Comparison of Outcomes in Patients With Diabetes Mellitus Treated With Versus Without Insulin + Heart Failure With Preserved Left Ventricular Ejection Fraction (from the TOPCAT Study)

New Mechanisms to Prevent Heart Failure with Preserved Ejection Fraction Using Glucagon-like Peptide-1 Receptor Agonism (GLP-1 RA) in Metabolic Syndrome and in Type 2 Diabetes: A Review

This review examines the impact of obesity on the pathophysiology of heart failure with preserved ejection fraction (HFpEF) and focuses on novel mechanisms for HFpEF prevention using a glucagon-like peptide-1 receptor agonism (GLP-1 RA). Obesity can lead to HFpEF through various mechanisms, including low-grade systemic inflammation, adipocyte dysfunction, accumulation of visceral adipose tissue, and increased pericardial/epicardial adipose tissue (contributing to an increase in myocardial fat content and interstitial fibrosis). Glucagon-like peptide 1 (GLP-1) is an incretin hormone that is released from the enteroendocrine L-cells in the gut. GLP-1 reduces blood glucose levels by stimulating insulin synthesis, suppressing islet α-cell function, and promoting the proliferation and differentiation of β-cells. GLP-1 regulates gastric emptying and appetite, and GLP-1 RA is currently indicated for treating type 2 diabetes (T2D), obesity, and metabolic syndrome (MS). Recent evidence indicates that GLP-1 RA may play a significant role in preventing HFpEF in patients with obesity, MS, or obese T2D. This effect may be due to activating cardioprotective mechanisms (the endogenous counter-regulatory renin angiotensin system and the AMPK/mTOR pathway) and by inhibiting deleterious remodeling mechanisms (the PKA/RhoA/ROCK pathway, aldosterone levels, and microinflammation). However, there is still a need for further research to validate the impact of these mechanisms on humans.

Obesity and cardiovascular disease: mechanistic insights and management strategies. A joint position paper by the World Heart Federation and World Obesity Federation

The ongoing obesity epidemic represents a global public health crisis that contributes to poor health outcomes, reduced quality of life, and >2.8 million deaths each year. Obesity is relapsing, progressive, and heterogeneous. It is considered a chronic disease by the World Obesity Federation (WOF) and a chronic condition by the World Heart Federation (WHF). People living with overweight/obesity are at greater risk for cardiovascular (CV) morbidity and mortality. Increased adiposity (body fat), particularly visceral/abdominal fat, is linked to CV risk and CV disease (CVD) via multiple direct and indirect pathophysiological mechanisms. The development of CVD is driven, in part, by obesity-related metabolic, endocrinologic, immunologic, structural, humoral, haemodynamic, and functional alterations. The complex multifaceted nature of these mechanisms can be challenging to understand and address in clinical practice. People living with obesity and CVD often have concurrent chronic physical or psychological disorders (multimorbidity) requiring multidisciplinary care pathways and polypharmacy. Evidence indicates that intentional weight loss (particularly when substantial) lowers CVD risk among people with overweight/obesity. Long-term weight loss and maintenance require ongoing commitment from both the individual and those responsible for their care. This position paper, developed by the WOF and the WHF, aims to improve understanding of the direct and indirect links between overweight/obesity and CVD, the key controversies in this area and evidence relating to cardiometabolic outcomes with available weight management options. Finally, an action plan for clinicians provides recommendations to help in identifying and addressing the risks of obesity-related CVD (recognizing resource and support variances between countries).

Prognostic relevance of left atrial function and stiffness in heart failure with preserved ejection fraction patients with and without diabetes mellitus

Background

Although the left atrium (LA) plays a key role in the pathophysiology and disease progression of heart failure with preserved ejection fraction (HFpEF), the impact of type 2 diabetes mellitus (T2DM) on LA function and stiffness in HFpEF patients remains unclear. Furthermore, the prognostic value of different phases of LA function and stiffness is less well-established in HFpEF patients.

Methods

This study prospectively enrolled 164 HFpEF patients who were in sinus rhythm at the time of echocardiography, including 61 (37%) HFpEF patients with T2DM. LA reservoir, conduit, and pump function were assessed using two-dimensional volume indices and speckle tracking echocardiography. The LA stiffness was calculated as the ratio of early mitral inflow velocity-to-early annular tissue velocity (E/e’) and LA reservoir function. The primary end point was a combined outcome of heart failure hospitalization or death.

