Heart rate: a prognostic factor and therapeutic target in chronic heart failure. The distinct roles of drugs with heart rate-lowering properties

Daily Affect and Daily Prospective Memory in People after Stroke and Their Partners: The Moderating Role of Resting Heart Rate

INTRODUCTION

Experimental research suggests that affect may influence prospective memory performance, but real-life evidence on affect-prospective memory associations is limited. Moreover, most studies have examined the valence dimension of affect in understanding the influence of affect on cognitive performance in daily life, with insufficient consideration of the arousal dimension. To maximize ecological validity, the current study examined the relationships between daily affect and daily prospective memory using repeated daily assessments and the role of resting heart rate on these relationships. We examined both valence and arousal of daily affect by categorizing affect into four dimensions: high-arousal positive affect, low-arousal positive affect, high-arousal negative affect, and low-arousal negative affect.

METHOD

We examined existing data collected from community-dwelling couples, of which at least one partner had a stroke history. The analytic sample included 111 adults (Mage = 67.46 years, SD = 9.64; 50% women) who provided 1,274 days of data. Among the participants, 58 were living with the effects of a stroke and 53 were partners. Participants completed daily event-based prospective memory tasks (in morning and/or evening questionnaires), reported daily affect in the evening, and wore a wrist-based Fitbit device to monitor resting heart rate over 14 consecutive days.

RESULTS

Results from multilevel models show that, within persons, elevated high-arousal negative affect was associated with worse daily prospective memory performance. In addition, lower resting heart rate attenuated the inverse association between high-arousal negative affect and lowered prospective memory performance. We did not find significant associations of high- or low-arousal positive affect and low-arousal negative affect with daily prospective memory.

DISCUSSION

Our findings are in line with the resource allocation model and the cue-utilization hypothesis in that high-arousal negative affect is detrimental to daily prospective memory performance. Lower resting heart rate may buffer individuals' prospective memory performance from the influence of high-arousal negative affect. These findings are consistent with the neurovisceral integration model on heart-brain connections, highlighting the possibility that cardiovascular fitness may help maintain prospective memory into older adulthood.

SMOC2 plays a role in heart failure via regulating TGF-β1/Smad3 pathway-mediated autophagy

Heart failure (HF) is a major global cause of morbidity and mortality. This study aimed to elucidate the role of secreted protein acidic and rich in cysteine-related modular calcium-binding protein 2 (SMOC2) in HF development and its underlying mechanism. Using a rat HF model, SMOC2 expression was examined and then knocked down via transfection to assess its impact on cardiac function and damage. The study also evaluated the effects of SMOC2 knockdown on autophagy-related molecules and the transforming growth factor beta 1 (TGF-β1)/SMAD family member 3 (Smad3) signaling pathway. Intraperitoneal injection of the TGF-β agonist (SRI-011381) into the HF rat model was performed to explore the SMOC2-TGF-β1/Smad3 pathway relationship. SMOC2 expression was elevated in HF rats, while its downregulation improved cardiac function and damage. SMOC2 knockdown reversed alterations in the LC3-II/I ratio, Beclin-1, and p62 levels in HF rats. Through transmission electron microscope, we observed that SMOC2 knockdown restored autophagosome levels. Furthermore, SMOC2 downregulation inhibited the TGF-β1/Smad3 signaling pathway, which was counteracted by SRI-011381. In conclusion, SMOC2 knockdown inhibits HF development by modulating TGF-β1/Smad3 signaling-mediated autophagy, suggesting its potential as a therapeutic target for HF.

ETS2 promotes cardiomyocyte apoptosis and autophagy in heart failure by regulating lncRNA TUG1/miR-129-5p/ATG7 axis

Heart failure (HF) is a chronic disease in which the heart is unable to provide enough blood and oxygen to the peripheral tissues. Cardiomyocyte apoptosis and autophagy have been linked to HF progression. However, the underlying mechanism of HF is unknown. In this study, H₂ O₂ -treated AC16 cells were used as a cell model of HF. The mRNA and protein levels of related genes were examined using RT-qPCR and western blot. Cell viability and apoptosis were assessed using CCK-8 and flow cytometry, respectively. The interactions between ETS2, TUG1, miR-129-5p, and ATG7 were validated by luciferase activity, ChIP, and RNA-Binding protein Immunoprecipitation assays. According to our findings, H₂ O₂ stimulation increased the expression of ETS2, TUG1, and ATG7 while decreasing the expression of miR-129-5p in AC16 cells. Furthermore, H₂ O₂ stimulation induced cardiomyocyte apoptosis and autophagy, which were reversed by ETS2 depletion, TUG1 silencing, or miR-129-5p upregulation. Mechanistically, ETS2 promoted TUG1 expression by binding to the TUG1 promoter, and TUG1 sponged miR-129-5p to increase ATG7 expression. Furthermore, TUG1 overexpression reversed ETS2 knockdown-mediated inhibition of cardiomyocyte apoptosis and autophagy and miR-129-5p inhibition abolished TUG1 depletion-mediated suppression of cardiomyocyte apoptosis and autophagy in H₂ O₂ -induced AC16 cells. As presumed, ATG7 overexpression reversed miR-129-5p mimics-mediated repression of cardiomyocyte apoptosis and autophagy in H₂ O₂ -induced AC16 cells. Finally, ETS2 silencing reduced cardiomyocyte apoptosis and autophagy to slow HF progression by targeting the ETS2/TUG1/miR-129-5p/ATG7 axis, which may provide new therapeutic targets for HF treatment.

IVABRADINE-INDUCED HEART RATE REDUCTION INCREASES THE SEVERITY OF POSTRESUSCITATION MYOCARDIAL DYSFUNCTION IN A RAT MODEL OF CARDIOPULMONARY RESUSCITATION

ABSTRACT

Aims: A rapid heart rate (HR) that occurs after cardiopulmonary resuscitation (CPR) is a short-term compensatory mechanism preserving cardiac output. However, if of long duration, it is unfavorable for myocardial function postresuscitation because of disrupted balance between myocardial oxygen supply and demand. This raises the assumption that such a sustained fast HR should be regulated. The present study aimed to investigate the follow-on effect of ivabradine (a specific inhibitor of the I f current of the sinoatrial node)-induced HR reduction (HRR) on postresuscitation myocardial function in a rat model of CPR. Methods and results: Six minutes of ventricular fibrillation and 8 min of CPR were performed on Sprague-Dawley rats. All 32 resuscitated animals were then randomized into saline and ivabradine groups, each group having nonsurvival and survival subgroups (n = 8 each). Saline or ivabradine (0.5 mL/kg) was administered at 1 h postresuscitation. Heart rate, myocardial function as expressed by cardiac output, ejection fraction, and myocardial performance index were assessed at baseline and hourly from 1 to 5 h postresuscitation. Heart rate variability was analyzed at baseline and at 1, 3, and 5 h postresuscitation. Serum epinephrine and cardiac troponin I at baseline and at 1, 3, and 5 h postresuscitation in nonsurvival subgroup were measured. Survival duration in the survival subgroup was observed. The baseline HR was approximately 390 beats/min (bpm). After resuscitation, an average increase of Δ ≈ +15 bpm (relative ratio ≈ +3.8%) with a resultant HR of 405 bpm lasting more than 5 h occurred. Ivabradine group achieved a steady HRR of Δ ≈ -30 bpm (relative ratio ≈ -7.4%) as compared with saline group ( P < 0.01). Postresuscitation myocardial function was significantly worse in the ivabradine group (all P < 0.01). Heart rate variability was significantly impaired in the ivabradine group (all P < 0.05). Serum cardiac troponin I and epinephrine concentration were significantly higher in the ivabradine group (all P < ?0.01). Survival duration was significantly shortened in the ivabradine group as compared with the saline group (388 vs. 526 min, P < ?0.01). Conclusions: Ivabradine-induced HRR increases the severity of postresuscitation myocardial dysfunction and shortens survival duration in a rat model of CPR.

