Elevated heart rate at discharge may be associated with adverse outcomes, readmissions in heart failure patients

Heart failure patients with elevated heart rates at hospital discharge may be at higher risk for all-cause and cardiovascular mortality and for 30-day readmission for heart failure and cardiovascular disease, according to a new study.

Researchers looked at whether heart rate at hospital discharge was associated with mortality at 30 days and 1 year or with outcomes after hospitalization. They used data from the EFFECT-HF trial, a population-based retrospective chart review of patients at least 18 years of age who were admitted to acute care hospitals with heart failure in Ontario, Canada, from 1999 to 2001 and 2004 to 2005.

Patients were included in the current study if they met the modified Framingham heart failure criteria at presentation, if their discharge summary included a primary diagnosis of heart failure, and if they remained in normal sinus rhythm while they were hospitalized. All-cause 30-day and 1-year mortality were the primary outcomes. Secondary outcomes included cardiovascular death and readmission for heart failure, ischemic heart disease and cardiovascular disease. Results were published early online Dec. 2 by Circulation: Heart Failure.

Overall, 9,097 patients with heart failure were included in the study, almost half of whom (47.1%) were men. Patients were classified as having discharge heart rates of 40 to 60 beats/min (n=1,333), 61 to 70 beats/min (n=2,170), 71 to 80 beats/min (n=2,631), 81 to 90 beats/min (n=1,700) or greater than 90 beats/min (n=1,263).

Compared with the reference group (61 to 70 beats/min), those with discharge heart rates in the 2 highest categories had significantly increased all-cause 30-day mortality (adjusted odds ratios, 1.59 for 81 to 90 beats/min and 1.56 for >90 beats/min; P=0.003 and 0.007, respectively). Patients in these 2 categories also had a higher risk for cardiovascular death at 30 days (adjusted odds ratios, 1.59 and 1.65, respectively; P=0.017 for both comparisons).

The highest heart rate, over 90 beats/min, was also associated with higher cardiovascular death and all-cause mortality at 1 year (adjusted odds ratios, 1.47 and 1.41; P=0.005 and <0.001, respectively) compared with the reference category of 40 to 60 beats/min. Those in the highest heart rate category also had more 30-day readmissions for heart failure and cardiovascular disease (adjusted hazards ratios, 1.26 and 1.29; P=0.0021 and 0.004, respectively).

The authors noted that their study did not prove causality and that discharge heart rates were determined from a single reading, among other limitations. However, they concluded that higher heart rates at discharge in heart failure patients were associated with higher risk for all-cause and cardiovascular death for 1 year, as well as a higher risk for readmission for heart failure and cardiovascular disease within 30 days.

“Our study suggests that heart rate, an eminently modifiable prognostic marker, merits attention in the transition from hospital to ambulatory care in the community,” the authors wrote. “Future studies are needed to define the beneficial impacts of both pharmacologic and non-pharmacologic heart rate lowering interventions and to determine if target ranges exist to guide therapy.”