Results

Left atrium reservoir function [measured by peak LA strain (LAS-peak)] and LA pump function (measured by LAS-active) remained significantly lower in the HFpEF patients with T2DM compared with those without T2DM, even after adjustment for potential confounders. In addition, the LA stiffness of HFpEF patients with T2DM was higher than those without T2DM. After a median follow-up of 13.7 months, 46 patients (28.1%) reached the composite end point. LAS-peak (hazard ratios: 0.88; 95% confidence interval: 0.81–0.95; P = 0.001) was significantly associated with the risk of heart failure hospitalization or death after adjusting for demographic and clinical characteristics, LV global longitudinal strain, E/e’, and LA volume index. In contrast, other LA function and stiffness parameters did not independently predict the risk of adverse events. Kaplan-Meier analysis showed that HFpEF patients with T2DM and low LAS-peak (<27.2%) had a significantly increased risk of heart failure-related hospitalization or death (log-rank P < 0.001).

Conclusion

Left atrium reservoir and pump function are impaired, whereas LA stiffness is increased in HFpEF patients with T2DM compared with those without T2DM. LAS-peak is a powerful predictor of adverse clinical outcomes and may be crucial for risk stratification in HFpEF patients with and without T2DM.

The Diabetic Cardiorenal Nexus

The end-stage of the clinical combination of heart failure and kidney disease has become known as cardiorenal syndrome. Adverse consequences related to diabetes, hyperlipidemia, obesity, hypertension and renal impairment on cardiovascular function, morbidity and mortality are well known. Guidelines for the treatment of these risk factors have led to the improved prognosis of patients with coronary artery disease and reduced ejection fraction. Heart failure hospital admissions and readmission often occur, however, in the presence of metabolic, renal dysfunction and relatively preserved systolic function. In this domain, few advances have been described. Diabetes, kidney and cardiac dysfunction act synergistically to magnify healthcare costs. Current therapy relies on improving hemodynamic factors destructive to both the heart and kidney. We consider that additional hemodynamic solutions may be limited without the use of animal models focusing on the cardiomyocyte, nephron and extracellular matrices. We review herein potential common pathophysiologic targets for treatment to prevent and ameliorate this syndrome.

Effects of sacubitril/valsartan on glycemia in patients with diabetes and heart failure: the PARAGON-HF and PARADIGM-HF trials

BACKGROUND

Compared with enalapril, sacubitril/valsartan lowered HbA1c and reduced new insulin therapy in patients with heart failure with reduced ejection fraction (HFrEF) and diabetes in the PARADIGM-HF trial. We sought to assess the glycemic effects of sacubitril/valsartan in heart failure with preserved ejection fraction (HFpEF) and diabetes, and across the spectrum of left ventricular ejection fraction (LVEF) in heart failure and diabetes.

METHODS

We compared the effect of sacubitril/valsartan, relative to valsartan, on HbA1c, new insulin therapy and hypoglycemia in the randomized controlled trial PARAGON-HF, and performed pooled analyses of PARAGON-HF and PARADIGM-HF.

RESULTS

Among 2395 patients with HFpEF and diabetes in PARAGON-HF, sacubitril/valsartan compared with valsartan reduced HbA1c (baseline-adjusted between-group difference in HbA1c change at 48 weeks: - 0.24%, 95% CI - 0.33 to - 0.16%, P < 0.001). Numerically, new insulin treatment was initiated less often in the sacubitril/valsartan group than in the valsartan group, but the difference was not statistically significant (12.8% vs. 16.1%; HR: 0.80, 95% CI 0.62-1.02, P = 0.07). Hypoglycemia adverse event reports were low, but more frequent in those receiving sacubitril/valsartan than in the valsartan group (4.2% vs. 2.6%; HR: 1.64, 95% CI 1.05-2.56, P = 0.030). In a pooled analysis of PARAGON-HF and PARADIGM-HF, the effect of sacubitril/valsartan on change in HbA1c was not significantly modified by LVEF (Pinteraction = 0.56). Across the spectrum of LVEF, sacubitril/valsartan reduced new insulin therapy (HR: 0.75, 95% CI 0.63-0.89, P = 0.001), compared with enalapril or valsartan.

