Ivabradine and outcomes in chronic heart failure (SHIFT): a randomised placebo-controlled study

Advances in understanding and managing pediatric heart failure and transplant

PURPOSE OF REVIEW

This article highlights the most recent advances in a review of the current literature in the field of pediatric heart failure and transplantation.

RECENT FINDINGS

Diagnostically, the identification of new genetic factors has contributed to a deeper understanding of cardiomyopathy in children. Novel medications like sacubitril/valsartan and Sodium-Glucose cotransporter-2 (SGLT2) inhibitors, which are now standard in the adult population are being studied in pediatric population and offer new promise of pediatric heart failure treatment. Ventricular assist devices are more commonly used in cardiomyopathy patients and single ventricle patients as a bridge to transplant. Recent pediatric heart transplant society (PHTS) data demonstrated that waitlist survival improved significantly over the past decades (i) and new treatments such as daratumumab and eculizumab have been used in high-risk populations and demonstrate promising results. TEAMMATE trial is the first multicenter randomized clinical trial (RCT) in pediatric heart transplant (HT) to evaluate the safety and efficacy of everolimus (EVL) and low-dose tacrolimus (TAC) compared to standard-dose TAC and mycophenolate mofetil (MMF). It will provide valuable information about the safety and efficacy of EVL, TAC, and MMF (ii).Donor cell-free DNA has been used more in pediatric transplant recipients and has significantly decreased invasive EMB (iii).

SUMMARY

This past 5 years have witness dramatic progress in the field of pediatric heart failure and transplantation including more use of mechanical support in heart failure patients with various underlying etiology, especially use of mechanical support in single ventricle patients and the use of sacubitril/valsartan and SGLT2 inhibitors in the pediatric population. The problem of the highly sensitized transplant recipient remains, although novel therapeutics have been added to our toolbox of options to maintain healthy allograft function. Ongoing research aims to further enhance our understanding and management of pediatric heart failure, emphasizing the need for continued innovation in this complex field.

The Atrial Fibrillation and Heart Failure with Preserved Ejection Fraction "Twindemic" - Shared Root Causes and Treatment Targets

Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are comorbid conditions that are increasingly prevalent and have a high socioeconomic burden. This article discusses their shared pathophysiology, focusing on the triad of hypertension, obesity, and aging. We highlight the misperception that pharmacologic heart rate lowering is beneficial, which has resulted in an overprescription of beta-blockers in HFpEF and AF. In contrast, heart rate modulation through accelerated pacing provides hemodynamic and structural advantages, which have yielded significant improvements in quality of life, physical activity, and AF burden in the myPACE trial of patients with preclinical or overt HFpEF.

Ivabradine and Milrinone-Bridge to Recovery in New HFrEF With Low-Output Heart Failure

In patients with newly diagnosed heart failure with reduced ejection fraction (HFrEF) who are on a downward clinical trajectory, options are mostly limited to left ventricular assist device and transplantation. However, in those with factors favorable for reverse remodeling, every effort should be made to promote native myocardial recovery. We present three patients with newly diagnosed severe HFrEF, NYHA Class 3-4 symptoms, and low cardiac output with and without organ malperfusion. Ivabradine and/or home milrinone were used during their tenuous hemodynamic period as a bridge to optimize guideline-directed medical therapy (GDMT), device therapy, and eventual reverse remodeling. Evidence of structural heart improvement continued far beyond 1 year.

Ivabradine Approved and Other Uses in Clinical Practice: A Systematic Review

ABSTRACT

Heart rate (HR) stands as a prognostic indicator of cardiovascular disease and a modifiable risk factor in heart failure (HF). Medication intolerance can curtail the application of conventional HR-lowering β-blockers to the optimum target dose. Ivabradine (IVA), a specific negative-chronotropic agent, selectively inhibits I f current in pacemaker cells of the sinoatrial node without depressing myocardial contractility or comprising hemodynamics. This review summarized ivabradine's clinical labeled and off-label uses and mechanism of action focusing on the clinical outcomes. PubMed was searched up to January 2024 using the main keywords of IVA, coronary artery disease (CAD), HF, postural tachycardia syndrome (POTS), and tachyarrhythmia. To comprehensively review IVA's clinical indications, mechanisms, and therapeutic effects, all studies investigating treatment with IVA in humans were included, comprising different types of studies such as randomized controlled trials and longitudinal prospective observational studies. After screening, 141 studies were included in our review. A large number of reviewed articles were allocated to heart failure with reduced ejection fraction and CAD, suggesting IVA as an alternative to β-blockers in case of contraindications or intolerance. The beneficial effects of IVA as premedication for coronary computed tomography angiography, HR lowering in POTS, and inappropriate sinus tachycardia constituted most studies among off-label uses. The promising results have been reported on the efficacy of IVA in controlling HR, especially in patients with inappropriate sinus tachycardia or POTS. Owing to the unique mechanism of action, IVA has the potential to be used more frequently in future clinical practice.

Beyond quadruple therapy: the potential roles for ivabradine, vericiguat, and omecamtiv mecarbil in the therapeutic armamentarium

Quadruple therapy is effective for patients with heart failure with reduced ejection fraction, providing significant clinical benefits, including reduced mortality. Clinicians are now in an era focused on how to initiate and titrate quadrable therapy in the early phase of the disease trajectory, including during heart failure hospitalization. However, patients with heart failure with reduced ejection fraction still face a significant "residual risk" of mortality and heart failure hospitalization. Despite the effective implementation of quadruple therapy, high mortality and rehospitalization rates persist in heart failure with reduced ejection fraction, and many patients cannot maximize therapy due to side effects such as hypotension and renal dysfunction. In this context, ivabradine, vericiguat, and omecamtiv mecarbil may have adjunct roles in addition to quadruple therapy (note that omecamtiv mecarbil is not currently approved for clinical use). However, the contemporary use of ivabradine and vericiguat is relatively low globally, likely due in part to the under-recognition of the role of these therapies as well as costs. This review offers clinicians a straightforward guide for bedside evaluation of potential candidates for these medications. Quadruple therapy, with strong evidence to reduce mortality, should always be prioritized for implementation. As second-line therapies, ivabradine could be considered for patients who cannot achieve optimal heart rate control (≥ 70 bpm at rest) despite maximally tolerated beta-blocker dosing. Vericiguat could be considered for high-risk patients who have recently experienced worsening heart failure events despite being on quadrable therapy, but they should not have N-terminal pro-B-type natriuretic peptide levels exceeding 8000 pg/mL. In the future, omecamtiv mecarbil may be considered for severe heart failure (New York Heart Association class III to IV, ejection fraction ≤ 30%, and heart failure hospitalization within 6 months) when current quadrable therapy is limited, although this is still hypothesis-generating and requires further investigation before its approval.

Physiological effects of ivabradine in heart failure and beyond

Ivabradine is a pharmacologic agent that inhibits the funny current responsible for determining heart rate in the sinoatrial node. Ivabradine's clinical potential has been investigated in the context of heart failure since it is associated with reduced myocardial oxygen demand, enhanced diastolic filling, stroke volume, and coronary perfusion time; however, it is yet to demonstrate definitive mortality benefit. Alternative effects of ivabradine include modulation of the renin-angiotensin-aldosterone system, sympathetic activation, and endothelial function. Here, we review key clinical trials informing the clinical use of ivabradine and explore opportunities for leveraging its potential pleiotropic effects in other diseases, including treatment of hyperadrenergic states and mitigating complications of COVID-19 infection.

