40 / 64
CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 6, November/December 2020
320
AFRICA
explorations had excluded the diagnosis of ACS, and patients
transferred to another department outside the Abidjan Heart
Institute during their hospitalisation.
Consent was obtained from each patient participating in
this study. Based on our selection criteria, 1 168 patients were
included in our study.
Data were collected using a standardised survey form. The
parameters investigated were: (1) socio-demographic data (age,
gender) as well as clinical data (cardiovascular risk factors and
history, clinical presentation); (2) ECG (diagnosis of ACS)
and cardiac ultrasound data [left ventricular ejection fraction
(LVEF)
<
40% or
≥
40%]; (3) biological data: troponin Ic and
cardiac enzymes, (4) coronary angiography findings: number
of epicardial vessels affected (one-, two- and three-vessel
disease), (5) management: dual antiplatelet therapy (DAPT),
percutaneous coronary intervention (PCI), and (6) in-hospital
evolution: atrial fibrillation, sustained ventricular tachycardia/
ventricular fibrillation, cardiogenic shock, death.
Hypertension was defined as systolic blood pressure
≥
140
mmHg and/or diastolic blood pressure
≥
90 mmHg, measured
three times during hospitalisation or treatment of previously
diagnosed hypertension. DM was defined according to the
American Diabetes Association
13
as one of the following criteria:
glycated haemoglobin
≥
6.5%, fasting plasma glucose
≥
1.26 g/l
(6.99 mmol/l) on two occasions, two-hour plasma glucose
≥
2 g/l
(11.1 mmol/l) after 75-g oral glucose tolerance test (OGTT),
random plasma glucose
≥
2 g/l (11.1 mmol/l), or patients on
glucose-lowering therapy on admission. Active smoking was
defined as current or interrupted smoking for less than three
years.
Dyslipidaemia was defined as total cholesterol concentration
> 2.40 g/l (6.22 mmol/l) and/or high-density lipoprotein (HDL)
cholesterol
<
0.40 g/l (1.04 mmol/l) in males and
<
0.50 g/l
(1.3 mmol/l) in females and/or low-density lipoprotein (LDL)
cholesterol > 1.60 g/l (4.14 mmol/l), or triglyceride levels > 1.5 g/l
(1.70 mmol/l). Familial history of coronary artery disease (CAD)
was defined as the occurrence of a myocardial infarction or
sudden death: before the age of 55 years in the father or in a first-
degree male relative; and before the age of 65 years in the mother
or in a first-degree female relative. Symptom–admission delay
was the time between the onset of symptoms and admission to
the Abidjan Heart Institute.
ST-segment elevation myocardial infarction (STEMI) was
defined as the presence of symptoms or signs of myocardial
ischaemia, persistent ST-segment elevation or newly diagnosed
bundle branch block, and an increase in cardiac biomarkers
beyond the 99th percentile.
6
Non-ST-elevation ACS (NSTE-
ACS) was defined as the presence of symptoms or signs
of myocardial ischaemia, absence of persistent ST-segment
elevation, and elevation (non-Q-wave myocardial infarction) or
no elevation (unstable angina) of cardiac biomarkers beyond
the 99th percentile.
14
Left ventricular systolic dysfunction was
defined for a LVEF
<
40%.
15
Statistical analysis
Continuous variables are presented as mean ± standard deviation
or median (interquartile range). Categorical data are presented
as numbers and proportions. Statistical comparisons between
groups used the Student’s
t
-test or Mann–Whitney test for
continuous variables, and the chi-squared test or Fisher’s exact
test for categorical variables. A receiver operating characteristics
(ROC) curve was performed to determine the admission
glycaemic threshold level predictive of death in our population.
Univariate and multivariate backward stepwise logistic
regressions were used to assess predictors of in-hospital death,
with an inclusion threshold of
p
<
0.20 in the multivariate
analysis. The candidate variables considered were selected
according to available data in the literature. The Wald (or Fisher)
test was used to assess the significance of hazard ratio (HR) and
their 95% confidence interval (95% CI). We defined statistical
significance using a two-sided
p
-value
<
0.05. We used RStudio
statistical software version 1.1.383 (Boston, MA, USA).
Results
Table 1 summarises the patients’ general characteristics and
outcomes according to blood glucose status at admission.
Among the 1 168 patients included in our study, 474 had AH,
with a prevalence of 40.6%. The average age of our study
population was 56.0 ± 11.6 years (range 21–91). Patients in the
AH group were significantly older than those in the NAH group
(57.9 ± 11.0 vs 54.7 ± 11.8 years,
p
<
0.001). Patients over 60
years old frequently had acute hyperglycaemia (40.7 vs 31.7%,
p
=
0.001). The male gender was predominant (80.7%) with a
ratio of male to female of 4.2. Patients in the NAH group were
more likely to be female, with no significant difference (Table
1). According to cardiovascular risk factors and history, AH
patients had significant increases in hypertension (
p
<
0.001) and
DM (
p
<
0.001). Smoking was frequently reported in the NAH
group (
p
=
0.002).
The median symptom–admission delay was 19 hours (5–48).
There was no difference concerning blood glucose levels at
admission (
p
=
0.37). Heart failure often occurred in AH
patients (35.4 vs 20.7%,
p
<
0.001). AH patients presented with
increased blood pressure and heart rate. In AH patients, peaks
in troponin Ic (
p
=
0.004), creatine phosphokinase (CPK) (
p
<
0.001) and creatine kinase-MB (CK-MB) levels (
p
<
0.001) were
higher. Coronary angiography was performed in 564 patients
(48.3%). Although there was no significant difference (
p
=
0.51),
three-vessel disease was more common in AH patients (Table
1). Two hundred and twenty patients underwent PCI (18.8%).
Dual antiplatelet therapy (aspirin + clopidogrel) was given to
782 patients (67.0%). No differences were reported between the
groups.
Over the study period, 800 STEMI patients out of 1 138
(68.5%) were admitted to ICU. Thrombolysis was performed in
93 patients, in most of the cases with Alteplase (77/93, 82.8%).
PCI procedures started on 27 April 2010. One hundred and fifty-
one STEMI patients underwent PCI.
Cardiogenic shock occurred significantly in patients with
acute hyperglycaemia (
p
<
0.002). Atrial fibrillation and severe
ventricular arrhythmias (sustained ventricular tachycardia or
ventricular fibrillation) were more frequent in the AH group,
without significant difference. Overall in-hospital mortality rate
was 9.1% (106/1168). It was higher in AH patients (15.2%,
p
<
0.001) (Table 1).
In multivariate analysis, heart failure (HR
=
2.22; 1.38–3.56;
p
=
0.001), LVEF
<
40% (HR
=
6.41; 3.72–11.03;
p
<
0.001), acute
hyperglycaemia (HR
=
2.33; 1.44–3.77;
p
<
0.001), sustained