of Paediatric Cardiology, Department of Paediatrics
and Child Health, Pretoria Academic Hospital, University of
Pretoria, Pretoria, South Africa
FF TAKAWIRA, FCPaed (SA)
BJ MITCHELL, FCPaed (SA)
