Heart rate awareness in patients with chronic stable heart failure. A multi-center observational study.

Aims: We assessed adherence to European Society of Cardiology heart rate guidelines (i.e. heart rates less than 70 bpm) in patients with chronic stable heart failure. We also investigated the percent of patients on target doses of rate controlling drugs.

Methods: Multicenter study involving 549 patients from 12 heart failure centers in the Republic of Ireland. Patients in sinus rhythm with stabilized heart failure treatment and without recent cardiac events were included. Resting heart rates, demographics, co-morbidities and heart failure therapies were recorded.

Results: Heart rates ≥ 70 bpm were noted in 176 (32.1%) patients with 117 (21.3%) having rates > 75 bpm. Non-achievement of target heart rates were unrelated to age, gender or most cardiovascular risk factors. However, 42% of patients with diabetes (p<0.01), 56% of those with COPD (p<0.0001) and 46% of those with NYHA Class 3 (p<0.05) did not achieve target heart rates. Fifty eight (11%) subjects were not on beta-blockers and of these forty subjects (69%) (p<0001) did not achieve target heart rates. Of those on beta-blockers only 25% were at target dose. However, beta-blocker dosage was unrelated to achieving target heart rates. Ivabradine was used in 11% of patients with 10% at target dosage.

Conclusion: This study highlights that a third of "stabilized" chronic heart failure patients have not reached recommended target heart rates. Respiratory problems, diabetes and marked dyspnea were associated with poorer rate control. Guideline unawareness, inadequate beta-blocker titration and under use of ivabradine may prevent patients gaining the proven benefits of heart rate control.