Cardiovascular Journal of Africa: Vol 22 No 2 (March/April 2011) - page 14

CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 2, March/April 2011
68
AFRICA
in the glucocorticoid arm returned to our hospital to receive
a second intramuscular dose (40 mg) of methyl prednisolone.
Follow-up angiography was done six months after stenting.
Endpoints in our study were myocardial infarction, SCD,
unstable angina, a positive stress echocardiographic test and
observation of stenosis in the follow-up angiography. These
endpoints meant that restenosis had occurred. All steps, that is,
patient selection and randomisation, the initial studies, the first
and second angiography, angioplasty and injections were blinded
and only the head nurse of the CCU knew the patients.
Numerical variables are presented as means
±
SD and
categorised variables are summarised as absolute frequencies
and percentages. Categorical variables were compared using the
chi-square test or Fisher’s exact test if required. For statistical
analysis, the statistical software SPSS version 13.0 for windows
(SPSS Inc., Chicago, IL) was used. All
p
-values were two-tailed,
and statistical significance was defined as
p
0.05.
Results
In this double-blinded, randomised clinical trial, 200 patients
were included and they were divided into two groups of the same
size. The mean diameter and length of stents was 2.7 mm and
19 mm, respectively. The patients were matched regarding age,
gender and four modifiable risk factors: hypertension, hyperlipi-
daemia, smoking and family history. Characteristics of the two
groups regarding age and gender are shown in Table 1.
Twenty-one cases of restenosis were observed in the gluco-
corticoid arm of the study and 24 in the control arm. Restenosis
was estimated with QCA. There was no statistically significant
difference between the two arms in the rate of restenosis. With
regard to the two genders and three vessels involved, we could
not find any statistically significant difference between the two
arms (Tables 2, 3).
Discussion
Our results did not show a preventive role of intramuscular
methyl prednisolone in decreasing the rate of restenosis after
percutaneous stenting of coronary arteries. Also, there was no
significant statistical difference in the subgroups of gender and
vessel involved.
Despite the controversial results of previous studies regarding
the efficacy of glucocorticoids in preventing restenosis, there is
a widely accepted protocol that has been proved to be effective in
most clinical trials performed with glucocorticoids.
18–22
To under-
stand the lack of efficacy of our protocol, one should compare
the time–action profile of our study with this accepted protocol,
which includes administration of oral prednisone for a total of 45
days in different doses: 1 mg/kg for the first 10 days, 0.5 mg/kg
for the next 20 days and 0.25 mg/kg for the last 15 days, starting
on the day of the procedure or the following day.
By comparison, our protocol includes administration of two
intramuscular doses of 40 mg of methyl prednisolone; the first
dose 24 hours before the procedure and the second 14 days after-
wards. Oral prednisolone exerts its effect in one to two days and
intramuscular methyl prednisolone exerts its effect in one to four
weeks. As the potency of the drugs is equal and their bioavail-
ability is almost equal, using our protocol, an 80-kg patient is
exposed to 1/45 the amount given to the patients in the reported
protocol.
26
Conclusion
As previous studies have shown,
25
lowering the dose of cortico-
steroids from this accepted protocol to even half the dose shows
no efficacy in preventing restenosis after stenting, So if we are
to achieve acceptable effectiveness for intramuscular prednisone,
we should increase the doses using shorter intervals, which could
be the target of further studies. However, there would be more
chance of side effects with more frequent doses.
The authors thank the Farzan Institute for Research and Technology for
technical assistance.
References
1. Fischman DL, Leon MB, Baim DS,
et al
. A randomized comparison of
coronary stent placement and balloon angioplasty in the treatment of
coronary artery disease. Stent Restenosis Study investigators.
N Engl J
Med
1994;
331
: 496–501.
2. Serruys PW, de Jaegere P, Kiemeneij F,
et al
. A comparison of balloon-
expandable stent implantation with balloon angioplasty in patients with
coronary artery disease.
N Engl J Med
1994;
331
: 489–495.
3. Briguori C, Nishida T, Adamian M,
et al
. Coronary stenting versus
balloon angioplasty in small coronary artery with complex lesions.
Cathet Cardiovasc Interv
2000;
50
: 390–397.
4. Holmes DR Jr, Vlietstra RE, Smith HC,
et al
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Am J Cardiol
TABLE 1. CHARACTERISTICSAND RATE OF RESTENOSIS
IN THE TWOARMS
Arm
n
Age
(mean
±
SD)
Female
n
(%)
Male
n
(%)
Restenosis
n
(%)
Without
restenosis
n
(%)
Glucocorticoid 100 60.29
±
7.28 42 (42) 58 (58) 21 (21)
79 (79)
Control
100 60.44
±
7.29 46 (46) 54 (54) 24 (24)
79 (79)
TABLE 2. CHARACTERISTICS OF THE TWOARMS
FOR EACH GENDER
Arm
Gender
Total
n
(%)
Without
restenosis
n
(%)
With
restenosis
n
(%)
p
-value
Glucocorticoid Male 54 (100)
40 (74.1) 14 (25.9)
0.831
Control
58 (100)
44 (75.9) 14 (24.1)
Total
112 (100)
84 (75)
28 (25)
Glucocorticoid Female 46 (100)
39 (84.8)
7 (15.2)
0.419
Control
42 (100)
32 (76.2) 10 (23.8)
Total
88 (100)
71 (80.7) 17 (19.3)
TABLE 3. CHARACTERISTICS OF THE TWOARMS
FOR DIFFERENTVESSELS
Arm
Vessel
Total
n
(%)
Without
stenosis
n
(%)
With
stenosis
n
(%)
p
-value
Glucocorticoid
Left anterior
descending
40 (100) 31 (77.5) 9 (22.5) 0.99
Control
50 (100) 38 (76) 12 (24)
Glucocorticoid
Left circumflex 27 (100) 21 (77.8) 6 (23.1) 0.99
Control
27 (100) 21 (77.8) 6 (22.2)
Glucocorticoid
Right coronary
artery
23 (100) 17 (73.9) 6 (17.6) 0.517
Control
23 (100) 17 (73.9) 6 (26.1)
1...,4,5,6,7,8,9,10,11,12,13 15,16,17,18,19,20,21,22,23,24,...60
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