Heart failure survival score continues to predict clinical outcomes in patients with heart failure receiving β-blockers

Abstract 

Background

The Heart Failure Survival Score (HFSS) has been previously shown to effectively risk-stratify patients under evaluation for heart transplantation. However, this model was developed before broad use of beta blockade. We hypothesized that the prognostic tool would retain its ability to risk stratify patients treated with β-blockers.

Methods

We collected clinical data on 524 consecutive patients referred for heart transplantation from 1994 to 2001. Kaplan-Meier survival analysis and multivariable Cox regression analysis were performed with events defined as death, left ventricular assist device placement, or United Network of Organ Sharing 1 heart transplantation.

Results

Kaplan-Meier analysis of the patient population revealed effective discrimination by the survival score both for β-blocker treated and untreated patients (both p < 0.0001). Two-year event-free survival was 94% ± 2% and 84% ± 4% for β-blocker and no β-blocker patients in the low-risk HFSS strata. Cox proportional hazard modeling showed that HFSS strata (medium risk: HR 2.65, 95% CI 1.75–4.02, p < 0.001; high risk: HR 5.51, 95% CI 3.64–8.33, p < 0.001) and β-blocker treatment (HR 0.45, 95% CI 0.31–0.64, p < 0.001) were significant predictors of event-free survival. Receiver operating curves (area under the curve) for HFSS strata used to predict 2-year events were similar for β-blocker treated (0.78 ± 0.04) and untreated (0.80 ± 0.03) patients.

Conclusions

The HFSS provides effective risk stratification with or without β-blocker therapy. Consideration of β-blocker therapy with survival score strata improves outcome prediction in patients evaluated for heart transplantation.