Empagliflozin does not change cardiac index nor systemic vascular resistance but rapidly improves left ventricular filling pressure in patients with type 2 diabetes: a randomized controlled study

Efficacy of Sodium-Glucose 2 Transporter Inhibitors in Heart Failure With Preserved Ejection Fraction: A Narrative Review

Heart failure with preserved ejection fraction (HFpEF) is an increasingly prevalent condition. It occurs more commonly in older patient populations with multiple comorbidities, such as hypertension, diabetes, and obesity. However, managing HFpEF has been challenging due to its complex pathophysiology, and medications effective for heart failure with reduced ejection fraction (HFrEF) have not shown similar efficacy in HFpEF. Sodium-glucose 2 transporter (SGLT2) inhibitors were originally developed for the treatment of type 2 diabetes mellitus, yet several trials and papers have proved their significant role in HFpEF. Through a variety of mechanisms, including natriuresis, diuresis, and anti-inflammatory effects, to name a few, this class of drugs has shown promising results in HFpEF patients. The use of SGLT2 inhibitors in HFpEF has resulted in improvements in several aspects, including biomarkers, imaging, symptomatology, and mortality. Moreover, SGLT2 inhibitors have a favorable safety profile, which is especially significant given the high comorbidity burden in HFpEF patients. This feature is particularly notable given the type of patient being managed. Extensive research is still being undertaken for their use in HFpEF, given the positive results obtained thus far.

Empagliflozin and left atrial function in patients with type 2 diabetes mellitus and coronary artery disease: insight from the EMPA-HEART CardioLink-6 randomized clinical trial

BACKGROUND

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have demonstrated reduction in heart failure outcomes in patients with type 2 diabetes mellitus, although the exact mechanism of benefit remains unclear. Alteration in left atrial (LA) function due to chronic pressure or volume overload is a hallmark of heart failure.

OBJECTIVE

To evaluate the effect of the SGLT2 inhibitor empagliflozin on LA volume and function.

METHODS

90 patients with coronary artery disease and type 2 diabetes (T2DM) were randomized to empagliflozin (n = 44) or placebo (n = 46), and underwent cardiac magnetic resonance (CMR) imaging at baseline and after 6 months. The main outcome was change in LA volume; LA function, including active and passive components, was also measured by a blinded reader.

RESULTS

At baseline, there was no significant difference in LA volumes between the empagliflozin (indexed maximum LA volume 26.4 ± 8.4mL/m2, minimum LA volume 11.1 ± 5.7mL/m2) and placebo (indexed maximum LA volume 28.7 ± 8.2mL/m2, minimum LA volume 12.6 ± 5.0mL/m2) groups. After 6 months, changes in LA volumes did not differ with adjusted difference (empagliflozin minus placebo): 0.99 mL/m2 (95% CI: -1.7 to 3.7 mL/m2; p = 0.47) for indexed maximum LA volume, and 0.87 mL/m2 (95% CI: -0.9 to 2.6 mL/m2; p = 0.32) for indexed minimum LA volume. Changes in total LA emptying fraction were also similar, with between-group adjusted mean difference - 0.01 (95% CI: -0.05 to 0.03, p = 0.59).

CONCLUSION

SGLT2 inhibition with empagliflozin for 6 months did not have a significant impact on LA volume and function in patients with T2DM and coronary artery disease. (Effects of Empagliflozin on Cardiac Structure in Patients with Type 2 Diabetes [EMPA-HEART]; NCT02998970).

Effects of 6-month administration of tofogliflozin on cardiac function in elderly patients with heart failure with preserved ejection fraction: A retrospective study of a patient cohort

Patients with type 2 diabetes mellitus are frequently hospitalized for heart failure. The ratio of early diastolic mitral inflow velocity to early diastolic mitral annulus velocity (E/e'), measured by echocardiography, is a simple and convenient indicator of diastolic dysfunction. Various large clinical trials have reported that sodium glucose transporter-2 inhibitor therapy reduced cardiovascular events and hospitalizations in heart failure patients. We examined the effect of tofogliflozin on various physiological and cardiac function. A retrospective analysis was performed on elderly patients aged 65 years or older with type 2 diabetes mellitus attending Himi Municipal Hospital who were taking oral tofogliflozin 20 mg/day. Measurement of physiological and hormonal variables, blood sampling, and echocardiographic evaluations at 0, 1, 3, and 6 months were performed on those with ejection fraction (EF) of 40% or greater at the time of treatment. Statistical analysis was performed using t-tests and mixed-effects models, with brain natriuretic peptide less than or not less than 100 pg/mL, estimated glomerular filtration rate (eGFR) less than or not less than 50 mL/min/1.73 m2, and diuretics administered or not. Hypoglycemic effects were observed at 0, 1, 3, and 6 months. At each time point, EF was retained and E/e' was significantly reduced. On the other hand, most physiological parameters and laboratory results showed no clinical abnormalities. Mixed-effects models showed time-dependent reduction of E/e' in high/low brain natriuretic peptide, high/low eGFR, with or without diuretics between baseline and at 6 months. The interaction with time was significant in high/low eGFR. Tofogliflozin was shown to improve E/e', a measure of diastolic function, while maintaining EF, with hypoglycemic effects and no clinical side effects.

Systematic Review of Left Ventricular Remodeling in Response to Hypoglycemic Medications: Assessing Changes in End-Systolic and End-Diastolic Diameters

Hypoglycemic medications are widely used in managing diabetes mellitus, with emerging evidence suggesting their role in cardiac reverse remodeling. This systematic review aims to quantitatively synthesize data regarding the impact of these medications on left ventricular end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD), and to evaluate the clinical relevance of these changes in promoting favorable cardiac outcomes. We conducted a comprehensive search across PubMed, Scopus, and the Web of Science up to 22 April 2024, selecting studies based on inclusion criteria that focused on the impact of hypoglycemic medications on LVEDD and LVESD in patients with diabetes. Studies were selected through a rigorous process, adhering to PRISMA guidelines, and involving various designs including randomized controlled trials and observational studies. The main outcomes were changes in LVEDD and LVESD measured by validated cardiac imaging techniques. A total of ten studies met the inclusion criteria, involving a total of 1180 patients. Treatment durations ranged from 3 to 24 months. Significant improvements in cardiac dimensions were noted with some medications. For instance, Liraglutide treatment over three months significantly improved LVEF from 47.2% to 57.2% and reduced LVEDD and LVESD from 46.5 mm to 45.2 mm and 35.2 mm to 32.7 mm, respectively. In contrast, other medications like Sitagliptin showed minimal impact over 24 months. On average, hypoglycemic medications reduced LVEDD from 58.2 mm to 55.0 mm and LVESD from 48.3 mm to 44.3 mm, with a mean improvement in LVEF from 38.9% to 43.8%. Hypoglycemic medications contribute variably to cardiac reverse remodeling. Medications such as Liraglutide and Dapagliflozin demonstrate significant potential in improving cardiac dimensions and function, indicating their utility beyond glycemic control. This review highlights the need for tailored treatment approaches to maximize cardiac outcomes in patients with diabetes, suggesting a broader therapeutic role for these agents.

Effects of SGLT2 Inhibitors on Cardiac Mechanics in Hispanic and Black Diabetic Patients

Background: Clinical trials demonstrating improved cardiovascular outcomes with SGLT2 inhibitors have often had limited representation from Black and Hispanic populations. While the mechanisms of action are not well known, ethnicity- or gender-based receptor physiology may render SGLT2 inhibitors a better agent in certain populations over others. Methods: A medical records query yielded diabetic patients initiated on SGLT2 inhibitors between 2013 and 2020. Patients with coronary artery disease, cardiac arrhythmias, and heart failure were excluded. Transthoracic echocardiographic studies (TTE) before and after starting SGLT2 inhibitors were analyzed, and post-processing left ventricular global longitudinal strain (LV GLS) analysis was also performed on each echocardiographic study. Univariate outliers and patients with missing data were excluded. Results: Among 94 patients with TTE (mean age 60.7 years; 68% Hispanics, 22.3% Blacks; median follow up of 7 months), there were significant improvements in the mean LV GLS (-15.3 vs. -16.5; p = 0.01), LV mass (LVM) (198.4 ± 59.6 g vs. 187.05 ± 50.6 g; p = 0.04), and LV mass index (LVMI) (100.6 ± 26.6 g/m2 vs. 94.3 ± 25.4 g/m2; p = 0.03) before and after initiating SGLT2 inhibitors but no significant change in the ratio (MV E/E') of peak early diastolic mitral flow velocity (E) and spectral pulsed-wave Doppler-derived early diastolic velocity from the septal mitral annulus (E') (12.5 ± 5.7 vs. 12.7 ± 4.8; p = 0.38). Changes in HbA1c (r2 = 0.82; p = 0.026), LVM (r2 = 0.20; p = 0.04), and LVMI (r2 = 0.20; p = 0.04) were found to be independently associated with changes in values of LV GLS on follow-up echocardiograms, when compared to the pre-medication LV GLS number. Conclusion: Non-White diabetic patients receiving SGLT2 inhibitors against a backdrop of other cardioprotective medications demonstrate significant improvements in LV remodeling and LV GLS, driven in part by an improvement in glycemic control. Large, prospective studies are needed to explore the differences in the therapeutic actions of SGLT2 inhibitors among different populations.

