Early administration of ivabradine in patients admitted for acute decompensated heart failure

Heart Rate Reduction and the Prognosis of Heart Failure Focused on Ivabradine

Cardioprotective medications referred to as the fantastic four are used to treat heart failure (HF). Additionally, ivabradine can also be used if the heart rate (HR) is elevated. An elevated HR is a prognostic factor in HF patients, as well as in the general population. In both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), an elevated HR is associated with all-cause mortality, whereas cardiovascular death is only associated with the former. In addition, previous clinical trials revealed that ivabradine was useful only in HFrEF but not in HFpEF. Therefore, ivabradine is indicated for patients only with HFrEF. Moreover, ivabradine increases the stroke volume by ensuring an effective diastolic time as a result of the decreased HR. Including this effect, the introduction of ivabradine allowed for the discontinuation of dobutamine infusion used in HF patients and the uptitration of β-blockers in other reports. Additionally, ivabradine improves exercise tolerance and the subjective symptoms of HF. However, the effects of ivabradine on exercise tolerance remain poorly understood, and prospective clinical trials are underway. While these beneficial effects have been reported, side effects such as photopsia and atrial fibrillation have also been reported. It is important to use ivabradine appropriately in conjunction with standard HF treatment, including quadruple therapy.

Evaluating the role of ivabradine in acute decompensated heart failure: A systematic review and meta-analysis

BACKGROUND

Acute decompensated heart failure (ADHF) presents a significant global health challenge, with high morbidity, mortality, and healthcare costs. The current therapeutic options for ADHF are limited. Ivabradine, a selective inhibitor of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, has emerged as a potential therapy for ADHF by reducing the heart rate (HR) without negatively affecting myocardial contractility. However, the evidence regarding the efficacy and safety of ivabradine in patients with ADHF is limited and inconsistent. This meta-analysis aimed to evaluate the efficacy and safety of ivabradine for ADHF based on observational studies.

METHODS

A systematic literature search was conducted following PRISMA guidelines to identify relevant observational studies comparing ivabradine with placebo in adult patients with ADHF. Data were pooled using a random-effects model, and heterogeneity was assessed. The risk of bias was evaluated using the Newcastle-Ottawa Scale.

RESULTS

Four observational studies comprising a total of 12034 patients. Meta-analysis revealed that ivabradine significantly reduced all-cause mortality (RR: 0.66, 95 % CI: 0.49-0.89, p < 0.01) and resting HR (MD: -12.54, 95 % CI: -21.66-3.42, p < 0.01) compared to placebo. However, no significant differences were observed in cardiovascular mortality, hospital readmission for all causes, changes in LVEF, or changes in LVEDD. Sensitivity and publication bias assessments were conducted for each outcome.

CONCLUSION

Ivabradine may be beneficial for reducing mortality and HR in patients with ADHF. However, its impact on other clinical outcomes such as cardiovascular mortality, hospital readmission, and cardiac function remains inconclusive. Further research, particularly well-designed RCTs with larger sample sizes and longer follow-up durations, are warranted.

Clinical Implications of Ivabradine in the Contemporary Era

Ivabradine is a recently introduced inhibitor of the If ion channel, which exhibits the capacity to reduce heart rate while preserving hemodynamic stability. At present, ivabradine finds its clinical indication in patients suffering from heart failure with reduced ejection fraction and maintaining a relative sinus rhythm refractory to beta-blockers. To optimize heart rate control, it is recommended to pursue an aggressive up-titration of ivabradine. This approach may ameliorate tachycardia-induced hypotension by incrementally enhancing cardiac output and allow further up-titration of agents aimed at ameliorating heart failure, such as beta-blockers. Both the modulation of heart rate itself and the up-titration of agents targeting heart failure lead to cardiac reverse remodeling, consequently culminating in a subsequent reduction in mortality and morbidity. A novel overlap theory that our team proposed recently has emerged in recent times. Under trans-mitral Doppler echocardiography, the E-wave and A-wave closely juxtapose one another without any overlapping at the optimal heart rate. Employing echocardiography-guided ivabradine for heart-rate modulation to minimize the overlap between the E-wave and A-wave appears to confer substantial benefits to patients with heart failure. This approach facilitates superior cardiac reverse remodeling and yields more favorable clinical outcomes when compared to those patients who do not receive echocardiography-guided care. The next pertinent issue revolves around the potential expansion of ivabradine's clinical indications to encompass a broader spectrum of diseases. It is imperative to acknowledge that ivabradine may not yield clinically significant benefits in patients afflicted by heart failure with preserved ejection fraction, acute heart failure, sepsis, or stable angina. An important fact yet to be explored is the clinical applicability of ivabradine in patients with atrial fibrillation, a concern that beckons future investigation. In this review, the concept of overlap theory it introduced, along with its application to expand the indication of ivabradine and the overlap theory-guided optimal ivabradine therapy.

Ivabradine in patients with heart failure: a systematic literature review

Background: Heart failure is a chronic disease linked with significant morbidity and mortality, and uncontrolled resting heart rate is a risk factor for adverse outcomes. This systematic literature review aimed to assess the efficacy, safety, and patient-reported outcomes (PROs) of ivabradine in patients with heart failure (HF) with reduced ejection fraction (HFrEF) in randomized controlled trials (RCTs) and observational studies. Methods: We searched electronic databases from their inception to July 2021 to include studies that reported on efficacy, safety, or PROs of ivabradine in patients with HFrEF. Results: Of 1947 records screened, 51 RCTs and 6 observational studies were identified. Ivabradine on top of background therapy demonstrated a significant reduction in composite outcomes including hospitalization for HF or cardiovascular death. In addition, observational studies suggested that ivabradine was associated with a significant reduction in mortality. Across all studies, ivabradine use on top of background therapy was associated with greater reductions in heart rate, improved EF, and improved health-related quality of life (QoL) and comparable risk of total adverse events compared to those treated with background therapy alone. Conclusions: Ivabradine on top of background therapy is beneficial for heart rate, hospitalization risk for HF, mortality, EF, and patients' QoL. Moreover, these benefits were achieved with no significant increase in the overall risk of total adverse events.