Long-Term Survival
Median follow up was 2.28 years (IQR 0.04 to 4.50 years). One- and
five-year unadjusted actuarial survival was 56.1% and 43.0% for the
entire cohort, respectively (Figure 1A ). Figure 1Bdisplays unadjusted survival, stratified by mechanism of MCS. In this
analysis, patients were categorized by the highest level of support used
(ECMO > Impella > IABP). At one and five
years, actuarial survival was highest in patients bridged with an
Impella device and lowest in patients bridged with ECMO.
Cox proportional hazards modeling was performed to identify predictors
of mortality in patients bridged with MCS from CBP. In a univariable
analysis, postoperative IABP insertion (HR 1.45, 95% CI 1.00 to 2.10,
P=0.05), and either intraoperative (HR 1.59, 95% CI 1.12 to 2.26,
P<0.001) or postoperative (HR 2.52, 95% CI 1.82 to 3.49,
P<0.001) ECMO insertion were associated with increased hazards
for mortality. Usage of an Impella device, either intraoperatively (HR
0.54, 95% CI 0.23 to 1.32, P=0.18) or postoperatively (HR 0.90, 95% CI
0.37 to 2.17, P=0.81) was not found to be associated with mortality.
There were too few patients with durable ventricular assist device
insertion to model.
When adjusted for other significant baseline risk factors, postoperative
ECMO cannulation was associated with a five-fold increased hazards for
mortality in the final multivariable model (HR 5.12, 95% CI 2.04 to
12.85, P<0.001) (Table 5 ). Intraoperative ECMO
cannulation did not reach statistical significance for mortality hazard
(HR 2.47, 95% CI 0.96 to 6.33, P=0.06). Other factors associated with
increased hazards for mortality include increasing age (per year, HR
1.04, 95% CI 1.01 to 1.07, P=0.01), presence of peripheral vascular
disease (HR 3.55, 95% CI 1.93 to 6.52, P<0.001), and emergent
operative status (HR 5.90, 95% CI 1.89 to 18.44, P<0.001).
After risk adjustment, bridging with either Impella or IABP were not
found to be associated with mortality, and were removed from the final
model.