Mining Potential Drug Targets and Constructing Diagnostic Models for Heart Failure Based on miRNA-mRNA Networks

Heart failure (HF) is a globally prevalent cardiovascular disease, but effective drug targets and diagnostic models are still lacking. This study was designed to investigate effective drug targets and diagnostic models for HF in terms of miRNA targets, hoping to contribute to the understanding and treatment of HF. Using HF miRNA and gene expression profile data from the GEO database, we analyzed differentially expressed miRNAs/gene identification in HF using Limma and predicted miRNA targets by the online TargetScan database. Subsequently, gene set enrichment analysis and annotation were performed using WebGestaltR package. Protein-protein interactions were identified using the STRING database. The proximity of drugs to treat HF was also calculated and predicted for potential target therapeutic drug. In addition, further drug identification was performed by molecular docking. Finally, diagnostic models were constructed based on differential miRNAs. The GEO dataset was used to screen 66 differentially expressed miRNAs, incorporating 56 downregulated miRNAs and 10 upregulated miRNAs. The JAK-STAT signaling pathway, MAPK signaling pathway, p53 signaling pathway, Prolactin signaling pathway, and TGF-beta signaling pathway were enriched, as shown by KEGG enrichment analysis on the target genes. In addition, we found that 83 genes were upregulated and 92 genes were downregulated in HF patients vs. healthy individuals. Based on the inflammation-related score, hypoxia-related score, and energy metabolism-related score, we identified key miRNA-mRNA pairs and constructed an interaction network. Following that, TAP1, which had the highest expression and network connectivity in acute HF with crystal and molecular docking studies, was selected as a key candidate gene in the network. And the compound DB04847 was selected to produce a large number of favorable interactions with TAP1 protein. Finally, we constructed two diagnostic models based on the differential miRNAs hsa-miR-6785-5p and hsa-miR-4443. In conclusion, we identified TAP1, a key candidate gene in the diagnosis and treatment of HF, and determined that compound DB04847 is highly likely to be a potential inhibitor of TAP1. The TAP1 gene was also found to be regulated by hsa-miR-6785-5p and hsa-miR-4443, and a diagnostic model was constructed. This provides a new promising direction to improve the diagnosis, prognosis, and treatment outcome and guide more effective immunotherapy strategies of HF.

The association between cardiovascular drugs and depression/anxiety in patients with cardiovascular disease: A meta-analysis

This study aimed to investigate the association between cardiovascular drugs and depression/anxiety in patients with cardiovascular disease (CVD). This meta-analysis was registered in PROSPERO (International Prospective Register of Systematic Reviews; CRD42020197839) and conducted in accordance with the MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines. The PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure, Wanfang, and VIP databases were systematically searched to identify all available studies on this topic. Random-effects multivariate meta-regression was performed to investigate the sources of study heterogeneity. Review Manager version 5.3 and Stata 12.0 were used for data analyses. This meta-analysis included 54 studies with a total number of 212,640 patients. Overall, in patients with CVD, aspirin (odds ratio [OR]:0.91, 95% confidence interval [CI]:0.86-0.96, P = 0.02) was associated with a lower risk of depression, while calcium channel blockers (CCB) (OR:1.21, 95%CI:1.05-1.38, P = 0.008), diuretics (OR:1.34, 95%CI:1.14-1.58, P = 0.0005), and nitrate esters (OR:1.32, 95%CI:1.08-1.61, P = 0.006) were associated with a higher risk of depression, additionally, statin (OR:0.79, 95%CI:0.71-0.88, P < 0.0001) was associated with a lower risk of anxiety, but diuretics (OR:1.39, 95%CI:1.26-1.52, P < 0.00001) was associated with a higher risk of anxiety. Subgroup analysis presented that, in patients with hypertension, β-blockers were associated with a higher risk of depression (OR:1.45, 95%CI:1.26-1.67, P < 0.00001); in patients with coronary artery disease (CAD), statin (OR:0.77, 95%CI:0.59-0.99, P = 0.04), and aspirin (OR:0.85, 95%CI:0.75-0.97, P = 0.02) were associated with a lower risk of depression, while CCB (OR:1.32, 95%CI:1.15-1.51, P < 0.0001) and diuretics (OR:1.36, 95%CI:1.12-1.64, P = 0.002) were associated with a higher risk of depression, additionally, diuretics was associated with a higher risk of anxiety (OR:1.41, 95%CI:1.28-1.55, P < 0.00001); in patients with heart failure, nitrate esters (OR:1.93, 95%CI:1.19-3.13, P = 0.007), and diuretics (OR:1.58, 95%CI: 1.02-2.43, P = 0.04) were associated with a higher risk of depression. The use of cardiovascular drugs should be considered when evaluating depression or anxiety in patients with CVD to improve the care and treatment of these patients.

Novel lncRNA-miRNA-mRNA Competing Endogenous RNA Triple Networks Associated Programmed Cell Death in Heart Failure

Objective: Increasing evidence has uncovered the roles of lncRNA-miRNA-mRNA regulatory networks in cardiovascular diseases. However, the crosstalk between ceRNA networks and development of heart failure (HF) remains unclear. This study was to investigate the role of lncRNA-mediated ceRNA networks in the pathophysiological process of HF and its potential regulatory functions on programmed cell death.

Methods: We firstly screened the GSE77399, GSE52601 and GSE57338 datasets in the NCBI GEO database for screening differentially expressed lncRNAs, miRNAs and mRNAs. lncRNA-miRNA-mRNA regulatory networks based on the ceRNA theory were subsequently constructed. GO and KEGG enrichment analysis was conducted to predict potential biological functions of mRNAs in ceRNA networks. Differentially expressed mRNAs were then interacted with programmed cell death related genes. lncRNA-mediated ceRNA regulatory pathways on programmed cell death were validated with qRT-PCR testing.

Results: Based on our bioinformatic analysis, two lncRNAs, eight miRNAs and 65 mRNAs were extracted to construct two lncRNAs-mediated ceRNA networks in HF. Biological processes and pathways were enriched in extracellular matrix. Seven lncRNA-mediated ceRNA regulatory pathways on programmed cell death, GAS5/miR-345-5p/ADAMTS4, GAS5/miR-18b-5p/AQP3, GAS5/miR-18b-5p/SHISA3, GAS5/miR-18b-5p/C1orf105, GAS5/miR-18b-5p/PLIN2, GAS5/miR-185-5p/LPCAT3, and GAS5/miR-29b-3p/STAT3, were finally validated.

