CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 6, July 2013
AFRICA
215
Neurological complications have a major effect on post-operative
morbidity and mortality and the outcome may be catastrophic for
both the patient and surgeon. The rate of stroke after cardiac
surgery is reported to be between 1 and 5% in published studies
and this may increase to 9% in patients over 75 years of age.
1,4
Indeed, mortality may reach 28% in the latter cases.
5-7
Cerebral damage and neurological complications due to this
damage have many causes, including embolisations originating
in the heart and aorta (air, particles from ruptured plaques, fatty
particles), cerebral hypo-perfusion, bleeding, carotid artery
disease, and metabolic causes such as toxic mediators and
cytokines released during prolonged ECC.
8,9
The dimensions
of the neurological damage are dependent on the extent of
embolisation and the affected region.
There are publications in which single aortic clamping is
recommended for proximal and distal anastomosis in CABG
surgery, in order to decrease the rate of such complications.
4,8,10,11
Aranki
et al
.
12
reported a decrease in both hospital mortality and
cerebral damage with the use of the single-clamp technique.
Marshall
et al
.
13
have shown that most of the embolisations
occurred during manipulation of the aorta, especially when the
clamp was removed from the aorta.
In the Framingham study, the rate of stroke was 3.5 times
higher in patients over 65 years, with a calcification in their
aorta. The rate of sudden death due to coronary artery disease
was found to be twice as high in patients younger than 65 years,
with radiological aortic calcifications, in comparison with
patients without aortic calcifications in the same study.
14,15
Akpınar
et al
.
5
reported performing coronary artery bypass
grafting with only arterial grafts, by inducing ventricular
fibrillation with deep hypothermia in 23 patients who had
advanced calcifications in the aorta. The mean age of these
patients was 65 years, and major neurological complications
were not observed in any of them. We utilised this method in
only one of our patients in this series, a patient on whom we had
operated in the past five years. However, like other patients in
whom plaques were detected in the aorta, this patient was not
included in this study.
In a study by Orhan
et al
.,
1
partial clamping was compared
with single clamping during coronary bypass operations, and
no statistical differences were observed between these groups
in terms of stroke and neurological problems. In a study by
Us
et al
.,
8
neurological complications were not observed in
patients in whom the single-clamp technique was used, whereas
neurological complications were statistically significantly higher
in those in whom partial clamping was used.
Güden
et al
.
16
recommend the single-clamp technique in CABG surgery, as
this approach minimises possible embolisations from the aorta
TABLE 1. DEMOGRAPHIC, CLINICALAND PROCEDURAL
DATA FOR STUDY PATIENTS
Group 1 (
n
=
1500) Group 2 (
n
=
500)
p
-value
Parameters
Patient
number
%
Patient
number
%
Age (mean
±
SD)
63.25
±
5.72
64.83
±
8.12
0.079
Female gender
654
43.6
214
42.8 0.46
Cardiac data
Acute MI
93
6.2
29
5.8 0.065
Heart failure (pre-operative)
486
32.4
144
28.8 0.058
Risk factors
Smoking
564
37.6
191
38.2 0.95
Hypertension
768
51.2
254
50.8 0.73
Morbid obesity
276
18.4
96
19.2 0.66
Dyslipidaemia
1023
68.2
339
67.8 0.97
Family history
357
23.8
109
21.8 0.39
Peripheral vascular disease
192
12.8
56
11.2 0.38
MI (pre-operative)
648
43.2
214
42.8 0.73
DM
675
45.0
223
44.6 0.73
COLD
333
22.2
109
21.8 0.90
CRF
84
5.6
26
5.2 0.13
NYHA class (mean
±
SD)
3.24
±
7.1
3.18
±
1.2
0.65
EF (mean
±
SD) (pre-operative) 45.46
±
5.23
46.41
±
2.31
0.067
LMCA lesion
375
31.51
685
29.65 0.567
Mean
±
SD, mean
±
standard deviation; MI, myocardial infarction; DM, diabetes melli-
tus; COLD, chronic obstructive lung disease; CRF, chronic renal failure; NYHA, New
York Heart Association; EF, ejection fraction; LMCA, left main coronary artery.
TABLE 2. COMPLICATIONSAND MORTALITYAFTER
CORONARYARTERY BYPASS GRAFTING
Group 1
(
n
=
1500)
Group 2
(
n
=
500)
p
-value
Number of distal anastomoses (mean
±
SD) 2.98
±
1.9 (1–5) 3.12
±
2.1 (1–4) 0.96
Time of cross clamp (min) (mean
±
SD)
41
±
4.3
69.6
±
1.3 0.001
Time of perfusion (min) (mean
±
SD)
67.3
±
3.6
76.7
±
2.2 0.001
Positive inotropic support (%)
31.2
29.4
0.43
IABP (%)
1.26
0.8
0.001
Time in operating room (min) (mean
±
SD) 187.95
±
2.32 185.25
±
7.35 0.072
Using grafts
LITA,
n
(%) (for LAD coronary artery)
2275 (98.48)
483 (96.62%)
0.001
Blood transfusion (units)
3.1
±
1.4
2.8
±
2.7
0.001
Days in ICU (mean
±
SD)
1.2
±
2.1
1.8
±
2.3
0.001
Total days in hospital (mean
±
SD)
5.1
±
2.8
4.9
±
3.6
0.46
Post-operative bleeding (ml)
550
±
2.6
490
±
2.6
0.001
Intubation time (hour) (mean
±
SD)
7.86
±
9.2
12.67
±
4.8 0.001
Re-operation for bleeding (%)
0.6
0.4
0.86
Peri-operative MI (%)
1.9
2.1
0.92
Stroke,
n
(%)
26, 1.73
9, 1.8
0.92
30-day mortality,
n
(%)
24, 1.6
7, 1.4
0.91
Mean
±
SD, mean
±
standard deviation; IABP, intra-aortic balloon counter pulsation;
LITA, left internal thoracic artery; LAD, left anterior coronary artery; ICU, intensive care
unit; CVE, cerebrovascular events; AF, atrial fibrillation.
TABLE 3. RISK FACTORS FOR STROKEAFTER CABG IN
MULTIVARIATE LOGISTICANALYSIS
Parameters
Stroke patients
(
n
=
35)
Populatıon
(
n
=
2000)
p
-value
Age (mean
±
SD)
65.26
±
21.4 63.85
±
5.72 0.14
LMCA disease (%)
17.9
18.4
0.85
IABP use (%)
1.23
1.15
0.925
Time of perfusion (min) (mean
±
SD)
79.65
±
48.12 71.15
±
24.12 0.001
Time of cross clamp (min) (mean
±
SD) 48.75
±
29.12 36.14
±
65 0.001
Post-operative hypotension (%)
79.8
12.4
0.001
Peripheral vascular disease (%)
74
16.5
0.001
Hypertension (%)
72
44.6
0.001
Smoking (%)
24
56.7
0.001
AF (%)
35
22.6
0.001
Dyslipidaemia (%)
68
94.5
0.001
DM (%)
67
86.7
0.001
CRF (%)
3.9
4.3
0.792
LVEF (mean
±
SD)
38.27
±
26.31 46.12
±
12.31 0.001
Mean
±
SD, mean
±
standard deviation; LMCA, left main coronary artery; IABP,
intra-aortic balloon counter pulsation; AF, atrial fibrillation; DM, diabetes mellitus;
CRF, chronic renal failure; LVEF, left ventricular ejection fraction.