Management of patients with heart failure and chronic kidney disease

Chronic kidney disease (CKD) and heart failure are often co-existing conditions due to a shared pathophysiological process involving neurohormonal activation and hemodynamic maladaptation. A wide range of pharmaceutical and interventional tools are available to patients with CKD, consisting of traditional ones with decades of experience and newer emerging therapies that are rapidly reshaping the landscape of medical care for this population. Management of patients with heart failure and CKD requires a stepwise approach based on renal function and the clinical phenotype of heart failure. This is often challenging due to altered drug pharmacokinetics interactions with various degrees of kidney function and frequent adverse effects from the therapy that lead to poor patient tolerance. Despite a great body of clinical evidence and guidelines that have offered various treatment options for patients with heart failure and CKD, respectively, patients with CKD are still underrepresented in heart failure clinical trials, especially for those with advanced CKD and end-stage renal disease (ESRD). Future studies are needed to better understand the generalizability of these therapeutic options among heart failures with different stages of CKD.

Novel Therapies for the Treatment of Cardiovascular Disease

Over the last decade, randomized clinical trials of several pharmacologic agents have demonstrated a reduction in cardiovascular mortality and other important secondary outcomes. Angiotensin-Neprilysin Inhibitors and Sodium-Glucose Co-transporter 2 inhibitors have now become pillars in the treatment of heart failure. Ivabradine is a negative chronotropic agent used as an adjunctive therapy in patients with heart failure. Two new hypertension therapies, zilebresiran and aprocitentan, are currently in investigational stages. Finally, mavacamten has emerged as a pharmacologic treatment for hypertrophic obstructive cardiomyopathy. Practitioners must be familiar with the indications and side effects of newer therapies as they are now frequently prescribed.

Exploring the Association Between Heart Rate Control and Rehospitalization: A Real-World Analysis of Patients Hospitalized with Heart Failure with Reduced Ejection Fraction

BACKGROUND

In patients with heart failure with reduced ejection fraction (HFrEF), lower discharge heart rate (HR) is known to be associated with better outcomes. However, the effect of HR control on patient outcomes, and the demographic and clinical determinants of this association, are not well documented.

OBJECTIVES

The purpose of this work was to evaluate the association between the HR control and the risk of post-discharge rehospitalization in patients hospitalized with HFrEF.

METHODS

Data were collected using a retrospective medical record review in the USA. Reduction in HR between admission and discharge ("HR control") defined the primary exposure, categorized as no reduction, > 0 to < 20% reduction, and ≥ 20% reduction. Time to first rehospitalization in the post-discharge follow-up defined the study outcome and was analyzed using multivariable Cox regression modeling.

RESULTS

A total of 1002 patients were analyzed (median age, 63 years; median follow-up duration, 24.2 months). At admission, 59.1% received beta-blockers, 57.4% received diuretics, and 47.5% received angiotensin-converting enzyme (ACE) inhibitors. Most patients (90.5%) achieved some HR control (38.4% achieved > 0 to < 20% reduction, and 52% achieved ≥ 20% reduction). Approximately 39% were rehospitalized during the follow-up (14% within 30 days). In multivariable analysis, patients with > 0 to < 20% reduction in HR had a 39% lower risk of rehospitalization [hazard ratio 0.61; 95% confidence interval (CI) 0.43-0.85]; patients with ≥ 20% reduction in HR had a 38% lower rehospitalization risk (hazard ratio 0.62; 95% CI 0.45-0.87) than those with no HR reduction.

CONCLUSIONS

Reduction in HR between admission and discharge was associated with reduced risk for rehospitalization. Findings indicate HR control as an important goal in the management of patients hospitalized for HFrEF.

Atrial Fibrillation and Heart Failure With Reduced Ejection Fraction: New Assessment of an Old Problem

Atrial fibrillation (AF) and heart failure (HF)-specifically, heart failure with reduced ejection fraction (HFrEF)-often coexist, and each contributes to the propagation of the other. This relationship extends from the mechanistic and physiological to clinical syndromes, quality of life, and long-term cardiovascular outcomes. The risk factors for AF and HF overlap and create a critical opportunity to prevent adverse outcomes among patients at greatest risk for either condition. Increasing recognition of the linkages between AF and HF have led to widespread interest in designing diagnostic, predictive, and interventional strategies targeting all aspects of disease, from identifying genetic predisposition to addressing social determinants of health. Advances across this spectrum culminated in updated multisociety guidelines for management of AF, which includes specific consideration of comorbid AF and HF. This review expands on these guidelines by further highlighting relevant clinical trial findings and providing additional context for the evolving recommendations for management in this important and growing population.

From Hospital to Home: Evidence-Based Care for Worsening Heart Failure

Heart failure (HF) is a leading cause of hospitalization in older adults. Patients are at high risk of readmission and death following hospitalization for HF. There is no standard approach of health care delivery during the hospital-to-home transition period, leaving missed opportunities in care optimization. In this review, we discuss contemporary randomized clinical trials that tested decongestion strategies, disease-modifying therapies, and health care services that inform the care of patients with worsening HF. We provide evidence-informed recommendations for optimizing therapies and improving outcomes during and following hospitalization for HF. These include adequate decongestion with loop diuretics and select sequential nephron blockade strategies based on early evaluation of diuretic response; initiation of disease-modifying pharmacotherapies prior to hospital discharge with close follow-up and optimization after discharge; cardiac rehabilitation; and transitional or palliative care referral post-hospitalization. Evidence-based implementation strategies to facilitate broad uptake include digital health tools and algorithm-driven optimization of pharmacotherapies.

Recovery From Left Ventricular Dysfunction

The treatment of heart failure is an evolving field of cardiology, with increasingly available therapeutics and significant disease burden. With the effective treatments available, we see a substantial patient population whose once reduced ejection fraction (EF) has normalized. Studies have assessed the natural history of these patients with improved EF and found improved mortality as compared with those patients with persistently reduced EF, with some evidence stating that each 5% increase in left ventricular EF correlates with a 4.9-fold decrease in the odds of mortality. This prognostic divergence has led to the recognition of this subset of patients as having a unique heart failure diagnosis, distinct from heart failure with reduced EF (HFrEF) or heart failure with preserved EF and to the adoption of the term heart failure with recovered EF. These patients, despite having improved mortality, do retain some of the molecular and histologic changes seen in HFrEF and are still at risk for decline in left ventricular function and adverse cardiac events, particularly when medical therapy is stopped. This distinction between recovery of EF and true myocardial recovery led to recent guidelines recommending continuation of guideline-directed medical therapy indefinitely, as well as surveillance echocardiography.

How to Optimize Goal-Directed Medical Therapy (GDMT) in Patients with Heart Failure

PURPOSE OF REVIEW

Heart failure is a clinical syndrome with signs and symptoms from underlying cardiac abnormality and evidence of pulmonary or systemic congestion on laboratory testing or other objective findings (Bozkurt et al. in Eur J Heart Fail 23:352-380, 2021). Heart failure with reduced ejection fraction (HFrEF), when heart failure is due to underlying reduction in ejection fraction to ≤ 40. The goal of this review is to briefly describe the mechanisms and benefits of the various pharmacological interventions described in the 2022 AHA/ACC/HFSA Guidelines focusing on Stage C: Symptomatic Heart Failure HFrEF, while providing basic guidance on safe use of these medications.

RECENT FINDINGS

Use of medications from each class as recommended in the 2022 Guidelines can provide significant morbidity and mortality benefits for our patients. Despite advances in therapeutics for patients with HFrEF, patients are frequently under treated and more research is needed to help optimize management of these complicated patients.

Why Have We Not Been Able to Demonstrate Reduced Mortality in Patients With HFmrEF/HFpEF?

No randomized controlled trial has yet demonstrated a statistically significant reduction in mortality in patients with heart failure and mildly reduced ejection (HFmrEF) or heart failure and preserved ejection fraction (HFpEF), in contrast to the benefits observed in heart failure with reduced ejection fraction (HFrEF). However, this probably reflects the statistical power of trials to date to show an effect on mortality rather than mechanistic differences between HFmEF/HFpEF and HFrEF or differences in treatment efficacy. Compared to patients with HFrEF, those with HFmrEF/HFpEF have lower mortality rates and a smaller proportion of potentially modifiable cardiovascular deaths (as opposed to unmodifiable noncardiovascular deaths). In addition, some causes of cardiovascular deaths may not be reduced by treatments for HF. Therefore, the low rate of potentially modifiable deaths in patients with HFmrEF/HFpEF, compared with HFrEF, has made it challenging to demonstrate a reduction in death (or cardiovascular death) in trials to date.

