Aims: High resting heart rate (HR ≥70 b.p.m.) is associated with worse clinical outcomes in heart failure with reduced ejection fraction (HFrEF). Heart rate, guideline-directed medical therapy (GDMT) with beta-blocker (BB), and cardiovascular outcomes were evaluated in a large integrated health network.
Methods and results: Using electronic health records we examined patients with chronic HFrEF (ejection fraction ≤35%) in sinus rhythm with at least 1 year of follow-up and available serial HR and medication data between 1 January 2000 and 31 December 2014. Among 6071 patients followed for median of 1330 days across 73 586 total visits, median HR remained stable over time with 61.2% of the follow-up period with HR ≥70 b.p.m. At baseline, 27.9% of patients were on ≥ 50% GDMT target BB dose, 16.2% subjects at baseline, and 19.4% at the end of follow-up had HR ≥70 b.p.m. despite receiving ≥50% of target BB dose. In adjusted analyses, baseline HR was associated with all-cause mortality/heart failure (HF) hospitalization (hazard ratio 1.28 per 15 b.p.m. Heart rate increase; P < 0.001). In comparison, hazard ratio for BB dose was 0.97 (per 77.2 mg increase; P = 0.36). When evaluating patients based on HR and BB dose there was a significant difference in the cumulative hazard for all-cause mortality or HF hospitalization (P < 0.001). For HF hospitalization, hazard appeared to be more closely associated with HR rather than BB dose (P = 0.01).
Conclusion: In a real-world analysis, high resting HR was common in HFrEF patients and associated with adverse outcomes. Opportunities exist to improve GDMT and achieve HR control.