Conclusions: Two novel ceRNA regulatory networks in HF were discovered based on our bioinformatic analysis. Based on the interaction and validation analysis, seven lncRNA GAS5-mediated ceRNA regulatory pathways were hypothesized to impact programmed cell death including seven for apoptosis, three for ferroptosis, and one for pyroptosis. Upon which, we provided novel insights and potential research plots for bridging ceRNA regulatory networks and programmed cell death in HF.

Cardiac medication management in Duchenne muscular dystrophy

There have been significant improvements in the skeletal muscle and respiratory care for patients with Duchenne muscular dystrophy (DMD) over the last two decades. This has resulted in longer expected survival as many patients will live into their 20s and 30s. This timeline has resulted in a greater proportion of patients experiencing heart failure and cardiac-related mortality. Herein, we describe the current indications for medical therapy for patients with DMD.

Updates in pharmacotherapy of heart failure with reduced ejection fraction

Heart failure is a common entity encountered in healthcare with a vast socioeconomic impact. Recent advances in pharmacotherapy have led to the development of novel therapies with mortality benefits, improvement in heart failure symptoms and hospitalizations. This article is intended to explore those newer pharmacotherapies and summarize the evidence behind guideline directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF). It has been several years since any significant advances in pharmacotherapy of heart failure have resulted in survival benefit. Angiotensin-neprilysin inhibitors through the PARADIGM-HF and PIONEER-HF trials have shown mortality benefits and a reduction in heart failure hospitalizations and are considered landmark trials in heart failure. Vericiguat is an oral guanylate cyclase stimulator that through the recent VICTORIA trial showed a 10% relative difference in death from cardiovascular cause or hospitalization for heart failure. The sodium-glucose transport protein 2 (SGLT2) inhibitors are another class of medications that have shown promise in the treatment of patients with HFrEF and diabetes mellitus. The CANVAS and EMPA-REG OUTCOME trials showed the potential benefit of SGLT2 inhibitors on cardiovascular mortality, DECLARE-TIMI 58 trial showed that treatment with dapagliflozin reduced the risk of cardiovascular death or hospitalization for heart failure to a greater extent in patients with reduced ejection fraction (EF). Although novel pharmacotherapy is the current focus of intense research, there have been numerous studies on potential benefit of iron supplementation in ferropenic patients with heart failure. Another rapidly expanding area of research in the realm of heart failure is precision medicine and its impact on the development, progression, and treatment of heart failure. The field of heart failure is dynamic and with the influx of data from recent and ongoing trials, newer therapies with morbidity and mortality benefits in HFrEF are now available, nonetheless, much work is still needed.

CARDIAC chronotropic effects of sleep-disordered breathing in patients with heart failure

It is still not known whether the oscillation in heart rate (HR) induced by sleep-disordered breathing (SDB) in patients with heart failure entails significant chronotropic effects. We hypothesised that since cyclical changes in ventilation and arterial blood gases during SDB affect HR through multiple and complexly interacting mechanisms characterised by large inter-subject variability, chronotropic effects may change from patient to patient. A total of 42 patients with moderate-to-severe chronic heart failure with systolic dysfunction underwent an in-hospital sleep study. Chronotropic effects of SDB were quantified by comparing the distribution of instantaneous HR during SDB with that during periods without SDB (noSDB) within the same night in each patient. Based on distribution changes from noSDB to SDB, 12, nine, 11, and 10 patients showed a significant tachycardic, bradycardic, tachycardic and bradycardic, and neither significant tachycardic nor significant bradycardic effect, respectively. Tachycardic and bradycardic effects were primarily due to an increase in the rate rather than in the magnitude of cyclical HR elevations and reductions, and were more prevalent and severe in patients with dominant obstructive and central events, respectively. The apnea-hypopnea index did not differ between groups. Conversely, the time spent with an oxygen saturation of <90% was greater in the tachycardic and tachycardic-bradycardic groups compared to the bradycardic group. These findings indicate that HR distribution changes induced by SDB can vary from patient to patient revealing four distinct and well-characterised chronotropic effects. These effects are related to the degree of hypoxic burden brought about by SDB and are affected by the type of sleep apnea (central/obstructive).

β-Blocker Doses and Heart Rate in Patients with Heart Failure: Results from the National Norwegian Heart Failure Registry

Background

Use of β-blockers and titration to the highest tolerated dose are highly recommended by the European Society of Cardiology (ESC) guidelines for treatment of chronic heart failure (HF) with a reduced ejection fraction (HFrEF), but little attention has been paid to the achieved heart rate (HR) during this treatment.

Objectives

The aim of the present study was to examine the achieved HR in relation to the use of β-blockers in these patients.

Methods

All of the patients (n = 2,689) in the National Norwegian Heart Failure Registry as part of the Norwegian Cardiovascular Disease Registry with a sinus rhythm and left ventricular ejection fraction (LVEF) <40% at stable follow-up visiting specialised hospital outpatient HF clinics in Norway were included. The β-blocker doses were calculated as a percent of the target dose according to ESC HF guidelines. Differences between baseline variables according to the achieved HR were analysed by the Student's t test for continuous variables and Pearson's χ² test for categorical variables. Linear regression was used to determine the predictors of HR ≥70 beats/min (bpm) in the multivariate analysis.

Results

One third of the patients had a resting HR ≥70 bpm. Of the patients with an HR ≥70 bpm, 72.3% used less than the target dose of β-blocker; they were younger and had a higher NYHA class, more diabetes mellitus and chronic obstructive pulmonary disease (COPD), and higher N-terminal pro-B type natriuretic peptide (NT-proBNP) levels and estimated glomerular filtration rates compared to the patients with an HR <70 bpm. The 1-year mortality was 3.1, 3.7, 5.8, and 9.1% among the patients with an HR <70, 70-79, 80-89, and >89 bpm, respectively. Only 2 patients used ivabradine.

Conclusions

In patients with HFrEF and sinus rhythm, an HR ≥70 bpm was associated with worse clinical variables and outcomes. A high proportion of the patients who had an HR ≥70 bpm was not treated with or/did not tolerate the target dose of a β-blocker, although the β-blocker dose was higher than in patients with an HR <70 bpm. This may suggest that increased efforts should be made to further increase the β-blocker dose, and treatment with ivabradine could be considered among patients with an HR ≥70 bpm.

Five-year results of heart rate control with ivabradine or metoprolol succinate in patients after heart transplantation

Background

Cardiac graft denervation causes inadequate sinus tachycardia in patients after heart transplantation (HTX) which is associated with reduced survival. This study investigated the 5-year results of heart rate control with ivabradine or metoprolol succinate in patients after HTX.

Methods

This registry study analyzed 104 patients receiving either ivabradine (n = 50) or metoprolol succinate (n = 54) within 5 years after HTX. Analysis included patient characteristics, medication, echocardiographic features, cardiac catheterization data, cardiac biomarkers, heart rates, and post-transplant survival including causes of death.

