Why do SGLT2 inhibitors reduce heart failure hospitalization? A differential volume regulation hypothesis

From Plan to Pivot: How Model-Informed Drug Development Shaped the Dose Strategy of the Zibotentan/Dapagliflozin ZENITH Trials

Getting the dose right is a key challenge in drug development; model-informed drug development (MIDD) provides powerful tools to shape dose strategies and inform decision making. In this tutorial, the case study of the ZENITH trials showcases how a set of clinical pharmacology and MIDD approaches informed an impactful dose strategy. The endothelin A receptor antagonist zibotentan, combined with the sodium-glucose co-transporter-2 inhibitor dapagliflozin, has yielded a robust and significant albuminuria reduction in the Phase IIb trial ZENITH-CKD and is being investigated for reduction of kidney function decline in a high-risk chronic kidney disease population in the Phase III trial ZENITH High Proteinuria. Endothelin antagonist treatment has, until now, been limited by the class effect fluid retention. ZENITH-CKD investigated a wide range of zibotentan doses based on pharmacokinetics in renal impairment, competitor-data exposure-response modeling, and clinical trial simulations. Recruitment delays reduced interim analysis data availability; here, supportive dose-response modeling recovered decision-making confidence. At trial completion, the low-dose arm enabled Phase III dose selection between Phase IIb doses. Dose-response modeling of efficacy and Kaplan-Meier analyses of tolerability identified a kidney-function-based low-dose strategy of 0.25 or 0.75 mg zibotentan (with 10 mg dapagliflozin) to balance benefit/risk in ZENITH High Proteinuria. The applied clinical pharmacology and MIDD principles enabled successful Phase IIb dose finding, rationalized and built confidence in the innovative Phase III dosing strategy and identified a potential therapeutic window for zibotentan/dapagliflozin, providing the opportunity for a significant improvement in the treatment of chronic kidney disease with high proteinuria.

Dapagliflozin Effects on Cardiac Deformation in Heart Failure and Secondary Clinical Outcome

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors were shown to reduce morbidity and mortality in patients with heart failure.

OBJECTIVES

This study aims to assess potential effects of dapagliflozin in nondiabetic patients with heart failure with reduced ejection fraction (HFrEF) and heart failure with mildly reduced ejection fraction (HFmrEF) on cardiac function assessed by speckle tracking echocardiography (STE).

METHODS

This randomized, prospective, single-center, open-label trial compared consecutive nondiabetic outpatients with HFrEF or HFmrEF receiving dapagliflozin with patients treated with optimal medical therapy (OMT) except sodium-glucose cotransporter type 2 inhibitors. Primary endpoint was the presence of a significant modification of left ventricular global longitudinal strain, diastolic function (as peak atrial longitudinal strain) and right ventricular function by STE from baseline to 6 months. Cardiovascular events and parameters of congestion were assessed as safety-exploratory endpoints.

RESULTS

Overall, 88 patients (38% HFmrEF) were enrolled and randomized to start dapagliflozin on top of OMT (n = 44) or to continue with OMT (n = 44). All STE values improved in the dapagliflozin group after 6 months, whereas there was a nonsignificant improvement in OMT group. Moreover, when comparing the modification of STE parameters at follow-up in patients with HFrEF and HFmrEF, only the main treatment effect resulted statistically significant in both groups (P < 0.0001), indicating a significant difference between dapagliflozin and OMT.

CONCLUSIONS

This study provided randomized data on the beneficial effect of dapagliflozin in nondiabetic patients with HFrEF and HFmrEF in terms of myocardial performance measured by the most sensitive echocardiographic technique, ie, STE. This suggests its usefulness for left ventricular reverse remodeling and better quality of life in patients with HFrEF and HFmrEF. (Effects of Dapagliflozin on cardiac deformation and clinical outcomes in heart failure with reduced and mildly reduced ejection fraction [DAPA ECHO trial]; EudraCT number: 2021-005394-66).