CONCLUSIONS

Sacubitril/valsartan reduced HbA1c and new insulin therapy in patients with heart failure and diabetes across the spectrum of LVEF but may be associated with a slightly higher risk for hypoglycemia. Trial registration ClinicalTrials.gov NCT01920711.

Impact of insulin therapy on outcomes of diabetic patients with heart failure: A systematic review and meta-analysis

OBJECTIVE

To compare clinical outcomes in diabetic patients with heart failure managed by insulin with those managed by non-insulin (oral hypoglycemic agents and/or lifestyle modification) based therapy.

METHODS

PubMed and Scopus databases were searched for studies conducted on diabetic patients with heart failure. Studies were to compare outcomes of patients managed by insulin versus non-insulin therapies.

RESULTS

15 studies were included. Compared to those who were managed using non-insulin therapy, insulin-treated patients had increased risk of all-cause mortality (RR 1.46, 95% CI: 1.14, 1.88) and cardiovascular specific mortality (RR 1.62, 95% CI: 1.33, 1.96). Those managed using insulin also had increased risk of hospitalization (RR 1.45, 95% CI: 1.09, 1.93) and readmission (RR 1.49, 95% CI: 1.32, 1.67). There was no additional risk for stroke (RR 1.07, 95% CI: 0.91, 1.27) or myocardial infarction (MI) (RR 1.10, 95% CI: 0.96, 1.27) between the two groups of patients.

CONCLUSIONS

Receipt of insulin among diabetic patients with heart failure was associated with an increased risk of mortality, hospitalization and readmission compared to management using oral hypoglycemic agents and/or lifestyle modification. Such patients should be closely monitored for any adverse events.

Diabetes Mellitus and Heart Failure With Preserved Ejection Fraction: Role of Obesity

Heart failure with preserved ejection fraction is a growing epidemic and accounts for half of all patients with heart failure. Increasing prevalence, morbidity, and clinical inertia have spurred a rethinking of the pathophysiology of heart failure with preserved ejection fraction. Unlike heart failure with reduced ejection fraction, heart failure with preserved ejection fraction has distinct clinical phenotypes. The obese-diabetic phenotype is the most often encountered phenotype in clinical practice and shares the greatest burden of morbidity and mortality. Left ventricular remodeling plays a major role in its pathophysiology. Understanding the interplay of obesity, diabetes mellitus, and inflammation in the pathophysiology of left ventricular remodeling may help in the discovery of new therapeutic targets to improve clinical outcomes in heart failure with preserved ejection fraction. Anti-diabetic agents like glucagon-like-peptide 1 analogs and sodium-glucose co-transporter 2 are promising therapeutic modalities for the obese-diabetic phenotype of heart failure with preserved ejection fraction and aggressive weight loss via lifestyle or bariatric surgery is still key to reverse adverse left ventricular remodeling. This review focuses on the obese-diabetic phenotype of heart failure with preserved ejection fraction highlighting the interaction between obesity, diabetes, and coronary microvascular dysfunction in the development and progression of left ventricular remodeling. Recent therapeutic advances are reviewed.

Associations of BMI with mortality in HFpEF patients with concomitant diabetes with insulin versus non-insulin treatment

BACKGROUND

Obesity confers paradoxical survival benefits in heart failure with preserved ejection fraction (HFpEF). The purpose of this study was to examine the impact of DM and insulin treatment status on the associations of body mass index (BMI) with the death risks in HFpEF patients.

METHODS

HFpEF patients from the TOPCAT trial were included. Cox regression model was constructed to assess the relationship of BMI with the risks of all-cause death and cardiovascular death. Restricted cubic splines were used to characterize the dose-response associations of BMI with risks of death.

RESULTS

Compared with normal weight, hazard ratios of all-cause death in overweight and class I obesity were 0.62 (0.45-0.85), 0.67 (0.47-0.94) in no DM HFpEF patients, and 0.48 (0.25-0.91), 0.41 (0.22-0.79) in non-insulin-treated DM patients. However, insulin treatment removed this beneficial effect. Consistent results were found when modeling for time-updated BMI. Cubic spline analyses suggested a linear trend of increased death risk with higher BMI in insulin-treated DM patients.

