Ivabradine in acute heart failure: Effects on heart rate and hemodynamic parameters in a randomized and controlled swine trial

Hyperpolarization-activated cyclic nucleotide-gated channel inhibitor in myocardial infarction: Potential benefits beyond heart rate modulation

Myocardial infarction (MI) and its associated complications including ventricular arrhythmias and heart failure are responsible for a significant incidence of morbidity and mortality worldwide. The ensuing cardiomyocyte loss results in neurohormone-driven cardiac remodeling, which leads to chronic heart failure in MI survivors. Ivabradine is a heart rate modulation agent currently used in treatment of chronic heart failure with reduced ejection fraction. The canonical target of ivabradine is the hyperpolarization-activated cyclic nucleotide-gated channels (HCN) in cardiac pacemaker cells. However, in post-MI hearts, HCN can also be expressed ectopically in non-pacemaker cardiomyocytes. There is an accumulation of intriguing evidence to suggest that ivabradine also possesses cardioprotective effects that are independent of heart rate reduction. This review aims to summarize and discuss the reported cardioprotective mechanisms of ivabradine beyond heart rate modulation in myocardial infarction through various molecular mechanisms including the prevention of reactive oxygen species-induced mitochondrial damage, improvement of autophagy system, modulation of intracellular calcium cycling, modification of ventricular electrophysiology, and regulation of matrix metalloproteinases.

Relationship between Noise Exposure and Prognosis of Patients with Heart Failure: A Retrospective Analysis

BACKGROUND

Environmental noise damages the cardiovascular system and endangers human health. This study was conducted to analyze the relationship between noise exposure and prognosis of patients with heart failure and to provide a good strategy for disease treatment.

METHODS AND MATERIALS

This study was a retrospective analysis. A total of 487 patients with heart failure admitted to Ganzhou People's Hospital from September 2021 to September 2023 were selected as research subjects, and they were divided into the low noise exposure group (<55 dB; group A) and the high noise exposure group (≥55 dB; group B) according to the noise exposure conditions. The baseline data and physiological indicators of the two groups were analyzed.

RESULTS

In this study, 84 patients were included in group B, and the remaining 403 patients were included in group A. Group A had lower systolic pressure, diastolic pressure, heart rate, and respiratory rate compared to group B (P < 0.05). The serum B-type natriuretic peptide (BNP) level in group A was lower than that in group B (P < 0.001). Group B had significantly higher scores on the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) compared to group A (P < 0.001). The noise level was correlated with SAS score, SDS score, and serum BNP level (all P < 0.001).

CONCLUSION

The noise exposure is correlated with the prognosis of patients with heart failure, suggesting that active strategies should be adopted to reduce the impact of noise on their disease.

Successful treatment with ivabradine in a β-blocker-refractory patient with acute decompensated heart failure with reduced ejection fraction

Ivabradine is an established treatment for chronic heart failure with reduced ejection fraction (HFrEF); however, it is not used for acute heart failure treatment. Negative inotropic effects (NIE) often limit the up-titration of β-blockers. Contrarily, ivabradine has no NIE, and enables β-blockers usage for treating patients with acute decompensated HFrEF.

Therapeutic Use and Molecular Aspects of Ivabradine in Cardiac Remodeling: A Review

Cardiac remodeling can cause ventricular dysfunction and progress to heart failure, a cardiovascular disease that claims many lives globally. Ivabradine, a funny channel (I_f) inhibitor, is used in patients with chronic heart failure as an adjunct to other heart failure medications. This review aims to gather updated information regarding the therapeutic use and mechanism of action of ivabradine in heart failure. The drug reduces elevated resting heart rate, which is linked to increased morbidity and mortality in patients with heart failure. Its use is associated with improved cardiac function, structure, and quality of life in the patients. Ivabradine exerts several pleiotropic effects, including an antiremodeling property, which are independent of its principal heart-rate-reducing effects. Its suppressive effects on cardiac remodeling have been demonstrated in animal models of cardiac remodeling and heart failure. It reduces myocardial fibrosis, apoptosis, inflammation, and oxidative stress as well as increases autophagy in the animals. It also modulates myocardial calcium homeostasis, neurohumoral systems, and energy metabolism. However, its role in improving heart failure remains unclear. Therefore, elucidating its molecular mechanisms is imperative and would aid in the design of future studies.