The Renoprotective Mechanisms of Sodium-Glucose Cotransporter-2 Inhibitors (SGLT2i)-A Narrative Review

Chronic kidney disease (CKD) is a noncommunicable condition that has become a major healthcare burden across the globe, often underdiagnosed and associated with low awareness. The main cause that leads to the development of renal impairment is diabetes mellitus and, in contrast to other chronic complications such as retinopathy or neuropathy, it has been suggested that intensive glycemic control is not sufficient in preventing the development of diabetic kidney disease. Nevertheless, a novel class of antidiabetic agents, the sodium-glucose cotransporter-2 inhibitors (SGLT2i), have shown multiple renoprotective properties that range from metabolic and hemodynamic to direct renal effects, with a major impact on reducing the risk of occurrence and progression of CKD. Thus, this review aims to summarize current knowledge regarding the renoprotective mechanisms of SGLT2i and to offer a new perspective on this innovative class of antihyperglycemic drugs with proven pleiotropic beneficial effects that, after decades of no significant progress in the prevention and in delaying the decline of renal function, start a new era in the management of patients with CKD.

Contemporary Use of Sodium Glucose Co-Transporter 2 Inhibitors in Hospitalized Heart Failure Patients: A "Real-World" Experience

Background/Objectives: The aim of this study was to examine the association between in-hospital initiation of sodium glucose co-transporter 2 inhibitors (SGLT2is) and outcomes in hospitalized heart failure (HHF) patients utilizing data from a Greek center. Methods: The present work was a single-center, retrospective, observational study of consecutive HF patients hospitalized in a tertiary center. The study endpoint was all-cause mortality or HF rehospitalization. Univariate and multivariate Cox proportional-hazard models were conducted to investigate the association between SGLT2i administration at discharge and the study endpoint. Results: Sample consisted of 171 patients, 55 of whom (32.2%) received SGLT2is at discharge. Overall, mean follow-up period was 6.1 months (SD = 4.8 months). Patients who received SGLT2is at discharge had a 43% lower probability of the study endpoint compared to those who did not receive SGLT2is at discharge (HR = 0.57; 95% CI: 0.36-0.91; p = 0.018). After adjusting for age, gender, smoking, hemoglobin (Hgb), use of SGLT2is at admission, use of Angiotensin-Converting Enzyme Inhibitors (ACEI-Is)/Angiotensin Receptor Blockers (ARBs) at discharge and Sacubitril/Valsartan at discharge, the aforementioned result remained significant (HR = 0.38; 95% CI: 0.19-0.73; p = 0.004). The 55 patients who received SGLT2is at discharge were propensity score matched with the 116 patients who did not receive SGLT2is at discharge. Receiving SGLT2is at discharge continued to be significantly associated with a lower probability of the study endpoint (HR= 0.43; 95% CI: 0.20-0.89; p = 0.024). Conclusions: Initiation of SGLT2is in HHF patients may be associated with better outcomes.

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.

Sodium-Glucose Cotransporter 2 Inhibitor Combined with Conventional Diuretics Ameliorate Body Fluid Retention without Excessive Plasma Volume Reduction

We previously reported that sodium-glucose cotransporter 2 (SGLT2) inhibitors exert sustained fluid homeostatic actions through compensatory increases in osmotic diuresis-induced vasopressin secretion and fluid intake. However, SGLT2 inhibitors alone do not produce durable amelioration of fluid retention. In this study, we examined the comparative effects of the SGLT2 inhibitor dapagliflozin (SGLT2i group, n = 53) and the combined use of dapagliflozin and conventional diuretics, including loop diuretics and/or thiazides (SGLT2i + diuretic group, n = 23), on serum copeptin, a stable, sensitive, and simple surrogate marker of vasopressin release and body fluid status. After six months of treatment, the change in copeptin was significantly lower in the SGLT2i + diuretic group than in the SGLT2i group (-1.4 ± 31.5% vs. 31.5 ± 56.3%, p = 0.0153). The change in the estimated plasma volume calculated using the Strauss formula was not significantly different between the two groups. Contrastingly, changes in interstitial fluid, extracellular water, intracellular water, and total body water were significantly lower in the SGLT2i + diuretic group than in the SGLT2i group. Changes in renin, aldosterone, and absolute epinephrine levels were not significantly different between the two groups. In conclusion, the combined use of the SGLT2 inhibitor dapagliflozin and conventional diuretics inhibited the increase in copeptin levels and remarkably ameliorated fluid retention without excessively reducing plasma volume and activating the renin-angiotensin-aldosterone and sympathetic nervous systems.

