CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 4, May 2013
110
AFRICA
Non-ST elevation myocardial infarction (NSTEMI) in
three hospital settings in South Africa: does geography
influence management and outcome?
A retrospective cohort study
JANE MOSES, ANTON F DOUBELL, PHILIP G HERBST, KARL JC KLUSMANN, HELLMUTH SVH WEICH
Abstract
Background:
Guidelines advise early angiography in non-ST
elevation myocardial infarction (NSTEMI) to ensure an opti-
mal outcome. Resource limitations in secondary hospitals in
the Western Cape dictate a local guideline to treat NSTEMIs
medically with out-patient assessment for angiography,
unless mandatory indications for early angiography occur.
Methods:
A retrospective cohort study assessed NSTEMIs
at Tygerberg Hospital (TBH), Karl Bremer Hospital (KBH)
and Worcester Hospital (WH) over one year. Two cohorts
were analysed, secondary hospitals (KBH and WH; SH) and
secondary service within a tertiary hospital (TBH). Where
differences were found, sub-analysis comparedWH and KBH.
Results:
TBH and SH were similar at baseline and in clini-
cal presentation. Cases at TBH were more likely to receive
in-patient angiography (94 vs 51%,
p
<
0.0001), and had a
lower in-patient mortality rate (6 vs 23%,
p
=
0.0326). There
was no difference between KBH and WH in sub-analysis.
Conclusion:
This study confirmed that the management and
mortality of NSTEMIs in the public health sector in the
Western Cape, South Africa is not influenced by geography,
but rather by the level of service available in the hospital of
first presentation.
Keywords:
acute coronary syndrome, NSTEMI, myocardial
infarction
Submitted 19/9/12, accepted 18/3/13
Cardiovasc
J Afr
2013;
24
: 110–116
DOI: 10.5830/CVJA-2013-017
The European Society of Cardiology (ESC) guidelines state that
patients presenting with an acute coronary syndrome (ACS)
with raised cardiac markers and without ST-segment elevation
(non-ST elevation myocardial infarction – NSTEMI), should
receive early coronary angiography and revascularisation,
1
as
trials have shown clear mortality benefit for such an early
invasive approach.
2-6
The South African Heart Association is an
affiliated member of the European Society of Cardiology (ESC)
and therefore subscribes to its guidelines, but strict adherence is
not always possible due to limited facilities and personnel.
The South African public health service is divided into three
levels of care; primary care (managed by family physicians),
secondary care (with certain specialists such as specialist
physicians but without sub-specialist care), and tertiary care
(provided by academic referral hospitals and with access to
sub-specialist services such as cardiologists). These tertiary
centres are usually located in large cities, resulting in inequality
in the distribution of sub-specialist care. This may be detrimental
to many patients presenting to secondary hospitals but the extent
of this is unknown. Furthermore, the studies on which these
guidelines are based were performed in the first world and
may not be applicable to our patients or practice, even to those
presenting primarily to sub-specialist centres.
7-10
Current best-practice guidelines as practiced in secondary
hospitals in the Western Cape suggest patients with NSTEMIs
be admitted for medical management, including bed rest, anti-
platelet treatment with aspirin,
β
-blockade, anti-coagulation
with heparin (unfractionated or low molecular weight; LMWH)
and nitrates (sub-lingual or intravenous). All patients are given a
statin for secondary prevention and should their blood pressure
allow, all are prescribed an angiotensin converting enzyme
inhibitor (ACE inhibitor) or an angiotensin receptor blocker
(ARB). This treatment is continued for 48 hours provided the
patient remains pain free. Cardiac enzymes are taken at least
once, six to 12 hours after the index pain.
Should the patient be haemodynamically unstable or
experience on-going ischaemia (on-going/recurrent chest pain
or dynamic ischaemic ECG changes), referral to a tertiary centre
for angiography is indicated. Patients with a TIMI score
11
of 5 or
more are also referred.
Should the patient remain asymptomatic on medical
management, heparin anticoagulation is discontinued after 48
hours and the patient is mobilised. If the patient develops
recurrence of ischaemic chest pain on mobilisation, referral to
a tertiary centre for angiography follows. Should the patient
mobilise without complication, a sub-maximal exercise stress
test (EST) is performed pre-discharge where possible to exclude
poor prognostic features, which also dictate referral. Patients
who do not demonstrate any of these features are referred to the
tertiary centre as out-patients.
The current best-practice guidelines therefore aim to identify
a small group of very high-risk patients who are referred for
early angiography, whereas medical management is considered
sufficient for those who stabilise on heparin anticoagulation
Division of Cardiology, Department of Medicine, Stellenbosch
University and Tygerberg Hospital, South Africa
JANE MOSES, MB ChB, FCP (SA), MMed (Int Med), drjanemoses@
gmail.com
ANTON F DOUBELL, MB ChB, MMed (Int Med), FCP (SA), BSc
Hons, PhD (Med Biochem)
PHILIP G HERBST, MB ChB, MRCP (UK), FCP (SA), Cert Cardiol (SA)
HELLMUTH SVH WEICH, MB ChB, MRCP (UK), MMed (Int Med),
Cert Cardiol (SA)
Department of Medicine, Stellenbosch University and
Worcester Hospital, South Africa
KARL JC KLUSMANN, MB ChB, MSc (Sports Med), MMed (Int Med)
