CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 5, September/October 2011
AFRICA
269
the digits or features of heart failure. The chest X-ray showed
a cardiothoracic index of 66%, mesocardia, a left-sided aortic
arch, a boot-shaped heart with right ventricular predominance
and an absent pulmonary artery segment. Differential perfusion
to the lungs was evident on the chest X-ray, showing prominent
pulmonary vasculature on the left and reduced pulmonary vascu-
lature on the right. Situs solitus was present (Fig.1).
The electrocardiogram revealed right-axis deviation and right
ventricular hypertrophy by voltage criteria. An echocardiograph-
ic assessment confirmed the presence of pulmonary atresia with
a large mal-aligned peri-membranous (sub-aortic) ventricular
septal defect, and an overriding aorta. A surprising finding was
the anomalous origin of the left pulmonary artery from the left
postero-lateral aspect of the ascending aorta just above the sino-
tubular junction, and an aberrant right subclavian artery arising
from the descending aorta, distal to the left subclavian artery.
In addition, numerous major aorto-pulmonary collateral vessels
were seen arising from the descending aorta, and the ascending
aorta arched to the left (Fig. 2). The central pulmonary arteries
were not visualised.
Angiography confirmed the above findings (Figs 3, 4). Of
importance were the total absence of native pulmonary arterial
vasculature and the presence of a bipartite right ventricle with
an absent apical portion. Haemodynamic studies revealed very
low systemic saturations of 79%, and as was expected, very
high systolic pressures equalling that of the aortic pressures of
61 mmHg in the aberrant left pulmonary artery. By contrast, the
pressures measured within the major aorto-pulmonary collateral
Fig. 1. Chest roentgenogram showing a boot-shaped
heart, differential perfusion, with increased perfusion to
the left lung and reduced perfusion to the right lung.
Fig. 2. Two-dimensional echocardiographic study with
colour flow imaging showing the anomalous origin of the
left pulmonary artery arising from the proximal ascend-
ing aorta.
Fig. 3. Ascending aortogram in antero-posterior view
showing a left aortic arch and the anomalous left pulmo-
nary artery arising from the proximal ascending aorta.
Fig. 4. Descending aortogram in antero-posterior view
showing the aberrant right subclavian artery arising from
the descending aorta distal to the left subclavian artery.
The major aorto-pulmonary collateral vessels to the right
lung can also be seen.