Impact of sodium-glucose cotransporter-2 inhibitor use on peak VO2 in advanced heart failure patients

Introduction

Advanced heart failure (HF) is an epidemic that affects multiple organ systems with high morbidity and mortality rates despite optimal medical therapy (OMT) and remains the leading cause of hospitalizations in type 2 diabetes-related cardiovascular disease. The addition of sodium-glucose co-transporter inhibitors (SGLT2i) in treating these patients has seen improved mortality and hospital admission rates. As such, we felt it was important to investigate whether the use of SGLT2i improved functional capacity in patients with HF when compared to OMT by evaluating maximum oxygen consumption (peak VO2) using cardiopulmonary exercise testing (CPET).

Methods

We found 94 heart failure patients between August 2020 and August 2021 who underwent CPET before and after treatment at Mayo Clinic in Florida. 50 patients received OMT and 44 received OMT and SGLT2i therapy. CPET results before and after were compared for each group.

Results

The baseline ejection fraction was not significantly different between groups, with the OMT group at 38% and the SGLT2i group at 33%, p = 0.10. OMT patients were found to have a significantly lower hemoglobin A1c of 5.7 (5.4-6.1) compared to those with SGLT2i therapy of 6.4 (5.8-7.1), p = 0.01. The baseline peak VO2 was 17.3 ml/kg/min (13.3-21.6) in the OMT group and 17.3 ml/kg/min (14.4-18.9) in the SGLT2i group, p = 0.18, not significantly different. The interesting finding is that the follow-up peak VO2 at one year for the OMT group was 17 ml/kg/min (13.3-21.6), which was not significantly different from the SGLT2i group peak VO2 of 17 ml/kg/min (14.6-19.6), p = 0.19. Our study is the first to compare before and after peak VO2 values of the OMT+SGLT2i group to the patient's own baseline and we found no significant improvement.

Conclusion

Our single-center data shows no improvement in functional capacity after the addition of SGLT2i therapy to OMT in patients with advanced heart failure. Improved hospitalization and symptoms may be attributed to other numerous effects of SGLT2i such as volume management.

Effects of Heart Failure Therapies on Atrial Fibrillation: Biological and Clinical Perspectives

Heart failure (HF) and atrial fibrillation (AF) are prevalent cardiovascular diseases that contribute significantly to morbidity, mortality, hospitalisation, and healthcare costs. It is not uncommon for these conditions to coexist and have mutually reinforcing effects. A critical factor in the aetiology of these conditions is oxidative stress, driven by reactive oxygen species (ROS), which contributes to atrial remodelling and fibrosis. The recent introduction of new drugs for the treatment of heart failure has also had an impact on the management of atrial fibrillation due to their influence on oxidative stress. The objective of this review is to analyse the effects of these therapies, including their role in mitigating ROS, on the prevention and treatment of AF in HF patients.

Ventricular remodeling and hemodynamic changes in heart failure patients with non-ischemic dilated cardiomyopathy following dapagliflozin initiation

BACKGROUND

In heart failure with reduced ejection fraction (HFrEF), sodium-glucose co-transporter inhibitors (SGLT-2i) have persistently shown cardiovascular benefits through different trials. However, their impact on ventricular remodeling and cardiac hemodynamics has not been sufficiently studied. This study aimed to study how SGLT-2i initiation affects invasive hemodynamics and cardiac magnetic resonance imaging (CMR)-derived ventricular volumes, function, and fraction of the extracellular volume (ECV) in HFrEF patients with non-ischemic dilated cardiomyopathy (NIDCM).

RESULTS

In this study, 23 patients with HFrEF and a mean age of 42, including 82.6% males, all have NIDCM and underwent right heart catheterization and CMR at the initiation of dapagliflozin and at 6-month follow-up. The addition of dapagliflozin resulted in significant reductions in the following invasive hemodynamic parameters compared to baseline: left ventricular end-diastolic pressure (23.4 vs 19.7 mmHg, p = 0.003), mean pulmonary artery pressure (31.3 vs 27.7 mmHg, p = 0.03), and systemic vascular resistance (18 vs 15 Wood units, p = 0.047). Among the studied CMR-derived measurements, only the percentage of extracellular volume fraction was significantly less at follow-up (33.7 vs 32.16%, p = 0.001). Additionally, functional class showed significant improvement with a notable reduction of the NT-proBNP level and a considerable decrease in diuretic dose (median: 40 vs 80 mg, p = 0.01).

CONCLUSION

Adding dapagliflozin to patients with HFrEF due to NIDCM improved invasively measured hemodynamics and significantly reduced left ventricular extracellular volume fraction measured by CMR, with no significant change in ventricular volumes or ejection fraction.

Empagliflozin improves left ventricular ejection fraction and end systolic volume in patients with type 2 diabetes mellitus and coronary artery disease: a post-hoc analysis of EMPA-CARD trial

Background

Sodium glucose co-transporter2 (SGLT2) inhibitors have exhibited cardioprotective properties in diabetes patients. The aim of this study was to investigate the effect of Empagliflozin on changes in echocardiographic parameters.

Methods

This was a post hoc analysis of the EMPA-CARD trial which was a multicenter, triple-blind randomized controlled trial. Type 2 diabetes mellitus patients with concomitant history of coronary artery disease were randomized on a 1:1 ratio into two groups receiving either 10 mg/day Empagliflozin or placebo. Patients with a history of heart failure (NYHA class 3-4) and ejection fraction (EF) < 40% were excluded. Trans-thoracic echocardiography was performed at baseline and at 26 weeks of intervention.

Results

A total of 69 (Empagliflozin = 39 and placebo = 30) patients underwent echocardiography. Significant changes were observed for left ventricular ejection fraction [standard error (SE) = 0.76; beta (95% correlation interval (CrI)] = -5.558 (-7.25; -4.18) and left ventricular end-systolic volume (SE = 1.38; beta (95% CrI) = 3.915 (1.2; 0.66). Other echocardiographic parameters relating to right ventricular or atrial function did not change significantly.

Conclusion

Empagliflozin can have cardioprotective benefits in subjects without HF. Further studies are required to determine the effect of Empagliflozin in non-HF patients.

Trial registration

The original EMPA-CARD study has been registered in Iranian Registry of Clinical Trials. www.IRCT.ir, Identifier: IRCT20190412043247N2. Registration Date: 6/13/2020. Registration timing: prospective.

Chapter 2: Clinical and Mechanistic Potential of Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitors in Heart Failure with Preserved Ejection Fraction

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) have emerged as an important approach for the treatment of heart failure in patients with or without diabetes. Although the precise mechanisms underpinning their clinical impact remain incompletely resolved, mechanistic studies and insights from major clinical trials have demonstrated the impact of SGLT2 inhibitors on numerous cardio-renal-metabolic pathways of relevance to heart failure with preserved ejection fraction (HFpEF), which, in the contemporary era, constitutes approximately half of all patients with heart failure. Despite rates of morbidity and mortality that are commensurate with those of heart failure with reduced ejection fraction, disease-modifying therapies have comparatively been severely lacking. As such, HFpEF remains among the greatest unmet needs in cardiovascular medicine. Within the past decade, HFpEF has been established as a highly integrated disorder, involving not only the cardiovascular system, but also the lungs, kidneys, skeletal muscle, and adipose tissue. Given their multisystem impact, SGLT2i offer unique promise in addressing the complex pathophysiology of HFpEF, and in recent randomized controlled trials, were shown to significantly reduce heart failure events and cardiovascular death in patients with HFpEF. Herein, we discuss several proposed mechanisms of clinical benefit of SGLT2i in HFpEF.

The role of empagliflozin-induced metabolic changes for cardiac function in patients with type 2 diabetes. A randomized cross-over magnetic resonance imaging study with insulin as comparator

BACKGROUND

Metabolic effects of empagliflozin treatment include lowered glucose and insulin concentrations, elevated free fatty acids and ketone bodies and have been suggested to contribute to the cardiovascular benefits of empagliflozin treatment, possibly through an improved cardiac function. We aimed to evaluate the influence of these metabolic changes on cardiac function in patients with T2D.

METHODS

In a randomized cross-over design, the SGLT2 inhibitor empagliflozin (E) was compared with insulin (I) treatment titrated to the same level of glycemic control in 17 patients with type 2 diabetes, BMI of > 28 kg/m2, C-peptide > 500 pM. Treatments lasted 5 weeks and were preceded by 3-week washouts (WO). At the end of treatments and washouts, cardiac diastolic function was determined with magnetic resonance imaging from left ventricle early peak-filling rate and left atrial passive emptying fraction (primary and key secondary endpoints); systolic function from left ventricle ejection fraction (secondary endpoint). Coupling between cardiac function and fatty acid concentrations, was studied on a separate day with a second scan after reduction of plasma fatty acids with acipimox. Data are Mean ± standard error. Between treatment difference (ΔT: E-I) and treatments effects (ΔE: E-WO or ΔI: I -WO) were evaluated using Students' t-test or Wilcoxon signed rank test as appropriate.

