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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 2, March/April 2016
86
AFRICA
the prevalence was 41.8% in women.
15
The Latin American
Consortium of Studies in Obesity (LASO), in its study on the
major cardiovascular risk factors in Latin America, found
that the prevalence of diabetes mellitus, hypertension and low
levels of high-density lipoprotein (HDL) cholesterol in Latin
American countries were 5, 20.2 and 53.3%, respectively.
16
In
this study, women had a higher prevalence of obesity and lower
HDL cholesterol levels than men and, compared to the region’s
average, the prevalence of each risk factor tended to be lower in
Peru and higher in Chile.
In LMICs, a search for cardiac disease in pregnant women is
not performed routinely although hypertensive disease, rheumatic
heart disease and cardiomyopathies are recognised as the largest
drivers of maternal mortality. Among the cardiomyopathies,
peripartum, Chagas disease and endomyocardial fibrosis
present specific challenges due to their poor prognosis and
high prevalence in some geographical areas. Cardiovascular
manifestations of HIV/AIDS is a major concern due to the
higher prevalence of infection in African women and lower mean
age of those affected, compared to men.
17
Undetected or untreated congenital heart defects continue
to be diagnosed during pregnancy, which is witness to the fact
that advances in paediatric cardiology and cardiac surgery over
the last decades have benefited disproportionately women from
developed countries, compared to those living in the developing
world. In fact, pulmonary hypertension and severe heart failure
complicating pregnancy are a common presentation when
surviving girls reach their reproductive years. In specific endemic
regions, sickle cell disease and other haemoglobinopathies
may constitute important challenges by increasing the risk of
thromboembolic complications due to the hypercoagulability
caused by enhanced platelet function, activation of the
coagulation cascade and impaired fibrinolysis in pregnant
women.
18
Current data on morbidity and mortality rates
Data on mortality rates of pregnant women with cardiac
disease vary widely among LMICs, as data from hospital-
based studies with variable designs and different geographical
contexts suggest. Hypertension (pregnancy in hypertensive
women and hypertension aggravated by pregnancy) is probably
the single most important cardiovascular risk factor linked to
adverse maternal and neonatal outcomes in LMICs.
19
Regarding
non-obstetric (indirect) causes, a retrospective analysis on 144
pregnancies in women with cardiac disease who delivered
in a single centre in Turkey showed that rheumatic (87.5%)
and congenital heart disease (12.5%) were the only causes of
disease, with 44.4% of patients presenting in New York Heart
Association classes II–IV. Although there was no maternal
mortality, morbidity was observed in 16 (11.1%) cases, strongly
related to the severity of cardiac disease.
20
In India, cardiac
causes were responsible for 27 of the 277 (9.75%) maternal
deaths that underwent a pathological autopsy in a tertiary
healthcare centre.
21
Data from Iran revealed a maternal mortality
rate of 4.0% (
n
=
8), with pregnant women with congenital heart
disease experiencing higher mortality rates.
22
Although data from Africa are scarce, maternal morbidity
and mortality related to heart disease may reach unacceptably
high rates. A systematic review of pre-existing cardiac disease in
pregnant women in South Africa found seven studies where the
prevalence of heart disease ranged from 123 to 943 per 100 000
deliveries, with a median prevalence of 616 per 100 000.
23
In this
African country, maternal mortality has quadrupled over the
last decade, being responsible for 41% of the indirect causes of
death; 77% of cardiac deaths occurred in women who attended
antenatal clinics, showing major gaps in care and loss of
opportunities to diagnose and adequately manage when women
contact health services.
24
Postmortem autopsy findings from
cases of maternal death at a tertiary hospital in Nigeria over
a five-year period revealed that 84 cases (28.6%) of maternal
deaths were due to non-obstetric causes, with 20.8% of them
being linked to pre-existing hypertension.
25
Sliwa
et al
. studied 225 women presenting to a single tertiary
care centre in South Africa with cardiovascular disease in
pregnancy or within six months’ postpartum, showing that
54% of pregnant women presented to specialised care for the
first time with a gestational age over 24 weeks.
26
This study also
showed that women present at late stages of disease, since only
73 (32.4%) were in World Health Organisation (WHO) class I.
The most common problems in the 152 women in WHO class
II–IV were congenital heart disease (32%), cardiomyopathy
(27%) and rheumatic heart disease (26%). Maternal mortality
rate within the six-month postpartum follow-up period was
9/152 (5.92%) with all deaths occurring in symptomatic women
(WHO class III or IV risk group). The main diagnoses leading to
death were familial and peripartum cardiomyopathy (
n
=
7) and
prosthetic valve complications (
n
=
2). Interestingly, eight out
of nine deaths occurred outside the 42-day maternal mortality
report period, meaning that they were not considered in the
statistics as maternal deaths.
In LMICs, rheumatic heart disease contributes to 30%
of the cardiovascular disease seen in pregnancy and remains
an important determinant of morbidity and mortality.
27-29
Rheumatic valvular lesions were the commonest abnormalities
found in South Africa, where the most frequent complications
were pulmonary oedema, thromboembolism and major bleeding
related to warfarin use.
26
In the global prospective registry of
rheumatic heart disease (REMEDY), which enrolled 3 343
patients presenting at 25 hospitals in 12 African countries, India
and Yemen, young females were highly represented (median age
28 years, females 66.2%) and had a higher prevalence of major
cardiovascular complications.
30
The participating countries were grouped into three
income categories according to 2011 World Bank definitions:
low-income countries (Ethiopia, Kenya, Malawi, Rwanda,
Uganda and Zambia), lower-middle-income countries (Egypt,
India, Mozambique, Nigeria, Sudan and Yemen), and upper-
middle-income countries (Namibia and South Africa). There
was no difference in the predominance of females in the three
groups: 728/1 110 (65.8%) 867/1 370 (63%) and 616/863 (71.3%),
respectively. However, a statistically significant difference was
found in the proportion of women in child-bearing years
between the three groups of countries (86.5% in low-income
countries, 90.3% in LMIC and 66.9% in upper-middle-income
countries;
p
<
0.01). Among 1 825 women of childbearing age
(12–51 years), only 65 (3.6%) were on contraception, reflecting
the poor provision of family planning and pre-pregnancy advice
for women with heart disease that occurs in many regions of the
world.
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