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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 5, September/October 2016
AFRICA
279
The 16.7% prevalence of CHD we found is higher than the
9.5% seen in the study by Aimede
et al
.
5
in Abeokuta, but much
lower than the prevalence in the study by Sun
et al
.
16
from eastern
China. These various values may reflect the different influences
of environmental factors on cleft lip/palate. Congenital cardiac
anomaly was more prevalent in cases of cleft palate, and in a
combination of cleft lip and palate, the prevalence was even
higher. This is in keeping with previous works.
5-7,17
Suspected CRS was the commonest ophthalmological referral
for echo in this study and speaks to the endemicity of CRS in our
environment. The high value of CRS in our study may be due to
the lack of routine rubella vaccination in the nation. The highest
prevalence (45.0%) of cardiac anomalies was found among
children referred from ophthalmology. This may have been due
to the high proportion of CRS among the referred children.
Cardiac malformations are particularly common among
children with CRS, especially when the infection occurs early
in pregnancy.
18
In our study, 66.7% of children with suspected
CRS had cardiac anomalies. This high value is consistent with
the findings of 85.7 and 72% by Otaigbe
et al
.
6
in Port Harcourt,
Nigeria and Kyaw-Zin-Thant
et al.
in Myanmar, respectively.
19
This finding also suggests that cardiac anomaly is more
likely in children referred for cataract extraction than for any
other non-cardiac surgical condition. This is because CRS is a
common cause of childhood cataract. The number of suspected
cases of CRS over a five-year period in this study (12) is higher
than the seven cases seen by Otaigbe
et al
.
9
in Port Harcourt,
Nigeria. This may reflect the different levels of activity of the
virus in different localities.
The cardiovascular anomalies in children with cleft lip/
palate were all CHD. The spectrum of CHD consisted mostly
of acyanotic CHD, as documented in the studies from Port
Harcourt and Kano.
6,7
The commonest CHD was atrial septal
defect (ASD) followed by VSD. These CHDs were similarly
reported in earlier studies from Nigeria and outside Nigeria.
6,7,17
The preponderance of ASD may suggest that most of the
children with cleft lip/palate would be asymptomatic and appear
apparently normal on clinical evaluation. This further buttresses
the need for echo evaluation prior to anaesthesia.
PDA and ASD were the commonest CHD in children
referred from ophthalmological surgery, of whom most had
suspected CRS. Most previous studies on children with CRS
also demonstrated PDA and ASD as common CHDs.
8,9
Most
children referred from ENT were for adenoidectomy, which
suggests that the condition is quite prevalent in children.
Only three of the 20 cases with adenoidal hypertrophy had
ventricular hypertrophy. The low prevalence of ventricular
hypertrophy in children with obstructive sleep airway syndrome
has similarly been reported in an earlier study from Ibadan.
20
It
was recommended from the Ibadan study that cardiovascular
evaluation be reserved for children with severe disorder. However
considering the two cases (10%) of ASD among children referred
from ENT in our study, it might be worthwhile continuing
to request echocardiograms for all children with adenoidal
hypertrophy, not only to identify ventricular hypertrophy but
also to detect possible CHD in these children.
Most previous works studied the echo changes in children with
cancers on chemotherapy.
21,22
Ventricular echo indices appeared
normal in cancer patients who were not on chemotherapy.
21
In
our study however, we noted the presence of left ventricular
hypertrophy in the two oncology cases referred for echo. It is not
clear whether the advanced stages of the disease were responsible
for the findings in this study. It is important therefore to study
this group of patients further to evaluate cardiac function,
since the number of these subjects in our study was small. It is
particularly important, as most patients present with advanced
stages of cancer in our environment, and a number of them
undergo anaesthesia for surgery to debulk masses or for open
biopsy.
The children referred fromdentistry were significantly younger
than those from other specialities. This finding may speak to the
need to repair oro-facial clefts early for cosmetic reasons, to
preserve phonation and prevent other complications such as
aspiration pneumonitis. The children referred from ENT were
the oldest, probably since most were for adenotonsillectomy. It
takes a while for adenoidal hypertrophy to reach levels that can
cause obstructive sleep apnoea syndrome and therefore the need
for surgical intervention.
The left ventricular function of the study population was
adequate, irrespective of whether they had cardiac anomalies or
not. This was demonstrated by the normal median values of the
EF and FS in the study population and the lack of a significant
difference between the median FS and EF of the children with
cardiac anomalies and those without anomalies.
There are limitations to the interpretation of our results.
It was a retrospective review with the attendant problems of
missing records, poor documentation or insufficient clinical
information. However the problems of missing records or
poor documentation were obviated by the single source of
echocardiography and uniform documentation of findings.
Secondly, the observed prevalence of cardiac anomalies does
not represent the prevalence in the community. Most of the
children were delivered in the hospital or sought further care in
our centre. Echo detection of cardiac anomalies in the children
referred for pre-anaesthetic evaluation remains the strength of
this study.
Conclusion
Of the children referred for pre-anaesthetic echo evaluation,
21.5% had cardiac anomalies. The 16.7% prevalence of CHD
among children with oro-facial clefts was high. Children with
cleft palate had a higher prevalence of CHD compared with those
with cleft lip only. Suspected CRS was the commonest reason for
ophthalmological referral and accounted for 66.7% of cases with
CHD. There was a low prevalence of ventricular hypertrophy
in children with AH, some of whom had CHD, prompting the
need for continued pre-anaesthetic echo evaluations. The cardiac
anomalies were mostly acyanotic CHD. The children with
congenital anomalies from other surgical units were more likely
to have a positive echocardiographic screening. It is therefore
recommended that pre-anaesthetic echocardiographic evaluation
should be continued for children, especially those with suspected
CRS and oro-facial clefts, and those with congenital anomalies.
References
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