Hemodynamic effects of heart rate lowering in patients admitted for acute heart failure: the RedRate-HF Study (Reduction of heart Rate in Heart Failure)

BACKGROUND

In patients admitted for acute heart failure (HF) indication for drugs which reduce the heart rate (HR) is debated. The multicentre prospective study Reduction of heart Rate in Heart Failure (RedRate-HF) was designed to analyse the hemodynamic effects of an early reduction of HR in acute HF.

METHODS

Hemodynamic parameters were recorded by using the bioimpedance technique, which was shown to be accurate, highly reproducible and sensitive to intra-observer changes. Lowering HR was obtained by ivabradine 5 mg bd, given 48-72 h after admission on the top of optimized treatment. Patients were followed at 24, 48, 72 h after drug assumption and at hospital discharge.

RESULTS

Twenty patients of a mean age of 67 ± 15 years, BNP at entry 1348 ± 1198 pg/ml were enrolled. Despite a clinical stabilization, after 48-72 h from admission, HR was persistently >70 bpm. Ivabradine was well tolerated in all patients with a significant increase in RR interval from 747 ± 69 ms at baseline to 948 ± 121 ms at discharge, P < 0.0001. Change in HR was associated with a significant increase in stroke volume (baseline 73 ± 22 vs. 84 ± 19 ml at discharge, P = 0.03), and reduction in left cardiac work index (baseline 3.6 ± 1.2 vs. 3.1 ± 1.1 kg/m2 at discharge, P = 0.04). Other measures of heart work were also significantly affected while cardiac output remained unchanged.

CONCLUSION

The strategy of an early lowering of HR in patients admitted for acute HF on top of usual care is feasible and safe. The HR reduction causes a positive increase in stroke volume and may contribute to saving energy without affecting cardiac output.

The role of ivabradine in doxorubicin-induced cardiotoxicity: exploring of underlying argument

This study investigated the potential role of ivabradine (IVN) in the attenuation of doxorubicin (DXR)-induced cardiotoxicity in rats. A total of 28 Swiss-Albino male mice were used, divided into four equal groups: the negative control did not receive any agents (n = 7), the DXR group received a single dose of DXR 20 mg/kg (n = 7), the treated group A was pretreated with IVN 5 mg/kg plus DXR (n = 7), and the treated group B was pretreated with IVN 10 mg/kg plus DXR (n = 7). The duration of this study was 10 days. Inflammatory biomarkers, including tumor necrosis factor alpha (TNF-α), lactate dehydrogenase (LDH), malondialdehyde (MDA), and cardiac troponin (cTn-I) serum levels were measured. TNF-α, LDH, MDA, and cTn-I serum levels were higher in the DXR-treated mice compared with the control (P˂0.01). IVN produced a dose-dependent effect in the reduction of MDA and cTn-I compared to DXR-treated mice (P˂0.05). Our findings suggest that IVN is an effective agent in mitigating DXR-induced cardiotoxicity due to its anti-inflammatory and antioxidant effects. IVN illustrated a dose-dependent effect in the attenuation of DXR-induced cardiotoxicity through inhibition of lipid peroxidation and cardiomyocyte injury.

Acute-phase administration of ivabradine supported by intra-aortic balloon pump induces myocardial recovery without significant haemodynamic worsening in a patient with acute fulminant myocarditis: a case report

Background

Ivabradine can reduce the heart rate without affecting myocardial contractility or vascular tone. Current guidelines recommend its use for treating patients with chronic heart failure who have a high heart rate (≥75 b.p.m.) and persistent symptoms despite guideline-directed therapy. Nonetheless, little is known about its efficacy in patients with acute cardiogenic shock. We report a case of successful treatment of cardiogenic shock

Case summary

A 53-year-old previously healthy man was admitted due to cardiogenic shock with acute fulminant myocarditis. The patient was placed on intra-aortic balloon pump support and was given guideline-directed therapy including inotropic agents and furosemide. However, no improvement was seen in haemodynamics and the patient was in sinus tachycardia (116 b.p.m.). On Day 2, ivabradine therapy was initiated to reduce the myocardial workload and stabilize the haemodynamic parameters. As heart rate decreased, his symptoms improved and urine output increased without affecting the blood pressure. Subsequently, the patient recovered from cardiogenic shock. The intra-aortic balloon pumping was discontinued on Day 7, and the patient was discharged on Day 22.