The Current State of Realistic Heart Models for Disease Modelling and Cardiotoxicity

One of the many unresolved obstacles in the field of cardiovascular research is an uncompromising in vitro cardiac model. While primary cell sources from animal models offer both advantages and disadvantages, efforts over the past half-century have aimed to reduce their use. Additionally, obtaining a sufficient quantity of human primary cardiomyocytes faces ethical and legal challenges. As the practically unlimited source of human cardiomyocytes from induced pluripotent stem cells (hiPSC-CM) is now mostly resolved, there are great efforts to improve their quality and applicability by overcoming their intrinsic limitations. The greatest bottleneck in the field is the in vitro ageing of hiPSC-CMs to reach a maturity status that closely resembles that of the adult heart, thereby allowing for more appropriate drug developmental procedures as there is a clear correlation between ageing and developing cardiovascular diseases. Here, we review the current state-of-the-art techniques in the most realistic heart models used in disease modelling and toxicity evaluations from hiPSC-CM maturation through heart-on-a-chip platforms and in silico models to the in vitro models of certain cardiovascular diseases.

Optimizing Management of Stable Angina: A Patient-Centered Approach Integrating Revascularization, Medical Therapy, and Lifestyle Interventions

Angina pectoris may arise from obstructive coronary artery disease (CAD) or in the absence of significant CAD (ischemia with nonobstructed coronary arteries [INOCA]). Therapeutic strategies for patients with angina and obstructive CAD focus on reducing cardiovascular events and relieving symptoms, whereas in INOCA the focus shifts toward managing functional alterations of the coronary circulation. In obstructive CAD, coronary revascularization might improve angina status, although a significant percentage of patients present angina persistence or recurrence, suggesting the presence of functional mechanisms along with epicardial CAD. In patients with INOCA, performing a precise endotype diagnosis is crucial to allow a tailored therapy targeted toward the specific pathogenic mechanism. In this expert opinion paper, we review the evidence for the management of angina, highlighting the complementary role of coronary revascularization, optimal medical therapy, and lifestyle interventions and underscoring the importance of a personalized approach that targets the underlying pathobiology.

Comparative Analysis of ECG and Holter Monitoring in the Assessment of Heart Rate in Heart Failure with Reduced Ejection Fraction and Sinus Rhythm

BACKGROUND

Heart rate (HR) has shown prognostic value in patients with heart failure with reduced ejection fraction (HFrEF) and sinus rhythm. However, the method of measurement is debated in the literature.

OBJECTIVES

To compare HR on Holter with 3 resting electrocardiograms (ECG1, ECG2, and ECG3) in patients with HFrEF and sinus rhythm.

METHODS

This was a cross-sectional study with 135 patients with heart failure with ejection fraction ≤ 40% and sinus rhythm. HR was assessed by ECG and Holter. Analyses included intraclass correlation coefficient (ICC), robust regression, root mean squared error, Bland-Altman, and area under the receiver operating characteristic (ROC) curve. A significance level of 0.05 and Bonferroni-Holm adjustment were adopted to minimize type I errors.

RESULTS

The median [interquartile range] age and ejection fraction were 65 years [16] and 30% [11], respectively. The ICC of the 3 ECGs was 0.922 (95% confidence interval: 0.892; 0.942). The robust regression coefficients for ECG1 and ECG3 were 0.20 (95% confidence interval: 0.12; 0.29) and 0.21 (95% confidence interval: 0.06; 0.36). The robust R2 was 0.711 (95% confidence interval: 0.628; 0.76). In the Bland-Altman agreement analysis, the limits of agreement were -17.0 (95% confidence interval: -19.0; -15.0) and 32.0 (95% confidence interval: 30.0; 34.0). The area under the ROC curve was 0.896 (95% confidence interval: 0.865; 0.923).

CONCLUSION

The HR on ECG showed high agreement with the HR on Holter, validating its clinical use in patients with HFrEF and sinus rhythm. However, agreement was suboptimal in one third of patients with HR below 70 bpm on ECG; thus, 24-hour Holter monitoring should be considered in this context.

How adoption of new pharmaceuticals can impact US health system reimbursement under alternative payment models: An economic model measuring the impact of sotagliflozin among patients with heart failure and diabetes

BACKGROUND

Heart failure (HF) is among the leading causes of death in the United States. Further, patients hospitalized because of HF with comorbid diabetes mellitus (DM) are at a significantly increased risk of death and rehospitalization. Results from the SOLOIST-WHF trial show that sotagliflozin lowered rates of readmission among hospitalized patients with HF and comorbid DM. However, it is unclear what the economic impact of the use of sotagliflozin would be on hospitals and health systems, particularly in an age where provider reimbursement is increasingly tied to value.

OBJECTIVE

To quantify the 1-year financial impact on US provider health systems of adopting sotagliflozin relative to standard of care (SoC) across different alternative payment models.

METHODS

This study created a 3-part decision tree model to quantify the financial impact of using sotagliflozin to treat patients hospitalized with HF in a US hospital setting. The model first estimated the clinical and economic outcomes of health systems with current SoC (no sotagliflozin) to treat US patients hospitalized for HF with comorbid DM. Then, using the results from the SOLOIST trial, the changes in clinical and economic outcomes with sotagliflozin adoption were modeled. Finally, the differences in health care utilization between sotagliflozin and SoC arms were translated to differences in health system reimbursement in the context of 3 common alternative payment models (APMs) in addition to the baseline fee-for-service (FFS) model: FFS with the Hospital Readmissions Reduction Program, the Bundled Payments for Care Improvement-Advanced program, and Accountable Care Organizations.

RESULTS

A typical community hospital would have 83.4 patients per year on average with an index HF hospitalization with comorbid DM. The model predicted that sotagliflozin would reduce the probability of hospitalization, emergency department visits, and deaths by 29.3%, 38.5%, and 17.8%, respectively, compared with SoC. For hospitals not participating in APM programs, sotagliflozin resulted in a net loss of $92.94 per person ($7,754 per health system). Conversely, when accounting for provider health system participation in APMs, sotagliflozin adoption increased financial returns by $4,720 per person ($305,604 per health system) under the Hospital Readmissions Reduction Program, $1,200 per person ($100,106 per health system) for the Bundled Payments for Care Improvement-Advanced program, and $1,078 per person ($31,029 per health system) for Accountable Care Organizations. Based on the national average composition of APM reimbursement, sotagliflozin adoption resulted in a $1,576 increase in margin per patient with HF ($105,454 per health system).

CONCLUSIONS

Although sotagliflozin adoption reduced health system revenue in an FFS payment model, it led to a net positive financial impact after accounting for APM bonus payments.

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.

Comparison of the stage-dependent mitochondrial changes in response to pressure overload between the diseased right and left ventricle in the rat

The right ventricle (RV) differs developmentally, anatomically and functionally from the left ventricle (LV). Therefore, characteristics of LV adaptation to chronic pressure overload cannot easily be extrapolated to the RV. Mitochondrial abnormalities are considered a crucial contributor in heart failure (HF), but have never been compared directly between RV and LV tissues and cardiomyocytes. To identify ventricle-specific mitochondrial molecular and functional signatures, we established rat models with two slowly developing disease stages (compensated and decompensated) in response to pulmonary artery banding (PAB) or ascending aortic banding (AOB). Genome-wide transcriptomic and proteomic analyses were used to identify differentially expressed mitochondrial genes and proteins and were accompanied by a detailed characterization of mitochondrial function and morphology. Two clearly distinguishable disease stages, which culminated in a comparable systolic impairment of the respective ventricle, were observed. Mitochondrial respiration was similarly impaired at the decompensated stage, while respiratory chain activity or mitochondrial biogenesis were more severely deteriorated in the failing LV. Bioinformatics analyses of the RNA-seq. and proteomic data sets identified specifically deregulated mitochondrial components and pathways. Although the top regulated mitochondrial genes and proteins differed between the RV and LV, the overall changes in tissue and cardiomyocyte gene expression were highly similar. In conclusion, mitochondrial dysfuntion contributes to disease progression in right and left heart failure. Ventricle-specific differences in mitochondrial gene and protein expression are mostly related to the extent of observed changes, suggesting that despite developmental, anatomical and functional differences mitochondrial adaptations to chronic pressure overload are comparable in both ventricles.