Results

Demographics and post-transplant medication revealed no significant differences except for ivabradine and metoprolol succinate use. At 5-year follow-up, patients with ivabradine had a significantly lower heart rate (73.3 bpm) compared to baseline (88.6 bpm; P < 0.01) and to metoprolol succinate (80.4 bpm; P < 0.01), a reduced left ventricular mass (154.8 g) compared to baseline (179.5 g; P < 0.01) and to metoprolol succinate (177.3 g; P < 0.01), a lower left ventricular end-diastolic pressure (LVEDP; 12.0 mmHg) compared to baseline (15.5 mmHg; P < 0.01) and to metoprolol succinate (17.1 mmHg; P < 0.01), and a reduced NT-proBNP level (525.4 pg/ml) compared to baseline (3826.3 pg/ml; P < 0.01) and to metoprolol succinate (1038.9 pg/ml; P < 0.01). Five-year post-transplant survival was significantly better in patients with ivabradine (90.0%) versus metoprolol succinate (68.5%; P < 0.01).

Conclusion

Patients receiving ivabradine showed a superior heart rate reduction and a better left ventricular diastolic function along with an improved 5-year survival after HTX.

Heart Failure: A Palliative Medicine Review of Disease, Therapies, and Medications With a Focus on Symptoms, Function, and Quality of Life

Despite significant advances in heart failure (HF) treatment, HF remains a progressive, extremely symptomatic, and terminal disease with a median survival of 2.1 years after diagnosis. HF often leads to a constellation of symptoms, including dyspnea, fatigue, depression, anxiety, insomnia, pain, and worsened cognitive function. Palliative care is an approach that improves the quality of life of patients and their caregivers facing the problems associated with life-threatening illness and therefore is well suited to support these patients. However, historically, palliative care has often focused on supporting patients with malignant disease, rather than a progressive chronic disease such as HF. Predicting mortality in patients with HF is challenging. The lack of obvious transition points in disease progression also raises challenges to primary care providers and specialists to know at what point to integrate palliative care during a patient's disease trajectory. Although therapies for HF often result in functional and symptomatic improvements including health-related quality of life (HRQL), some patients with HF do not demonstrate these benefits, including those patients with a preserved ejection fraction. Provision of palliative care for patients with HF requires an understanding of HF pathogenesis and common medications used for these patients, as well as an approach to balancing life-prolonging and HRQL care strategies. This review describes HF and current targeted therapies and their effects on symptoms, hospital admission rates, exercise performance, HRQL, and survival. Pharmacological interactions with and precautions related to commonly used palliative care medications are reviewed. The goal of this review is to equip palliative care clinicians with information to make evidence-based decisions while managing the balance between optimal disease management and patient quality of life.

Effects of Whey Protein Supplementation on Aortic Stiffness, Cerebral Blood Flow, and Cognitive Function in Community-Dwelling Older Adults: Findings from the ANCHORS A-WHEY Clinical Trial

ANCHORS A-WHEY was a 12-week randomized controlled trial (RCT) designed to examine the effect of whey protein on large artery stiffness, cerebrovascular responses to cognitive activity and cognitive function in older adults. Methods: 99 older adults (mean ± SD; age 67 ± 6 years, BMI 27.2 ± 4.7kg/m², 45% female) were randomly assigned to 50g/daily of whey protein isolate (WPI) or an iso-caloric carbohydrate (CHO) control for 12 weeks (NCT01956994). Aortic stiffness was determined as carotid-femoral pulse wave velocity (cfPWV). Aortic hemodynamic load was assessed as the product of aortic systolic blood pressure and heart rate (Ao SBP × HR). Cerebrovascular response to cognitive activity was assessed as change in middle-cerebral artery (MCA) blood velocity pulsatility index (PI) during a cognitive perturbation (Stroop task). Cognitive function was assessed using a computerized neurocognitive battery. Results: cfPWV increased slightly in CHO and significantly decreased in WPI (p < 0.05). Ao SBP × HR was unaltered in CHO but decreased significantly in WPI (p < 0.05). Although emotion recognition selectively improved with WPI (p < 0.05), WPI had no effect on other domains of cognitive function or MCA PI response to cognitive activity (p > 0.05 for all). Conclusions: Compared to CHO, WPI supplementation results in favorable reductions in aortic stiffness and aortic hemodynamic load with limited effects on cognitive function and cerebrovascular function in community-dwelling older adults.

Optimization of Heart Failure Treatment by Heart Rate Reduction

Heart failure (HF) treatment should be optimized in addition to guideline-directed and recommended drugs to achieve an appropriate heart rate (i.e. 50−60 bpm) by ivabradine in patients with a heart rate >70 bpm in sinus rhythm and with an ejection fraction ≤35%. Heart rate reduction was to reduce cardiovascular death and HF hospitalization dependent on baseline resting heart rate. In particular in patients at a heart rate >75 bpm, a reduction in cardiovascular death, all-cause death, HF death, HF hospitalization and all-cause hospitalization has been observed. The optimal heart rate achieved appears to be between 50−60 bpm, if well tolerated as in these patients the lowest event rate is observed on treatment. Heart rate reduction is, therefore, a treatable risk factor in chronic HF. Observational studies support the concept that it is a risk indicator in other cardiovascular and non-cardiovascular conditions. Whether heart rate reduction is also modifying risk in other conditions than chronic HF should be explored in prospective clinical trials.

Systolic blood pressure, heart rate, and outcomes in patients with coronary disease and heart failure

Aims

Data regarding the optimal systolic blood pressure (SBP) and heart rate (HR) for coronary artery disease (CAD) patients with hypertension and a history of heart failure (HF) are limited. Accordingly, using data from a large clinical trial, we investigated the association between SBP and heart rate and subsequent adverse outcomes in CAD patients with a history of HF, and we aimed to better understand how pre‐existing HF impacts outcomes among patients with CAD.

Methods and results

Among 22 576 CAD patients enrolled in the INternational VErapamil SR‐Trandolapril STudy (INVEST), 1256 were identified with a history of physician‐diagnosed HF New York Heart Association (NYHA) Class 1–3 at entry. The primary outcome was the first occurrence of all‐cause death, myocardial infarction (MI), or stroke. Cox proportional‐hazards models adjusted for pre‐specified covariates were constructed to estimate risk among the HF cohort compared with a case‐matched sample from the non‐HF cohort. At a mean 2.5 years' follow‐up, those with prior HF had a higher risk of the primary outcome (hazard ratio (HR) 2.55, 95% confidence interval 2.30–2.83, P < 0.0001). Among those with history of HF, a low (<120 mmHg) or high (>140 mmHg) SBP and heart rate ≥ 85 b.p.m. were associated with increased risk for adverse outcomes, which persisted after covariate adjustment.

Conclusions

In patients with CAD, a physician diagnosis of HF at baseline portended a higher risk for death, MI, or stroke than in those without an HF history. Achieving SBP of 120–140 mmHg and heart rate < 85 b.p.m. was associated with a better outcome in patients with known HF and CAD.

