CARDIOVASCULAR JOURNAL OF AFRICA • Volume 25, No 3, May/June 2014
AFRICA
131
The remaining lesion was operated on during CABG. The
arteriotomy was closed using a patch in 108 patients (98.2%),
except for two patients (1.8%) who underwent primary closure.
Bleeding control was achieved. The incision was left open.
Following the median sternotomy, on-pump CABG was
performed with systemic hypothermia maintained at 32°C using
two-stage venous and aortic cannulae. Mean arterial pressure
was maintained at 60 mmHg during cardiopulmonary bypass
(CPB). Operative findings are presented in Table 1.
Statistical analysis
Statistical analysis was performed using SPSS for Windows
v 13.0 software (SPSS Inc, Chicago, IL, USA). Descriptive
statistics were used to summarise both quantitative data including
the mean, standard deviation, and maximum and minimum
values, and categorical variables including frequency distribution
and percentage.
Kolmogorov–Smirnov and Shapiro–Wilks tests were used
to analyse normally distributed variables. One-way analysis of
variance (ANOVA) was performed to determine the significance
of differences between the groups. The chi-square test was
also used to identify possible correlations among the variables,
while the Spearman test was carried out to calculate power and
direction of the correlation. A 95% confidence interval (CI)
was calculated. A
p
-value of
<
0.05 was considered statistically
significant.
Results
A total of 86 patients (78.2%) were male and 24 (21.8%) were
female. The mean age was 65.11
±
7.81 years (range 44–85
years). Demographic characteristics and clinical data of the
patients are shown in Table 2.
Of these patients, 27 were symptomatic, while 83 were
asymptomatic. All patients who were operated on had ipsilateral
carotid artery disease. Only four patients had
≥
80% contralateral
carotid artery stenosis. One patient (0.9%) with a cerebrovascular
accident died due to subsequent ventricular arrhythmia in
the early phase. Four patients (3%) had postoperative major
stroke, whereas three (2%) had transient hemiparesis. No peri-
operative MI was observed. Early postoperative complications
are summarised in Table 3.
Spearman’s correlation showed a positive correlation between
the duration of cross-clamping and shunt usage (40%). The mean
duration of cross-clamping was 15.9 and 21.1 min in patients
without and with shunts, respectively. It reached statistical
significance (
p
<
0.049). Although shunt implantation prolonged
the duration of cross-clamping, there was no statistically
significant difference in neurological complication rate (
p
=
0.301).
In addition, four patients had haematoma and neurological
complications due to local bleeding. One patient required re-do
CABG surgery. Another patient underwent revision surgery due
to sternal dehiscence. Three patients underwent revision surgery
due to bleeding following CABG.
Discussion
Today individuals with concomitant carotid and coronary
artery disease are still challenging patients for surgeons. With
increasing age of patients and stenosis rate, it is obvious that
this will become more significant in future years.
7
The incidence
of carotid stenosis has been estimated as 12% in patients with
coronary artery disease.
4,18
Nearly half of the patients with carotid
artery disease also have concomitant coronary artery disease.
19
Peri-operative prevention of myocardial and cerebral accidents
is an ongoing debate. Several studies have demonstrated a
mortality rate for simultaneous CEA and CABG of 0–8.9%
and a stroke rate of 0–9%.
4-9,19
Lower mean arterial pressures of
cardiopulmonary bypass, systemic vasodilatory response and
plaque embolism during aortic cross-clamping increase the risk
of peri-operative stroke in CABG patients.
20
In a randomised study, Roach
et al
.
21
reported a neurological
complication rate of 6.1% in patients who underwent elective
CABG surgery, with serious complications in 3%. The authors
Table 1. Operative findings
Findings
Numerical values
Number of distal anastomoses
296
Grafted patient rate (%)
2.69
CPB time (min)
51.72
±
17.15 (23–95)
ACC time (min)
24.39
±
8.41 (11–46)
Duration of carotid clamping (min)
18.56
±
7.23 (9–42)
Carotid closure technique [
n
, (%)]
Primary
2 (1.8)
Vein
50 (45.5)
Hemashield
58 (52.7)
CPB, cardiopulmonary bypass time; ACC, aortic cross-clamping time.
Table 2. Demographic and clinical characteristics
Characteristics
Number of
patients (n)
Percentage
(%)
Gender
Female
24
78.2
Male
86
21.8
Previous myocardial infarction
28
25.5
Neurological history
Asymptomatic
82
74.5
Symptomatic
27
24.5
Hypertension
77
70
Smoking
38
34.5
Diabetes mellitus
39
35.5
Hyperlipidaemia
34
30.9
Peripheral artery disease
19
17.3
Mean age 65.11
±
7.81 years, range 44–85
Table 3. Postoperative complications
Complications
Number
Percentage
Early mortality
1
0.9
Persistent hemiplegia
3
2
Transient hemiparesis
4
3
Transient ischaemic attack
1
0.9
Peri-operative myocardial infarction
0
0
Ventricular arrhythmia
2
1
Atrial fibrillation
3
2