Prognostically Optimal Heart Rate at Discharge in Hospitalized Patients With Heart Failure and Atrial Fibrillation

Background

Managing heart rate (HR) is crucial for enhancing clinical prognosis in patients with heart failure (HF) and atrial fibrillation (AF). Nevertheless, the prognostic impact of HR at discharge in hospitalized HF patients remains unclear.

Objectives

This study aimed to determine the HR associated with the lowest risk of death and HF in patients hospitalized with HF and AF.

Methods

In this observational study, 334 persistent AF patients were analyzed from a database of 1,930 consecutive HF hospitalizations. Exclusion criteria included sinus rhythm or paroxysmal AF, cardiac pacemakers, or unrecorded HR at discharge. Participants were divided into four groups based on HR at discharge in 10 beats/min increments. The primary endpoint was a composite of death from any cause and rehospitalization due to HF. The association between resting HR and the primary endpoint was determined using Kaplan-Meier analysis and Cox proportional hazards models.

Results

The median follow-up period was 389 days, with 133 patients (39.8%) reaching the primary endpoint. Kaplan-Meier analysis revealed a significantly higher primary endpoint incidence in patients with HR >81 beats/min at discharge compared to those with HR <60 beats/min (log-rank test for trend: P = 0.039). Multivariable Cox regression analysis showed that HR >81 beats/min at discharge was associated with the primary endpoint, with a hazard ratio of 1.79 (95% CI: 1.04-3.07), compared to HR <60 beats/min.

Conclusions

The findings suggest that controlling HR to less than 80 beats/min at discharge may lead to better clinical outcomes in patients with HF and persistent AF.

Elevated resting heart rate is associated with mortality in patients with chronic kidney disease

A higher heart rate is recognized as an independent risk factor for all-cause mortality and cardiovascular events in the general population. However, the association between elevated heart rate and clinical adverse outcomes in patients with non-dialysis-dependent chronic kidney disease (CKD) has not been sufficiently investigated. A total of 1353 participants enrolled in the Fukushima CKD Cohort Study were examined to investigate associations between resting heart rate and clinical adverse outcomes using Cox proportional hazards analysis. The primary outcome of the present study was all-cause mortality, with cardiovascular events as the secondary outcome. Participants were stratified into four groups based on resting heart rate levels at baseline (heart rate < 70/min, ≥ 70 and < 80/min, ≥ 80 and < 90/min, and ≥ 90/min). During the median observation period of 4.9 years, 123 participants died, and 163 cardiovascular events occurred. Compared with the reference level heart rate < 70/min group, the adjusted hazard ratios (HRs) for all-cause mortality were 1.74 (1.05-2.89) and 2.61 (1.59-4.29) for the heart rate ≥ 80 and < 90/min group and heart rate ≥ 90/min group, respectively. A significantly higher risk of cardiovascular events was observed in the heart rate ≥ 80/min and < 90/min group (adjusted HR 1.70, 1.10-2.62), but not in the heart rate ≥ 90/min group (adjusted HR 1.45, 0.90-2.34). In patients with non-dialysis-dependent CKD, a higher resting heart rate was associated with increased all-cause mortality.

Impact of optimized transcutaneous auricular vagus nerve stimulation on cardiac autonomic profile in healthy subjects and heart failure patients

Objective.To determine the optimal frequency and site of stimulation for transcutaneous vagus nerve stimulation (tVNS) to induce acute changes in the autonomic profile (heart rate (HR), heart rate variability (HRV)) in healthy subjects (HS) and patients with heart failure (HF).Approach.We designed three single-blind, randomized, cross-over studies: (1) to compare the acute effect of left tVNS at 25 Hz and 10 Hz (n= 29, age 60 ± 7 years), (2) to compare the acute effect of left and right tVNS at the best frequency identified in study 1 (n= 28 age 61 ± 7 years), and (3) to compare the acute effect of the identified optimal stimulation protocol with sham stimulation in HS and HF patients (n= 30, age 59 ± 5 years, andn= 32, age 63 ± 7 years, respectively).Main results.In study 1, left tragus stimulation at 25 Hz was more effective than stimulation at 10 Hz in decreasing HR (-1.0 ± 1.2 bpm,p< 0.001 and -0.5 ± 1.6 bpm, respectively) and inducing vagal effects (significant increase in RMSSD, and HF power). In study 2, the HR reduction was greater with left than right tragus stimulation (-0.9 ± 1.5 bpm,p< 0.01 and -0.3 ± 1.4 bpm, respectively). In study 3 in HS, left tVNS at 25 Hz significantly reduced HR, whereas sham stimulation did not (-1.1 ± 1.2 bpm,p< 0.01 and -0.2 ± 2.9 bpm, respectively). In HF patients, both active and sham stimulation produced negligible effects.Significance.Left tVNS at 25 Hz is effective in acute modulation of cardiovascular autonomic control (HR, HRV) in HS but not in HF patients (NCT05789147).

[Research progress in the application of ivabradine in children with cardiovascular diseases]

Ivabradine, as a specific If current inhibitor, has been widely used in the treatment of chronic heart failure in adults due to its ability to reduce heart rate without affecting myocardial contractility and blood pressure. It has also shown good effects in various types of tachyarrhythmias. However, the application of ivabradine in pediatric cardiovascular diseases still faces many limitations. This article reviews the current research progress on the use of ivabradine in treating pediatric cardiovascular diseases both domestically and internationally, aiming to provide guidance for pediatric cardiologists. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 782-788.

Evaluation and Management of Chronic Heart Failure in Children and Adolescents With Congenital Heart Disease: A Scientific Statement From the American Heart Association

With continued medical and surgical advancements, most children and adolescents with congenital heart disease are expected to survive to adulthood. Chronic heart failure is increasingly being recognized as a major contributor to ongoing morbidity and mortality in this population as it ages, and treatment strategies to prevent and treat heart failure in the pediatric population are needed. In addition to primary myocardial dysfunction, anatomical and pathophysiological abnormalities specific to various congenital heart disease lesions contribute to the development of heart failure and affect potential strategies commonly used to treat adult patients with heart failure. This scientific statement highlights the significant knowledge gaps in understanding the epidemiology, pathophysiology, staging, and outcomes of chronic heart failure in children and adolescents with congenital heart disease not amenable to catheter-based or surgical interventions. Efforts to harmonize the definitions, staging, follow-up, and approach to heart failure in children with congenital heart disease are critical to enable the conduct of rigorous scientific studies to advance our understanding of the actual burden of heart failure in this population and to allow the development of evidence-based heart failure therapies that can improve outcomes for this high-risk cohort.

Prognostic Value of Coronary Microvascular Dysfunction Assessed by Coronary Angiography-Derived Index of Microcirculatory Resistance in Patients With ST-Segment Elevation Myocardial Infarction

BACKGROUND

CaIMR is proposed as a novel angiographic index designed to assess microcirculation without the need for pressure wires or hyperemic agents. We aimed to investigate the impact of caIMR on predicting clinical outcomes in STEMI patients.

METHODS

One hundred and forty patients with STEMI who received PCI in Putuo Hospital of Shanghai from October 2021 to September 2022 were categorized into CMD and non-CMD groups according to the caIMR value. The baseline information, patient-related examinations, and the occurrence of MACE at the 12-month follow-up were collected to investigate risk factors in patients with STEMI.