RESULTS

Glucose concentrations were similar, fatty acids, ketone bodies and lipid oxidation increased while insulin concentrations decreased on empagliflozin compared with insulin treatment. Cardiac diastolic and systolic function were unchanged by either treatment. Acipimox decreased fatty acids with 35% at all visits, and this led to reduced cardiac diastolic (ΔT: -51 ± 22 ml/s (p < 0.05); ΔE: -33 ± 26 ml/s (ns); ΔI: 37 ± 26 (ns, p < 0.05 vs ΔE)) and systolic function (ΔT: -3 ± 1% (p < 0.05); ΔE: -3 ± 1% (p < 0.05): ΔI: 1 ± 2 (ns, ns vs ΔE)) under chronotropic stress during empagliflozin compared to insulin treatment.

CONCLUSIONS

Despite significant metabolic differences, cardiac function did not differ on empagliflozin compared with insulin treatment. Impaired cardiac function during acipimox treatment, could suggest greater cardiac reliance on lipid metabolism for proper function during empagliflozin treatment in patients with type 2 diabetes.

TRIAL REGISTRATION

EudraCT 2017-002101-35, August 2017.

Sodium-glucose cotransporter-2 inhibitors (SGLT2) in frail or older people with type 2 diabetes and heart failure: a systematic review and meta-analysis

OBJECTIVE

Sodium-glucose cotransporter-2 inhibitors (SGLT2Is) reduce cardio-metabolic and renal outcomes in patients with type 2 diabetes (T2D) but their efficacy and safety in older or frail individuals remains unclear.

METHODS

We searched PubMed, Scopus, Web of Science, Cochrane CENTRA and Google Scholar and selected randomised controlled trials and observational studies comparing SGLT2Is versus placebo/other glucose-lowering agent for people with frailty or older individuals (>65 years) with T2D and heart failure (HF). Extracted data on the change in HbA1c % and safety outcomes were pooled in a random-effects meta-analysis model.

RESULTS

We included data from 20 studies (22 reports; N = 77,083 patients). SGLT2Is did not significantly reduce HbA1c level (mean difference -0.13, 95%CI: -0.41 to 0.14). SGLT2Is were associated with a significant reduction in the risk of all-cause mortality (risk ratio (RR) 0.81, 95%CI: -0.69 to 0.95), cardiac death (RR 0.80, 95%CI: -0.94 to 0.69) and hospitalisation for heart failure (HHF) (RR 0.69, 95%CI: 0.59-0.81). However, SGLT2Is did not demonstrate significant effect in reducing in the risk of macrovascular events (acute coronary syndrome or cerebral vascular occlusion), renal progression/composite renal endpoint, acute kidney injury, worsening HF, atrial fibrillation or diabetic ketoacidosis.

CONCLUSIONS

In older or frail patients with T2D and HF, SGLT2Is are consistently linked with a decrease in total mortality and the overall burden of cardiovascular (CV) events, including HHF events and cardiac death, but not protective for macrovascular death or renal events. Adverse events were more difficult to quantify but the risk of diabetic ketoacidosis or acute kidney injury was not significantly increase.

Effects of canagliflozin on cardiac remodeling and hemodynamic parameters in patients with type 2 diabetes mellitus

Sodium-glucose cotransporter type 2 (SGLT2) inhibitors have demonstrated to reduce cardiovascular risk in patients with type 2 diabetes mellitus (T2DM) in large trials independent of glycemic control. The mechanisms of this cardioprotective property remain uncertain. Evidence suggests positive hemodynamic changes and favorable cardiac remodeling contributing to the clinical outcomes but results were conflicting. We aim to investigate the potential impact on hemodynamic parameters, cardiac structure and functions. This prospective observational study included T2DM patients receiving canagliflozin 100 mg per day in addition to their antidiabetic treatment. We analyzed hemodynamic parameters assessed by echocardiographic measurements and impedance cardiography (ICG) to evaluate systolic and diastolic functions from baseline to 24 weeks after treatment. A total of 47 patients (25 males and 22 females) averaging 64.6 ± 10.9 years had a significant reduction in HbA1c, body weight, and systolic blood pressure. Hematocrit increased significantly, while NT-proBNP remained unchanged. E/e', left atrium (LA) volume, and LA stiffness were reduced, while left ventricle (LV) global longitudinal strain (GLS) and LA strain rates increased at 24 weeks by conventional and speckle tracking echocardiography. LV mass and ejection fraction showed no differences. ICG suggested significant improvement in hemodynamic parameters with increased stroke volume index and cardiac output index and decreased systemic vascular resistance index at 12 and 24 weeks. Canagliflozin improved hemodynamic parameters and had a favorable impact on LA and LV reverse remodeling. These changes may explain the beneficial effect on cardiovascular outcomes in large clinical trials.

The impact of sodium-glucose Cotransporter-2 inhibitors on lipid profile: A meta-analysis of 28 randomized controlled trials

AIM

The present study aimed to evaluate the impact of sodium-glucose cotransporter-2 inhibitors (SGLT2is) on blood lipid profile.

METHODS

We searched the PubMed, Cochrane Library, Medline, and EMBASE databases from the inception to July 2023 for randomized controlled trials (RCTs) comparing SGLT2i with placebo regarding lipid profile changes. The "Meta" package of R software was applied for data synthesis.

RESULTS

A total of 28 RCTs were included and 5192 patients participated in the present study, including 2686 patients who received SGLT2is intervention and 2506 patients who were in the control group. SGLT2is significantly increased blood low density lipoprotein cholesterol (LDL-C) levels [mean difference (MD): 0.09 mmol/L, 95% confidence interval (CI) (0.03, 0.16), 95% prediction interval (PI) (-0.06, 0.24), P = 0.0046] and high density lipoprotein cholesterol (HDL-C) levels [MD: 0.08 mmol/L, 95% CI (0.06, 0.11), 95% PI (-0.00, 0.17), P < 0.0001]. However, we observed neutral effect of SGLT2is on total cholesterol (TC) [MD: 0.08 mmol/L, 95% CI (-0.08, 0.24), 95% PI (-0.24, 0.40), P = 0.3150] and triglyceride (TG) [MD: -0.03 mmol/L, 95% CI (-0.23, 0.16), 95% PI (-0.70, 0.63), P = 0.7382].

CONCLUSION

Our study determined that SGLT2is increase both LDL-C and HDL-C levels, but exerts not significant effect on TC and TG levels.

Changes in Cardiovascular and Renal Biomarkers Associated with SGLT2 Inhibitors Treatment in Patients with Type 2 Diabetes Mellitus

Type 2 diabetes mellitus is a major health problem worldwide with a steadily increasing prevalence reaching epidemic proportions. The major concern is the increased morbidity and mortality due to diabetic complications. Traditional but also nontraditional risk factors have been proposed to explain the pathogenesis of type 2 diabetes mellitus and its complications. Hyperglycemia has been considered an important risk factor, and the strict glycemic control can have a positive impact on microangiopathy but not macroangiopathy and its related morbidity and mortality. Thus, the therapeutic algorithm has shifted focus from a glucose-centered approach to a strategy that now emphasizes target-organ protection. Sodium-glucose transporter 2 inhibitors is an extremely important class of antidiabetic medications that, in addition to their glucose lowering effect, also exhibit cardio- and renoprotective effects. Various established and novel biomarkers have been described, reflecting kidney and cardiovascular function. In this review, we investigated the changes in established but also novel biomarkers of kidney, heart and vascular function associated with sodium-glucose transporter 2 inhibitors treatment in patients with type 2 diabetes mellitus.

Sizing SGLT2 Inhibitors Up: From a Molecular to a Morpho-Functional Point of View

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), or gliflozins, have recently been shown to reduce cardiovascular death and hospitalization in patients with heart failure, representing a revolutionary therapeutic tool. The purpose of this review is to explore their multifaceted mechanisms of actions, beyond their known glucose reduction power. The cardioprotective effects of gliflozins seem to be linked to the maintenance of cellular homeostasis and to an action on the main metabolic pathways. They improve the oxygen supply for cardiomyocytes with a considerable impact on both functional and morphological myocardial aspects. Moreover, multiple molecular actions of SGLT2i are being discovered, such as the reduction of both inflammation, oxidative stress and cellular apoptosis, all responsible for myocardial damage. Various studies showed controversial results concerning the role of SGLT2i in reverse cardiac remodeling and the lowering of natriuretic peptides, suggesting that their overall effect has yet to be fully understood. In addition to this, advanced imaging studies evaluating the effect on all four cardiac chambers are lacking. Further studies will be needed to better understand the real impact of their administration, their use in daily practice and how they can contribute to benefits in terms of reverse cardiac remodeling.

Left ventricular remodeling response to SGLT2 inhibitors in heart failure: an updated meta-analysis of randomized controlled studies

BACKGROUND

Randomized controlled trials (RCTs) reported contrasting results about reverse left ventricular remodeling (LVR) after sodium-glucose co-transporter-2 inhibitors (SGLT2i) therapy in patients with heart failure (HF).

