Characterizing patients with chronic heart failure in community care after hospitalization: a potential role for ivabradine

Resting heart rate in ambulatory heart failure with reduced ejection fraction treated with beta-blockers

AIMS

Current guidelines recommend beta-blocker therapy in chronic heart failure with reduced ejection fraction (HFrEF) titrated according to tolerated target dose. The efficiency of this strategy to obtain adequate heart rate (HR) control remains unclear in clinical practice. The aim of this study was to determine, in a real-world setting, the proportion of HFrEF patients who fail to achieve beta-blocker target doses, whether target doses of beta-blockers have a relationship with the adequacy in reducing resting HR over time.

METHODS AND RESULTS

Beta-blocker dose and resting HR of consecutive ambulatory patients with a diagnosis of HFrEF (ejection fraction ≤ 35%) in sinus rhythm were reviewed at the first outpatient contact in the Cleveland Clinic Health System from the year 2000 to 2015. Patients who did not receive beta-blocker therapy, have congenital heart disease and hypertrophic cardiomyopathy, were not in sinus rhythm, or have a history of heart transplant were excluded. Patients were followed up until their last known visit at the Cleveland Clinic. Median resting HR was 71 b.p.m. [inter-quartile range (IQR) 60-84 b.p.m.] in 8041 patients (median age 65; 68% male) with 67% on carvedilol, 32% on metoprolol succinate, and 1% on bisoprolol. In 3674 subjects (56%), resting HR was ≥70 b.p.m. At final follow-up after a median of 21 months (IQR 0.1-7.2 years), resting HR was 72 b.p.m. (IQR 60-84 b.p.m.) in the subset of patients with persistently low ejection fraction ≤ 35%. HR ≥ 70 b.p.m. was observed in 55% of this group. Beta-blocker target dose was achieved in 19%, 5%, and 15% of those receiving carvedilol, metoprolol succinate, and bisoprolol, respectively. In the subset of patients who experienced beta-blocker up-titration, reduced mortality or hospitalization due to heart failure was observed in patients who experienced the lowest HR after titration.

CONCLUSIONS

In our single-centre experience, the majority of patients with chronic HFrEF treated with beta-blocker therapy did not achieve target doses over time, and a substantial proportion had inadequate control of resting HR. There was no relationship between achieved beta-blocker target dose and resting HR control.

Is There a Role for Ivabradine in the Contemporary Management of Patients with Chronic Heart Failure in Academic and Community Heart Failure Clinics in Canada?

INTRODUCTION

In patients with heart failure (HF) and reduced ejection fraction, increased heart rate (HR) is an independent risk factor for adverse outcomes. In systolic HF treatment with the If inhibitor ivabradine trial (SHIFT), Ivabradine improved survival when added to conventional treatment including β-blockers. However, the extent of benefit in the real world is unclear. We examined the characteristics of patients on guideline-directed therapy and determined who had SHIFT-like characteristics.

METHODS

A total of 1096 patients with chronic HF were reviewed from June 2014 to April 2015 in two HF clinics in Toronto: an academic institution (AI), and a community hospital (CH) clinic. SHIFT-like characteristics [left ventricular ejection fraction (LVEF) ≤35%; sinus rhythm; and HR ≥ 70 bpm] were described.

RESULTS

For all patients, mean age was 75 ± 13 years, overall LVEF was 44 ± 15%, AI less than CH (41.9 ± 14.0% vs. 45.7 ± 15.0%; p < 0.0001). More than two-thirds of patients in both groups were on β-blockers; with less than one-third at target dose. The proportion of patients with SHIFT-like characteristics was 8.4% AI and 11.7% CH, respectively (p = 0.0658).

CONCLUSION

In HF clinics from both academic and community hospitals in Toronto, up-titration in the dose of β-blockers and other guideline therapy can be improved on. A small proportion of patients with HF and SHIFT-like characteristics may potentially benefit from the addition of Ivabradine, just approved in Canada; this number will be further reduced if target dosage for β-blockers is achieved.

FUNDING

Servier Inc.

Addressing Major Unmet Needs in Patients with Systolic Heart Failure: The Role of Ivabradine

We reviewed clinical evidence for the use of ivabradine in systolic heart failure (HF), in which it appears to improve symptoms, improve quality of life, prevent hospitalization, and prolong survival, thereby addressing unmet needs in the management of HF. Ivabradine provides symptomatic benefits in HF on top of standard therapies, in terms of functional parameters and exercise capacity, and there is some evidence that this leads to improvements in quality of life in symptomatic HF patients, who may have dyspnea, altered exercise capacity, and fatigue. The SHIFT trial demonstrated that ivabradine has significant beneficial effects on major outcomes in HF. Ivabradine had a significant effect on pump failure death, which was reduced by 26 % (p = 0.014), with no effect on sudden cardiac death. This is an important result since pump failure death is currently the main cause of death in HF, and also because the reductions in mortality obtained with beta-blockers and spironolactone in the last 20 years appear to be mainly due to reduction in sudden death rather than reduction in pump failure death. Ivabradine also has a beneficial effect on hospital admissions (-26 %, p < 0.0001), which is clinically relevant since a quarter of HF patients can expect to be readmitted to hospital for HF within 1 month of discharge. Ivabradine-treated patients are also at significantly lower risk of experiencing a second or third hospitalization for worsening HF. Ivabradine clearly has a key role to play in the management of HF by covering the main therapeutic objectives of symptoms, quality of life, and outcomes.

Relation of Elevated Heart Rate in Patients With Heart Failure With Reduced Ejection Fraction to One-Year Outcomes and Costs

There are limited data describing outcomes associated with an elevated heart rate in patients with heart failure with reduced ejection fraction (HFrEF) in routine clinical practice. We identified patients with HFrEF at Duke University Hospital undergoing echocardiograms and heart rate assessments without paced rhythms or atrial fibrillation. Outcomes (all-cause mortality or hospitalization and medical costs per day alive) were assessed using electronic medical records, hospital cost accounting data, and national death records. Patients were stratified by heart rate (<70 and ≥70 beats/min) and compared using generalized linear models specified with gamma error distributions and log links for costs and proportional hazard models for mortality/hospitalization. Of 722 eligible patients, 582 patients (81%) were treated with β blockers. The median heart rate was 81 beats/min (25th and 75th percentiles 69 to 96) and 527 patients (73%) had a heart rate ≥70 beats/min. After multivariate adjustment, a heart rate ≥70 beats/min was associated with increased 1-year all-cause mortality or hospitalization, hazard ratio 1.37 (95% CI 1.07 to 1.75) and increased medical costs per day alive, cost ratio 2.03 (95% CI 1.53 to 2.69). In conclusion, at a large tertiary care center, despite broad use of β blockers, a heart rate ≥70 beats/min was observed in 73% of patients with HFrEF and associated with worse 1-year outcomes and increased direct medical costs per day alive.

Ivabradine in Management of Heart Failure: a Critical Appraisal

Elevated resting heart rate has been linked to poor outcomes in patients with chronic systolic heart failure. Blockade of funny current channel with ivabradine reduces heart rate without inotropic effects. Ivabradine was recently approved by US Food and Drug Administration for patients with stable, symptomatic chronic heart failure (HF) with left ventricular ejection fraction (LVEF) ≤35 %, who are in sinus rhythm with resting heart rate (HR) ≥ 70 bpm and either are on maximally tolerated doses of beta-blockers, or have a contraindication to beta-blockers. This article will review and evaluate the data supporting the use of ivabradine in patients with HF and explore its mechanisms and physiologic effects.