RESULTS

We divided 140 patients with STEMI enrolled into two groups according to caIMR results, including 61 patients diagnosed with CMD and 79 patients diagnosed with non-CMD. A total of 21 MACE occurred during the 1 year of follow-up. Compared with non-CMD group, patients with CMD showed a significantly higher risk of MACE. A multivariate Cox regression model was conducted for the patients, and it was found thatcaIMR was a significant predictor of prognosis in STEMI patients (HR: 8.921). Patients with CMD were divided into culprit vascular CMD and non-culprit vascular CMD, and the result found that culprit vascular CMD was associated with the incidence of MACE (OR: 4.75) and heart failure (OR: 7.50).

CONCLUSION

CaIMR is a strong predictor of clinical outcomes and can provide an objective risk stratification for patients with STEMI. There is a strong correlation among leukocyte index, the use of furosemide, Killips classification, and clinical outcomes.

A Systematic Review and Meta-Analysis of Randomised Controlled Trials Assessing Clinical and Haemodynamic Outcomes of Ivabradine in Heart Failure With Reduced Ejection Fraction Patients

BACKGROUND

Ivabradine, a pure bradycardic agent, can be given to heart failure reduced ejection fraction (HFrEF) patients with a sinus rhythm of ≥70 bpm on a maximum beta blocker dose, or when beta blockers are contraindicated. This study aimed to see how ivabradine affects the clinical and haemodynamic outcomes of HFrEF patients.

METHODS

This systematic review and meta-analysis searched ClinicalTrials.gov, OpenMD, ProQuest, PubMed, and ScienceDirect for potential articles. All relevant data were extracted. For all pooled effects, the random effect model was applied.

RESULTS

A total of 18,972 heart failure (HF) patients from nine randomised clinical trials (RCTs) were involved in this study. Ivabradine decreased the risk of HF mortality (RR 0.79; 95% CI 0.64-0.98; p=0.03) and HF hospitalisation (RR 0.80; 95% CI 0.65-0.97; p=0.03). Ivabradine was related to a greater reduction in heart rate (MD -12.21; 95% CI -15.47 - -8.96; p<0.01) and left ventricular ejection fraction (LVEF) improvement (MD 3.24; 95% CI 2.17-4.31; p <0.01) compared with placebo. Asymptomatic bradycardia (RR 4.25; 95% CI 3.36-5.39; p<0.01) and symptomatic bradycardia (RR 3.99; 95% CI 3.17-5.03; p<0.01) were higher in the ivabradine group.

CONCLUSION

Ivabradine can reduce the risk of HF mortality and HF hospitalisation in HFrEF patients. Ivabradine also effectively reduces resting heart rate and improves LVEF. However, ivabradine is associated with a greater risk of symptomatic and asymptomatic bradycardia.

Sex-related similarities and differences in responses to heart failure therapies

Although sex-related differences in the epidemiology, risk factors, clinical characteristics and outcomes of heart failure are well known, investigations in the past decade have shed light on an often overlooked aspect of heart failure: the influence of sex on treatment response. Sex-related differences in anatomy, physiology, pharmacokinetics, pharmacodynamics and psychosocial factors might influence the response to pharmacological agents, device therapy and cardiac rehabilitation in patients with heart failure. In this Review, we discuss the similarities between men and women in their response to heart failure therapies, as well as the sex-related differences in treatment benefits, dose-response relationships, and tolerability and safety of guideline-directed medical therapy, device therapy and cardiac rehabilitation. We provide insights into the unique challenges faced by men and women with heart failure, highlight potential avenues for tailored therapeutic approaches and call for sex-specific evaluation of treatment efficacy and safety in future research.

Budget impact analyses for treatment of heart failure. A systematic review

Heart failure (HF) is increasing globally and turning out to be a serious worldwide public health problem with significant morbidity and mortality. This study aims to systemically review the budget impact analysis of heart failure treatments on health care expenditure worldwide. Scientific databases such as PubMed, Web of Science, Scopus, and Google Scholar were searched for budget impact analysis and heart failure treatments, over January 2001 to August 2023. The quality assessment of the selected studies was evaluated through ISPOR practice guideline. Nineteen studies were included in this systematic review. Based on ISPOR recommendations, most studies were performed on a 1-year time horizon and used a government (public health) or health system perspective. Data for selected studies was mainly collected from randomized clinical trials, published literature, pharmaceutical companies, and registry data. Only direct costs were reported in the studies. Sensitivity analyses were stated in almost all studies. However, studies conducted in high-income countries reported sensitivity analyses more elaborately than those performed in low- and middle-income countries. In many published articles related to the budget impact analyses of heart failure treatment, addition of new treatments to the health system's formularies can lead to a reduction in cardiovascular hospitalization rates, re-hospitalization rates, cardiac-associated mortality rates, and an improvement in heart failure class, which can decrease the costs of hospitalizations, specified care visits, primary care visits, and other related treatments.

GLP-1 increases heart rate by a direct action on the sinus node

AIMS

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly used to treat type 2 diabetes and obesity. Albeit cardiovascular outcomes generally improve, treatment with GLP-1 RAs is associated with increased heart rate, the mechanism of which is unclear.

METHODS AND RESULTS

We employed a large animal model, the female landrace pig, and used multiple in-vivo and ex-vivo approaches including pharmacological challenges, electrophysiology and high-resolution mass spectrometry to explore how GLP-1 elicits an increase in heart rate. In anaesthetized pigs, neither cervical vagotomy, adrenergic blockers (alpha, beta or combined alpha-beta blockade), ganglionic blockade (hexamethonium) nor inhibition of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels (ivabradine) abolished the marked chronotropic effect of GLP-1. GLP-1 administration to isolated perfused pig hearts also increased heart rate, which was abolished by GLP-1 receptor blockade. Electrophysiological characterization of GLP-1 effects in vivo and in isolated perfused hearts localized electrical modulation to the atria and conduction system. In isolated sinus nodes, GLP-1 administration shortened action potential cycle length of pacemaker cells and shifted the site of earliest activation. The effect was independent of HCN blockade. Collectively, these data support a direct effect of GLP-1 on GLP-1 receptors within the heart. Consistently, single nucleus RNA sequencing (snRNAseq) showed GLP-1 receptor expression in porcine pacemaker cells. Quantitative phosphoproteomics analyses of sinus node samples revealed that GLP-1 administration leads to phosphorylation changes of calcium cycling proteins of the sarcoplasmic reticulum, known to regulate heart rate.

CONCLUSION

GLP-1 has direct chronotropic effects on the heart mediated by GLP-1 receptors in pacemaker cells of the sinus node, inducing changes in action potential morphology and the leading pacemaker site through a calcium signaling response characterized by PKA-dependent phosphorylation of Ca2+ cycling proteins involved in pace making. Targeting the pacemaker calcium clock may be a strategy to lower heart rate in GLP-1 RA recipients.

The efficacy and safety of ivabradine hydrochloride in hemodialysis patients with chronic heart failure

INTRODUCTION

There is little evidence for ivabradine hydrochloride in patients undergoing hemodialysis.

METHODS

In this open-label prospective interventional trial of hemodialysis patients with chronic heart failure, during 12 weeks of treatment, changes in Heart rate (HR), frequency of dialysis-related hypotension were examined, and we investigated health-related quality of life (HR-QOL) and adverse effects.

RESULTS

18 patients from 6 facilities were enrolled in the study. HR significantly decreased over time, from 87 ± 12.61/min at baseline to 75.85 ± 8.91/min (p = 0.0003), and systolic blood pressure also increased significantly (p < 0.0001). The frequency of dialysis-related hypotension was markedly reduced (p = 0.0001). The HR-QOL survey showed significant improvements in Social Functioning among others (p = 0.0178). No specific adverse events occurred.