CONCLUSIONS

The "obesity paradox" was present in HFpEF patients without DM or with non-insulin-treated DM but absent in those with insulin-treated DM. Insulin treatment may be a crucial confounder of the obesity paradox in HFpEF patients.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov. Unique identifier: NCT00094302.

Prognostic risk factors in patients with refractory heart failure treated with continuous veno-venous hemofiltration

INTRODUCTION

Investigation of the prognostic factors in patients with refractory heart failure (HF) undergoing continuous veno-venous hemofiltration (CVVH).

METHODS

Clinical data of 146 patients with refractory HF between May 2018 and December 2020 were retrospectively analyzed and divided into survival and death groups according to the prognosis. Vital signs, inflammatory markers, and renal function parameters were compared before and after treatment.

RESULTS

Central venous pressure levels were lower, whereas serum levels of brain natriuretic peptide, oxygen saturation, and cardiac output were higher after treatment (P < 0.05). Heart rate, systolic and diastolic blood pressures, serum levels of C-reactive protein, interleukin-6, tumor necrosis factor-α, interleukin-8, blood urea nitrogen, creatinine, and 24-h urinary protein were lower after treatment (P < 0.05).

CONCLUSION

CVVH improved renal function and regulated blood pressure and vital signs in patients with refractory HF. Age, APACHE II score, disease duration, and hypotension were risk factors affecting the prognosis. This article is protected by copyright. All rights reserved.

Diabetes and prediabetes in patients with heart failure and preserved ejection fraction

Aim

There is an association between heart failure with preserved ejection fraction (HFpEF) and insulin resistance, but less is known about the diabetic continuum, and in particular about pre‐diabetes, in HFpEF. We examined characteristics and outcomes of participants with diabetes or pre‐diabetes in PARAGON‐HF.

Methods and results

Patients aged ≥50 years with left ventricular ejection fraction ≥45%, structural heart disease and elevated N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) were eligible. Patients were classified according to glycated haemoglobin (HbA1c): (i) normal HbA1c, <6.0%; (ii) pre‐diabetes, 6.0%–6.4%; (iii) diabetes, ≥6.5% or history of diabetes. The primary outcome was a composite of cardiovascular (CV) death and total heart failure hospitalizations (HFH). Of 4796 patients, 50% had diabetes and 18% had pre‐diabetes. Compared to patients with normal HbA1c, patients with pre‐diabetes and diabetes more often were obese, had a history of myocardial infarction and had lower Kansas City Cardiomyopathy Questionnaire scores, while patients with diabetes had more clinical evidence of congestion, but similar NT‐proBNP concentrations. The risks of the primary composite outcome (rate ratio [RR] 1.59, 95% confidence interval [CI] 1.35–1.88), total HFH (RR 1.67, 95% CI 1.39–2.02) and CV death (hazard ratio [HR] 1.35, 95% CI 1.07–1.71) were higher among patients with diabetes, compared to those with normal HbA1c. Patients with pre‐diabetes had a higher risk (which was intermediate between that of patients with diabetes and those with normal HbA1c) of the primary outcome (HR 1.27, 95% CI 1.00–1.60) and HFH (HR 1.35, 95% CI 1.03–1.77), but not of CV death (HR 1.02, 95% CI 0.75–1.40). Patients with diabetes treated with insulin had worse outcomes than those not, and those with ‘lean diabetes’ had similar mortality rates to those with a higher body mass index, but lower rates of HFH.

Conclusion

Pre‐diabetes is common in patients with HFpEF and is associated with worse clinical status and greater risk of HFH. Clinical Trial Registration: ClinicalTrials.gov Identifier NCT01920711.

Pharmacotherapy of diabetes mellitus in patients with heart failure - a nation-wide analysis of contemporary treatment

AIM

Retrospective national sub-analysis of antidiabetic pharmacotherapy in patients with diabetes mellitus (DM) and heart failure (HF) based on data reported to the National Register of Paid Health Services in the Czech Republic between 2012-2018.