Kynurenic acid selectively reduces heart rate in spontaneously hypertensive rats

We found previously that intravenous kynurenic acid (KYNA), a native broad spectrum glutamate antagonist, increases renal blood flow and induces natriuresis in anesthetized spontaneously hypertensive rats (SHR). Since such changes may affect systemic circulation and can potentially find therapeutic application, in this study we examined long term influence of orally administered KYNA on systemic and renal hemodynamics and renal excretion in conscious SHR. KYNA was administered in drinking water at a dose of 25 mg/kg/day for 3 weeks. Heart rate (HR), systolic (SBP), and mean arterial pressure (MAP) were measured through telemetry. The records were taken at the beginning of the study (control, day 0), and then on day 7, 14, and 21 of treatment. Diuresis (V), total solute excretion (U_osmV), and sodium excretion (U_NaV) were determined on days 0, 7, and 14. KYNA consistently decreased HR, from 319 ± 8 to 291 ± 5, 299 ± 9 and 284 ± 6 beats/min on day 7, 14, and 21, respectively, (- 9, - 6, and - 11%; p < 0.01-0.0001); HR was stable in the solvent group. SBP, MAP, V, and U_NaV were not affected by KYNA, whereas U_osmV increased modestly. Chronic oral administration of KYNA to conscious SHR decreased HR without affecting MAP. Since tachycardia is an independent risk factor for cardiovascular disorders, and most drugs used to decrease HR have strong inotropic negative or hypotensive effect, such selective action seems of therapeutic potential. Moreover, food supplementation with KYNA can be considered in the prevention of heart diseases.

Serial heart rate measurement and mortality after acute heart failure

AIM

Heart failure (HF) poses a unique medical burden of high morbidity and mortality. Elevated resting heart rate (HR) is associated with worse outcomes in chronic HF, but little is known about the prognostic impact of serial HR measurement during hospital stay after acute HF. We examined the association between HR obtained at admission at Day 4 and at discharge and long-term mortality in a cohort of 672 patients discharge from hospital after management of acute HF.

METHODS AND RESULTS

All patients examined were in sinus rhythm. HR was derived from electrocardiogram and was defined as the first reported HR in the medical record. At 1 year follow up, 60 patients died. Median HR was 86 ± 17 b.p.m. (first tertile: 75 b.p.m., third tertile: 97 b.p.m.) at admission, 76 ± 14 b.p.m. (first tertile: 67 b.p.m., third tertile 85 b.p.m.) at Day 4, and 72 ± 11 b.p.m. (first tertile: 64 b.p.m., third tertile 80 b.p.m.) at discharge. Patients who died were significantly older (75 ± 11 vs. 71 ± 12 years; P = 0.027), had more frequently a history of ischemic cardiomyopathy (n = 34/60, P = 0.012) and of chronic obstructive pulmonary disease (n = 26/60, P = 0.027), had higher admission N terminal pro brain natriuretic peptide (14 572 ± 21 600 vs. 7647 ± 7964 pg/ml; P = 0.027), had lower systolic and diastolic blood pressures (P < 0.05), haemoglobin level (10.6 ± 2.2 vs. 12.2 ± 2.2 g/L; P = 0.005), albumin level (35.2 ± 4.3 vs 37.1 ± 4.1 g/dl; P = 0.003) and estimated glomerular filtration rate (47 ± 21 vs. 60 ± 28 ml/min/1.73 m² ; P = 0.0017). There were no significant differences between survivors and nonsurvivors in left ventricular ejection, the use of beta-blocker and angiotensin-converting enzyme-inhibitor, and the rate of comorbidities (hypertension, diabetes) (P=NS, for all). HR at admission was not significantly associated with 1 year mortality (P = 0.20), whereas there was a significant increase in 1 year mortality for HRs>85 b.p.m. at Day 4 (P < 0.0001) and > 80 b.p.m. at discharge (P < 0.0001). In the multivariable model that included the third tertile at Day 4 and discharge HR and adjusted for all other significant covariates, haemoglobin (P = 0.019), and HR at Day 4 (P = 0.023) were independently associated with 1 year mortality. When only discharge HR was included haemoglobin (P = 0.0004) and HR at discharge (P = 0.00053) remained independently associated with 1 year mortality.

CONCLUSIONS

In patients surviving the acute HF phase, a high HR at Day 4, and at a lesser degree at discharge, but not at admission, is a strong predictor of 1 year mortality.

Predictors and outcomes of atrial tachyarrhythmia among patients with implantable defibrillators

BACKGROUND

Atrial tachyarrhythmias (ATAs) are common among heart failure (HF) patients.

OBJECTIVE

The purpose of this study was to assess predictors for the development of new ATA and its components (atrial fibrillation/flutter [AF], supraventricular tachycardia [SVT]), and their association with subsequent clinical outcomes.

METHODS

We assessed predictors for first and recurrent ATA, AF, and SVT among 1500 patients in MADIT-RIT (Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy). We also investigated the association of new ATA, AF, or SVT with subsequent ventricular arrhythmia (VA), adverse events (HF hospitalization, syncope, or death), or death by time-dependent analysis.

RESULTS

During 17 months of follow-up, 286 patients (19%) developed new ATA, of whom 92 (6%) had AF and 194 (12%) had SVT. Younger age (≤65 years), diastolic blood pressure ≥72 mm Hg, heart rate ≥63 bpm, absence of diabetes, and prior atrial arrhythmia were independent predictors of ATA. Prior atrial arrhythmia was the only predictor of AF (hazard ratio 3.14; P <.001). New ATA was associated with significantly increased risk for subsequent VA (HR 2.12; P <.001), increased adverse events (HR 1.42; P <.001), and death (HR 1.85; P = .038). New AF and new SVT were both independently associated with >2-fold increased risk for the development of subsequent VA (HR 2.21; P = .012l and HR 2.15; P <.001, respectively) and adverse events.

CONCLUSION

Among MADIT-RIT patients, younger age, absence of diabetes, higher blood pressure, higher heart rate, and prior atrial arrhythmia predicted device-detected ATA. Both AF and SVT were associated with increased risk for subsequent VA and adverse events. Aggressive management should be considered in HF patients who develop new-onset, device-detected ATA to improve clinical outcomes.

Reconstruction and Analysis of the lncRNA-miRNA-mRNA Network Based on Competitive Endogenous RNA Reveal Functional lncRNAs in Dilated Cardiomyopathy

Dilated cardiomyopathy (DCM) is an important cause of sudden death and heart failure with an unknown etiology. Recent studies have suggested that long non-coding RNA (lncRNA) can interact with microRNA (miRNA) and indirectly interact with mRNA through competitive endogenous RNA (ceRNA) activities. However, the mechanism of ceRNA in DCM remains unclear. In this study, a miRNA array was first performed using heart samples from DCM patients and healthy controls. For further validation, we conducted real-time quantitative reverse transcription (RT)-PCR using samples from DCM patients and a doxorubicin-induced rodent model of cardiomyopathy, revealing that miR-144-3p and miR-451a were down-regulated, and miR-21-5p was up-regulated. Based on the ceRNA theory, we constructed a global triple network using data from the National Center for Biotechnology Information Gene Expression Omnibus (NCBI-GEO) and our miRNA array. The lncRNA-miRNA-mRNA network comprised 22 lncRNA nodes, 32 mRNA nodes, and 11 miRNA nodes. Hub nodes and the number of relationship pairs were then analyzed, and the results showed that two lncRNAs (NONHSAT001691 and NONHSAT006358) targeting miR-144/451 were highly related to DCM. Then, cluster module and random walk with restart for the ceRNA network were analyzed and identified four lncRNAs (NONHSAT026953/NONHSAT006250/NONHSAT133928/NONHSAT041662) targeting miR-21 that were significantly related to DCM. This study provides a new strategy for research on DCM or other diseases. Furthermore, lncRNA-miRNA pairs may be regarded as candidate diagnostic biomarkers or potential therapeutic targets of DCM.