CONCLUSION

Ivabradine hydrochloride improved dialysis-related hypotension. Furthermore, the HR-QOL improvement effect were suggested. These results demonstrated the safety and effectiveness of ivabradine hydrochloride.

Safety of cardiovascular disease drugs approved between 2014 and 2021 in the US: a pharmacovigilance analysis

BACKGROUND

Recently FDA-approved drugs for cardiovascular disease (CVD) require robust post-marketing surveillance. The objective of this study was to assess their safety using a large pharmacovigilance database.

RESEARCH DESIGN AND METHODS

We analyzed adverse event (AE) reports for 17 drugs approved from 2014 to 2021, utilizing the FDA Adverse Event Reporting System (FAERS). Descriptive and disproportionality analyses were conducted by estimating the reporting odds ratio (ROR) and its 95% confidence interval.

RESULTS

Among the 43,664,773 AE reports 97,702 (0.22%) were related to newly approved CVD drugs. No AEs were reported for finerenone and evinacumab. The results from the disproportionality analyses revealed potential risks of acute kidney injury (ROR = 8.24, 95% CI: 6.05-11.22), cardiac failure (ROR = 4.80, 95% CI: 3.82-6.05), and hypotension (ROR = 3.98, 95% CI: 3.44-4.61) among sacubitril/valsartan users. Additionally, ivabradine was found to be associated with tachycardia (ROR = 11.94, 95% CI: 8.35-17.08), abnormal feeling (ROR = 4.40, 95% CI: 2.70-7.18), and dizziness (ROR = 2.56, 95% CI: 1.68-3.90).

CONCLUSIONS

This study identified specific safety concerns related to recently approved CVD drugs. Further research is required to understand the underlying mechanisms and clinical implications of these findings.

Novel Use of Ivabradine for Persistent Sinus Tachycardia in a Patient on Extracorporeal Life Support With Right Ventricular Dysfunction

Persistent sinus tachycardia (pST) has been associated with adverse cardiovascular events in critically ill patients. Pharmacological control of heart rate with negative inotropic agents has proven to be safe but could be potentially dangerous in patients with concomitant right ventricular (RV) dysfunction. Ivabradine, a medication devoid of negative inotropy, could be a potentially safe solution for this patient population when adequate heart rate control is desired. A 17-year-old male with a history of vaping developed acute respiratory distress syndrome (ARDS) and RV dysfunction, requiring extra corporal life support (ECLS). He suffered from pST. Given his RV dysfunction, a beta-blocker was avoided, and ivabradine was used safely with improvement of his pST. This case demonstrates the efficacy of ivabradine to reduce heart rate and avoid the use of beta-blockers for patients with RV dysfunction, which could be detrimental. Ivabradine was shown to lower the heart rate without altering hemodynamic parameters.

Challenging and target-based shifting strategies for heart failure treatment: An update from the last decades

Heart failure (HF) is a major global health problem afflicting millions worldwide. Despite the significant advances in therapies and prevention, HF still carries very high morbidity and mortality, requiring enormous healthcare-related expenditure, and the search for new weapons goes on. Following initial treatment strategies targeting inotropism and congestion, attention has focused on offsetting the neurohormonal overactivation and three main therapies, including angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor antagonists, β-adrenoceptor antagonists, and mineralocorticoid receptor antagonists, have been the foundation of standard treatment for patients with HF. Recently, a paradigm shift, including angiotensin receptor-neprilysin inhibitor, sodium glucose co-transporter 2 inhibitor, and ivabradine, has been added. Moreover, soluble guanylate cyclase stimulator, elamipretide, and omecamtiv mecarbil have come out as a next-generation therapeutic agent for patients with HF. Although these pharmacologic therapies have been significantly successful in relieving symptoms, there is still no complete cure for HF. We may be currently entering a new era of treatment for HF with animal experiments and human clinical trials assessing the value of antibody-based immunotherapy and gene therapy as a novel therapeutic strategy. Such tempting therapies still have some challenges to be addressed but may become a weighty option for treatment of HF. This review article will compile the paradigm shifts in HF treatment over the past dozen years or so and illustrate current landscape of antibody-based immunotherapy and gene therapy as a new therapeutic algorithm for patients with HF.

Evaluation of ivabradine plus beta-blocker versus beta-blocker alone in addition to standard care in reducing hospitalization and major adverse cardiovascular event in patients with chronic heart failure: a prospective observational study in tertiary care hospital in central India

BACKGROUND

In recent years, there has been an increase in cases of heart failure, ultimately leading to an increase in hospitalization for heart failure (HF) and cardiovascular mortality. The aim of our study was to evaluate ivabradine combined with beta-blocker versus beta-blocker alone in addition to standard care for chronic heart failure, followed for a period of 6 months for the rate of hospitalization and major adverse cardiovascular event (MACE) in patients with reduced left ventricular ejection fraction (LVEF < 35%).

RESULTS

A total of 64 patients were included in this observational study with 30 patients in the ivabradine + beta-blocker (IVA + BB) group and 34 in the beta-blocker (BB) group. The median (IQR) age of the study sample was 57 (50-62) and 58.5 (55-67) in IVA + BB and BB groups, respectively, with LVEF < 35%. The incidence of the primary endpoint of composite MACE (MI, stroke, death, worsening of HF) was 5 in both groups. The mean heart rate was significantly decreased (p < 0.001) at 3-month and 6-month follow-up from baseline in the ivabradine + beta-blocker group as compared to the beta-blocker group alone, while it significantly increased in the beta-blocker group at 3 months (p < 0.01) and also at sixth months (p < 0.05). Parameters such as the New York Heart Association (NYHA) class and the Minnesota Living with Heart Failure questionnaire (MLWHFQ) were also assessed but did not show significant change.

CONCLUSION

Overall, observations from the study results show that IVA + BB seems to be overall well tolerated in the study sample, with a somewhat smaller decrease in hospitalization and a delay in MACE events in the sample population enrolled in a tertiary care hospital in India. Further exploration in a larger sample is required concerning the Indian population.

Drug repurposing: A multi targetted approach to treat cardiac disease from existing classical drugs to modern drug discovery

Cardiovascular diseases (CVDs) are characterized by abnormalities in the heart, blood vessels, and blood flow. CVDs comprise a diverse set of health issues. There are several types of CVDs like stroke, endothelial dysfunction, thrombosis, atherosclerosis, plaque instability and heart failure. Identification of a new drug for heart disease takes longer duration and its safety efficacy test takes even longer duration of research and approval. This chapter explores drug repurposing, nano-therapy, and plant-based treatments for managing CVDs from existing drugs which saves time and safety issues with testing new drugs. Existing drugs like statins, ACE inhibitor, warfarin, beta blockers, aspirin and metformin have been found to be useful in treating cardiac disease. For better drug delivery, nano therapy is opening new avenues for cardiac research by targeting interleukin (IL), TNF and other proteins by proteome interactome analysis. Nanoparticles enable precise delivery to atherosclerotic plaques, inflammation areas, and damaged cardiac tissues. Advancements in nano therapeutic agents, such as drug-eluting stents and drug-loaded nanoparticles are transforming CVDs management. Plant-based treatments, containing phytochemicals from Botanical sources, have potential cardiovascular benefits. These phytochemicals can mitigate risk factors associated with CVDs. The integration of these strategies opens new avenues for personalized, effective, and minimally invasive cardiovascular care. Altogether, traditional drugs, phytochemicals along with nanoparticles can revolutionize the future cardiac health care by identifying their signaling pathway, mechanism and interactome analysis.

