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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 5, September/October 2016
AFRICA
295
Methods
A total of 4 800 patients identified during routine coronary
angiograms in our clinic between January 2010 and 2013 were
included in the study. The study was planned to be prospective
and was approved by the local ethics committee. After coronary
angiography, the patients were informed about the study and
written consents were given.
Sixty-two patients with isolated CAE, 57 with normal
coronary angiograms (NCA), 73 with severe coronary artery
disease (CAD), and 95 with stenosis of at least one coronary
artery and CAE (CAD
+
CAE) were included in the study. All of
the patients were questioned on their cardiovascular risk factors
and medication used. Routine biochemical and haematological
laboratory tests were done.
Previous history of myocardial infarction, percutaneous
coronary intervention, left ventricular hypertrophy, left
ventricular dysfunction [ejection fraction (EF)
<
50%], moderate
to severe valvular disease, rhythms other than sinus, congenital
heart disease, chronic obstructive lung disease and/or cor
pulmonale, chronic systemic illness, active infection, renal failure,
neoplastic disease, antioxidant drug usage and alcohol abuse
were the exclusion criteria.
Coronary angiography was performed on a Siemens Axiom
Artis angiography device with standard Seldinger’s technique
using isohexol. In order to evaluate each coronary artery, at
least four views from the left and two views from the right side
were taken. Patients were allocated into four groups: patients
with CAD, those with isolated CAE, those with CAD
+
CAE,
and subjects with normal coronary angiograms. Angiographic
images were evaluated by two independent researchers.
Isolated CAE was defined as dilatation of at least one
epicardial coronary artery to 1.5 times the reference vessel
diameter and absence of critical stenosis (
>
50%) in any
of the coronary arteries. NCA were defined as the absence
of angiographic atherosclerosis during routine coronary
angiography; 60% or greater stenosis in at least one epicardial
coronary artery was defined as CAD. CAD
+
CAE was defined
as 60% or greater stenosis in at least one epicardial coronary
artery and the presence of ectasia in any of the coronary arteries.
Serum Mg levels were measured in mg/dl after 12 hours
of fasting. Haemograms, renal and liver function tests, lipid
profiles, serum glucose and electrolytes and thyroid stimulating
hormone (TSH) levels were also evaluated in all patients.
Statistical analysis
Statistical analysis was performed using the SPSS 14 (SPSS
Inc, Chicago, IL, USA) statistics program. Data are given as
percentages and mean
±
standard deviation. ANOVA and
post
hoc
Tukey tests were used in the comparison of parametric
variables between groups. A chi-squared test was performed
in the comparison of non-parametric values and percentages.
Statistical significance level was taken as
p
≤
0.05.
Results
The mean age was 62
±
10 years in the CAE patients, 61
±
11 years in CAD patients, 64
±
8 years in those with CEA
+
CAD, and 59
±
8 years in the NCA patients. There was no
statistically significant difference between the groups in terms of
age, hypertension, smoking, hyperlipidaemia, diabetes mellitus,
family history of CAD, and medications used (Table 1).
Serum glucose, calcium, TSH, urea, total cholesterol,
triglycerides, low-density lipoprotein (LDL) cholesterol, sodium
and potassium levels were similar in both groups (Table 2).
Serum creatinine level was within normal limits in all patients,
however creatinine values were statistically lower in the NCA
group (
p
=
0.024). High-density lipoprotein (HDL) cholesterol
levels were lowest in the CAD patients and highest in the isolated
ectasia group, and this difference was statistically significant (
p
=
0.003).
Serum Mg levels were 1.90
±
0.19 mg/dl in isolated CAE
patients, 1.75
±
0.19 mg/dl in those with CAD, 1.83
±
0.20 mg/
dl in those with CAD
+
CAE, and 1.80
±
0.16 mg/dl in the NCA
group. These results showed that Mg levels were higher in the
ectasia patients with or without CAD.
Discussion
Mg is a divalent cation with powerful vasodilatory effects. In our
study, serumMg levels were found to be statistically higher in the
ectasia patients with or without CAD.
CAE is dilatation of the coronary arteries to at least 1.5 times
normal, and the basic pathogenic mechanism is destruction of
the musculo-elastic layers of the arterial tunica media, and the
accumulation of collagen in place of elastin, leading to thinning
of the arterial wall.
1,5,10
Injury of the media causes decreased
stress tolerance of the vessel wall to intraluminar pressure,
leading to progressive dilatation and ectasia formation.
10,11
In a
pathological examination, atherosclerosis is detected in more
than 50% of patients, however connective tissue disorders and
vasculitides can also be present.
11
CAE can be divided into four different types according to the
classification of Markis and colleagues. Type 1 indicates diffuse
ectasia in two to three different vessels, type 2 shows diffuse
disease in one vessel and local disease in another, type 3 is diffuse
disease in one vessel, and type 4 indicates localised or segmental
ectasia. In our study there were 24 (16%) patients with type 1
Table 1. Comparisons of cardiovascular risk factors and the
medications used
Parameters
Isolated
CAE
(
n
=
62)
CAD
(n
=
73)
CAD
+
CAE
(
n
=
95)
NCA
(
n
=
57)
p
-value
Age (years)
62
±
10 61
±
11 64
±
8 59
±
8 0.062
Gender (M/F)
45/17 39/34 76/19 17/40 0.000
Hypertension (
n
)
43
56
74
35
0.119
Diabetes mellitus (
n
)
13
21
25
12
0.648
Hyperlipidaemia (
n
)
11
13
29
9
0.080
Family history of
CAD (
n
)
18
25
36
16
0.543
Smoking (
n
)
33
32
49
24
0.482
Calcium channel
blockers (
n
)
12
20
23
12
0.744
Beta-blockers (
n
)
24
20
38
12
0.051
Angiotensin converting
enzyme inhibitors (
n
)
21
16
33
11
0.084
Angiotensin receptor
blockers (
n
)
17
26
32
14
0.471
Diuretics (
n
)
15
22
40
16
0.084
Oral antidiabetic (
n
)
11
13
16
10
0.998