Heart Failure: Epidemiology, Pathophysiology, and Management of Heart Failure in Diabetes Mellitus

The Effect of Ivabradine on Hospitalization of Heart Failure Patients: A Retrospective Cohort Study

Background

Ivabradine is recommended in heart failure (HF) patients to reduce cardiovascular death and hospitalization due to worsening of HF symptoms.

Aims and Objectives

To study the effect of Ivabradine in addition to guideline-directed medical therapy (GDMT) in a group of HF patients with HR more than 70 bpm, HF with reduced ejection fraction (HFrEF) left ventricular ejection fraction (LVEF ≤ 40%), and New York Heart Association class II-IV.

Methods

The study was conducted at Heart Hospital, Hamad Medical Corporation, Qatar. HF patients with age > 18 years, LVEF ≤40%, on GDMT, and HR of ≥70 bpm were included. The study population was divided into two groups: ivabradine group and non-ivabradine group. The primary outcomes were risk, number and length of hospitalizations due to worsening HF, and cardiovascular mortality. The secondary outcome was all-cause mortality. Baseline characteristics were collected at enrollment. Study outcomes were compared in the two groups by applying Chi-square and Fisher's exact tests. Logistic regression model was applied to assess both hospitalizations and cardiovascular mortality.

Results

A total of 111 patients were studied, 37 (33.94%) ivabradine group and 74 (66.67%) non-ivabradine group. Risk of hospitalization was lower in Ivabradine group compared to non-Ivabradine group (odds ratio: 0.43, 95% confidence interval [CI]: 0.16-1.015, P = 0.094). Average length of hospitalization in ivabradine and non-ivabradine groups was 12.54 and 8.91 days, respectively (incidence rate ratio [IRR]: 1.63, 95% CI: 0.79-3.38, P = 0.187). Compared to non-ivabradine, ivabradine patients had lower number of hospitalizations (IRR: 1.13, 95% CI: 0.61-2.11, P = 0.694). Death rate in both ivabradine and non-ivabradine groups was 3.

Conclusions

Ivabradine along with GDMT reduces the risk of hospitalization due to worsening HF symptoms. Ivabradine had no significant effect on cardiovascular mortality and all-cause mortality. HFrEF non-Arabs patients have lower risk, number and length of hospitalization, and mortality compared to Arabs.

The DANish randomized, double-blind, placebo controlled trial in patients with chronic HEART failure (DANHEART): A 2 × 2 factorial trial of hydralazine-isosorbide dinitrate in patients with chronic heart failure (H-HeFT) and metformin in patients with chronic heart failure and diabetes or prediabetes (Met-HeFT)

OBJECTIVES

The DANHEART trial is a multicenter, randomized (1:1), parallel-group, double-blind, placebo-controlled study in chronic heart failure patients with reduced ejection fraction (HFrEF). This investigator driven study will include 1500 HFrEF patients and test in a 2 × 2 factorial design: 1) if hydralazine-isosorbide dinitrate reduces the incidence of death and hospitalization with worsening heart failure vs. placebo (H-HeFT) and 2) if metformin reduces the incidence of death, worsening heart failure, acute myocardial infarction, and stroke vs. placebo in patients with diabetes or prediabetes (Met-HeFT).

METHODS

Symptomatic, optimally treated HFrEF patients with LVEF ≤40% are randomized to active vs. placebo treatment. Patients can be randomized in either both H-HeFT and Met-HeFT or to only one of these study arms. In this event-driven study, it is anticipated that 1300 patients should be included in H-HeFT and 1100 in Met-HeFT and followed for an average of 4 years.

RESULTS

As of May 2020, 296 patients have been randomized at 20 centers in Denmark.

CONCLUSION

The H-HeFT and Met-HeFT studies will yield new knowledge about the potential benefit and safety of 2 commonly prescribed drugs with limited randomized data in patients with HFrEF.