The Impact of SGLT2 Inhibitors on Cardiovascular Outcomes in Patients With Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To evaluate the role of sodium-glucose cotransporter-2 (SGLT2) inhibitors in patients with heart failure with preserved ejection fraction (HFpEF).

DATA SOURCES

A literature search of PubMed, the Cochrane Library, and Google Scholar databases (January 2015 to June 20, 2023) was performed with keywords: sodium-glucose co-transporter 2 inhibitors OR SGLT2 inhibitors OR bexagliflozin OR canagliflozin OR dapagliflozin OR empagliflozin OR ertugliflozin OR sotagliflozin AND heart failure OR heart failure with preserved ejection fraction, and terms related to CV outcomes including cardiovascular death, hospitalization, hospitalization for heart failure, mortality, death, and major adverse cardiovascular event (MACE).

STUDY SELECTION AND DATA EXTRACTION

The reference list from retrieved articles as well as relevant review articles was considered. Pivotal randomized controlled trials and meta-analyses with a primary or secondary end point of CV death or heart failure hospitalization were included. Studies conducted solely in a diabetic patient population were excluded.

DATA SYNTHESIS

Dapagliflozin and empagliflozin, in a broad population of heart failure patients including, HFrEF, HFmrEF, HFpEF, and without diabetes, have shown consistent improvement in the combined outcome of CV death and hospitalization for heart failure (HR 0.80, 95% CI 0.73-0.87) and in the reduction of heart failure hospitalizations (HR 0.74, 95% CI 0.67-0.83). In patients with HFpEF, cardiovascular mortality was not demonstrated (HR 0.88, 95% CI 0.77-1.00). Rates of adverse events were low.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Patients with HFpEF and NYHA class II-III with frequent symptoms or hospitalizations for heart failure derive the most benefit from SGLT2 inhibitors with an overall goal of a reduction in heart failure hospitalizations.

CONCLUSIONS

The treatment of HFpEF has made progress, but there is still work to be done. Now, SGLT2 inhibitor therapy can be used to further help with symptom control and reduce overall hospitalizations for heart failure.

Applications of SGLT2 inhibitors beyond glycaemic control

Sodium-glucose cotransporter 2 (SGLT2) inhibitors were initially developed for their glucose-lowering effects and have shown a modest glycaemic benefit in people with type 2 diabetes mellitus (T2DM). In the past decade, a series of large, robust clinical trials of these therapies have demonstrated striking beneficial effects for various care goals, transforming the chronic disease therapeutic landscape. Cardiovascular safety studies in people with T2DM demonstrated that SGLT2 inhibitors reduce cardiovascular death and hospitalization for heart failure. Subsequent trials in participants with heart failure with reduced or preserved left ventricular ejection fraction demonstrated that SGLT2 inhibitors have beneficial effects on heart failure outcomes. In dedicated kidney outcome studies, SGLT2 inhibitors reduced the incidence of kidney failure among participants with or without diabetes. Post hoc analyses have suggested a range of other benefits of these drugs in conditions as diverse as metabolic dysfunction-associated steatotic liver disease, kidney stone prevention and anaemia. SGLT2 inhibitors have a generally favourable adverse effect profile, although patient selection and medication counselling remain important. Concerted efforts are needed to better integrate these agents into routine care and support long-term medication adherence to close the gap between clinical trial outcomes and those achieved in the real world.