Pacemaker Channels and the Chronotropic Response in Health and Disease

Loss or dysregulation of the normally precise control of heart rate via the autonomic nervous system plays a critical role during the development and progression of cardiovascular disease-including ischemic heart disease, heart failure, and arrhythmias. While the clinical significance of regulating changes in heart rate, known as the chronotropic effect, is undeniable, the mechanisms controlling these changes remain not fully understood. Heart rate acceleration and deceleration are mediated by increasing or decreasing the spontaneous firing rate of pacemaker cells in the sinoatrial node. During the transition from rest to activity, sympathetic neurons stimulate these cells by activating β-adrenergic receptors and increasing intracellular cyclic adenosine monophosphate. The same signal transduction pathway is targeted by positive chronotropic drugs such as norepinephrine and dobutamine, which are used in the treatment of cardiogenic shock and severe heart failure. The cyclic adenosine monophosphate-sensitive hyperpolarization-activated current (If) in pacemaker cells is passed by hyperpolarization-activated cyclic nucleotide-gated cation channels and is critical for generating the autonomous heartbeat. In addition, this current has been suggested to play a central role in the chronotropic effect. Recent studies demonstrate that cyclic adenosine monophosphate-dependent regulation of HCN4 (hyperpolarization-activated cyclic nucleotide-gated cation channel isoform 4) acts to stabilize the heart rate, particularly during rapid rate transitions induced by the autonomic nervous system. The mechanism is based on creating a balance between firing and recently discovered nonfiring pacemaker cells in the sinoatrial node. In this way, hyperpolarization-activated cyclic nucleotide-gated cation channels may protect the heart from sinoatrial node dysfunction, secondary arrhythmia of the atria, and potentially fatal tachyarrhythmia of the ventricles. Here, we review the latest findings on sinoatrial node automaticity and discuss the physiological and pathophysiological role of HCN pacemaker channels in the chronotropic response and beyond.

Validation of a New Scoring Method to Assess the Efficacy of Rapid Initiation and Titration of Combination Pharmacotherapy for Patients Hospitalized with Acute Decompensated Heart Failure with Reduced and Mildly Reduced Ejection Fraction

Background: Despite the encouragement of early initiation and titration of guideline-directed medical therapy (GDMT) for the treatment of heart failure (HF), most patients do not receive an adequate type and dose of pharmacotherapy in the real world. Objectives: This study aimed to determine the efficacy of titrating composite GDMT in patients with HF with reduced and mildly reduced ejection fraction and to identify patient conditions that may benefit from titration of GDMT. Methods: This was a two-center, retrospective study of consecutive patients hospitalized with acute decompensated heart failure (ADHF). Patients were classified into two groups according to a scoring scale determined by combination and doses of four types of HF agents (ACEis/ARBs/ARNis, BBs, MRAs, and SGLT2is) at discharge. A score of 5 or greater was defined as titrated GDMT, and a score of 4 or less was regarded as sub-optimal medical therapy (MT). Results: A total of 979 ADHF patients were screened. After 553 patients were excluded based on exclusion criteria, 426 patients (90 patients in the titrated GDMT group and 336 patients in the sub-optimal MT group) were enrolled for the analysis. The median follow-up period was 612 (453-798) days. Following statistical adjustment using the propensity score weighting method, the 2-year composite endpoint (composite of cardiac death and HF rehospitalization) rate was significantly lower in the titrated GDMT group, at 19%, compared with the sub-optimal MT group: 31% (score 3-4 points) and 43% (score 0-2 points). Subgroup analysis indicated a marked benefit of titrated GDMT in particular patient subgroups: age < 80 years, BMI 19.0-24.9, eGFR > 20 mL/min/1.73 m2, and serum potassium level ≤ 5.5 mmol/L. Conclusions: Prompt initiation and dose adjustment of multiple HF medications, with careful monitoring of the patient's physiologic and laboratory values, is a prerequisite for improving the prognosis of patients with heart failure.

Ivabradine ameliorates cardiomyopathy progression in a Duchenne muscular dystrophy model rat

Duchenne muscular dystrophy (DMD) is an X-linked recessive myopathy caused by dystrophin mutations. Inevitable progressive cardiomyopathy is a current leading cause of premature death although respiratory management has improved the prognosis of patients with DMD. Recent evidence shows that reducing the heart rate is expected as one of the promising strategies for heart failure treatment, but administering a sufficient dose of β-blocker for patients with DMD with tachycardia is difficult because of their low blood pressure (BP). Thus, this study aimed to clarify the role of ivabradine, which suppresses cardiac sinus node pacemakers without decreasing BP, in ameliorating cardiomyopathy progression in a rat model with DMD. A trans-oral single ivabradine administration demonstrated a declined dose-dependent heart rate without any significant BP reduction. Trans-gastric repeated administrations of 5 mg/kg of ivabradine twice a day for 3 months showed ameliorated cardiomyopathy in DMD rats based on echocardiography and histopathological observations (left ventricular dysfunction, right ventricular dysfunction, and myocardial fibrosis) as compared with vehicle administration.Our finding indicates that ivabradine is expected as another treatment choice for patients with DMD having tachycardia.

Optimal Medical Therapy for Stable Ischemic Heart Disease: Focus on Anti-anginal Therapy

Chronic coronary disease (CCD) is a major cause of morbidity and mortality worldwide. The most common symptom of CCD is exertional angina pectoris, a discomfort in the chest that commonly occurs during activities of daily life. Patients are dismayed by recurring episodes of angina and seek medical help in preventing or minimizing episodes. Angina occurs when the coronary arteries are unable to supply sufficient blood flow to the cardiac muscle to meet the metabolic needs of the left ventricular myocardium. While lifestyle changes and aggressive risk factor modification play a critical role in the management of CCD, management of angina usually requires pharmacologic therapy. Medications such as beta-blockers, calcium channel blockers, nitrates, ranolazine, and others ultimately work to improve the mismatch between myocardial blood flow and metabolic demand. This manuscript briefly describes the pathophysiologic basis for symptoms of angina, and how currently available anti-anginal therapies contribute to preventing or minimize the occurrence of angina.

Advancing Guideline-Directed Medical Therapy in Heart Failure: Overcoming Challenges and Maximizing Benefits

The delayed titration of guideline-directed drug therapy (GDMT) is a complex event influenced by multiple factors that often result in poor prognosis for patients with heart failure (HF). Individualized adjustments in GDMT titration may be necessary based on patient characteristics, and every clinician is responsible for promptly initiating GDMT and titrating it appropriately within the patient's tolerance range. This review examines the current challenges in GDMT implementation and scrutinizes titration considerations within distinct subsets of HF patients, with the overarching goal of enhancing the adoption and effectiveness of GDMT. The authors also underscore the significance of establishing a novel management strategy that integrates cardiologists, nurse practitioners, pharmacists, and patients as a unified team that can contribute to the improved promotion and implementation of GDMT.

Sex differences in achieving guideline-recommended heart rate control among a large sample of patients at risk for sudden cardiac arrest

Background

Despite known clinical benefits, guideline-recommended heart rate (HR) control is not achieved for a significant proportion of patients with HF with reduced ejection fraction. The wearable cardioverter-defibrillator (WCD) provides continuous HR monitoring and alerts that could aid medication titration.

Objective

This study sought to evaluate sex differences in achieving guideline-recommended HR control during a period of WCD use.

Methods

Data from patients fitted with a WCD from 2015 to 2018 were obtained from the manufacturer's database (ZOLL). The proportion of patients with adequate nighttime resting HR control at the beginning of use (BOU) and at the end of use (EOU) were compared by sex. Adequate HR control was defined as having a nighttime median HR <70 beats/min.

Results

A total of 21,440 women and a comparative sample of 17,328 men (median 90 [IQR 59-116] days of WCD wear) were included in the final dataset. Among patients who did not receive a shock, over half had insufficient HR control at BOU (59% of women, 53% of men). Although the proportion of patients with resting HR ≥70 beats/min improved by EOU, 43% of women and 36% of men did not achieve guideline-recommended HR control.