Clinical Approach to Assessment and Amelioration of Atherosclerotic Vascular Disease in Diabetes

Atherosclerotic cardiovascular disease is increased on average 2–3-fold in people with diabetes as compared to their non-diabetic counterparts and is the major cause of the increased morbidity and mortality in this disease. There is however heterogeneity in cardiovascular risk between individuals based on demographic, cardiometabolic and clinical risk factors in the setting of hyperglycemia, insulin resistance and obesity that needs to be taken into consideration in planning preventive interventions. Randomized clinical trials of agents or procedures used for amelioration of augmented CVD risk in diabetes have been pivotal in providing evidenced-based treatments. Improvement in hyperglycemia in both type 1 and type 2 diabetes is considered to be central in the prevention of microvascular and macrovascular complications although selected antihyperglycemic agents have demonstrated beneficial as well as possible deleterious off-target effects. Lowering low density lipoprotein cholesterol, treating hypertension and stopping smoking each play important roles in preventing cardiovascular disease in diabetes as they do in the general population and low dose aspirin is overall beneficial in high risk individuals. Hypertriglyceridemia may represent another important marker for augmented cardiovascular risk in diabetes and newer agents targeting dyslipidemia appear promising. The fall in cardiovascular events over the past two decades offers hope that modern intervention strategies as well as novel approaches such as those targeting inflammation may contribute to a continued reduction of cardiovascular disease in people with diabetes.

Blood Pressure Variability and Risk of Heart Failure in ACCORD and the VADT

OBJECTIVE

Although blood pressure variability is increasingly appreciated as a risk factor for cardiovascular disease, its relationship with heart failure (HF) is less clear. We examined the relationship between blood pressure variability and risk of HF in two cohorts of type 2 diabetes participating in trials of glucose and/or other risk factor management.

RESEARCH DESIGN AND METHODS

Data were drawn from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial and the Veterans Affairs Diabetes Trial (VADT). Coefficient of variation (CV) and average real variability (ARV) were calculated for systolic (SBP) and diastolic blood pressure (DBP) along with maximum and cumulative mean SBP and DBP during both trials.

RESULTS

In ACCORD, CV and ARV of SBP and DBP were associated with increased risk of HF, even after adjusting for other risk factors and mean blood pressure (e.g., CV-SBP: hazard ratio [HR] 1.15, P = 0.01; CV-DBP: HR 1.18, P = 0.003). In the VADT, DBP variability was associated with increased risk of HF (ARV-DBP: HR 1.16, P = 0.001; CV-DBP: HR 1.09, P = 0.04). Further, in ACCORD, those with progressively lower baseline blood pressure demonstrated a stepwise increase in risk of HF with higher CV-SBP, ARV-SBP, and CV-DBP. Effects of blood pressure variability were related to dips, not elevations, in blood pressure.

CONCLUSIONS

Blood pressure variability is associated with HF risk in individuals with type 2 diabetes, possibly a consequence of periods of ischemia during diastole. These results may have implications for optimizing blood pressure treatment strategies in those with type 2 diabetes.

Heart rate increases in liraglutide treated chronic heart failure patients: association with clinical parameters and adverse events

Background. Liraglutide, a glucagon-like peptide-1 agonist, is used for treatment of type 2 diabetes and has beneficial cardiovascular properties. However, treatment increases heart rate (HR) and possibly the risk of cardiovascular events in chronic heart failure (CHF) patients. We investigated potential associations between HR changes and clinical, laboratory and echocardiographic parameters and clinical events in liraglutide treated CHF patients. Methods. This was a sub-study of the LIVE study. CHF patients (N = 241) with a left ventricular ejection fraction ≤45% were randomised to 1.8 mg liraglutide daily or placebo for 24 weeks. Electrocardiograms (N = 117) and readouts from cardiac implanted electronic devices (N = 20) were analysed for HR and arrhythmias. Results. In patients with sinus rhythm (SR), liraglutide increased HR by 8 ± 9 bpm (pulse measurements), 9 ± 9 bpm (ECG measurements) and 9 ± 6 bpm (device readouts) versus placebo (all p<.005). Increases in HR correlated with liraglutide dose (p=.01). HR remained unchanged in patients without SR. Serious cardiac adverse events were not associated with HR changes. Conclusions. During 6 months of treatment, HR increased substantially in CHF patients with SR treated with liraglutide but was not associated with adverse events. The long-term clinical significance of increased HR in liraglutide treated CHF patients needs to be determined.

Clinical efficacy, safety and tolerability of aliskiren monotherapy: a protocol for an umbrella review

INTRODUCTION

Aliskiren is a newly developed medicine. As one of the effective renin-angiotensin-aldosterone system inhibitors, its role in lowering blood pressure has been recognised. However, its safety and tolerability still remain controversial. The aim of the paper is to systematically summarise the published studies about the clinical efficacy and side effects of aliskiren monotherapy.