The Importance of Heart Rate in Heart Failure and Reduced Ejection Fraction

BACKGROUND

Heart failure with reduced ejection fraction (HFrEF) is a progressive, chronic, and burdensome cardiovascular condition. It is associated with limiting symptoms, such as dyspnea and fatigue; a decline in functional capacity; and premature mortality and hospitalization. In heart failure (HF) management, heart rate is commonly assessed yet frequently overlooked as a modifiable risk factor and a predictor of mortality. An elevated heart rate increases myocardial demand and decreases diastolic filling time. Hospitalized patients with HFrEF who have a heart rate greater than 70 beats per minute at discharge were found to have lower survival rates.

PURPOSE

The aims of this study were to review the association between heart rate and clinical outcome in patients with HF and discuss the contribution of heart rate to HFrEF pathophysiology. Medications currently used to modulate heart rate in patients with HF are also reviewed.

CONCLUSIONS

In patients with HFrEF, an elevated heart rate contributes to HF progression, and it is both a prognostic and modifiable risk factor. Medications such as an evidence-based β-blockers, digoxin, and ivabradine are recommended for modulation of heart rate in patients with HFrEF.

CLINICAL IMPLICATIONS

Nurses play a pivotal role in managing HFrEF and must understand current evidence of the pathophysiology of elevated heart rate, risks, and management strategies. Early recognition of elevated heart rate and application of guideline-directed pharmacologic treatment for patients with HFrEF and an elevated heart rate remains key to improving patient outcomes.

Cardiovascular Effects of Liraglutide

BACKGROUND

Liraglutide is a glucagon-like 1 (GLP-1) agonist approved for treatment of type 2 diabetes and obesity.

OBJECTIVE

To review the cardiovascular effects of liraglutide including macrovascular and microvascular events, its use in heart failure, and its effects on heart rate and blood pressure.

RESULTS

The impact of liraglutide on cardiovascular outcomes was examined in a large welldesigned study published in 2016, the LEADER trial. This study included 9,340 patients with advanced type 2 diabetes and high baseline cardiovascular risk. The primary outcome was the first occurrence of death from cardiovascular causes, non-fatal myocardial infarction, or non-fatal stroke. After a median follow-up of 3.8 years, patients randomized to liraglutide had significant reduction in the composite primary outcome compared to patients randomized to placebo, hazard ratio (HR) 0.87; 95% CI 0.78-0.97. Death from cardiovascular causes was significantly reduced with liraglutide therapy (HR, 0.78; 95% CI 0.66-0.93), as well as death from any cause (HR, 0.85; 95% CI 0.74-0.97). In 2017, the LEADER investigators reported that nephropathy events were significantly lower after liraglutide therapy than placebo (HR 0.78; 95% CI 0.67-0.92), but there was no significant difference in retinopathy events. Meanwhile, other studies suggested that the use of liraglutide may be harmful in patients with severe heart failure, in part due to increase in heart rate.

CONCLUSION

Liraglutide is a useful therapy in patients with advanced type 2 diabetes complicated by cardiovascular disease, except patients with severe heart failure. Further studies are needed to evaluate the long-term effects of liraglutide, and to see whether its beneficial effects extend to patients with type 2 diabetes and low cardiac risk.

Heart rate, pulse pressure and mortality in patients with myocardial infarction complicated by heart failure

OBJECTIVE

To assess the relationship between heart rate (HR), pulse pressure (PP), and their association with mortality in a population of high-risk patients following acute myocardial infarction (MI).

METHODS

We performed an analysis in 22,398 patients included in "The High-Risk Myocardial Infarction Database Initiative", a database of clinical trials evaluating pharmacologic interventions in patients with MI complicated by signs of heart failure (HF) or left ventricular dysfunction. We found an interaction between HR and PP. Based on median HR and median PP, patients were divided in four categories: (1) HR < 75 bpm and PP ≥ 50 mm Hg (reference), (2) HR < 75 bpm and PP < 50 mm Hg, (3) HR ≥ 75 bpm and PP ≥ 50 mm Hg, and (4) HR ≥ 75 bpm and PP < 50 mm Hg. The association between these categories and outcomes was studied using a Cox proportional hazard model.

RESULTS

After a median follow-up of 24 (18-33) months, 3561 (16%) patients died of all-causes and 3048 (14%) patients of cardiovascular (CV) causes. In multivariate analysis, patients from the fourth category had the highest risk of all-cause mortality (hazard ratio of 1.69; 95% CI: 1.53-1.86) and CV mortality (hazard ratio of 1.78; 95% CI: 1.60-1.97).

CONCLUSIONS

There is an interaction between HR and PP in patients with HF following MI, with the highest risk being conferred by a clinical status with both an elevated HR and a lower PP. These findings identify a high-risk population likely to require an aggressive diagnostic and management strategy.

Prognosis of heart failure treated with digoxin or with ivabradine: A cohort study in the community

BACKGROUND

Resting heart rate (HR) reduction with ivabradine (IVA) improves outcomes of patients with heart failure and reduced ejection fraction (HFrEF). Nevertheless, the best option to slow HR in patients with HFrEF treated with beta-blockers and a HR >70 bpm is unsettled.

AIMS

To evaluate whether, in patients with HFrEF, commencing therapy with digoxin (CT-DIG) is associated to a worse prognosis than commencing treatment with ivabradine (CT-IVA).

METHODS

Observational study over 10 years on 2364 patients with HFrEF in sinus rhythm and a HR >70 bpm. Main outcomes were mortality, hospitalisations and visits. We analyse the independent relationship of CT-DIG or CT-IVA with the prognosis, stratifying patients for cardiovascular comorbidity, and for other potential confounders (378 patients who CT-DIG vs another 355 patients who CT-IVA vs another 1631 patients non-exposed to IVA or DIG).

RESULTS

During a median follow-up of 57.5 months, 1751 patients (74.1%) died, and 2151 (91.0%) were hospitalised for HF. CT-DIG or CT-IVA was associated with a lower all-cause mortality (DIG: HR = 0.86 [95% CI, 0.82-0.90], and IVA: HR = 0.88 [0.83-0.93]), cardiovascular mortality (DIG: HR = 0.84 [0.80-0.89] and IVA: HR = 0.83 [0.78-0.89]), hospitalisation (DIG: HR = 0.86 [0.83-0.89] and IVA: HR = 0.87 [0.83-0.91]) and 30-day readmission (DIG: HR = 0.84 [0.79-0.90] and IVA: HR = 0.88 [0.79-0.95]), after adjustment for cardiovascular comorbidity, and other potential confounders. These associations with the prognosis of HFrEF did not differ between patients who CT-DIG and those who CT-IVA.

CONCLUSION

Commencing therapy with digoxin or with ivabradine is associated with an improved prognosis of patients with HFrEF.

