CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 3, April 2012
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AFRICA
in females. The double autograft, also considered in poor settings
due to shortage of homographs, needs high levels of surgical
skill and increases the operative risk.
Congenital heart disease
There is a large underserved population of children with
congenital heart disease in Africa, since most paediatric services
are oriented to the diagnosis and management of endemic
infectious diseases, and there is a shortage of trained personnel
capable of diagnosing congenital heart defects, resulting in late
diagnosis, usually in the presence of heart failure, pulmonary
hypertension and severe polycythaemia. The number of facilities
for cardiac surgery is also small and, as a result, there is a wide
range of native abnormalities.
10
Malformations ranked as the second most common form of
heart disease, with a frequency of 26% among black patients
of all ages in hospital-based studies, which also revealed that
congenital cardiac defects were the dominant conditions rather
than rheumatic or other acquired heart diseases.
10
In this study,
the mean age at referral to a paediatric cardiologist was high and
a pattern of late presentation was found with under-representation
of lesions that have a high mortality in infancy, suggesting that
a significant number of patients miss the opportunity to have
optimal surgical intervention.
Several paediatric hospital series show the importance of CHD
in Africa. These conditions ranked first, with a frequency of 53%
in a series from South Africa that considered only children aged
15 years or under,
11
and are responsible for one-quarter of the
cases of heart failure in Ibadan.
12
The predominant lesions are
ventricular septal defect, tetralogy of Fallot and patent ductus
arteriosus.
10,11
In Africa, surgery for CHD is frequently performed in
adults or adolescents, in whom the operative risks are increased
and related to myocardial fibrosis and irreversible pulmonary
changes. The main reasons for late surgery are late diagnosis,
time delay between the diagnosis and actual surgery, loss to
follow up, and refusal of surgery earlier in life.
The choice between complete repair and two-stage ‘palliative
+ corrective’ procedures in underdeveloped countries may be
influenced by socio-economic factors affecting the physical
condition of the patient. Palliation by pulmonary artery
banding, atrial septectomy or a systemic–pulmonary shunt is
still preferable in those conditions in which total correction
in infancy carries a high risk or is not feasible. On the other
hand, palliative procedures may constitute a way of selecting
those patients in whom eventual complete correction would
be justified.
13
However, if inadequately performed, pulmonary
artery band and systemic–pulmonary shunt may adversely affect
outcome and demand further aggressive management prior to
definitive repair.
14
Endomyocardial fibrosis
EMF is a disease of unknown aetiology, characterised by fibrosis
and thickening of the mural endocardium and valvular apparatus,
causing restriction to ventricular filling and severe atrio-
ventricular valve dysfunction. The disease has several forms and
can be classified haemodynamically as predominantly restrictive
when it affects mainly the mural endocardium, predominantly
valvular when the subvalvular apparatus is severely affected,
or mixed when both restrictive and valvular lesions are present.
There is no effective treatment for EMF. Surgery is indicated for
patients in NYHA class III/IV but is technically very demanding
and has been associated with high morbidity and mortality,
especially when predominantly murally affected.
The initially described Dubost technique
15
has been evolving to
reduce the complications associated with valve replacement and
radical endocardectomy, mostly low-cardiac output syndrome
and complete atrio-ventricular block. An atrial approach is
the most frequently used but offers poor visualisation of the
apex and lateral wall of the left ventricle. Therefore apical
ventriculotomy or a transaortic–transatrial approach may be
needed when complete endocardial resection is required in those
regions.
16
The post-operative period demands intensive-care
management in patients with poor nutritional status and long-
standing heart failure. The early mortality was initially around
20% but has now been reduced to 10%.
17-19
This is mainly
caused by incapacity to wean from cardiopulmonary bypass,
low-cardiac output syndrome, cerebral embolism, arrhythmias,
renal failure and pulmonary embolism.
17,20,21
In the immediate
post-operative period, re-interventions may be needed as a rescue
procedure in patients with right heart failure and low-cardiac
output syndrome, to relieve persistent pericardial effusion with
repetitive tamponade and to implant partial cavo–pulmonary
shunts.
22,23
Most patients have dramatic clinical improvement
with regression of ascitis and congestive failure, as well as
improvement in quality of life, although the ultimate prognosis
is probably not altered.
24
However, mortality remains high during
the first two post-operative years, reaching 13%.
20
Good long-term results may be obtained with early diagnosis
and timely intervention before shrinkage of the ventricle occurs.
Promising results have been obtained in terms of restoration of
both structural and functional changes, with better understanding
of the pathophysiology and the use of a new tailored approach
for relief of right ventricular cavity obliteration.
25
Although there
was no evidence of recurrence over a short follow-up period,
further research and longer follow up is needed, since recurrence
of endocardial fibrosis has been reported in a Brazilian series.
26
The challenges for sub-Saharan Africa
The African paediatric population is extremely underserved
by paediatricians in general and by paediatric cardiologists in
particular, most working in the major referral units in urban
areas. Families have therefore to travel long distances in
search of medical care for their children with heart disease.
The state-run health infrastructures are mostly directed at
prevention and treatment of the major endemic diseases, such
as malaria, tuberculosis, leprosy, HIV/AIDS, parasitic infections
and diarrhoeal diseases.
Due to lack of financial and human resources, both
interventional cardiology and open-heart surgery have been
introduced in Mozambique, Kenya, Sudan, Ethiopia, Senegal
and Nigeria through collaboration programmes between local
institutions and non-governmental organisations from Europe
and North America.
Comprehensive paediatric cardiovascular services are needed
in Africa. These should include research aimed at understanding
the mechanisms underlying conditions geographically restricted
