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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 2, March/April 2018
AFRICA
e11
43% of these had coronary atherosclerosis and 21% had
coronary thrombus without evidence of atherosclerotic disease.
In addition, 16% had spontaneous coronary artery dissection,
while 29% had normal epicardial coronaries.
10,11
Anterior wall
myocardial infarction was the most common occurrence to be
reported.
In earlier reports, myocardial infarction was associated with
a maternal mortality rate of 21% or higher. However in recent
reports, the mortality rate was estimated to be between 5 and
11%, and most foetal deaths were associated with maternal
deaths.
1,2,10-12
Most importantly, most maternal deaths occurred at
the time of an acute myocardial infarct or within two weeks of
the acute event, usually related to labour and delivery.
A literature survey by Ladner
et al
.
13
reported a total of
151 women with AMI, yielding an incidence rate of one in
35 700 deliveries. This report was supportive of the study by
Roth
et al
.,
10,11
who reported that AMI was more common in
women older than 35 years and often in multiparous women.
Important independent risk factors for AMI included chronic
hypertension, diabetes, advanced maternal age, eclampsia and
severe pre-eclampsia. The same authors reported a maternal
mortality rate of 7.3% and also indicated that maternal death
only occurred in those women with AMI before or at the time
of delivery.
10,11
In addition, the authors reported that 38, 21
and 41% of the incidences occurred during the antenatal and
intrapartum periods and six weeks postpartum, respectively; and
the incidence of AMI increased over the 10-year study period.
1,2,14
Hankins
et al
.
12
emphasised that delivery within two weeks of
infarction was associated with increased mortality rates and in
addition, an increased risk of re-infarction occured during labour.
The reporters indicated that increased cardiovascular stresses
late in pregnancy, especially when intensified by parturition,
compromise women with IHD. As a result, efforts should
be made to limit myocardial oxygen demand/consumption
throughout pregnancy and particularly during parturition.
Percutanous coronary intervention (PCI) during
pregnancy
James
et al
.
1,2
reported on revascularisation by PCI in a total
of 135 patients, with stent deployment in 127 of the patients.
1,2
However, information on outcomes was limited.
In another study, more data were reported on 92 of 103
patients who had coronary angiography, where 49 and 43
of these patients had the procedure during the antepartum
and postpartum periods, respectively.
15-17
PCI was subsequently
performed in 38 (41%) of the patients (23 antepartum, six
peripartum and nine postpartum) with stent placement in
only 55% of the patients and bare-metal stents deployed in all
patients. Drug-eluting stents should be avoided during pregnancy
if possible due to limited information on their safety.
15-17
Coronary arterial bypass grafting during pregnancy
Although information regarding the safety of coronary arterial
bypass grafting (CABG) during pregnancy is limited, James
et
al
.
1,2
reported surgical revascularisation in 61 women with AMI
during pregnancy. Despite this impressive number of patients
who had undergone surgical revascularisation, information on
the outcome of these procedures was not provided.
Dufour
et al
.
18
reported data on pregnancy in patients who
had had a previous myocardial infarction with or without
prior CABG. In the majority of patients who died, their death
occurred at the time of myocardial infarction, and maternal
mortality rate was the greatest if myocardial infarction occurred
late in pregnancy.
Prevalence of acute coronary syndromes (ACS)
during pregnancy
The prevalence of myocardial infarction during pregnancy was
previously estimated at one per 10 000 pregnancies, however
current estimates indicate that the prevalence has increased
three to four times, more often in middle- and high-income
women.
19-25
Myocardial ischaemia during pregnancy can mimic
typical symptoms related to pregnancy itself, which may be
misinterpreted, resulting in under-reporting of the incidence.
When myocardial infarction does occur, it may be associated
with both maternal and neonatal mortality, and the risk increases
during the peripartum period, particularly during labour and
within a few weeks of delivery.
Although most cases of myocardial infarction in
non-pregnant patients are due to coronary atherosclerosis,
alternative aetiologies should always be looked for in pregnancy.
Pregnancy is a hypercoagulable state, which increases the risk of
AMI, as does older age at the time of conception.
23-25
Changes in
the cardiac, haemodynamic, haemostatic and hormonal milieu
during pregnancy and the puerperium period create a spectrum
of stresses that may provoke ACS. Spontaneous coronary
dissection is one of the commoner and more important causes
of ACS in these patients.
15,26-41
Conclusion
Although IHD was previously presumed to be rare in pregnancy,
current reports estimate a three- to four-fold increase, more often in
middle- and high-income women. Pregnancy, due to its associated
hypercoagulable state, is a major risk factor for cardiovascular
disease in the current era. Changes in lifestyle, including cigarette
smoking, diabetes and stress, and delayed childbearing until older
age further increase the risk of IHD in pregnancy.
The management of IHD in pregnancy, particularly AMI,
remains controversial due to limited data. Bare-metal stents are
reported to be the preferred choice of intervention compared
with drug-eluting stents due to limited information and risk
of prolonged anticoagulation. In addition, since information
regarding the safety of CABG during pregnancy is rather
limited, CABG should not be recommended as the first option.
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James A, Jamison M, Swamy G, Myers E. Acute myocardial infarction
during pregnancy and postpartum.
Am J Obstet Gynecol
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James AH, Jamison MG, Biswas MS, Brancazio LR, Swamy GK,
Myers ER. Acute myocardial infarction in pregnancy – A United States
population-based study.
Circulation
2006;
113
: 1564–1571.
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Mayosi BM. National Rheumatic Fever Week: The status of rheumatic
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