METHODOLOGY AND RESULTS

In 2012, there were 75,022 patients with HF and DM (i.e. 42.5% of patients with HF), 6 years later 117,265 (i.e. 41.0% of HF patients in 2018). The most represented antidiabetic drug was metformin (45.6%). Of the insulins and analogues, glargine showed the largest positive trend (5.8% 2012; 14.8% 2018). Empagliflozin was the most prescribed SGLT-2 inhibitor (1.8% in 2018). A decrease in prescribing was observed for saxagliptin (0.5% 2012; 0.1% 2018) and for sulfonylurea derivates - gliclazide (13.0% 2012; 10.3% in 2018) and glimepiride (12.9% 2012; 9.0% 2018). Linagliptin was the most prescribed dipeptidyl peptidase inhibitor (0.7% 2012; 6.8% 2018).

CONCLUSION

In the Czech Republic, between 2012 and 2008, there was an increase in prevalence of patients with heart failure and concomitant diabetes mellitus, their proportion being similar. In correspondence with other registries, metformin was used mostly. A positive trend was observed in prescription of DDP-4 and SGLT-2 inhibitors, while there was a significant decrease in patients taking sulfonylureas.

Impact of insulin therapy on the mortality of acute heart failure patients with diabetes mellitus

BACKGROUND

Patients with diabetes mellitus (DM) have a higher prevalence of heart failure (HF) than those without it. Approximately 40 % of HF patients have DM and they tend to have poorer outcomes than those without DM. This study evaluated the impact of insulin therapy on mortality among acute HF patients.

METHODS

A total of 1740 patients from the Korean Acute Heart Failure registry with DM were included in this study. The risk of all-cause mortality according to insulin therapy was assessed using the Cox proportional hazard models with inverse probability of treatment weighting to balance the clinical characteristics (pretreatment covariates) between the groups.

RESULTS

DM patients had been treated with either oral hypoglycemic agents (OHAs) alone (n = 620), insulin alone (n = 682), or insulin combined with OHAs (n = 438). The insulin alone group was associated with an increased mortality risk compared with the OHA alone group (HR = 1.41, 95 % CI 1.21-1.66]). Insulin therapy combined with OHAs also showed an increased mortality risk (HR = 1.29, 95 % CI 1.14-1.46) compared with the OHA alone group. Insulin therapy was consistently associated with increased mortality risk, regardless of the left ventricular ejection fraction (LVEF) or HF etiology. A significant increase in mortality was observed in patients with good glycemic control (HbA1c < 7.0 %) receiving insulin, whereas there was no significant association in patients with poor glycemic control (HbA1c ≥ 7.0%).

CONCLUSIONS

Insulin therapy was found to be associated with increased mortality compared to OHAs. The insulin therapy was harmful especially in patients with low HbA1c levels which may suggest the necessity of specific management strategies and blood sugar targets when using insulin in patients with HF.

Impact of Insulin Treatment on the Effect of Eplerenone: Insights From the EMPHASIS-HF Trial

BACKGROUND

Patients with heart failure with reduced ejection fraction (HFrEF) and insulin-treated diabetes have a high risk of cardiovascular complications. Mineralocorticoid receptor antagonists may mitigate this risk. We aim to explore the effect of eplerenone on cardiovascular outcomes and all-cause mortality in HFrEF patients with diabetes, including those treated with insulin in the EMPHASIS-HF trial (Eplerenone in Patients with Systolic Heart Failure and Mild Symptoms).

METHODS

The primary outcome was the composite of heart failure hospitalization or cardiovascular death. Cox models with treatment-by-diabetes subgroup interaction terms were used.

RESULTS

The median follow-up was 21 (10-33) months. Of the 2737 patients included, 623 (23%) had non-insulin-treated diabetes, 236 (9%) had insulin-treated diabetes and 1878 did not have diabetes. Patients with insulin-treated diabetes were younger, more often women, with higher body mass index, waist circumference, more frequent ischemic heart failure cause, impaired kidney function, and longer diabetes duration. Compared with patients without diabetes, those with insulin-treated diabetes had a 2-fold higher risk of having a primary outcome event. The hazard ratio (95% CI) for the effect of eplerenone, compared with placebo, on the primary outcome was 0.31 (0.19-0.50) in insulin-treated diabetes, 0.69 (0.50-0.93) in non-insulin-treated diabetes, and 0.72 (0.58-0.88) in patients without diabetes; interaction P=0.007. The annualized number needed-to-treat-to-benefit with regards to the primary outcome was 3 (95% CI, 3-4) in patients with insulin-treated diabetes, 16 (13-19) in patients with diabetes not receiving insulin, and 26 (24-28) in patients without diabetes.