METHODS AND ANALYSIS

A comprehensive review of PubMed, Embase and Cochrane Library databases published from inception until June 2019 will be conducted. The selected articles are meta-analyses that integrated the randomised controlled studies, which evaluated efficacy, safety and tolerability of aliskiren monotherapy. Two people will select eligible articles and extract data independently. Any disputes will be resolved by discussion or the arbitration of a third person. The quality of reporting evidence will be assessed using the AMSTAR 2 tool. Study selection process will be presented using a flowchart. We will re-analyse each outcome with the random effect methods if necessary. If possible, we will also calculate 95% prediction intervals for each random effect estimate, by using Egger's test to evaluate if the reporting bias existed.

ETHICS AND DISSEMINATION

Ethical approval is not required for the study, as we only collected data from available published materials. This umbrella review will be also submitted to a peer-reviewed journal for publication after completion.

PROSPERO REGISTRATION NUMBER

CRD42019142141.

A Systematic Review on Synthetic Drugs and Phytopharmaceuticals Used to Manage Diabetes

BACKGROUND

Diabetes is a multifactorial disease and a major cause for many microvascular and macrovascular complications. The disease will ultimately lead to high rate mortality if it is not managed properly. Treatment of diabetes without any side effects has always remained a major challenge for health care practitioners.

INTRODUCTION

The current review discusses the various conventional drugs, herbal drugs, combination therapy and the use of nutraceuticals for the effective management of diabetes mellitus. The biotechnological aspects of various antidiabetic drugs are also discussed.

METHODS

Structured search of bibliographic databases for previously published peer-reviewed research papers was explored and data was sorted in terms of various approaches that are used for the treatment of diabetes.

RESULTS

More than 170 papers including both research and review articles, were included in this review in order to produce a comprehensive and easily understandable article. A series of herbal and synthetic drugs have been discussed along with their current status of treatment in terms of dose, mechanism of action and possible side effects. The article also focuses on combination therapies containing synthetic as well as herbal drugs to treat the disease. The role of pre and probiotics in the management of diabetes is also highlighted.

CONCLUSION

Oral antihyperglycemics which are used to treat diabetes can cause many adverse effects and if given in combination, can lead to drug-drug interactions. The combination of various phytochemicals with synthetic drugs can overcome the challenge faced by the synthetic drug treatment. Herbal and nutraceuticals therapy and the use of probiotics and prebiotics are a more holistic therapy due to their natural origin and traditional use.

Mechanisms of Protective Effects of SGLT2 Inhibitors in Cardiovascular Disease and Renal Dysfunction

Type 2 diabetes mellitus is one of the most common forms of the disease worldwide. Hyperglycemia and insulin resistance play key roles in type 2 diabetes mellitus. Renal glucose reabsorption is an essential feature in glycaemic control. Kidneys filter 160 g of glucose daily in healthy subjects under euglycaemic conditions. The expanding epidemic of diabetes leads to a prevalence of diabetes-related cardiovascular disorders, in particular, heart failure and renal dysfunction. Cellular glucose uptake is a fundamental process for homeostasis, growth, and metabolism. In humans, three families of glucose transporters have been identified, including the glucose facilitators GLUTs, the sodium-glucose cotransporter SGLTs, and the recently identified SWEETs. Structures of the major isoforms of all three families were studied. Sodium-glucose cotransporter (SGLT2) provides most of the capacity for renal glucose reabsorption in the early proximal tubule. A number of cardiovascular outcome trials in patients with type 2 diabetes have been studied with SGLT2 inhibitors reducing cardiovascular morbidity and mortality. The current review article summarises these aspects and discusses possible mechanisms with SGLT2 inhibitors in protecting heart failure and renal dysfunction in diabetic patients. Through glucosuria, SGLT2 inhibitors reduce body weight and body fat, and shift substrate utilisation from carbohydrates to lipids and, possibly, ketone bodies. These pleiotropic effects of SGLT2 inhibitors are likely to have contributed to the results of the EMPA-REG OUTCOME trial in which the SGLT2 inhibitor, empagliflozin, slowed down the progression of chronic kidney disease and reduced major adverse cardiovascular events in high-risk individuals with type 2 diabetes. This review discusses the role of SGLT2 in the physiology and pathophysiology of renal glucose reabsorption and outlines the unexpected logic of inhibiting SGLT2 in the diabetic kidney.