METHODS AND RESULTS

We performed a metanalysis of RCTs of SGLT2i administration in HF outpatients published until June 2022 searching four electronic databases. The protocol has been published in PROSPERO. Primary LVR outcome was change in absolute LV end-diastolic (LVEDV) and end-systolic volume (LVESV) from baseline to study endpoint. Secondary outcomes included changes in LVEDV and LVESV indexed to body surface area, LV Mass index (LVMi), LV ejection fraction (LVEF), and N-terminal pro-B-type natriuretic peptide (NTproBNP). Mean differences (MDs) with 95% CIs were pooled. A total of 9 RCTs (1385 patients) were analyzed. All of them reported data on LVEF. Six trials reported data on LVESV and LVEDV (n = 951); LVMi was available in 640. SGLT2i treatment significantly reduced LVEDV [MD= -10.59 ml (-17.27; -3.91), P = 0.0019], LVESV [MD= -8.80 ml (-16.91; -0.694), P = 0.0334], and LVMI [MD= -5.34 gr/m2 (-9.76; -0.922), P = 0.0178], while LVEF significantly increased [MD = + 1.98% (0.67; 0.306), P = 0.0031]. By subgroup analysis, the beneficial effects of SGLT2i on LVEF did not differ by imaging method used, time to follow-up re-evaluation, or HF phenotype. Reduction in LV volumes tended to be greater in HF with reduced EF (HFrEF) than in those with preserved EF (HFpEF), while the opposite was observed for LVMi.

CONCLUSIONS

Treatment with SGLT2i significantly reversed cardiac volumes, improving LV systolic function and LV mass, particularly in HFrEF patients.

Expanded use of sodium-glucose cotransporter 2 inhibitors: Evidence beyond heart failure with reduced ejection fraction

Following the results observed in the DAPA-HF trial and subsequent FDA approval of dapagliflozin in patients living with heart failure with reduced ejection fraction (HFrEF), numerous trials quickly began to assess the effects of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in a wide range of cardiovascular (CV) conditions. Since the publication of those findings, multiple SGLT2i have demonstrated benefit in patients regardless of left ventricular ejection fraction (LVEF)-allowing the drug class to establish itself within the first line of guideline-directed medication therapy. Although the full mechanistic properties of SGLT2i in heart failure (HF) have yet to be fully understood, benefits in other disease states have continued to emerge over the past decade. This review summarizes the findings of 14 clinical trials investigating the use of SGLT2i in various CV disease states, with a special focus on HF with preserved ejection fraction (HFpEF) and acute decompensated HF (ADHF). Additionally, studies assessing the CV-related mechanisms, cost-effectiveness, and exploratory effects of dual SGLT1/2 blockade are described. A review of select ongoing trials has also been incorporated to further characterize the research landscape with this medication class. The aim of this review is to serve as a comprehensive tool for healthcare providers to better understand how this class of diabetes medications established its place in the treatment of HF.

How Does It Work? Unraveling the Mysteries by Which Empagliflozin Helps Diabetic and Non-diabetic Patients With Heart Failure

In patients with heart failure, empagliflozin offers significant cardiovascular benefits. However, its exact mode of action is unknown. Understanding the way by which empagliflozin works in heart failure may uncover additional therapeutic targets or identify other classes of drugs that may be useful to clinicians and patients. This literature review aims to unravel the mysteries by which empagliflozin reduces cardiovascular death, cardiovascular events, and heart failure hospitalization in diabetic and non-diabetic patients. Three researchers conducted the data collection. We incorporated research that used human models, animal models, patients with diabetes, and patients without diabetes. Pathology, pathophysiology, metabolism, physiology, empagliflozin, heart failure, and cardiovascular were the search terms used to probe the mesh database on PubMed. This study showed that the mechanisms by which empagliflozin could lead to positive clinical outcomes in heart failure (HF) are as follows: down-regulation of the mammalian target of rapamycin complex 1 signaling (mTORC), decreasing sarcoplasmic reticulum calcium loss, increasing cytosolic calcium loss, inducing electrolyte-free osmotic diuresis, improving fuel efficiency, and protecting the endothelial glycocalyx. These findings were inconsistent, with no generally accepted hypotheses within the scientific community. Hence we conclude that further research is required to determine the function of Empagliflozin in heart failure and the degree to which the aforementioned mechanisms of action contribute to cardiac protection.

The effect of sodium-glucose cotransporter-2 inhibitors on cardiac structure remodeling and function: A meta-analysis of randomized controlled trials

BACKGROUND

It has been proven that sodium-glucose co-transporter 2 inhibitors (SGLT2is) improve the prognosis of patients with heart failure, independent of the presence of diabetes mellitus. Whether SGLT2 inhibitors affect cardiac structural remodeling and cardiac function is still uncertain.

METHODS

We included published randomized controlled trials (RCTs) to compare the effect of SGLT2is and control therapy in patients with or without heart failure. The meta-analysis was performed using Review Manager 5.3 software.

RESULTS

A total of 15 RCTs with a total of 1343 patients were selected for this meta-analysis, 663 of whom were on SGLT2is treatment and 680 of whom were in the control group. SGLT2is significantly improved heart rate (HR) [MD: -2.74, 95% CI (-4.71, -0.77), P = 0.006], left atrium volume index (LAVi) [MD: -1.99, 95% CI (-3.23,-0.75), P = 0.002], E/e' [MD: -1.47, 95% CI (-1.83,-1.10), P<0.00001], left ventricular mass index (LVMi) [MD: -2.38, 95% CI (-4.35, -0.40), P = 0.02], left ventricular end-systolic volume (LVESV) [MD: -6.50, 95% CI (-11.15,-1.84), P = 0.006], and left ventricular ejection fraction (LVEF) [MD: 1.78, 95% CI (0.56,3.01), P = 0.004] in the total population. Subgroup analysis indicated that compared with other SGLT2is, empagliflozin significantly decreased LVEDV, LVESV,LVMi, LAVi, E/e', and increased LVEF (P<0.05). In addition, the cardiac anti-remodeling effects of SGLT2 are particularly significant in patients with heart failure.

CONCLUSION

Our study showed that SGLT2is, particularly empagliflozin, significantly reverse cardiac remodeling in patients with heart failure. Empagliflozin may be a potentially promising agent to reverse cardiac remodeling in clinical practice.

Pathophysiological basis of the cardiological benefits of SGLT-2 inhibitors: a narrative review

In recent years, GLP-1 receptor agonists (GLP-1RA), and SGLT-2 inhibitors (SGLT-2i) have become available, which have become valuable additions to therapy for type 2 diabetes as they are associated with low risk for hypoglycemia and cardiovascular benefits. Indeed, SGLT-2i have emerged as a promising class of agents to treat heart failure (HF). By inhibiting SGLT-2, these agents lead to excretion of glucose in urine with subsequent lowering of plasma glucose, although it is becoming clear that the observed benefits in HF cannot be explained by glucose-lowering alone. In fact, multiple mechanisms have been proposed to explain the cardiovascular and renal benefits of SGLT-2i, including hemodynamic, anti-inflammatory, anti-fibrotic, antioxidant, and metabolic effects. Herein, we review the available evidence on the pathophysiology of the cardiological benefits of SGLT-2i. In diabetic heart disease, in both clinical and animal models, the effect of SGLT-2i have been shown to improve diastolic function, which is even more evident in HF with preserved ejection fraction. The probable pathogenic mechanisms likely involve damage from free radicals, apoptosis, and inflammation, and therefore fibrosis, many of which have been shown to be improved by SGLT-2i. While the effects on systolic function in models of diabetic heart disease and HF with preserved ejection fraction is limited and contrasting, it is a key element in patients with HF and reduced ejection fraction both with and without diabetes. The significant improvement in systolic function appears to lead to subsequent structural remodeling of the heart with a reduction in left ventricle volume and a consequent reduction in pulmonary pressure. While the effects on cardiac metabolism and inflammation appear to be consolidated, greater efforts are still warranted to further define the entity to which these mechanisms contribute to the cardiovascular benefits of SGLT-2i.

Association of Sodium-Glucose Cotransporter 2 Inhibitors with Osteomyelitis and Other Lower Limb Safety Outcomes in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Our aim was to evaluate osteomyelitis and other major lower limb safety outcomes (i.e., peripheral artery disease or PAD, ulcers, atraumatic fractures, amputations, symmetric polyneuropathy, and infections) in patients affected by type 2 diabetes mellitus (T2DM) and treated with sodium-glucose cotransporter 2 inhibitors (SGLT2-is). We thus performed a systematic review and meta-analysis of randomised controlled trials (RCTs) comparing SGLT2-is at approved doses for T2DM with a placebo or standard of care. MEDLINE, Embase, and Cochrane CENTRAL were searched through August 2022. Separate intention-to-treat analyses were implemented for each molecule to calculate Mantel-Haenszel risk ratios (RR_MH) with 95% confidence intervals (CIs) through a random-effects model. We processed data from 42 RCTs for a total of 29,491 and 23,052 patients, respectively assigned to SGLT2-i and comparator groups. SGLT2-is showed a pooled neutral effect on osteomyelitis, PAD, fractures, and symmetric polyneuropathy, whereas slightly deleterious sway on ulcers (RR_MH 1.39 [1.01-1.91]), amputations (RR_MH 1.27 [1.04-1.55]), and infections (RR_MH 1.20 [1.02-1.40]). In conclusion, SGLT2-is appear to not significantly interfere with the onset of osteomyelitis, PAD, lower limb fractures, or symmetric polyneuropathy, even though the number of these events proved consistently higher in the investigational groups; otherwise, local ulcers, amputations, and overall infections may be favoured by their employment. This study is registered with the Open Science Framework (OSF).