Acute Heart Rate-Dependent Hemodynamic Function of the Heart in the Post-Myocardial Infarction Rat Model: Change Over Time

BACKGROUND

Optimal heart rate (HR) for acute hemodynamic efficiency in heart failure (HF) is unknown.

METHODS

Wistar-Kyoto rats were followed-up for 3 and 7 days, 1 or 2 months after myocardial infarction (MI) or sham operation (ShO) and left ventricle (LV) pressure-volume (PV) loops were obtained at various HRs: baseline 400 beats per minute (bpm), reduced by ivabradine to 320 bpm, increased by atrial pacing to 480 bpm, under normal conditions and after preload increase (PI).

RESULTS

In the ShO group, PI augmented cardiac output (CO) by 55%, 67%, 84% at reduced, baseline, and increased HR, respectively. In post-MI rats, PI augmented CO 3 and 7 days, but not 1 and 2 months after MI. At increased HR, in response to PI, CO increased 3 and 7 days, tended to fall 1 and 2 months after MI; this hemodynamic response was salvaged by HR reduction. Further beneficial effects of HR reduction included reduction of LV end-diastolic pressure, increase of ejection fraction, contractility and relaxation velocity 1 and 2 months after MI.

CONCLUSIONS

In a rat HF model, optimal HR with regard to acute hemodynamic performance is shifted. Whereas in ShO rats increased HR facilitates CO increase induced by PI, in HF rats, such increase reduces CO, and HR reduction has beneficial effects. Thus, besides reducing progression of HF, HR-reducing interventions also offer immediate hemodynamic benefits.

Decreased autophagy induced by β1-adrenoceptor autoantibodies contributes to cardiomyocyte apoptosis

It has been recognized that myocardial apoptosis is one major factor in the development of heart dysfunction and autophagy has been shown to influence the apoptosis. In previous studies, we reported that anti-β₁-adrenergic receptor autoantibodies (β₁-AABs) decreased myocardial autophagy, but the role of decreased autophagy in cardiomyocyte apoptosis remains unclear. In the present study, we used a β₁-AAB-immunized rat model to investigate the role of decreased autophagy in cardiomyocyte apoptosis. We reported that the level of autophagic flux increased early and then decreased in an actively β₁-AAB-immunized rat model. Rapamycin, an mTOR inhibitor, restored myocardial apoptosis in the presence of β₁-AABs. Further, we found that the early increase of autophagy was an adaptive stress response that is possibly unrelated to β₁-AR, and the activation of the β₁-AR and PKA contributed to late decreased autophagy. Then, after upregulating or inhibiting autophagy with rapamycin, Atg5 overexpression adenovirus or 3-methyladenine in cultured primary neonatal rat cardiomyocytes, we found that autophagy decline promoted myocardial apoptosis effectively through the mitochondrial apoptotic pathway. In conclusion, the reduction of apoptosis through the proper regulation of autophagy may be important for treating patients with β₁-AAB-positive heart dysfunction.

Cardiac contractility modulation: a novel approach for the treatment of heart failure

Heart failure is a major health problem worldwide and, despite effective therapies, is expected to grow by almost 50 % over the next 15 years. Five-year mortality remains high at 50 % over 5 years. Because of the economic burden and large impact on quality of life, substantial effort has focused on treatments with multiple medical (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ARB), aldosterone antagonists, and combination of ARB/neprilysin blockers, ivabradine) and device therapies (ICD, CRT) which have been implemented to reduce disease burden and mortality. However, in the past decade only two new medical therapies and no devices have been approved by the US FDA for the treatment of heart failure. This review highlights the preclinical and clinical literature, and the implantation procedure, related to a relatively new therapeutic device for heart failure; cardiac contractility modulation (CCM). CCM delivers a biphasic high-voltage bipolar signal to the RV septum during the absolute refractory period, eliciting an acute increase in global contractility, and chronically producing a sustained improvement in quality of life, exercise tolerance, and heart failure symptoms. The technology is used commercially in Europe with nearly 3000 patients implanted worldwide. Indications include patients with reduced EF and normal or slightly prolonged QRS duration, thus filling an important therapeutic gap among the 2/3 of patients with heart failure who do not meet criteria for CRT. The mechanism by which CCM provides benefit can be seen at the cellular level where improved calcium handling (phosphorylation of phospholamban, upregulation of SERCA-2A), reversal of the fetal myocyte gene program associated with heart failure, and reverse remodeling are observed. Recent retrospective studies indicate a long-term mortality benefit. A pivotal randomized controlled study is currently being completed in the USA. CCM appears to be an effective, safe technology for the treatment of heart failure with reduced ejection fraction.

Characteristics, treatments and 1-year prognosis of hospitalized and ambulatory heart failure patients with chronic obstructive pulmonary disease in the European Society of Cardiology Heart Failure Long-Term Registry

AIMS

To describe the characteristics and assess the 1-year outcomes of hospitalized (HHF) and chronic (CHF) heart failure patients with chronic obstructive pulmonary disease (COPD) enrolled in a large European registry between May 2011 and April 2013.

METHODS AND RESULTS

Overall, 1334/6920 (19.3%) HHF patients and 1322/9409 (14.1%) CHF patients were diagnosed with COPD. In both groups, patients with COPD were older, more frequently men, had a worse clinical presentation and a higher prevalence of co-morbidities. In HHF, the increase in the use of heart failure (HF) medications at hospital discharge was greater in non-COPD than in COPD for angiotensin-converting enzyme inhibitors (+13.7% vs. +7.2%), beta-blockers (+20.6% vs. +11.8%) and mineralocorticoid receptor antagonists (+20.9% vs. +17.3%), thus widening the gap in HF treatment already existing between the two groups at admission. In CHF patients, there was a similar increase in the use of these medications after enrollment visit in the two groups, leaving a significant difference of 8.2% for beta-blockers in favour of non-COPD patients (89.8% vs. 81.6%, P < 0.001). At 1-year follow-up, the hazard ratios for COPD in multivariable analysis confirmed its independent association with hospitalizations both in HHF [all-cause: 1.16 (1.04-1.29), for HF: 1.22 (1.05-1.42)] and CHF patients [all-cause: 1.26 (1.13-1.41), for HF: 1.37 (1.17-1.60)]. The association between COPD and all-cause mortality was not confirmed in both groups after adjustments.

CONCLUSIONS

COPD frequently coexists in HHF and CHF, worsens the clinical course of the disease, and significantly impacts its therapeutic management and prognosis. The matter should deserve greater attention from the cardiology community.

Rationales and choices for the treatment of patients with NYHA class II heart failure

Heart failure (HF) in the United States represents a significant burden for patients and a tremendous strain on the healthcare system. Patients receiving a diagnosis of HF can be placed into 1 of 4 New York Heart Association (NYHA) functional classifications; the greatest proportion of patients are in the NYHA class II category, which is defined as patients having a slight limitation of physical activity but who are comfortable at rest, and for whom ordinary physical activity results in symptoms of HF. Because the severity of NYHA class II HF may be perceived as mild or unalarming by this definition, the urgency to treat this type of HF may be overlooked. However, these patients are optimal candidates for active intervention because their HF is at a critical point on the disease progression continuum when untoward changes can be halted or reversed. This review discusses the physiological consequences of NYHA class II HF with reduced ejection fraction and describes recent clinical trials that have demonstrated a therapeutic benefit for patients in this population. In doing so, we hope to establish that patients with NYHA class II disease merit careful attention and to provide reassurance to the treating community that options are available for these patients.