CONCLUSIONS

Patients with insulin-treated diabetes experienced a greater benefit from eplerenone than those with diabetes not treated with insulin and people without diabetes. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00232180.

Heart failure management; a perspective from diabetes care

People with type 2 diabetes (T2DM) are recognized as having a 2-4 times increased risk of heart failure (HF). Ambulatory diabetes care has long concentrated on the prevention of microvascular and arterial disease, and surveillance for manageable problems such as with the feet and retinae. Accordingly, management of heart failure has never been a specific focus, although the preventative management of cardiac and kidney disease through glucose-lowering, blood pressure (BP) control, and blood lipid control, have had a positive impact on its incidence. Indeed, the very complexity of routine diabetes care, and its enormous prevalence, has generally excluded the management of any of the advanced late complications, whether cardiac, arterial, retinal, renal, or neurodegenerative. Furthermore, advances in HF management itself, in diagnostics, medications, and technology, has carried it deeper into the remit of specialist cardiological care. More recently and in addition to medications already routinely used in diabetes care such as renin-angiotensin system (RAS) blockers, some glucose-lowering therapies such as sodium glucose transporter inhibitors 2 (SGLT-2 inhibitors), have been found to have very positive effects on hospitalization for HF, indeed even in people who do not have T2DM. Here, from the perspective of the diabetologist, we review the clinical scenario of ambulatory diabetes care, in regard of how HF prevention and management should fit in to clinical practice.

STZ-diabetic rat heart maintains developed tension amplitude by increasing sarcomere length and crossbridge density

New Findings

What is the central question of this study?

In the papillary muscle from type I diabetic rats, does diabetes‐associated altered ventricular function result from changes of acto‐myosin interactions and are these modifications attributable to a possible sarcomere rearrangement?

What is the main finding and its importance?

For the first time, we showed that type‐I diabetes altered sarcomeric ultrastructure, as seen by transmission electron microscopy, consistent with physiological parameters. The diabetic condition induced slower timing parameters, which is compatible with a diastolic dysfunction. At the sarcomeric level, augmented β‐myosin heavy chain content and increased sarcomere length and crossbridges' number preserve myocardial stroke and could concur to maintain the ejection fraction.

Abstract

We investigated whether diabetes‐associated altered ventricular function, in a type I diabetes animal model, results from a modification of acto‐myosin interactions, through the in vitro recording of left papillary muscle mechanical parameters and examination of sarcomere morphology by transmission electron microscopy (TEM). Experiments were performed on streptozotocin‐induced diabetic and age‐matched control female Wistar rats. Mechanical isometric and isotonic indexes and timing parameters were determined. Using Huxley's equations, we calculated mechanics, kinetics and energetics of myosin crossbridges. Sarcomere length and A‐band length were measured on TEM images. Type I and III collagen and β‐myosin heavy chain (MHC) expression were determined by immunoblotting. No variation in resting and developed tension or maximum extent of shortening was evident between groups, but diabetic rats showed lower maximum shortening velocity and prolonged timing parameters. Compared to controls, diabetics also displayed a higher number of crossbridges with lower unitary force. Moreover, no change in type I and III collagen was associated to diabetes, but pathological rats showed a two‐fold enhancement of β‐MHC content and longer sarcomeres and A‐band, detected by ultrastructural morphometry. Overall, these data address whether a preserved systolic function accompanied by an altered diastolic phase results from a recruitment of super‐relaxed myosin heads or the phosphorylation of the regulatory light chain site in myosin. Although the early signs of diabetic cardiomyopathy were well expressed, the striking finding of our study was that, in diabetics, sarcomere modification may be a possible compensatory mechanism that preserves systolic function.

