Thirty-day Mortality
Thirty-day mortality was 7.1% for the whole cohort, while 100% for the
acute phase (<7 days after AMI12), 21.4%
for the healing phase (7–28 days), and 4.08% for the healed phase (29
days and beyond). Significant risk factors of 30-day mortality found by
the univariable analysis were age, gender, infarction-surgery interval,
previous cerebrovascular accident, ΔD, and ΔDR. (Table 3) Independent
risk factors of 30-day mortality found by
multivariable analysis corrected by
1,000 bootstrap replicates were female gender, elder age, shorter
infarction-surgery interval, previous cerebrovascular accident, lower
ΔD, and higher ΔDR. (Table 4)
ROC curves for Dmax and ΔDR were
plotted separately to evaluate their predictive power for
30-day mortality, yielding an area
under the curve (AUC) of 0.641 and 0.863 respectively. (Figure 1) The
results indicated that ΔDR predicted 30-day mortality with high
accuracy.
The cut-off point was picked at 0.205 mm/d by calculating the maximum of
the Youden index. According to the cut-off point, the patients were
divided into the low ΔDR group and the high ΔDR group. The differences
in preoperative IABP implantation, EuroSCORE, preoperative critical
status, CPB time, aortic clamp time, postoperative ventilation time, ICU
stay, reoperation, and 30-day mortality were statistically significant
between the two groups. (Table 5)