Sodium-Glucose Cotransporter 2 Inhibitors: A Scoping Review of the Positive Implications on Cardiovascular and Renal Health and Dynamics for Clinical Practice

Cardiorenal benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2is) have been demonstrated in patients with type 2 diabetes in multiple trials. We aim to provide a comprehensive review of the role of SGLT2i in cardiovascular disease. Reducing blood glucose to provide more effective vascular function, lowering the circulating volume, reducing cardiac stress, and preventing pathological cardiac re-modeling and function are the mechanisms implicated in the beneficial cardiovascular effects of SGLT2 inhibitors. Treatment with SGLT2i was associated with a decrease in cardiovascular and all-cause mortality, acute heart failure exacerbation hospitalization, and composite adverse renal outcomes. Improved symptoms, better functional status, and quality of life were also seen in heart failure with reduced ejection fraction (HFrEF), heart failure and mildly reduced ejection fraction (HFmrEF), and heart failure with preserved ejection fraction (HFpEF) patients. Recent trials have shown a notable therapeutic benefit of SGLT2is in acute heart failure and also suggest that SGLT2is have the potential to strengthen recovery after acute myocardial infarction (AMI) in percutaneous coronary Intervention (PCI) patients. The mechanism behind the cardio-metabolic and renal-protective effects of SGLT2i is multifactorial. Adverse events may occur with their usage including increased risk of genital infections, diabetic ketoacidosis, and perhaps limited amputations; however, all of them are preventable. Overall, SGLT2i clearly has many beneficial effects, and the benefits of using SGLT2i by far outweigh the risks.

Effect of Dapagliflozin on Cardiac Function and Metabolic and Hormonal Responses to Exercise

OBJECTIVE

This work aimed to investigate the effect of the SGLT2 inhibitor, dapagliflozin (DAPA), on cardiac function and the metabolic and hormonal response to moderate exercise in people with type 2 diabetes.

METHODS

This was a double-blind, placebo-controlled crossover study with a 4-week washout period. Nine participants were randomly assigned to receive either 4 weeks of DAPA or 4 weeks of placebo. After each treatment, they underwent an exercise protocol with 2 consecutive 10-minute stages at a constant load corresponding to 40% and 70% maximal oxygen consumption (VO2max), coupled with hormonal and metabolic analysis. A blinded transthoracic echocardiogram was performed 3 days later.

RESULTS

During the exercise protocol, glucose and lactate were lower (P < .0001 and P < .05, respectively) and β-hydroxybutyrate (BOBH) and growth hormone (GH) were higher (P < .0005 and P = .01) following DAPA treatment compared to placebo. There was a trend for lower insulin with DAPA. Adrenalin, noradrenalin, and glucagon were not different. Following DAPA participants demonstrated an increased mean peak diastolic mitral annular velocity (e') in comparison to placebo (P = .03). The indexed left atrial volume and right ventricular e" were reduced following DAPA compared with placebo (P = .045 and P = .042, respectively). Arterial stiffness was not different between treatments (DAPA 9.35 ± 0.60 m/s; placebo 9.07 ± 0.72 m/s).

CONCLUSION

During exercise, GH may be more important than catecholamines in driving the shift from glucose to fatty acid metabolism by SGLT2 inhibitors. The 4-week crossover design showed changes in cardiac function were rapid in onset and reversible.

Effects of 26 weeks of treatment with empagliflozin versus glimepiride on the myocardial glucose metabolic rate in patients with type 2 diabetes: The randomized, open-label, crossover, active-comparator FIORE trial

AIM

To determine whether treatment with empagliflozin was able to affect the myocardial glucose metabolic rate, as assessed by cardiac dynamic 18 F-fluorodeoxyglucose-positron emission tomography (18 F-FDG-PET) combined with euglycaemic-hyperinsulinaemic clamp compared with glimepiride in patients with type 2 diabetes.

MATERIALS AND METHODS

To further investigate the cardioprotective mechanism of sodium-glucose co-transporter-2 inhibitors, we performed a 26-week, randomized, open-label, crossover, active-comparator study to determine the effects of empagliflozin 10 mg versus glimepiride 2 mg daily on the myocardial glucose metabolic rate assessed by cardiac dynamic 18 F-FDG-PET combined with euglycaemic-hyperinsulinaemic clamp in 23 patients with type 2 diabetes. We also measured cardiac geometry and myocardial mechano-energetic efficiency, as well as systolic and diastolic function by echocardiography.

RESULTS

Compared with glimepiride, treatment with empagliflozin resulted in a greater reduction in the myocardial glucose metabolic rate from baseline to 26 weeks (adjusted difference -6.07 [-8.59, -3.55] μmol/min/100 g; P < .0001). Moreover, compared with glimepiride, empagliflozin led to significant reductions in left atrial diameter, left ventricular end-systolic and end-diastolic volumes, N-terminal pro b-type natriuretic peptide levels, blood pressure, heart rate, stroke work, and myocardial oxygen consumption estimated by the rate pressure product, and increases in ejection fraction, myocardial mechano-energetic efficiency, red blood cells, and haematocrit and haemoglobin levels.

CONCLUSIONS

The present study provides evidence that empagliflozin treatment in subjects with type 2 diabetes without coronary artery disease leads to a significant reduction in the myocardial glucose metabolic rate.

A New Chapter in the Treatment of Patients with Heart Failure. The Role of Sodium-Glucose Co-transporter Type 2 Inhibitors

Heart failure (HF) remains one of the major social and medical public health problems worldwide. Despite new advances in the treatment of patients with HF, the prognosis is still poor. According to the European Cardiology Society guidelines for the diagnosis and treatment of acute and chronic heart failure (CHF) 2021, a new class of drugs related to hypoglycemic has been confirmed to be effective in influencing the survival of patients with heart failure with low ejection fraction (HFpEF), regardless of the presence of disorders of carbohydrate metabolism. We are talking about inhibitors of the sodium-glucose co-transporter type 2 (iSGLT-2) or gliflozins. The article presents the results of the latest large clinical trials on the effective use of SGLT-2 in patients with HF, not only with low, but also with intact ejection fraction (HFpEF), for which there is no evidence base at the present stage. The review article presents the results of experimental studies that explored the potential mechanisms of action of gliflozins with an emphasis on new ones that are of fundamental importance for patients with heart failure, and also describes controversial and little-studied issues. Currently, there is no therapy that improves outcomes in patients with acute heart failure. The article presents the results of small analyzes of the use of iSGLT-2 in this category of patients, which are the basis for the hypothesis of their potentially effective and safe use in the case of acute decompensation of CHF, however, the role of gliflozins in this category of patients requires further in-depth study.

Comparison of Serum Ketone Levels and Cardiometabolic Efficacy of Dapagliflozin versus Sitagliptin among Insulin-Treated Chinese Patients with Type 2 Diabetes Mellitus

BACKGROUND

Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients.

METHODS

This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography.

RESULTS

Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e', an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037).

CONCLUSION

Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.

SGLT-2 inhibition by empagliflozin has no effect on experimental arterial thrombosis in a murine model of low-grade inflammation

AIMS

Low-grade inflammation couples dysmetabolic states to insulin resistance and atherosclerotic cardiovascular (CV) disease (ASCVD). Selective sodium-glucose co-transporter 2 (SGLT-2) inhibition by empagliflozin improves clinical outcomes in patients with ASCVD independently of its glucose lowering effects. Yet, its mechanism of action remains largely undetermined. Here, we aimed to test whether empagliflozin affects arterial thrombus formation in baseline (BSL) conditions or low-grade inflammatory states, a systemic milieu shared among patients with ASCVD.

METHODS AND RESULTS

Sixteen-week-old C57BL/6 mice were randomly assigned to acute administration of empagliflozin (25 mg/kg body weight) or vehicle, of which a subgroup was pre-treated biweekly over 4 weeks with super-low-dose lipopolysaccharide (LPS; 5 ng/kg body weight), before carotid thrombosis was induced by photochemical injury. The between-group difference in Doppler-flow probe detected time-to-occlusion remained within the predefined equivalence margin (Δ = |10.50|), irrespective of low-grade inflammation (95% confidence interval, -9.82 to 8.85 and -9.20 to 9.69), while glucose dropped by 1.64 and 4.84 mmoL/L, respectively. Ex vivo platelet aggregometry suggested similar activation status, corroborated by unchanged circulating platelet-factor 4 plasma levels. In concert, carotid PAI-1 expression and tissue factor (TF) activity remained unaltered upon SGLT-2 inhibition, and no difference in plasma d-dimer levels was detected, suggesting comparable coagulation cascade activation and fibrinolytic activity. In human aortic endothelial cells pre-treated with LPS, empagliflozin neither changed TF activity nor PAI-1 expression. Accordingly, among patients with established ASCVD or at high CV risk randomized to a daily dose of 10 mg empagliflozin signatures of thrombotic (i.e. TF) and fibrinolytic activity (i.e. PAI-1) remained unchanged, while plasma glucose declined significantly during 3 months of follow-up.