How Diabetes and Heart Failure Modulate Each Other and Condition Management

Heart failure (HF) and diabetes mellitus (DM) confer considerable burden on the health care system. Although these often occur together, DM can increase risk of HF, whereas HF can accelerate complications of DM. HF is a clinical syndrome resulting from systolic or diastolic impairment caused by ischemic, nonischemic (eg, DM), or other etiologies. HF exists along a spectrum from stage A (ie, persons at risk of DM) to stage D (ie, refractory HF from end-stage DM cardiomyopathy [DMCM]). HF is further categorized by reduced, midrange, and preserved ejection fraction (EF). In type 2 DM, the most prevalent form of DM, several pathophysiological mechanisms (eg, insulin resistance and hyperglycemia) can contribute to myocardial damage, leading to DMCM. Management of HF and DM and patient outcomes are guided by EF and drug efficacy. In this review, we focus on the interplay between HF and DM on disease pathophysiology, management, and patient outcomes. Specifically, we highlight the role of novel antihyperglycemic (eg, sodium glucose cotransporter 2 inhibitors) and HF therapies (eg, renin-angiotensin-aldosterone system inhibitors) on HF outcomes in patients with DM and HF.

Effect of insulin on readmission for heart failure following a hospitalization for acute heart failure

Aims

Type 2 diabetes mellitus (T2DM) is common in patients with heart failure (HF) and is related with worse outcomes. Insulin treatment is associated with sodium and water retention, weight gain, and hypoglycaemia—all pathophysiological mechanisms related to HF decompensation. This study aimed to evaluate the association between insulin treatment and the risk of 1 year readmission for HF in patients discharged for acute HF.

Methods and results

We prospectively included 2895 consecutive patients discharged after an episode of acute HF in a single tertiary hospital. Multivariable Cox regression, adapted for competing events, was used to assess the association between insulin treatment and 1 year readmission for HF in patients discharged after acute HF. Participants' mean age was 73.4 ± 11.2 years, 50.8% were women, 44.7% had T2DM [including 527 (18.2%) on insulin therapy], and 52.7% had preserved ejection fraction. At 1 year follow‐up, 518 (17.9%) patients had died and 693 (23.9%) were readmitted for HF. The crude risk of readmission for HF was higher in patients on insulin, with no differences in 1 year mortality. After multivariable adjustment, patients on insulin were at significantly higher risk of 1 year readmission for HF than patients with diabetes who were not on insulin (hazard ratio 1.28; 95% confidence interval 1.04–1.59, P = 0.022) and patients without diabetes (hazard ratio 1.26; 95% confidence interval 1.02–1.55, P = 0.035).

Conclusion

Following acute HF, patients with T2DM on insulin therapy are at increased risk of readmission for HF. Further studies unravelling the mechanisms behind this association are warranted.

Do most patients with obesity or type 2 diabetes, and atrial fibrillation, also have undiagnosed heart failure? A critical conceptual framework for understanding mechanisms and improving diagnosis and treatment

Obesity and diabetes can lead to heart failure with preserved ejection fraction (HFpEF), potentially because they both cause expansion and inflammation of epicardial adipose tissue and thus lead to microvascular dysfunction and fibrosis of the underlying left ventricle. The same process also causes an atrial myopathy, which is clinically evident as atrial fibrillation (AF); thus, AF may be the first manifestation of HFpEF. Many patients with apparently isolated AF have latent HFpEF or subsequently develop HFpEF. Most patients with obesity or diabetes who have AF and exercise intolerance have increased left atrial pressures at rest or during exercise, even in the absence of diagnosed HFpEF. Among patients with AF, those who also have latent HFpEF have increased risk for systemic thromboembolism and death. The identification of HFpEF in patients with obesity or diabetes alters the risk-to-benefit relationship of commonly prescribed treatments. Bariatric surgery and statins can ameliorate AF and reduce the risk for HFpEF. Conversely, antihyperglycaemic drugs that promote adipogenesis or cause sodium retention (insulin and thiazolidinediones) may increase the risk for heart failure in patients with an underlying ventricular myopathy. Patients with obesity and diabetes who undergo catheter ablation for AF are at increased risk for AF recurrence and for post-ablation increases in pulmonary venous pressures and worsening heart failure, especially if HFpEF coexists. Therefore, AF may be the earliest indicator of HFpEF in patients with obesity or type 2 diabetes, and recognition of HFpEF alters the management of these patients.

