Cardiovascular Journal of Africa: Vol 27 No 6 (November/December 2016)

11 / 76

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 6, November/December 2016 AFRICA 341
aortic aneurysms died within five years of the diagnosis.9
Aortic surgeries are complex and have high morbidity and
mortality rates. The risks of surgery include paraplegia, stroke,
bleeding and death; however rupture, dissection and death
may also occur when the aneurysm is left unoperated. If
no intervention is done at the time of cardiac surgery, the
aneurysm may develop and rupture, and will need a second
open-heart procedure, with additional technical challenges and
complications. An initial concomitant surgery may increase the
operative risks but protects patients from long-term aneurysmatic
complications.
Replacement of ascending aortic aneurysms often requires
significant additional surgery, such as CABG and AVR. Severe
aortic valve disease is occasionally associated with dilation of the
Table 6. Potential risk factors associated with mortality in the multivariate logistic regression equation
Variables B SE Wald Sig Exp (B)
95% CI for exp (B)
Lower Upper
STEP 1a (beginning model)
Constant –5.23 1.587 10.844 0.001 0.005
Age (≥ 70 years) 1.146 0.732 2.452 0.117 3.144 0.750 13.190
Additional operations
AVR 0.945 1.246 0.575 0.448 2.573 0.224 29.606
CABG 0.540 1.272 0.180 0.671 1.716 0.142 20.752
AVR+CABG 1.013 1.434 0.499 0.480 2.755 0.166 45.761
Bentall 0.088 1.426 0.004 0.951 1.092 0.067 17.856
DM (yes) 0.573 0.767 0.559 0.455 1.774 0.395 7.971
Inotrope use (yes) 2.510 1.134 4.899 0.027 12.308 1.333 113.645
IABP (yes) 2.173 0.881 6.091 0.014 8.789 1.564 49.379
STEP 4 (final model)
Constant –3.87 1.028 14.154 < 0.001 0.021
Inotrope use (yes) 2.280 1.078 4.471 0.034 9.779 1.181 80.947
IABP (yes) 2.200 0.770 8.177 0.004 9.029 1.998 40.797
aVariable(s) entered on step 1: age, additional operations, DM, inotrope use, ABP.
AVR: aortic valve replacement, CABG: coronary arterial bypass grefting COPD: chronic obstructive pulmonary disease, DM: diabetes mellitus, PAD: peripheral arte-
rial disease, IABP: intra-aortic balloon pump.
Table 5. Potential risk factors associated with mortality in the univariate logistic regression equation
Variable No Total no
Prevalence
(%) B SE Wald Sig Exp (B)
95% CI for exp (B)
Lower Upper
Constant –1.72 0.280 37.774 < 0.001 0.179
Age (years)
< 70 8 69 11.6
≥ 70 7 30 23.3 0.842 0.572 2.162 0.141 2.321 0.756 7.127
Gender
Female 5 39 12.8
Male 10 60 16.7 0.307 0.591 0.271 0.603 1.360 0.427 4.332
Additional operations
No 1 19 5.3 4.815 0.307
AVR 4 36 11.1 0.811 1.156 0.492 0.483 2.250 0.233 21.694
CABG 5 25 20.0 1.504 1.143 1.733 0.188 4.500 0.479 42.248
AVR+CABG 3 8 37.5 2.380 1.261 3.564 0.059 10.800 0.913 127.754
Bentall 2 11 18.2 1.386 1.291 1.153 0.283 4.000 0.319 50.229
COPD
No 13 89 14.6
Yes 2 10 20.0 0.379 0.846 0.201 0.654 1.462 0.279 7.667
PAD
No 14 94 14.9
Yes 1 5 20.0 0.357 1.155 0.095 0.757 1.429 0.149 13.741
DM
No 9 74 12.2
Yes 6 25 24.0 0.824 0.588 1.966 0.161 2.281 0.720 7.221
Inotrope use
No 1 42 2.4
Yes 14 57 24.6 2.591 1.058 6.001 0.014 13.349 1.679 106.145
IABP
No 9 89 10.1
Yes 6 10 60.0 2.590 0.735 12.419 < 0.001 13.333 3.157 56.312
AVR: aortic valve replacement, CABG: coronary arterial bypass grafting, COPD: chronic obstructive pulmonary disease, DM: diabetes mellitus, PAD: peripheral arte-
rial disease, IABP: intra-aortic balloon pump.