CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 6, November/December 2011
306
AFRICA
Down syndrome and congenital heart disease: why
the regional difference as observed in the Libyan
experience?
Z ELMAGRPY, A RAYANI, A SHAH, E HABAS, EH ABURAWI
Abstract
Background:
Children with Down syndrome (DS) have about
a 40 to 50% incidence of congenital heart disease (CHD). The
objectives of this study were to evaluate the distribution and
frequency of CHD patterns in Libyan children with DS.
Methods:
All patients with DS who were referred to the
cardiology clinic between January 1995 and December 2008
were reviewed.
Results:
Of the 1 193 patients reviewed, 537 (45%) had an
associated CHD. Overall there were 349 (65%) patients who
had a single cardiac lesion, and 188 (35%) had multiple
cardiac lesions. The most common isolated cardiac lesion
was atrial septal defect (ASD), found in 125 (23%) patients,
followed by atrioventricular septal defect (AVSD) in 103
(19%), and ventricular septal defect (VSD) in 76 (14%).
Conclusion:
Atrial septal defect was the most common cardi-
ac lesion. The distribution of CHDs in Libyan children with
DS was similar to what has been reported internationally,
but the frequency was not compared with international rates.
Keywords:
congenital heart disease, Down syndrome, geograph-
ical difference, Libya
Submitted 25/10/09, accepted 31/8/10
Cardiovasc J Afr
2011;
22
: 306–309
DOI: 10.5830/CVJA-2010-072
Down syndrome (DS) or trisomy 21 is a chromosomal disorder
frequently associated with a varied combination of morphologi-
cal and structural birth defects. These defects are in the form of
congenital mental disability, hypotonia, characteristic body
features, heart defects, and other systemic congenital malforma-
tions. The frequency and severity of these morphological and
functional defects vary significantly among affected individuals.
The incidence of moderate to severe forms of congenital heart
disease (CHD) in Libya is about 5/1 000 live births.
1
In 1866, John Langdon Haydon Down first characterised
DS as a distinct disease with intellectual impairment.
2
In the
late fifties, Lejeune and Jacobs independently reported that DS
resulted from an extra chromosome 21. Since then the condi-
tion has been known as trisomy 21.
3,4
This particular trisomy is
the most common form of chromosomal abnormality, affecting
about one in 700 live births.
5,6
It is characterised by the whole
chromosomal aneuploidy in about 95% of cases. The remaining
5% is in the form of translocations and mosaics.
7
The risk of
pregnancy with DS increases with the mother’s age, and it can
occur with a frequency as high as one in 30 in those older than
45 years.
8
Approximately 40 to 60% of children with DS have heart
defects and among those with CHD, four to 10% are associated
with DS.
9
The cardiac defects are commonly single, but they can
be multiple as well. It is highly recommended that DS patients be
referred early for cardiac screening. Chest infection, CHD, blood
disorders, leukaemia and lymphoma are not uncommon causes
of death.
10,11
Nowadays, almost all CHD in DS patients are surgi-
cally manageable, with good results. Moreover, the postoperative
morbidity and mortality associated with cardiac surgery has
fallen dramatically in recent years due to advances in intensive
care units, peri-operative care and improved treatment related to
respiratory illnesses.
12,13
The aim of this study was to determine the mode of presenta-
tion, and type and distribution of CHD affecting DS patients in
Libya, and to compare this with previously reported studies.
Methods
In a retrospective descriptive study, medical records of clinically
diagnosed DS patients were reviewed. There were 1 193 children
with DS who had presented to Alfateh University Children’s
Hospital, Tripoli, between January 1995 and December 2008.
After detailed histories and thorough physical examinations were
recorded, two-dimensional echocardiography and Doppler stud-
ies were performed using the ALOKA SSD-800 before 2005,
and the Philips EnVisor C HD, Philips Medical Systems after
2005.
The data were analysed by descriptive statistics, using
Microsoft Excel and Minitab version 16 statistical software pack-
ages. Previously reported literature was reviewed to compare our
results with the international geographical distribution of cardiac
defects in patients with DS.
Results
There were 1 193 patients with DS who attended the cardiac
clinic and of these, 537 (45%) had CHD. The male-to-female
ratio was 1:1.4. The reasons for presentation are given in Table
1, with the commonest being routine screening (44%). Cardiac
The Children’s Hospital, Faculty of Medicine, Alfateh
Medical University, Tripoli, Libya
Z ELMAGRPY, MD
A RAYANI, MD
A SHAH, MD
Medical Department, Faculty of Medicine, Alfateh Medical
University, Tripoli, Libya
E HABAS, MD
Department of Paediatrics, Faculty of Medicine and Health
Science, United Arab Emirates University, Al-Ain, United
Arab Emirates
EH ABURAWI, MD, MSc, FRCPCH, FACC, PhD, e.aburawi@uaeu.
ac.ae
