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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 5, September/October 2017
290
AFRICA
there could be more than 500 school children with established
RHD in this single Rwandan district alone. Assuming a constant
prevalence across the country (which may be be unjustified)
extrapolating this RHD prevalence rate to Rwanda’s total
population of school children could prove worrisome with
regard to the accompanying medical, public health and economic
impacts for the country. Such an extrapolation would most likely
indicate that the majority of Rwandan school children with RHD
are most likely undiagnosed and not receiving recommended
medical care, including secondary antibiotic prophylaxis. Our
data further suggest that the preponderance of RHD is most
likely in rural Rwanda. Anticipated studies in additional rural
areas of the country would clarify this.
In extrapolating the present Gasabo data for future public
health planning, the probability of higher RHD prevalence rates
among adolescents and young adults must also be confirmed. If
true, this would require extended coverage by public health RHD
control programmes and medical facilities beyond the primary
school-age population.
The echocardiograms analysed here were obtained by very
experienced, registered cardiac sonographers with an average
of 14 years of experience and were aditionally analysed by
experienced echocardiographers (JM, BB, PA, ER) who had
been given access to an advanced draft of the 2012 WHF criteria
and were aware of the 2012 criteria.
The RHD school-age prevalence of approximately seven per
1 000 children from this single Rwandan district is lower than,
for example, recent reports from Mozambique, Kenya, Uganda,
Ethiopia or South Africa.
7,13-15
The reasons for these differences
are not obvious although variations in prevalence rates were seen
in the previously reported studies. While all of these had high
prevalence rates and the prevalence rate reported here was lower,
one cannot assume that prevalence rates across sub-Saharan
Africa are similar. For example, this finding may be related to
the fact that our study was carried out in and around the capital
city, which may have benefited from better access to healthcare
during the last 10 or 15 years, compared with the rest of the
country. Additionally, Rwanda has been shown to have invested
in primary healthcare and achieved among the best health
indicators in sub-Saharan Africa.
16
There appeared to be a relationship (although not statistically
significant,
p
=
0.704) between the estimated socio-economic
status and prevalence of RHD in this sample of Rwandan
school children. Engle
et al
. have shown similar findings with
Fig. 6.
Example of borderline RHD consistent with WHF 2012 criteria. A. Parasternal long-axis (PLAX) view showing thickened
anterior mitral leaflet exceeding 3 mm and restricted leaflet motion in young adult study subject. B. Colour-flow Doppler
interrogation of the mitral valve in the PLAX view shows a small jet of mitral regurgitation (MR) with jet length < 2 cm. C.
Colour-flow Doppler interrogation of the mitral valve using the A4C view shows jet of mitral regurgitation with jet length < 2
cm. D. Continuous-wave (CW) Doppler interrogation of the MR jet showed maximum velocities exceeding < 3 m/s.
A
C
B
D