CONCLUSION

SGLT-2 inhibition by empagliflozin does not impact experimental arterial thrombus formation, neither under BSL conditions nor during sustained low-grade inflammation, and has no impact on proxies of thrombotic/fibrinolytic activity in patients with ASCVD. The beneficial pleiotropic effects of empagliflozin are likely independent of pathways mediating arterial thrombosis.

Investigating the roles of hyperglycaemia, hyperinsulinaemia and elevated free fatty acids in cardiac function in patients with type 2 diabetes via treatment with insulin compared with empagliflozin: protocol for the HyperCarD2 randomised, crossover trial

INTRODUCTION

Type 2 diabetes (T2D) is characterised by elevated plasma glucose, free fatty acid (FFA) and insulin concentrations, and this metabolic profile is linked to diabetic cardiomyopathy, a diastolic dysfunction at first and increased cardiovascular disease (CVD) risk. Shifting cardiac metabolism towards glucose utilisation has been suggested to improve cardiovascular function and CVD risk, but insulin treatment increases overall glucose oxidation and lowers lipid oxidation, without reducing CVD risk, whereas SGLT2 inhibitors (SGLT2i) increase FFA, ketone body concentrations and lipid oxidation, while decreasing insulin concentrations and CVD risk. The aim of the present study is to elucidate the importance of different metabolic profiles obtained during treatment with a SGLT2i versus insulin for myocardial function in patients with T2D.

METHODS AND ANALYSES

Randomised, crossover study, where 20 patients with T2D and body mass index>28 kg/m² receive 25 mg empagliflozin daily or NPH insulin two times per day first for 5 weeks followed by a 3-week washout before crossing over to the remaining treatment. Insulin treatment is titrated to achieve similar glycaemic control as with empagliflozin. In those randomised to insulin first, glycaemia during an initial empagliflozin run-in period prior to randomisation serves as target glucose. Metabolic and cardiac evaluation is performed before and at the end of each treatment period.The primary endpoint is change (treatment-washout) in left ventricular peak filling rate, as assessed by cardiac MRI with and without acute lowering of plasma FFAs with acipimox. Secondary and explorative endpoints are changes in left atrial passive emptying fraction, left ventricular ejection fraction, central blood volume and metabolic parameters.

ETHICS AND DISSEMINATION

This study is approved by the Danish Medicines Agency (ref. nr.: 2017061587), the Danish Data Protection Agency (ref. nr.: AHH-2017-093) and the Capital Region Ethics Committee (ref. nr.: H-17018846). The trial will be conducted in accordance with ICH-GCP guidelines and the Declaration of Helsinki and all participants will provide oral and written informed consent. Our results, regardless of outcome, will be published in relevant scientific journals and we also will seek to disseminate results through presentations at scientific meetings.

TRIAL REGISTRATION NUMBER

EudraCT: 2017-002101.

New antidiabetic therapy and HFpEF: light at the end of tunnel?

New antidiabetic therapy that includes sodium-glucose co-transporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor (GLP-1R) agonists, and dipeptidyl peptidase 4 (DPP-4) inhibitors showed significant benefit on cardiovascular outcomes in patients with and without type 2 diabetes mellitus, and this was particularly confirmed for SGLT2 inhibitors in subjects with heart failure (HF) with reduced ejection fraction (HFrEF). Their role on patients with HF with preserved ejection fraction (HFpEF) is still not elucidated, but encouraging results coming from the clinical studies indicate their beneficial role. The role of GLP-1R agonists and particularly DPP-4 inhibitors is less clear and debatable. Findings from the meta-analyses are sending positive message about the use of GLP-1R agonists in HFrEF therapy and revealed the improvement of left ventricular (LV) diastolic function in HFpEF. Nevertheless, the relevant medical societies still consider their effect as neutral or insufficiently investigated in HF patients. The impact of DPP-4 inhibitors in HF is the most controversial due to conflicting data that range from negative impact and increased risk of hospitalization due to HF, throughout neutral effect, to beneficial influence on LV diastolic dysfunction. However, this is a very heterogeneous group of medications and some professional societies made clear discrepancy between saxagliptin that might increase risk of HF hospitalization and those DPP-4 inhibitors that have no effect on hospitalization. The aim of this review is to summarize current clinical evidence about the effect of new antidiabetic medications on LV diastolic function and their potential benefits in HFpEF patients.

Effects of Sodium/Glucose Cotransporter 2 (SGLT2) Inhibitors on Cardiac Imaging Parameters: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Recent studies have shown that sodium/glucose cotransporter 2 (SGLT2) inhibitors might exert favourable changes on cardiac parameters as observed on cardiovascular imaging. We conducted a systematic review and meta-analysis to determine the effects of SGLT2 inhibitors on cardiac imaging parameters. Four electronic databases (PubMed, Embase, Cochrane, Scopus) were searched for studies in which the effects of SGLT2 inhibitors on cardiac imaging parameters were examined. Studies in which a population was administered SGLT2 inhibitors and analysed by echocardiography and/or cardiac magnetic resonance (CMR) imaging were included. Random-effects pair-wise meta-analysis models were utilized to summarize the studies. A total of 11 randomized controlled trials was included with a combined cohort of 910 patients. Comparing patients receiving SGLT2 inhibitors with subjects receiving placebo, the mean change in CMR-measured left ventricular mass (LVM) was -3.87 g (95% confidence interval [CI], -7.77 to 0.04), that in left ventricular end-systolic volume (LVESV) was -5.96 mL (95% CI, -10.52 to -1.41) for combined LVESV outcomes, that in left atrial volume index (LAVi) was -1.78 mL/m² (95% CI, -3.01 to -0.55) for combined LAVi outcomes, and that in echocardiography-measured E/e' was -0.73 (95% CI, -1.43 to -0.03). Between-group differences were not observed in LVM and LVESV after indexation. The only between-group difference that persisted was for LAVi. Treatment with SGLT2 inhibitors resulted in reduction in LAVi and E/e' on imaging, indicating they might have an effect on outcomes associated with LV diastolic function.

Putative protective effects of sodium-glucose cotransporter 2 inhibitors on atrial fibrillation through risk factor modulation and off-target actions: potential mechanisms and future directions

Atrial fibrillation, the most common cardiac arrhythmia, results in substantial morbidity and mortality related to its increased risks of stroke, heart failure, and impaired cognitive function. The incidence and prevalence of atrial fibrillation in the general population is rising, making atrial fibrillation treatment and management of its risk factors highly relevant clinical targets. One well-studied risk factor for the development of atrial fibrillation is diabetes mellitus. Inhibitors of sodium-glucose cotransporter 2 (SGLT2), common medications used to treat diabetes mellitus, have been observed to decrease the incidence of atrial fibrillation. This review discusses the SGLT2 and its role in glucose homeostasis, molecules inhibiting the transporter, possible physiological mechanisms responsible for the decreased incident atrial fibrillation in patients treated with SGLT2 inhibitors and proposes mechanistic studies to further our understanding of the biological processes involved.

Effects of SGLT2 inhibitors on cardiac structure and function

SGLT2 inhibitors reduce cardiovascular death or hospitalization for heart failure, regardless of the presence or absence of diabetes in patients at high cardiovascular risk and in those with heart failure and reduced ejection fraction (HFrEF). In patients with HF and preserved EF, empagliflozin also showed favorable effects mainly related to the reduction of hospitalization for heart failure. These favorable effects are beyond the reduction of glycemic levels and mainly related to beneficial hemodynamic and anti-inflammatory effects of these drugs and improved cardiac energy metabolism. In this review, we aimed to evaluate the effects of SGLT2 inhibitor on cardiac remodeling and function, which is still incompletely clear.

The impact of SGLT2 inhibition on imaging markers of cardiac function: A systematic review and meta-analysis

OBJECTIVES

The use of sodium-glucose cotransporter-2 inhibitors (SGLT2-Is) has resulted in significant benefits in patients with heart failure irrespective of left ventricular ejection fraction (LVEF) and the presence of diabetes mellitus. The aim of this systematic review and meta-analysis was to assess the impact of SGLT2-Is on cardiac function indices.

METHODS

We conducted a systematic literature search for studies assessing the changes in LVEF, global longitudinal strain (GLS), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular mass index (LVMi), left atrial volume index (LAVi), and E/e' following the initiation of an SGLT2-I.