Glucose-lowering therapy and cardiovascular outcomes in patients with type 2 diabetes mellitus and acute coronary syndrome

Diabetes is a common comorbidity in patients hospitalized for an acute coronary syndrome event, and prevalence is increasing. Among patients hospitalized with acute myocardial infarction, diabetes can be an independent predictor of mortality and new cardiovascular events; both short- and long-term outcomes are worse for patients with diabetes relative to those without, and undiagnosed diabetes is associated with greater mortality. The impact of glycemic control on cardiovascular outcomes and the best approach to treat hyperglycemia upon hospital admission for acute coronary syndrome in patients with or without known diabetes remain open questions. This review assesses available evidence for hyperglycemia management at the time of admission for acute coronary syndrome and, thereafter, finds that (1) admission plasma glucose plays a role in predicting adverse events, especially in patients with unknown diabetes; (2) glycated haemoglobin is a likely predictor of events in patients with unknown diabetes; and (3) hypoglycemia at the time of acute myocardial infarction hospital admission is an important predictor for mortality in patients with and without diabetes. Whether glucose-targeted insulin and glucose infusion have advantages over glucose-insulin-potassium infusion remains controversial. Evidence for the effect of novel glucose-lowering agents used at the time of an acute cardiovascular event is limited and requires more dedicated studies.

Efficacy of ivabradine for heart failure: A protocol for a systematic review of randomized controlled trial

BACKGROUND

Previous clinical trials have reported that ivabradine can effectively treat heart failure (HF). However, no systematic review has explored its efficacy and safety for HF. This systematic review will aim to evaluate the efficacy and safety of ivabradine for the treatment of patients with HF.

METHODS

We will search the literature from the following electronic databases from inception to the January 31, 2019: Cochrane Central Register of Controlled Trials, EMBASE, MEDILINE, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, and Wanfang Data. All randomized controlled trials (RCTs) of ivabradine for HF will be fully considered for inclusion without any restrictions. Additionally, grey literature including clinical trial registries, dissertations, and reference lists of included studies, conference abstracts will also be searched. Two researchers will review these literatures, extract data, and assess risk of bias of included RCTs separately. Data will be pooled by either fixed-effects model or random-effects model, and meta-analysis will be conducted if it is appropriate.

RESULTS

The primary outcome is all-cause mortality. The secondary outcomes comprise of change in body weight, urine output, change in serum sodium, and all adverse events.

CONCLUSIONS

The results of this study will summary provide up-to-dated evidence for assessing the efficacy and safety of ivabradine for HF.

ETHICS AND DISSEMINATION

It is not necessary to acquire ethical approval for this systematic review, because no individual patient data will be used in this study. The results of this systematic review will be published through peer-reviewed journals.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019120814.

Heart failure hospitalization with SGLT-2 inhibitors: a systematic review and meta-analysis of randomized controlled and observational studies

INTRODUCTION

Heart failure (HF) in type 2 diabetes mellitus (T2DM) poses a significant increase in mortality. Until recently, anti-diabetic drugs have not been shown to reduce hospitalization due to heart failure (hHF). While thiazolidinedione class and saxagliptin has shown a significantly increased risk, sodium-glucose linked co-transporter 2 inhibitors (SGLT-2Is) have demonstrated a significant reduction in the risk of hHF. Areas covered: We systematically searched the database of PubMed, Embase, ClinicalTrials.gov, and International conference presentation up to 25 December 2018 and retrieved all the studies that were conducted for ≥24 weeks and explicitly reported hHF outcome. Subsequently, we conducted the meta-analysis to study the effect of SGLT-2Is on hHF outcome in randomized controlled trials (RCTs), observational studies, and both. Expert opinion: The meta-analysis of RCTs (N = 34,322), observational studies (N = 15,36,339), and both (N = 15,70,661) demonstrated a significant decrease in hHF (OR 0.70, 0.64, 0.66, respectively, all p = 0.000) with SGLT-2Is compared to placebo or other anti-diabetes drugs in T2DM. A significant benefit in hHF (OR 0.68, p = 0.000) is also observed in patients with established HF (N = 3891) in sub-group meta-analysis of RCTs. Ongoing dedicated HF trials will further enlighten the merits of SGLT-2Is in patients with established heart failure (preserved or reduced) with or without T2DM.

Revisiting the Diabetes-Heart Failure Connection

PURPOSE OF THE REVIEW

To summarize current clinical data investigating the link between diabetes and heart failure pathophysiology, the association of glucose control with heart failure, and the impact of current antihyperglycemic drugs on heart failure.

RECENT FINDINGS

Although heart failure is one of the most prevalent outcomes occurring in real life and cardiovascular outcome trials, insufficient attention was given to this condition in diabetes research over the last decades. With both beneficial and detrimental findings for heart failure hospitalization in the health authority-mandated outcome trials for new antihyperglycemic agents, research on heart failure and its interplay with diabetes mellitus gained momentum. Diabetes mellitus and heart failure are both prevalent and intertwined conditions. While currently available heart failure therapies have a similar degree of effectiveness in patients with and without diabetes, the choice of glucose-lowering agents can substantially affect heart failure-related outcome.

