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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 26, No 4, July/August 2015
e8
AFRICA
From on the above findings, for this patient, a diagnosis in
keeping with a conotruncal anomaly could best be classified
as type 1, based on Collette and Edwards’ classification.
2
Furthermore, the thoracic vasculature was significantly altered,
with irreversible pulmonary hypertension. Taking this into
account, conservative management was recommended.
The patient appeared to make good progress on medical
treatment, which included bed rest and fluid restriction. She
was advised against pregnancy, considering her mature age
and in light of the underlying severe pulmonary hypertension.
Her condition appeared to have remained stable 15 months
after discharge from hospital. Chromosomal studies were not
undertaken, however her child appeared in a good state of
health.
Discussion
PTA usually includes a large VSD with the presence of a
significant left-to-right shunt, and is dependent on the resistance
ratios between the systemic and pulmonary circulation. Indeed,
pulmonary vascular resistance (PVR) decreases during the
first weeks of life, and neonates experience congestive heart
failure because of the increased pulmonary blood flow, unless
the pulmonary arteries are hypoplastic or stenosed or there
is persistently elevated PVR. These factors may delay the
appearance of symptoms and babies appear mildly cyanosed due
to the high PVR.
According to Marcelletti
et al.
,
3
these first effects are mainly
beneficial and some patients unusually survived through to
adulthood. Such survival is achieved only at the price of
subjecting the pulmonary vasculature to the effects of severe
pulmonary hypertension due to occlusive intimal fibro-elastosis.
3
Echocardiography is a reliable, non-invasive, first-line imaging
tool that proved to be beneficial in the diagnosis of differentiating
this lesion from pulmonary atresia with VSD. The hallmark of
PTA is that only a single semilunar valve is seen.
4
MRI, although expensive and not easily accessible to all
patients, is a complementary modality that has been shown
to be accurate in the diagnosis and follow up of CHD.
5
It is a
useful adjunct, currently recognised by paediatric cardiologists
and cardiac surgeons because it includes a wide field of view
and multiplanar capabilities and reconstructions. The strength
of MRI includes comprehensive access and coverage, providing
imaging of all parts of the right ventricle, pulmonary arteries,
pulmonary veins and aorta.
6
Our case illustrates the major role of cardiac MRI, due to it
being a fairly safe technique that allows precise definition and
high resolution, and in this case, it demonstrated the complex
anatomy of PTA. In this patient, the truncal valve was trileaflet
and competent, which may have played an important role in her
survival, since it is well established that truncal valve insufficiency
is associated with higher rates of early and late mortality.
7
Eisenmenger physiology is an absolute contraindication to
pregnancy. Maternal mortality is reported to be as high as
36%.
8
However, in this case, the patient had not received prior
counselling before she fell pregnant, since her diagnosis was
made three years after delivery. She was fortunate not to have
had a complicated pregnancy.
Conclusion
Echocardiography and MRI played an important role in
detecting the PTA in this patient, which assisted in appropriate
management. PTA is an uncommon cardiovascular anomaly
with a poor prognosis, and without surgical repair, is regarded
to be incompatible with life. This unique case study (type 1
PTA) offers an example of the natural history of an unrepaired
complex congenital cardiac disease that overcame the odds of a
short life expectancy.
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