Discussion

Ivabradine has the potential to induce rapid cardiac recovery and haemodynamic improvement in the acute phase of heart failure if supported by intra-aortic balloon pump.

Effects of ivabradine on the prevention of intradialytic hypotension in a dialytic patient with heart failure with reduced ejection fraction

A 65-year-old man with a history of heart failure with reduced ejection fraction (HFrEF) and renal failure was admitted due to difficulty in fluid volume control during haemodialysis. He had frequent episodes of intradialytic hypotension (IDH) with presyncope during haemodialysis despite using a vasopressor agent. Before haemodialysis, his blood pressure was 130-150/60-70 mm Hg, and his heart rate was 80-100 beats/min. There were no specific causes of IDH. For refractory IDH, he was treated with oral ivabradine (2.5 mg two times per day), which resulted in reduced heart rate and decreased occurrence of IDH. This is the first report to describe a dialysis case with HFrEF presenting with an elevated heart rate and impaired fluid management as manifested by recurring IDH, which improved after ivabradine treatment. Ivabradine therapy may assist in increasing stroke volume by lowering the sinus heart rate, thus resulting in the prevention of IDH.

Protection of CAPE-pNO2 Against Chronic Myocardial Ischemia by the TGF-Β1/Galectin-3 Pathway In Vivo and In Vitro

Although it is known that caffeic acid phenethyl ester (CAPE) and its derivatives could ameliorate acute myocardial injury, their effects on chronic myocardial ischemia (CMI) were not reported. This study aimed to investigate the potential effect of caffeic acid p-nitro phenethyl ester (CAPE-pNO₂, a derivative of CAPE) on CMI and underlying mechanisms. SD rats were subjected to high-fat-cholesterol-diet (HFCD) and vitamin D₃, and the H9c2 cells were treated with LPS to establish CMI model, followed by the respective treatment with saline, CAPE, or CAPE-pNO₂. In vivo, CAPE-pNO₂ could reduce serum lipid levels and improve impaired cardiac function and morphological changes. Data of related assays indicated that CAPE-pNO₂ downregulated the expression of transforming growth factor-β1 (TGF-β1) and galectin-3 (Gal-3). Besides, CAPE-pNO₂ decreased collagen deposition, the number of apoptotic cardiomyocytes, and some related downstream proteins of Gal-3 in the CMI rats. Interestingly, the effects of CAPE-pNO₂ on TGF-β1, Gal-3, and other proteins expressed in the lung were consistent with that in the heart. In vitro, CAPE-pNO₂ could attenuate the fibrosis, apoptosis, and inflammation by activating TGF-β1/Gal-3 pathway in LPS-induced H9c2 cell. However, CAPE-pNO₂-mediated cardioprotection can be eliminated when treated with modified citrus pectin (MCP, an inhibitor of Gal-3). And in comparison, CAPE-pNO₂ presented stronger effects than CAPE. This study indicates that CAPE-pNO₂ may ameliorate CMI by suppressing fibrosis, inflammation, and apoptosis via the TGF-β1/Gal-3 pathway in vivo and in vitro.

Impact of ivabradine in decompensated heart failure due to cancer therapy-related cardiac dysfunction

In cases of decompensated heart failure related to cancer therapy-related cardiac dysfunction, ivabradine administration could lead to an increased stroke volume by reducing the sinus heart rate, resulting in favorable hemodynamics. Assessment of the overlap between the E- and A-waves facilitates understanding the effects of ivabradine in such cases.