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

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

Water Conservation Overrides Osmotic Diuresis During SGLT2 Inhibition in Patients With Heart Failure

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors are believed to improve cardiac outcomes due to their osmotic diuretic potential.

OBJECTIVES

The goal of this study was to test the hypothesis that vasopressin-driven urine concentration overrides the osmotic diuretic effect of glucosuria induced by dapagliflozin treatment.

METHODS

DAPA-Shuttle1 (Hepato-renal Regulation of Water Conservation in Heart Failure Patients With SGLT-2 Inhibitor Treatment) was a single-center, double-blind, randomized, placebo-controlled trial, in which patients with chronic heart failure NYHA functional classes I/II and reduced ejection fraction were randomly assigned to receive dapagliflozin 10 mg daily or placebo (1:1) for 4 weeks. The primary endpoint was change from baseline in urine osmolyte concentration. Secondary endpoints included changes in copeptin levels and solute free water clearance.

RESULTS

Thirty-three randomized, sodium-glucose cotransporter 2 inhibitor-naïve participants completed the study, 29 of whom (placebo: n = 14; dapagliflozin: n = 15) provided accurate 24-hour urine collections (mean age 59 ± 14 years; left ventricular ejection fraction 31% ± 9%). Dapagliflozin treatment led to an isolated increase in urine glucose excretion by 3.3 mmol/kg/d (95% CI: 2.51-4.04; P < 0.0001) within 48 hours (early) which persisted after 4 weeks (late; 2.7 mmol/kg/d [95% CI: 1.98-3.51]; P < 0.0001). Dapagliflozin treatment increased serum copeptin early (5.5 pmol/L [95% CI: 0.45-10.5]; P < 0.05) and late (7.8 pmol/L [95% CI: 2.77-12.81]; P < 0.01), leading to proportional reductions in free water clearance (early: -9.1 mL/kg/d [95% CI: -14 to -4.12; P < 0.001]; late: -11.0 mL/kg/d [95% CI: -15.94 to -6.07; P < 0.0001]) and elevated urine concentrations (late: 134 mmol/L [95% CI: 39.28-229.12]; P < 0.01). Therefore, urine volume did not significantly increase with dapagliflozin (mean difference early: 2.8 mL/kg/d [95% CI: -1.97 to 7.48; P = 0.25]; mean difference late: 0.9 mL/kg/d [95% CI: -3.83 to 5.62]; P = 0.70).

CONCLUSIONS

Physiological-adaptive water conservation eliminated the expected osmotic diuretic potential of dapagliflozin and thereby prevented a glucose-driven increase in urine volume of approximately 10 mL/kg/d · 75 kg = 750 mL/kg/d. (Hepato-renal Regulation of Water Conservation in Heart Failure Patients With SGLT-2 Inhibitor Treatment [DAPA-Shuttle1]; NCT04080518).

Sodium-glucose linked transporter 2 inhibitors in liver cirrhosis: Beyond their antidiabetic use

Type 2 diabetes mellitus (T2DM) and liver cirrhosis are clinical entities that frequently coexist, but glucose-lowering medication options are limited in cirrhotic patients. Sodium-glucose linked transporter 2 (SGLT2) inhibitors are a class of glucose-lowering medication that act independently of insulin, by causing glycosuria in the proximal convoluted tubule. In this review, we aimed to briefly present the main data and to provide insight into the pathophysiology and potential usefulness of SGLT2 inhibitors in cirrhotic patients with or without T2DM. SGLT2 inhibitors have been proven useful as antidiabetic treatment in patients with metabolic liver disease, with most robust data from patients with metabolic dysfunction-associated steatotic liver disease (MASLD), where they also showed improvement in liver function parameters. Moreover, it has been suggested that SGLT2 inhibitors may have effects beyond their antidiabetic action. Accordingly, they have exhibited cardioprotective effects, expanding their indication in patients with heart failure without T2DM. Since decompensated liver cirrhosis and congestive heart failure share common pathophysiological features, namely renin-angiotensin-aldosterone axis and sympathetic nervous system activation as well as vasopressin secretion, SGLT2 inhibitors could also be beneficial in patients with decompensated cirrhosis, even in the absence of T2DM.