Conclusion

A significant proportion of women and men did not achieve adequate HR control during a period of medical therapy optimization. Compared with men, a greater proportion of women receiving WCD shocks had insufficiently controlled HR in the week preceding ventricular tachyarrhythmia/ventricular fibrillation and 43% of nonshocked women, compared with 36% of men, did not reach adequate HR control during the study period. The WCD can be utilized as a remote monitoring tool to record HR and inform adequate uptitration of beta-blockers, with particular focus on reducing the treatment gap in women.

SGLT2 inhibitors: from glucose-lowering to cardiovascular benefits

An increasing number of individuals are at high risk of type 2 diabetes (T2D) and its cardiovascular complications, including heart failure (HF), chronic kidney disease (CKD), and eventually premature death. The sodium-glucose co-transporter-2 (SGLT2) protein sits in the proximal tubule of human nephrons to regulate glucose reabsorption and its inhibition by gliflozins represents the cornerstone of contemporary T2D and HF management. Herein, we aim to provide an updated overview of the pleiotropy of gliflozins, provide mechanistic insights and delineate related cardiovascular (CV) benefits. By discussing contemporary evidence obtained in preclinical models and landmark randomized controlled trials, we move from bench to bedside across the broad spectrum of cardio- and cerebrovascular diseases. With landmark randomized controlled trials confirming a reduction in major adverse CV events (MACE; composite endpoint of CV death, non-fatal myocardial infarction, and non-fatal stroke), SGLT2 inhibitors strongly mitigate the risk for heart failure hospitalization in diabetics and non-diabetics alike while conferring renoprotection in specific patient populations. Along four major pathophysiological axes (i.e. at systemic, vascular, cardiac, and renal levels), we provide insights into the key mechanisms that may underlie their beneficial effects, including gliflozins' role in the modulation of inflammation, oxidative stress, cellular energy metabolism, and housekeeping mechanisms. We also discuss how this drug class controls hyperglycaemia, ketogenesis, natriuresis, and hyperuricaemia, collectively contributing to their pleiotropic effects. Finally, evolving data in the setting of cerebrovascular diseases and arrhythmias are presented and potential implications for future research and clinical practice are comprehensively reviewed.

Novel Medical Treatments and Devices for the Management of Heart Failure with Reduced Ejection Fraction

Heart failure (HF) is a growing issue in developed countries; it is often the result of underlying processes such as ischemia, hypertension, infiltrative diseases or even genetic abnormalities. The great majority of the affected patients present a reduced ejection fraction (≤40%), thereby falling under the name of "heart failure with reduced ejection fraction" (HFrEF). This condition represents a major threat for patients: it significantly affects life quality and carries an enormous burden on the whole healthcare system due to its high management costs. In the last decade, new medical treatments and devices have been developed in order to reduce HF hospitalizations and improve prognosis while reducing the overall mortality rate. Pharmacological therapy has significantly changed our perspective of this disease thanks to its ability of restoring ventricular function and reducing symptom severity, even in some dramatic contexts with an extensively diseased myocardium. Notably, medical therapy can sometimes be ineffective, and a tailored integration with device technologies is of pivotal importance. Not by chance, in recent years, cardiac implantable devices witnessed a significant improvement, thereby providing an irreplaceable resource for the management of HF. Some devices have the ability of assessing (CardioMEMS) or treating (ultrafiltration) fluid retention, while others recognize and treat life-threatening arrhythmias, even for a limited time frame (wearable cardioverter defibrillator). The present review article gives a comprehensive overview of the most recent and important findings that need to be considered in patients affected by HFrEF. Both novel medical treatments and devices are presented and discussed.

Activated rate-response is associated with increased mortality risk in cardiac device carriers with acute heart failure

AIMS

This study investigated whether an activated R-mode in patients carrying a cardiac implantable electronic device (CIED) is associated with worse prognosis during and after an episode of acutely decompensated heart failure (AHF).

METHODS

Six hundred and twenty-three patients participating in an ongoing prospective cohort study that phenotypes and follows patients admitted for AHF were studied. We compared CIED carriers with activated R-mode stimulation (CIED-R) to CIED carriers not in R-mode (CIED-0) and patients without CIEDs (no-CIED). The independent impact of R-mode activation on 12-month all-cause death was examined using uni- and multivariable Cox proportional hazards regression taking into account potential confounders, and hazard ratios (HR) with their 95% confidence intervals (CI) were reported.

RESULTS

Mean heart rate on admission was lower in CIED-R (n = 37, 16% women) vs. CIED-0 (n = 64, 23% women) or no-CIED (n = 511, 43% women): 70 bpm vs. 80 bpm or 82 bpm; both p<0.001. In-hospital mortality was similar across groups, but age- and sex-adjusted all-cause 12-month mortality risk was differentially affected by R-mode activation; CIED-R vs. CIED-0: HR 2.44, 95%CI 1.25-4.74; CIED-R vs. no-CIED: HR 2.61, 95%CI 1.59-4.29. These effects persisted after multivariable adjustment for potential confounders. Within CIED-R, mortality risk was similar in patients with pacemakers vs. ICDs and in subgroups with left ventricular ejection fraction (LVEF) <50% vs. ≥50%.

CONCLUSION

In patients admitted with AHF, R-mode stimulation was associated with a significantly increased 12-month mortality risk. Our findings shed new light on "admission heart rate" as a potentially treatable target in AHF. Our data are compatible with the concept that chronotropic incompetence contributes to an adverse outcome in these patients and may not be adequately treated through accelerometer-based R-mode stimulation.

The Impact of Potassium Dynamics on Cardiomyocyte Beating in Hemodialysis Treatment

Background: Observational studies of intermittent hemodialysis therapy have reported that the excess decrease in K+ concentration in plasma (KP) during treatment is associated with the destabilization of cardiac function. Elucidating the mechanism by which the decrease in KP impairs myocardial excitation is indispensable for a deeper understanding of prescription design. Methods: In this study, by using an electrophysiological mathematical model, we investigated the relationship between KP dynamics and cardiomyocyte excitability for the first time. Results: The excess decrease in KP during treatment destabilized cardiomyocyte excitability through the following events: (1) a decrease in KP led to the prolongation of the depolarization phase of ventricular cells due to the reduced potassium efflux rate of the Kr channel, temporarily enhancing contraction force; (2) an excess decrease in KP activated the transport of K+ and Na+ through the funny channel in sinoatrial nodal cells, disrupting automaticity; (3) the excess decrease in KP also resulted in a significant decrease in the resting membrane potential of ventricular cells, causing contractile dysfunction. Avoiding an excess decrease in KP during treatment contributed to the maintenance of cardiomyocyte excitability. Conclusions: The results of these mathematical analyses showed that it is necessary to implement personal prescription or optimal control of K+ concentration in dialysis fluid based on predialysis KP from the perspective of regulatory science in dialysis treatment.

Cirrhotic cardiomyopathy: Pathogenesis, clinical features, diagnosis, treatment and prognosis

Cardiac dysfunction among cirrhotic patients has long been recognized in the medical community. While it was originally believed to be a direct result of alcohol toxicity, in the last 30 years cirrhotic cardiomyopathy (CCM) has been described as a syndrome characterized by chronic cardiac dysfunction in cirrhotic patients in the absence of known cardiac disease, regardless of the etiology of cirrhosis. CCM occurs in about 60% of patients with cirrhosis and plays a critical role in disease progression and treatment outcomes. Due to its predominantly asymptomatic course, diagnosing CCM is challenging and requires a high index of suspicion and a multiparametric approach. Patients with CCM usually present with the following triad: impaired myocardial contractile response to exercise, inadequate ventricular relaxation, and electrophysiological abnormalities (notably prolonged QT interval). In recent years, research in this area has grown expeditiously and a new set of diagnostic criteria has been developed by the Cirrhotic Cardiomyopathy Consortium, to properly identify patients with CCM. Nevertheless, CCM is still largely unknown among clinicians, and a major part of its pathophysiology and treatment is yet to be understood. In the present work, we aim to compile and summarize the available data on the pathogenesis, clinical features, diagnosis, treatment, and prognosis of CCM.