Ivabradine Induces Cardiac Protection against Myocardial Infarction by Preventing Cyclophilin-A Secretion in Pigs under Coronary Ischemia/Reperfusion

In response to cardiac ischemia/reperfusion, proteolysis mediated by extracellular matrix metalloproteinase inducer (EMMPRIN) and its secreted ligand cyclophilin-A (CyPA) significantly contributes to cardiac injury and necrosis. Here, we aimed to investigate if, in addition to the effect on the funny current (I(f)), Ivabradine may also play a role against cardiac necrosis by reducing EMMPRIN/CyPA-mediated cardiac inflammation. In a porcine model of cardiac ischemia/reperfusion (IR), we found that administration of 0.3 mg/kg Ivabradine significantly improved cardiac function and reduced cardiac necrosis by day 7 after IR, detecting a significant increase in cardiac CyPA in the necrotic compared to the risk areas, which was inversely correlated with the levels of circulating CyPA detected in plasma samples from the same subjects. In testing whether Ivabradine may regulate the levels of CyPA, no changes in tissue CyPA were found in healthy pigs treated with 0.3 mg/kg Ivabradine, but interestingly, when analyzing the complex EMMPRIN/CyPA, rather high glycosylated EMMPRIN, which is required for EMMPRIN-mediated matrix metalloproteinase (MMP) activation and increased CyPA bonding to low-glycosylated forms of EMMPRIN were detected by day 7 after IR in pigs treated with Ivabradine. To study the mechanism by which Ivabradine may prevent secretion of CyPA, we first found that Ivabradine was time-dependent in inhibiting co-localization of CyPA with the granule exocytosis marker vesicle-associated membrane protein 1 (VAMP1). However, Ivabradine had no effect on mRNA expression nor in the proteasome and lysosome degradation of CyPA. In conclusion, our results point toward CyPA, its ligand EMMPRIN, and the complex CyPA/EMMPRIN as important targets of Ivabradine in cardiac protection against IR.

Hemodynamic effects of ivabradine use in combination with intravenous inotropic therapy in advanced heart failure

Intravenous inotropic therapy can be used in patients with advanced heart failure, as palliative therapy or as a bridge to cardiac transplantation or mechanical circulatory support, as well as in cardiogenic shock. Their use is limited to increasing cardiac output in low cardiac output states and reducing ventricular filling pressures to alleviate patient symptoms and improve functional class. Many advanced heart failure patients have sinus tachycardia as a compensatory mechanism to maintain cardiac output. However, excessive sinus tachycardia caused by intravenous inotropes can increase myocardial oxygen consumption, decrease coronary perfusion, and at extreme heart rates decrease ventricular filling and stroke volume. The limited available hemodynamic studies support the hypothesis that adding ivabradine, a rate control agent without negative inotropic effect, may blunt inotrope-induced tachycardia and its associated deleterious effects, while optimizing cardiac output by increasing stroke volume. This review analyzes the intriguing pathophysiology of combined intravenous inotropes and ivabradine to optimize the hemodynamic profile of patients in advanced heart failure. Graphical abstract Illustration of the beneficial and deleterious hemodynamic effects of intravenous inotropes in advanced heart failure, and the positive effects of adding ivabradine.

Ivabradine-Stimulated Microvesicle Release Induces Cardiac Protection against Acute Myocardial Infarction

Ivabradine can reduce heart rate through inhibition of the current I(f) by still unexplored mechanisms. In a porcine model of ischemia reperfusion (IR), we found that treatment with 0.3 mg/kg Ivabradine increased plasma release of microvesicles (MVs) over Placebo, as detected by flow cytometry of plasma isolated from pigs 7 days after IR, in which a tenfold increase of Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) containing (both high and low-glycosylated) MVs, was detected in response to Ivabradine. The source of MVs was investigated, finding a 37% decrease of CD31+ endothelial cell derived MVs, while CD41+ platelet MVs remained unchanged. By contrast, Ivabradine induced the release of HCN4+ (mostly cardiac) MVs. While no differences respect to EMMPRIN as a cargo component were found in endothelial and platelet derived MVs, Ivabradine induced a significant release of EMMPRIN+/HCN4+ MVs by day 7 after IR. To test the role of EMMPRIN+ cardiac MVs (EMCMV), H9c2 cell monolayers were incubated for 24 h with 10⁷ EMCMVs, reducing apoptosis, and increasing 2 times cell proliferation and 1.5 times cell migration. The in vivo contribution of Ivabradine-induced plasma MVs was also tested, in which 10⁸ MVs isolated from the plasma of pigs treated with Ivabradine or Placebo 7 days after IR, were injected in pigs under IR, finding a significant cardiac protection by increasing left ventricle ejection fraction and a significant reduction of the necrotic area. In conclusion ivabradine induces cardiac protection by increasing at least the release of EMMPRIN containing cardiac microvesicles.