CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 4, May 2013
AFRICA
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on cause.
11
Accordingly, age distribution is expected to vary
between countries and centres.
The 1.4:1 male-to-female ratio recorded in the present study
is comparable to the 1.5:1 for Nigeria,
2
suggesting relative
uniformity in gender-related factors affecting the distribution of
congestive heart failure in a Kenyan paediatric population.
Infection was the leading cause of heart failure, followed by
anaemia, and rheumatic and congenital heart diseases. This is at
variance with literature reports from developed countries where
most causes are congenital heart disease and cardiomyopathy.
1,3
It
however resembles results from Ibadan in Nigeria.
12
Several other
studies support variations in the leading causes of heart failure
in children between developed and developing countries (Table
2). These variations may be due to differences in awareness of
preventive measures and access to healthcare services.
The infections most frequently associated with cardiac
failure were pneumonia, upper respiratory and throat infections.
This is concordant with reports from African countries where
respiratory infection constitutes a significant cause of heart
failure.
12
Interestingly, the situation observed here resembles that
which was obtained in the United Kingdom in the middle of the
last century, when bronchitis, pneumonia and other respiratory
infections were the most frequent causes of heart failure.
14
A remarkable observation of the present study was that
HIV in isolation or combination was associated with heart
failure in 12.7% of the patients. This is commensurate with
other studies, which reported that heart diseases such as
pericarditis, myocarditis, cardiomyopathy and endocarditis were
associated with HIV infection.
15,16
The pathogenesis of heart
muscle insufficiency probably involves the direct effects of
the virus on the heart, an inflammatory response of the host
myocardium to the virus, and the presence of auto-antibodies,
as well as decreased immunity, which makes them more prone
to infection.
17
HIV is endemic in Kenya, and its high association
with heart failure suggests that it should always be considered an
important differential diagnosis, and that control of the disease
is important in reducing heart failure.
Tuberculosis in HIV-negative patients was associated with
heart failure in 6.9% of cases. This appears in tandem with
increasing reports of tuberculous pericarditis and myocarditis
with no evidence of HIV, and disseminated TB.
18
Accordingly, as
suggested before, myocardial involvement should be suspected as
a cause of congestive cardiac failure in any patient with features
of TB.
19
Indeed, myocardial TB is well recognised and there are
cases where cardiac TB presents with congestive cardiac failure.
20
Tuberculosis is a common problem in Kenya. Its association
with congestive heart failure is important for two reasons. Firstly,
patients with TB should be monitored for cardiac involvement.
Secondly, in heart failure patients, TB should be considered an
important differential diagnosis.
Anaemia was the second most frequent cause of heart failure,
affecting 17.1% of the children, again in sharp contrast with
reports from developed countries (Table 2). This is, however,
lower than the 28–46% reported from Nigeria.
5,12
The contrast
between European and African countries is concordant with the
suggestion that causes of congestive heart failure in a Kenyan
paediatric population depend on the stage of epidemiological
transaction. The anaemia, similar to literature reports,
21
was
multifactorial, being caused by malaria, intestinal helminths,
poor nutritional status, and haemoglobinopathy. These imply that
a multi-prong approach to the control of anaemia constitutes a
major step in mitigating heart failure.
Rheumatic heart disease is highly prevalent in Kenya, causing
32% of adult heart failure.
22,23
In the current study, it constituted
14.6% of heart failure. It was notably higher than the 1% reported
in Nigeria.
5,12
This implies that control of rheumatic heart
disease, for example, by prudent treatment of throat infections
would substantially reduce congestive heart failure in a Kenyan
paediatric population due to acquired causes. Pertinent to this
suggestion are reports from developed countries indicating that
RHD is no longer a significant cause of CCF.
1,11
Congenital heart disease is the most important cause of infant
heart failure in developed countries.
1,3
In the current study, it
ranks fourth but constitutes 13.3%, slightly higher than the
10.5% reported in a Nigerian study.
5
This is in tandem with
reports that CHD are common in Kenya,
24
and indicates that it
already constitutes a significant cause of heart failure.
Cardiomyopathy is the major cause of heart failure among
children with normal hearts in developed countries.
1,9,11
In the
current study, it constituted 7.6%. This, while lower than the
figures reported for developed countries, is higher than implied
in reports from another African country in which it is not
listed among the causes of heart failure.
5,12
The other causes,
namely adenoids and rickets, are also concordant with literature
reports.
25,26
The treatment modalities provided in KNH are in tandem with
conventional practice.
10
Mortality rate in this series was 7.7%.
This is much lower than the 24% reported in Nigeria
12
and 14%
in Belgium.
9
Outcomes of heart failure are difficult to compare
because of different aetiological factors and accessibility to
healthcare facilities. For example, in developed countries, most
babies with CHD receive early surgical intervention,
27
while
in Kenya, a significant number may miss the opportunity to
have optimal surgical care.
24
Notably, however, the observation
that cardiomyopathy which is known to have a relatively poor
outcome,
28
constitutes only a small proportion of cases, may
partly explain the comparatively low mortality rate. Indeed,
mortality rates have been reported to depend on the cause.
9
This
implies that with control of infection, the outcome of congestive
cardiac failure may improve.
TABLE 2. CAUSES OF PEDIATRIC HEART FAILURE IN DIFFERENT COUNTRIES
Author
Population
Top four causes (%)
Adekambi
et al
. 2007
5
Nigerian
Anaemia (46), infection (29), anaemia + infection (11.5), CHD (10.5)
Massin
et al
. 2008
9
Belgian
CHD (51.6), cardiomyopathy (19.4), RHD (10.5), pericardits (5.6)
Andrews
et al
. 2008
11
United Kingdom Cardiomyopathy (55.8), myocardits (19.6), arrythmia (5.6), anthracycline toxicity (4.0)
Borzouee
et al
. 2008
13
Iranian
CHD (76), RHD (16.1), cardiomyopathy (4.0), other (3.8)
Current study
Kenyan
Infection (22.8), anaemia (17.1), rheumatic heart disease (14.6), congenital heart disease (13.3)
