Cardiovascular Journal of Africa: Vol 26 No 3 (May/June 2015)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 26, No 3, May/June 2015 132 AFRICA
In the present study, while the number of COPD patients was
higher in the older group, the number of diabetes mellitus patients
was lower than in the younger group. In addition, EuroSCORE
values were higher in elderly patients. The mortality rate was
higher in elderly patients; however, there were no statistically
significant differences between the patients who had emergency
surgery in both groups.
It has been reported that IABP decreases the mortality rates
of low cardiac output and severe myocardial ischaemia patients
in the pre-operative period, provides support for patients who
failed to wean from CPB during the intra-operative period,
and prevents low cardiac output and medically refractory
arrhythmias in ICU in the postoperative period.11,12 In this study,
IABP was used in cases of low cardiac output, persistent angina
pectoris, or arrhythmia due to myocardial ischaemia in the
pre-operative period.
In previous studies, the use of pre-operative IABP in high-risk
patients was reportedly more advantageous than peri-operative
IABP support. Böning et al. compared the use of pre-operative
and peri-operative IABP in high-risk patients in their study.
Their results indicate that the pre-operative use of IABP was
advantageous for early and long-term mortality.13
Dyub et al. showed that in a meta-analysis involving 1 034
patients, the use of pre-operative IABP in high-risk patients
reduced mortality.14 Holman et al. reported that when shock,
urgent surgery, haemodynamic instability, and MI in the last
three days were excluded, the use of pre-operative IABP did not
have a positive effect on morbidity and mortality rates; however,
the length of the hospital stay was less in these patients.15
Miceli et al. proposed a scoring system that predicts the need
for IABP support in high-risk CABG patients.16 According to
this study, heart failure, re-operations, emergency operations,
left main coronary artery disease, patients over the age of 70
years, moderate and poor left ventricular function, and recent
myocardial infarctions are independent risk factors for the need
for IABP support. As a result of the study, the benefits of IABP
support in patients with high-risk scores were emphasised. In
our clinical practice, we did not use a risk-scoring system for
prophylactic IABP support. In this study, we aimed to determine
the pre-operative risk factors for mortality and other clinical
outcomes.
In previous studies, emergency surgery, a history of myocardial
infarction, prolonged CPB, and concomitant peripheral artery
occlusive disease were all found to be significant determinants
of mortality in primary isolated CABG patients.17 Furthermore,
risk-scoring systems were generated. We showed that the
mortality rate of the older patient group was higher than that
of the younger group. However, the logistic regression analysis
indicated that the only independent risk factor for mortality was
a prolonged CPB time.
In addition, subgroup analysis revealed different results. For
example, in the older patient group, chronic renal failure and
prolonged CPB were identified as factors affecting mortality rate.
In young patients, female gender, diabetes mellitus, emergency
operations, higher EuroSCORE values, prolonged CPB, and
prolonged stays in the ICU were independent risk factors for
mortality. In elective operations advanced patient age and
Table 3. Parameters of patients who survived or died
Patients who
survived
(n = 133)
Patients who
died
(n = 57) p-value
Pre-operative MI, n (%) 40 (30) 15 (26.3) 0.601
BMI (kg/m2 ) 27.5 ± 4.2 26.9 ± 4 0.507
EuroSCORE 4.2 (0–10) 5.1 (0-10) 0.030
DM, n (%) 47 (35.3) 24 (42.1) 0.377
CRF, n (%) 3 (2.2) 5 (8.7) 0.040
Mean EF (%) 38.4 ± 8 37.5 ± 9 0.562
Mean age (years) 61.8 ± 9.8 64.9 ± 10 0.051
Older patients, n (%) 58 (43.6) 34 (59.6) 0.043
Gender (M:F) 33/101 20/37 0.118
COPD, n (%) 12 (9) 6 (10.5) 0.746
Emergency operation, n (%) 19 (14.2) 15 (26.3) 0.047
LMCA, n (%) 8 (6) 5 (8.7) 0.490
CVA, n (%) 5 (3.7) 4 (7) 0.333
HT, n (%) 69 (51.8) 34 (59.6) 0.328
Re-operation, n (%) 3 (2.2) 0 0.555
Pre-operative IABP, n (%) 14 (10.5) 3(2.2) 0.405
CPB time (min) 130 ± 48 167 ± 72 < 0.001
Cross-clamp time (min) 87 ± 35 94 ± 36 0.180
CPB time: cardiopulmonary bypass time, COPD: chronic obstructive
pulmonary disease, CRF: chronic renal failure, HT: hypertension,
DM: diabetes mellitus, CVA: previous cerebrovascular accident, BMI:
body mass index, LMCA: left main coronary artery disease.
Table 4. Factors for mortality in subgroup analysis
Younger group Older group
Odds ratio p-value Odds ratio p-value
COBD 0.035 0.851 0.015 0.903
CRF 0.168 0.682 4.205 0.040
Re-operation 0.949 0.330 - -
EF (%) 0.865 0.352 0.110 0.759
Age (years) 0.122 0.727 1.034 0.741
EuroSCORE 14.555 0.000 8.418 0.309
CPB time (min) 7.698 0.006 0.471 0.004
Cross-clamp time (min) 2.048 0.152 1.542 0.493
BMI (kg/m2) 0.703 0.402 0.384 0.214
Emergency operation 5.401 0.020 0.400 0.536
Female gender 8.850 0.003 1.725 0.527
HT 2.007 0.157 0.095 0.189
MI 0.427 0.513 0.004 0.758
DM 7.477 0.006 0.560 0.949
ICU time 4.947 0.026 0.038 0.454
Levosimendan 0.228 0.633 0.131 0.845
CVA 1.634 0.201 0.021 0.717
LMCA 0.955 0.329 0.021 0.885
CPB time: cardiopulmonary bypass time, COPD: chronic obstruc-
tive pulmonary disease, CRF: chronic renal failure, HT: hyperten-
sion, DM: diabetes mellitus, ICU: intensive care unit, CVA: previous
cerebrovascular accident, BMI: body mass index, LMCA: left main
coronary artery disease.
Table 5. IABP complications according to patient group
Younger group Older group p-value
Bleeding, n (%) 1 (1) 4 (4.3) 0.200
Arterial injury, n (%) 0 2 (2.1) 0.233
Mild thrombocytopenia, n (%) 10 (10.2) 15 (16.3) 0.309
Extremity ischaemia, n (%) 1 (1) 2 (2.1) 0.611
Total, n (%) 12 (12.2) 23 (25) 0.023