Non-Mask-based Therapies for Central Sleep Apnea in Patients with Heart Failure

Central sleep apnea is common in heart failure and contributes to morbidity and mortality. Symptoms are often similar to those associated with heart failure and a high index of suspicion is needed. Testing is typically done in the sleep laboratory, but home testing equipment can distinguish between central and obstructive events. Treatments are limited. Mask-based therapies have been the primary treatment. Oxygen has some data but lacks long-term studies. Neurostimulation of the phrenic nerve is a new technology that has demonstrated improvement. Coordination of care between sleep specialists and cardiologists is important as the field of central sleep apnea continues to develop.

Digoxin-induced retinal degeneration depends on rhodopsin

Na,K-ATPases are energy consuming ion pumps that are required for maintaining ion homeostasis in most cells. In the retina, Na,K-ATPases are especially important to sustain the dark current in photoreceptor cells needed for rapid hyperpolarization of rods and cones in light. Cardiac glycosides like digoxin inhibit the activity of Na,K-ATPases by targeting their catalytic alpha subunits. This leads to a disturbed ion balance, which can affect cellular function and survival. Here we show that the treatment of wild-type mice with digoxin leads to severe retinal degeneration and loss of vision. Digoxin induced cell death specifically in photoreceptor cells with no or only minor effects in other retinal cell types. Photoreceptor-specific cytotoxicity depended on the presence of bleachable rhodopsin. Photoreceptors of Rpe65 knockouts, which have no measurable rhodopsin and photoreceptors of Rpe65^R91W mice that have <10% of the rhodopsin found in retinas of wild-type mice were not sensitive to digoxin treatment. Similarly, cones in the all-cone retina of Nrl knockout mice were also not affected. Digoxin induced expression of several genes involved in stress signaling and inflammation. It also activated proteins such as ERK1/2, AKT, STAT1, STAT3 and CASP1 during a period of up to 10 days after treatment. Activation of signaling genes and proteins, as well as the dependency on bleachable rhodopsin resembles mechanisms of light-induced photoreceptor degeneration. Digoxin-mediated photoreceptor cell death may thus be used as an inducible model system to study molecular mechanisms of retinal degeneration.

Effect of liraglutide, a glucagon-like peptide-1 analogue, on left ventricular function in stable chronic heart failure patients with and without diabetes (LIVE)-a multicentre, double-blind, randomised, placebo-controlled trial

AIMS

To determine the effect of the glucagon-like peptide-1 analogue liraglutide on left ventricular function in chronic heart failure patients with and without type 2 diabetes.

METHODS AND RESULTS

LIVE was an investigator-initiated, randomised, double-blinded, placebo-controlled multicentre trial. Patients (n = 241) with reduced left ventricular ejection fraction (LVEF ≤45%) were recruited (February 2012 to August 2015). Patients were clinically stable and on optimal heart failure treatment. Intervention was liraglutide 1.8 mg once daily or matching placebo for 24 weeks. The LVEF was similar at baseline in the liraglutide and the placebo group (33.7 ± 7.6% vs. 35.4 ± 9.4%). Change in LVEF did not differ between the liraglutide and the placebo group; mean difference (95% confidence interval) was -0.8% (-2.1, 0.5; P = 0.24). Heart rate increased with liraglutide [mean difference: 7 b.p.m. (5, 9), P < 0.0001]. Serious cardiac events were seen in 12 (10%) patients treated with liraglutide compared with 3 (3%) patients in the placebo group (P = 0.04).

CONCLUSION

Liraglutide did not affect left ventricular systolic function compared with placebo in stable chronic heart failure patients with and without diabetes. Treatment with liraglutide was associated with an increase in heart rate and more serious cardiac adverse events, and this raises some concern with respect to the use of liraglutide in patients with chronic heart failure and reduced left ventricular function. More data on the safety of liraglutide in different subgroups of heart failure patients are needed.

Heart rate and heart failure

PURPOSE OF REVIEW

Resting heart rate has long been thought to be a risk factor in cardiovascular disease and a prognostic factor in heart failure. β-Blockers were originally used in heart failure for their heart rate control abilities. However, they also have negative inotropic effects contributing to their overall benefit. The role of isolated heart rate modification is unclear in left ventricular systolic dysfunction.

RECENT FINDINGS

Two recent studies looked at the heart rate-lowering effects of the If, or funny current inhibitor ivabradine and its potential role in heart failure therapy. At the doses chosen for the studies, ivabradine is presumed to have only effects on heart rate with no other cardiotropic effects. Thus, the cardiovascular outcome benefits are presumed to be secondary to heart rate modification.

SUMMARY

The two recent trials showed both heart rate and cardiovascular events to be significantly lower in the ivabradine-treated group of patients with left ventricular systolic dysfunction and initial heart rate at least 70 beats/min. However, neither of these trials proved causality. Hence, the link between heart rate and improved cardiovascular outcomes still remains muddled.

Heart failure 2016: still more questions than answers

Heart failure has reached epidemic proportions given the ageing of populations and is associated with high mortality and re-hospitalization rates. This article reviews and summarizes recent advances in the diagnosis, assessment and treatment of the patients with heart failure. Data are discussed based also on the most recent guidelines indications. Open issues and unmet needs are highlighted.

SCCT guidelines for the performance and acquisition of coronary computed tomographic angiography: A report of the society of Cardiovascular Computed Tomography Guidelines Committee: Endorsed by the North American Society for Cardiovascular Imaging (NASCI)

In response to recent technological advancements in acquisition techniques as well as a growing body of evidence regarding the optimal performance of coronary computed tomography angiography (coronary CTA), the Society of Cardiovascular Computed Tomography Guidelines Committee has produced this update to its previously established 2009 "Guidelines for the Performance of Coronary CTA" (1). The purpose of this document is to provide standards meant to ensure reliable practice methods and quality outcomes based on the best available data in order to improve the diagnostic care of patients. Society of Cardiovascular Computed Tomography Guidelines for the Interpretation is published separately (2). The Society of Cardiovascular Computed Tomography Guidelines Committee ensures compliance with all existing standards for the declaration of conflict of interest by all authors and reviewers for the purpose ofclarity and transparency.

A model model: a commentary on DiFrancesco and Noble (1985) 'A model of cardiac electrical activity incorporating ionic pumps and concentration changes'

This paper summarizes the advances made by the DiFrancesco and Noble (DFN) model of cardiac cellular electrophysiology, which was published in Philosophical Transactions B in 1985. This model was developed at a time when the introduction of new techniques and provision of experimental data had resulted in an explosion of knowledge about the cellular and biophysical properties of the heart. It advanced the cardiac modelling field from a period when computer models considered only the voltage-dependent channels in the surface membrane. In particular, it included a consideration of changes of both intra- and extracellular ionic concentrations. In this paper, we summarize the most important contributions of the DiFrancesco and Noble paper. We also describe how computer modelling has developed subsequently with the extension from the single cell to the whole heart as well as its use in understanding disease and predicting the effects of pharmaceutical interventions. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.