Insulin treatment and clinical outcomes in patients with diabetes and heart failure with preserved ejection fraction

Aims

Insulin causes sodium retention and hypoglycaemia and its use is associated with worse outcomes in heart failure (HF) with reduced ejection fraction. We have investigated whether this is also the case in HF with preserved ejection fraction (HFpEF).

Methods and results

We examined the association between diabetes/diabetes treatments and the risk of the primary composite of cardiovascular death or HF hospitalization, as well as other outcomes in adjusted analyses in CHARM‐Preserved (left ventricular ejection fraction ≥ 45%), I‐Preserve and TOPCAT (Americas) pooled. Of 8466 patients, 2653 (31%) had diabetes, including 979 (37%) receiving insulin. Patients receiving insulin were younger, had a higher body mass index, prevalence of ischaemic aetiology, N‐terminal pro‐B‐type natriuretic peptide and use of diuretics, worse New York Heart Association class and signs and symptoms, and worse quality of life and renal function, compared to patients with diabetes not on insulin. Among the 1398 patients with echocardiographic data, insulin use was associated with higher left ventricular end‐diastolic pressure and more diastolic dysfunction than in other participants. The primary outcome occurred at a rate of 6.3 per 100 patient‐years in patients without diabetes, and 10.2 and 17.1 per 100 patient‐years in diabetes patients without and with insulin use, respectively [fully adjusted hazard ratio (aHR) insulin‐treated diabetes vs. other diabetes: 1.41, 95% confidence interval (CI) 1.23–1.63, P < 0.001]. The adjusted HR is 1.67 (95% CI 1.20–2.32, p = 0.002) for sudden death (insulin‐treated diabetes vs. other diabetes).

Conclusions

Insulin use is associated with poor outcomes in HFpEF. Although we cannot conclude a causal association, the safety of insulin and alternative glucose‐lowering treatments in HF needs to be evaluated in clinical trials.

Type 2 diabetes mellitus increases long-term mortality risk after isolated surgical aortic valve replacement

BACKGROUND

Diabetes mellitus (DM) adversely affects morbidity and mortality for major atherosclerosis-related cardiovascular diseases and is associated with increased risk for the development of aortic stenosis. Clinical data regarding the impact of DM on outcomes of patients undergoing aortic valve replacement (AVR) have revealed inconsistent results. The aim of the current study was to investigate and compare the impact of type 2 DM on short-, intermediate- and long-term mortality between DM and non-DM patients who undergo isolated AVR.

METHODS

We performed an observational study in a large tertiary medical center over a 14-year period (2004-2018), which included all patients who had undergone isolated AVR surgery for the first time. Of the 1053 study patients, 346 patients (33%) had type 2 DM (DM group) and were compared with non-DM (non-DM group) patients (67%). Short-term (in-hospital), intermediate (1- and 3-years), and late (5- and 10-years) mortality were evaluated. Mean follow-up of was 69 ± 43 months.

RESULTS

Short-term (in-hospital) mortality was similar between the DM compared with the non-DM group: 3.5% and 2.5% (p = 0.517). Intermediate-term mortality (1- and 3-year) was higher in the DM group compared with the non-DM group, but did not reach statistical significance: 8.1% vs. 5.7% (p = 0.169) and 12.1% vs. 8.3% (p = 0.064) respectively. Long-term (5- and 10-year) mortality was significantly higher in the DM group, compared to the non-DM group: 19.4% vs. 12.9% (p = 0.007) and 30.3% vs. 23.5% (p = 0.020) respectively. Among the 346 DM patients, 55 (16%) were treated with insulin and 291 (84%) with oral antiglycemic medication only. Overall in-hospital mortality among insulin-treated DM patients was 7.3% compared with 2.7% among non insulin-treated DM patients (p = 0.201). Long-term mortality was higher in the subgroup of insulin-treated DM patients compared with the subgroup of non-insulin treated DM patients with an overall mortality rate of 36.4% vs. 29.2% (p = 0.039). Furthermore, predictors for late mortality included DM (HR 1.39 CI 1.03-1.86, p = 0.031) and insulin treatment (HR 1.76 CI 1.05-2.94, p = 0.033), as demonstrated after adjustment for confounders by multivariable analysis.

CONCLUSIONS

Type 2 DM is an independent predictor for long-term mortality after isolated AVR surgery.