RESULTS

A total of 32 studies with 2351 patients were included. SGLT2 inhibition resulted in a significant improvement of LVEF [MD 1.97 (95%CI 0.92, 3.02), p < .01, I²:84%] in patients with heart failure, an increase in GLS [MD 1.17 (95% CI 0.25, 2.10), p < .01], a decrease in LVESV [MD: -3.60 (95% CI -7.02, -0.18), p = .04, I²:9%] while the effect was neutral concerning LVEDV [MD: -3.10 (95% CI -6.76, 0.56), p = .40, I²:4%]. LVMi [MD: -3.99 (95% CI -7.16 to -0.82), p = .01, I²:65%], LAVi [MD: -1.77 (95% CI -2.97, -0.57), p < .01, I²:0%], and E/e' [MD: -1.39 (95% CI -2.04, -0.73), p < .01, I²:55%] were significantly reduced.

CONCLUSIONS

In this systematic review and meta-analysis, the use of SGLT2 inhibitors was associated with an improvement in markers of cardiac function, confirming the importance of SGLT2 inhibition towards the reversal of cardiac remodeling.

Beneficial Effect of Sodium-Glucose Co-transporter 2 Inhibitors on Left Ventricular Function

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors lowered the risk of cardiovascular events in patients with diabetes or heart failure (HF) with reduced ejection fraction, whether they directly promote cardiac function remains unclear. Therefore, we sought to determine whether SGLT2 inhibitors could improve left ventricular (LV) function in these patients.

METHODS

A literature search was conducted using MEDLINE, EMBASE, and Cochrane Library databases from their inception to July 9, 2021. Randomized clinical trials and cohort studies that reported LV function-related variables were included.

RESULTS

Thirteen studies comprising 1437 patients (830 SGLT2 inhibitor-treated and 607 non-SGLT2 inhibitor-treated patients) and representing 7 randomized controlled trials with 640 individuals and 6 cohort studies with 797 individuals were included in this meta-analysis. LV regression [LV mass (LVM)], LV ejection fractions (LVEF), LV volumes [LV end-diastolic volumes and systolic volumes (LVEDV and LVESV, respectively], and LV diastolic function [mitral inflow E velocity to tissue Doppler e' ratio, E/e' and left atrial volume index (LAVI)] were all significantly improved in patients treated with SGLT2 inhibitors (weighted mean differences, 95% CI, LVM: -6.319 g, -10.850 to -1.789; LVEF: 2.458%, 0.693 to 4.224; LVEDV: -9.134 mL, -15.808 to -2.460; LVESV: -8.440 mL, -15.093 to -1.787; LAVI: -2.791 mL/m2, -.554 to -1.027; E/e': -1.567, -2.440 to -0.698). Subgroup analysis further confirmed the improvement of LV function mainly in patients with HF or those receiving empagliflozin treatment.

CONCLUSIONS

Treatment with SGLT2 inhibitors can significantly improve LV function in patients with or without diabetes (especially those with HF or undergoing empagliflozin treatment).

Sodium Glucose Cotransporter-2 Inhibitors: Spotlight on Favorable Effects on Clinical Outcomes beyond Diabetes

Sodium glucose transporter type 2 (SGLT2) molecules are found in proximal tubules of the kidney, and perhaps in the brain or intestine, but rarely in any other tissue. However, their inhibitors, intended to improve diabetes compensation, have many more beneficial effects. They improve kidney and cardiovascular outcomes and decrease mortality. These benefits are not limited to diabetics but were also found in non-diabetic individuals. The pathophysiological pathways underlying the treatment success have been investigated in both clinical and experimental studies. There have been numerous excellent reviews, but these were mostly restricted to limited aspects of the knowledge. The aim of this review is to summarize the known experimental and clinical evidence of SGLT2 inhibitors' effects on individual organs (kidney, heart, liver, etc.), as well as the systemic changes that lead to an improvement in clinical outcomes.

Efficacy and safety of sodium-glucose cotransporter 2 inhibitors initiation in patients with acute heart failure, with and without type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

There is uncertainty and limited data regarding initiation of sodium-glucose cotransporter 2 (SGLT2) inhibitors among patients hospitalized with acute heart failure (AHF). This systematic review and meta-analysis aim to establish the efficacy and safety of SGLT2 inhibitors initiated in patients hospitalized for AHF.

METHODS

PubMed/Medline, Embase, and Cochrane library were searched using the following terms: ("sglt2" and "acute heart failure") and ("sglt2" and "worsening heart failure") from inception till November 15th, 2021 for randomized controlled trials (RCTs) comparing the efficacy and safety of initiating an SGLT2 inhibitor compared with placebo in patients with AHF. Major cardiovascular and diabetes scientific meetings in 2021 were also searched for relevant studies. Prespecified efficacy outcomes were all-cause mortality, rehospitalization for heart failure, and improvement in Kansas City Cardiomyopathy Questionnaire (KCCQ) scale score. Prespecified safety outcomes were acute kidney injury (AKI), hypotension, and hypoglycemia. Random effects odds ratio (OR) and mean difference with 95% confidence intervals (CIs) were calculated.

RESULTS

Three RCTs with a total of 1831 patients were included. Initiation of SGLT2 inhibitors in patients with AHF reduced the risk of rehospitalization for heart failure (OR 0.52; 95% CI [0.42, 0.65]) and improved Kansas City Cardiomyopathy Questionnaire scores (mean difference 4.12; 95% CI [0.1.89, 6.53]). There was no statistically significant effect for initiation of SGLT2 inhibitors in patients with AHF on all-cause mortality (OR 0.70; 95% CI [0.46, 1.08]). Initiation of SGLT2 inhibitors in patients with AHF did not increase the acute kidney injury (OR 0.76; 95% CI [0.50, 1.16]), hypotension (OR 1.17; 95% CI [0.80, 1.71]), or hypoglycemia (OR 1.51; 95% CI [0.86, 2.65]).

CONCLUSION

Initiation of SGLT2 inhibitors in patients hospitalized for AHF during hospitalization or early post-discharge (within 3 days) reduces the risk of rehospitalization for heart failure and improves patient-reported outcomes with no excess risk of adverse effects.

Effects of empagliflozin on markers of calcium and phosphate homeostasis in patients with type 2 diabetes – Data from a randomized, placebo-controlled study

Background and aim

Sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucose-lowering drugs that increase urinary glucose excretion have been shown to reduce CV events in patients with type 2 diabetes (T2D). Furthermore, several studies have demonstrated that treatment with SGLT2 inhibitors affect calcium and phosphate homeostasis, but the effect of empagliflozin on these biomarkers is hitherto not investigated in detail. Therefore, this analysis of the EMPA hemodynamics study examined effects of empagliflozin on calcium and phosphate homeostasis.

Methods

In this placebo-controlled, randomized, double-blind study patients with T2D were randomized to empagliflozin 10 mg (n = 20) or placebo (n = 22). Biomarkers of calcium and phosphate homeostasis were assessed before, and after 3 days and 3 months of treatment.

Results

After 3 days of treatment empagliflozin significantly increased serum levels of phosphate (baseline: 1.10 ± 0.21 mmol/L; day 3: 1.25 ± 0.23 mmol/L; p = 0.036), parathyroid hormone (PTH) (baseline: 57.40 ± 30.49 pg/mL; day 3: 70.23 ± 39.25 pg/mL; p = 0.025), fibroblast growth factor 23 (FGF23) (baseline: 77.92 ± 24.31 pg/mL; day 3: 109.18 ± 58.20 pg/mL; p = 0.001) and decreased 1,25-dihydroxyvitamin D (baseline: 35.01 ± 14.01 ng/L; day 3: 22.09 ± 10.02 mg/L; p < 0.001), while no difference of these parameters was recorded after 3 months of treatment. Empagliflozin had no significant effects on serum calcium and markers of bone resorption (collagen type 1 β-carboxy-telopeptide = β-CTX) or formation (osteocalcin) after 3 days and 3 months of treatment.

Conclusions

Empagliflozin treatment of patients with T2D transiently increases serum phosphate, PTH and FGF23, and decreases 1,25-dihydroxyvitamin D. This might reflect a temporal increase of sodium driven phosphate reabsorption in the proximal tubule of the kidney caused by increased sodium availability in response to SGLT2 inhibition.

•

Empagliflozin transiently increases serum phosphate.

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This might reflect an increase of Na⁺ driven phosphate reabsorption in the kidney.

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Empagliflozin had no effects on markers of bone resorption or formation.

Effects of sodium-glucose cotransporter-2 inhibitors on cardiac structural and electrical remodeling: from myocardial cytology to cardiodiabetology

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have changed the clinical landscape of diabetes mellitus (DM) therapy through their favourable effects on cardiovascular outcomes. Notably, the use of SGLT2i has been linked to cardiovascular benefits regardless of DM status, while their pleiotropic actions remain to be fully elucidated. What we do know is that SGLT2i exert beneficial effects even at the level of the myocardial cell, and that these are linked to an improvement in the energy substrate, resulting in less inflammation and fibrosis. SGLT2i ameliorate myocardial extracellular matrix remodeling, cardiomyocyte stiffness and concentric hypertrophy, achieving beneficial remodeling of the left ventricle with significant implications for the pathogenesis and outcome of heart failure. Most studies show a significant improvement in markers of diastolic dysfunction along with a reduction in left ventricular hypertrophy. In addition to these effects there is electrophysiological remodeling, which explains initial data suggesting that SGLT2i have an antiarrhythmic action against both atrial and ventricular arrhythmias. However, future studies need to clarify not only the exact mechanisms of this beneficial functional, structural, and electrophysiological cardiac remodeling, but also its magnitude, and to determine whether this is a class or a drug effect.