SGLT2 inhibitors and mechanisms of cardiovascular benefit: a state-of-the-art review

Sodium-glucose cotransporter (SGLT)2 inhibitors have been demonstrated to reduce cardiovascular events, particularly heart failure, in cardiovascular outcome trials. Here, we review the proposed mechanistic underpinnings of this benefit. Specifically, we focus on the role of SGLT2 inhibitors in optimising ventricular loading conditions through their effect on diuresis and natriuresis, in addition to reducing afterload and improving vascular structure and function. Further insights into the role of SGLT2 inhibition in myocardial metabolism and substrate utilisation are outlined. Finally, we discuss two emerging themes: how SGLT2 inhibitors may regulate Na⁺/H⁺ exchange at the level of the heart and kidney and how they may modulate adipokine production. The mechanistic discussion is placed in the context of completed and ongoing trials of SGLT2 inhibitors in the prevention and treatment of heart failure in individuals with and without diabetes.

Antihyperglycemic Therapies to Treat Patients With Heart Failure and Diabetes Mellitus

There is increasing recognition of the relationship between diabetes and heart failure (HF). Comorbid diabetes is associated with worse outcomes in patients with HF, and death from HF forms a large burden of mortality among patients with diabetes and atherosclerotic cardiovascular disease. However, there is evidence of harm relating to the risk of HF outcomes from several antihyperglycemic therapies. The absence of well-powered randomized controlled studies has resulted in significant treatment variations in the glycemic management in patients with coexisting diabetes and HF. However, there is emerging evidence from recent clinical trials suggesting that sodium-glucose-co-transporter-2 inhibitors may be used as a therapy to improve HF outcomes. In order to understand the current state of knowledge, we reviewed the evolving evidence of antihyperglycemic therapies and present strategies to optimize these therapies in patients with diabetes and HF. This analysis is based on discussions among scientists, clinical trialists, industry sponsors, and regulatory representatives who attended the 12th Global Cardiovascular Clinical Trialists Forum, Washington, DC, December 1 to 3, 2016.

L-Carnitine: An Antioxidant Remedy for the Survival of Cardiomyocytes under Hyperglycemic Condition

BACKGROUND

Metabolic alterations as hyperglycemia and inflammation induce myocardial molecular events enhancing oxidative stress and mitochondrial dysfunction. Those alterations are responsible for a progressive loss of cardiomyocytes, cardiac stem cells, and consequent cardiovascular complications. Currently, there are no effective pharmacological measures to protect the heart from these metabolic modifications, and the development of new therapeutic approaches, focused on improvement of the oxidative stress condition, is pivotal. The protective effects of levocarnitine (LC) in patients with ischemic heart disease are related to the attenuation of oxidative stress, but LC mechanisms have yet to be fully understood.

OBJECTIVE

The aim of this work was to investigate LC's role in oxidative stress condition, on ROS production and mitochondrial detoxifying function in H9c2 rat cardiomyocytes during hyperglycemia.

METHODS

H9c2 cells in the hyperglycemic state (25 mmol/L glucose) were exposed to 0.5 or 5 mM LC for 48 and 72 h: LC effects on signaling pathways involved in oxidative stress condition were studied by Western blot and immunofluorescence analysis. To evaluate ROS production, H9c2 cells were exposed to H₂O₂ after LC pretreatment.

RESULTS

Our in vitro study indicates how LC supplementation might protect cardiomyocytes from oxidative stress-related damage, preventing ROS formation and activating antioxidant signaling pathways in hyperglycemic conditions. In particular, LC promotes STAT3 activation and significantly increases the expression of antioxidant protein SOD2. Hyperglycemic cardiac cells are characterized by impairment in mitochondrial dysfunction and the CaMKII signal: LC promotes CaMKII expression and activation and enhancement of AMPK protein synthesis. Our results suggest that LC might ameliorate metabolic aspects of hyperglycemic cardiac cells. Finally, LC doses herein used did not modify H9c2 growth rate and viability.

CONCLUSIONS

Our novel study demonstrates that LC improves the microenvironment damaged by oxidative stress (induced by hyperglycemia), thus proposing this nutraceutical compound as an adjuvant in diabetic cardiac regenerative medicine.