Heart rate at hospital discharge in patients with heart failure is associated with mortality and rehospitalization

Background--Whether heart rate upon discharge following hospitalization for heart failure is associated with long-term adverse outcomes and whether this association differs between patients with sinus rhythm (SR) and atrial fibrillation (AF) have not been well studied. Methods and Results--We conducted a retrospective cohort study from clinical registry data linked to Medicare claims for 46 217 patients participating in Get With The Guidelines-Heart Failure. Cox proportional-hazards models were used to estimate the association between discharge heart rate and all-cause mortality, all-cause readmission, and the composite outcome of mortality/ readmission through 1 year. For SR and AF patients with heart rate <75, the association between heart rate and mortality (expressed as hazard ratio [HR] per 10 beats-per-minute increment) was significant at 0 to 30 days (SR: HR 1.30, 95% CI 1.22 to 1.39; AF: HR 1.23, 95% CI 1.16 to 1.29) and 31 to 365 days (SR: HR 1.15, 95% CI 1.12 to 1.20; AF: HR 1.05, 95% CI 1.01 to 1.08). Similar associations between heart rate and all-cause readmission and the composite outcome were obtained for SR and AF patients from 0 to 30 days but only in the composite outcome for SR patients over the longer term. The HR from 0 to 30 days exceeded that from 31 to 365 days for both SR and AF patients. At heart rates <75, an association was significant for mortality only for both SR and AF patients.Conclusions: Among older patients hospitalized with heart failure, higher discharge heart rate was associated with increased risks of death and rehospitalization, with higher risk in the first 30 days and for SR compared with AF.