Effects of empagliflozin on erythropoiesis in patients with type 2 diabetes: Data from a randomized, placebo-controlled study

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been shown to significantly reduce hospitalization for heart failure (HHF) and cardiovascular (CV) mortality in various CV outcome trials in patients with and without type 2 diabetes mellitus (T2D). SGLT2 inhibition further increased haemoglobin and haematocrit levels by an as yet unknown mechanism, and this increase has been shown to be an independent predictor of the CV benefit of these agents, for example, in the EMPA-REG OUTCOME trial. The present analysis of the EMPA haemodynamic study examined the early and delayed effects of empagliflozin treatment on haemoglobin and haematocrit levels, in addition to measures of erythropoiesis and iron metabolism, to better understand the underlying mechanisms. In this prospective, placebo-controlled, double-blind, randomized, two-arm parallel, interventional and exploratory study, 44 patients with T2D were randomized into two groups and received empagliflozin 10 mg or placebo for a period of 3 months in addition to their concomitant medication. Blood and urine was collected at baseline, on Day 1, on Day 3 and after 3 months of treatment to investigate effects on haematological variables, erythropoietin concentrations and indices of iron stores. Baseline characteristics were comparable in the empagliflozin (n = 20) and placebo (n = 22) group. Empagliflozin led to a significant increase in urinary glucose excretion (baseline: 7.3 ± 22.7 g/24 h; Day 1: 48.4 ± 34.7 g/24 h; P < 0.001) as well as urinary volume (baseline: 1740 ± 601 mL/24 h; Day 1: 2112 ± 837 mL/24 h; P = 0.011) already after 1 day and throughout the 3-month study period, while haematocrit and haemoglobin were only increased after 3 months of treatment (haematocrit: baseline: 40.6% ± 4.6%; Month 3: 42.2% ±  4.8%, P < 0.001; haemoglobin: baseline: 136 ± 19 g/L; Month 3: 142 ± 25 g/L; P = 0.008). In addition, after 3 months, empagliflozin further increased red blood cell count (P < 0.001) and transferrin concentrations (P = 0.063) and there was a trend toward increased erythropoietin levels (P = 0.117), while ferritin (P = 0.017), total iron (P = 0.053) and transferrin saturation levels (P = 0.030) decreased. Interestingly, the increase in urinary glucose excretion significantly correlated with the induction of erythropoietin in empagliflozin-treated patients at the 3-month timepoint (Spearman rho 0.64; P = 0.008). Empagliflozin increased haemoglobin concentrations and haematocrit with a delayed time kinetic, which was most likely attributable to increased erythropoiesis with augmented iron utilization and not haemoconcentration. This might be attributable to reduced tubular glucose reabsorption in response to SGLT2 inhibition, possibly resulting in diminished cellular stress as a mechanism for increased renal erythropoietin secretion.

Effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors on left ventricular remodelling and longitudinal strain: a prospective observational study

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) lower cardiovascular events in type 2 diabetes mellitus (T2DM) patients, although the mechanisms underlying these benefits are not clearly understood. Our aim was to study the effects of SGLT2i on left ventricular remodelling and longitudinal strain.

METHODS

Between November 2019 and April 2020, we included 52 patients with T2DM ≥ 18 years old, with HbA1c between 6.5 and 10.0%, and estimated glomerular filtration ≥ 45 ml/min/1.73 m². Patients were classified into SGLT2i group and control group, according to prescribed treatment by their referring physician. Conventional and speckle tracking echocardiography were performed by blinded sonographers, at baseline and after 6 months of treatment.

RESULTS

Among the 52 included patients (44% females, mean age 66.8 ± 8.6 years, mean HbA1c was 7.40 ± 0.7%), 30 patients were prescribed SGLT2i and 22 patients were classified as control group. Mean change in indexed left ventricular mass (LVM) was - 0.85 ± 3.31 g/m² (p = 0.003) in the SGLT2i group, and + 2.34 ± 4.13 g/m² (p = 0.58) in the control group. Absolute value of Global Longitudinal Strain (GLS) increased by a mean of 1.29 ± 0.47 (p = 0.011) in the SGLT2i group, and 0.40 ± 0.62 (p = 0.34) in the control group. We did not find correlations between changes in LVM and GLS, and other variables like change in HbA1c.

CONCLUSIONS

Among patients with T2DM, SGLT2i were associated with a significant reduction in indexed LVM and a significant increment in longitudinal strain measured by speckle tracking echocardiography, which may explain in part the clinical benefits found in clinical trials.

SGLT2 Inhibitors and Their Mode of Action in Heart Failure-Has the Mystery Been Unravelled?

PURPOSE OF REVIEW

SGLT2 inhibitors (SGLT2i) are new drugs for patients with heart failure (HF) irrespective of diabetes. However, the mechanisms of SGLT2i in HF remain elusive. This article discusses the current clinical evidence for using SGLT2i in different types of heart failure and provides an overview about the possible underlying mechanisms.

RECENT FINDINGS

Clinical and basic data strongly support and extend the use of SGLT2i in HF. Improvement of conventional secondary risk factors is unlikely to explain the prognostic benefits of these drugs in HF. However, different multidirectional mechanisms of SGLT2i could improve HF status including volume regulation, cardiorenal mechanisms, metabolic effects, improved cardiac remodelling, direct effects on cardiac contractility and ion-homeostasis, reduction of inflammation and oxidative stress as well as an impact on autophagy and adipokines. Further translational studies are needed to determine the mechanisms of SGLT2i in HF. However, basic and clinical evidence encourage the use of SGLT2i in HFrEF and possibly HFpEF.

Cardioprotection by SGLT2 Inhibitors-Does It All Come Down to Na+?

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are emerging as a new treatment strategy for heart failure with reduced ejection fraction (HFrEF) and—depending on the wistfully awaited results of two clinical trials (DELIVER and EMPEROR-Preserved)—may be the first drug class to improve cardiovascular outcomes in patients suffering from heart failure with preserved ejection fraction (HFpEF). Proposed mechanisms of action of this class of drugs are diverse and include metabolic and hemodynamic effects as well as effects on inflammation, neurohumoral activation, and intracellular ion homeostasis. In this review we focus on the growing body of evidence for SGLT2i-mediated effects on cardiac intracellular Na⁺ as an upstream mechanism. Therefore, we will first give a short overview of physiological cardiomyocyte Na⁺ handling and its deterioration in heart failure. On this basis we discuss the salutary effects of SGLT2i on Na⁺ homeostasis by influencing NHE1 activity, late I_Na as well as CaMKII activity. Finally, we highlight the potential relevance of these effects for systolic and diastolic dysfunction as well as arrhythmogenesis.

Effects of empagliflozin on lipoprotein subfractions in patients with type 2 diabetes: data from a randomized, placebo-controlled study

BACKGROUND AND AIMS

Sodium-glucose cotransporter-2 inhibitors, glucose-lowering drugs that increase urinary glucose excretion, have been shown to reduce CV events in patients with type 2 diabetes (T2D), despite the fact that these agents increase blood levels of the proatherogenic low density lipoprotein cholesterol (LDL-C). It has been hypothesized that hemoconcentration due to osmotic diuresis, effects on calculated LDL particle size, or a modulation of lipoprotein subfractions may play a role in this context but to date the underlying mechanisms remain largely unexplored. Therefore, the present study examined effects of empagliflozin on LDL-C and lipoprotein subfractions including calculated LDL particle size and composition.

METHODS

In this placebo-controlled, randomized, double blind study, patients with T2D were randomized to empagliflozin 10 mg (n = 20) or placebo (n = 22). Composition of lipoprotein subfractions was assessed before and after 3 months of treatment. Lipoproteins were separated using a combined ultracentrifugation-precipitation method (β-quantification).

RESULTS

Empagliflozin increased LDL-C after 3 months of treatment (from baseline: 103 ± 36 mg/dL to 112 ± 47 mg/dL; p < 0.001) while no difference was recorded after day 1 or day 3 of treatment. The increase of LDL-C was paralleled by an increase of total cholesterol (baseline: 169 ± 41 mg/dL, 3 months: 185 ± 48 mg/dL; p = 0.001). Analyses of lipoprotein subfractions revealed LDL phospholipids and LDL apolipoprotein B to be increased by empagliflozin after 3 months of treatment while calculated LDL particle size was not affected. In addition empagliflozin increased free fatty acid concentrations.

CONCLUSIONS

Empagliflozin treatment of patients with T2D increased LDL-C and LDL apolipoprotein B levels but had no effect on calculated LDL particle size.