Severe Hypotension With Concomitant Sodium-Glucose Co-Transporter-2 Inhibitor and Angiotensin Receptor-Neprilysin Inhibitor Therapy in a Patient With Heart Failure Reduced Ejection Fraction: A Case Report

Background: Large cardiovascular outcomes trials in individuals with heart failure, with and without diabetes, have demonstrated a significant risk reduction in the composite outcome of cardiovascular death or hospitalizations for heart failure with SGLT2 inhibitor therapy. These positive outcomes have led to the recommendation that SGLT2 inhibitors serve as backbone therapy in patients with heart failure reduced ejection fraction (HFrEF). To date, there has not been enough participants in clinical trials on concomitant SGLT2 inhibitor and angiotensin receptor-neprilysin inhibitor therapy to evaluate the benefits and risks of combination therapy with these two agents outside of smaller subgroup analyses. Case Summary: This case describes a Black female with diabetes meeting her glycemic targets and concomitant stable NYHA FC II HFrEF on guideline-directed medical therapy (GDMT) with sacubitril/valsartan, spironolactone and metoprolol succinate who developed severe hypotension and dehydration requiring hospitalization after initiation of SGLT2 inhibitor therapy. Practice Implications: This case report raises the question of whether those with type 2 diabetes, and/or those on background angiotensin receptor-neprilysin inhibitor therapy, who are euvolemic or sensitive to diuretic therapy should be started on lower dose dapagliflozin and titrated to 10 mg daily based on response. It also raises awareness to the potential increased diuretic effect produced with concomitant use of sacubitril/valsartan and dapagliflozin. Caution and education to mitigate the risk for volume depletion should be provided to those patients who are euvolemic and initiated on a SGLT2 inhibitor, regardless of their background diuretic and GDMT. Conclusion: Future research should focus on the benefits and safety considerations and provide education on how to best initiate and adjust SGLT2 inhibitors in the setting of sacubitril/valsartan use in diverse heart failure patient populations.

Early Longitudinal Change in Heart Failure Health Status Following Initiation of Canagliflozin

BACKGROUND

Sodium glucose co-transporter 2 inhibitor (SGLT2i) therapy improves health status in heart failure (HF). There is insufficient description regarding the timing, rate, and extent of the health status changes in heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) after initiation of SGLT2is.

OBJECTIVES

The authors sought to model the association of canagliflozin treatment with rates of change in HF symptom status in HFpEF and HFrEF.

METHODS

Study participants with HFrEF and HFpEF were treated with either canagliflozin 100 mg or placebo for 12 weeks. The Kansas City Cardiomyopathy Questionnaire Total Symptom Score (KCCQ-TSS) was assessed at baseline and at 2, 4, 6, and 12 weeks. Longitudinal modeling assessed slope of KCCQ change across the study.

RESULTS

Among 448 individuals with HF (181 with HFrEF and 267 with HFpEF), participants with HFpEF had lower baseline KCCQ-TSS scores than those with HFrEF (54 ± 21 vs 64 ± 20). Modeling demonstrated initial rapid improvement in KCCQ-TSS in both HF groups, with deceleration over the next 4 to 6 weeks. The rate of change was greater among HFpEF participants (0.7 points/day; 95% CI: 0.3-1.1 points/day) than HFrEF participants (ΔKCCQ-TSS/day = 0.5; 95% CI: 0.1-1.0 points/day) randomized to canagliflozin, but these differences were not statistically significant (0.2 points/day; 95% CI: -0.4 to 0.7 points/day; P = 056).

CONCLUSIONS

After canagliflozin therapy, regardless of EF, modeling shows the KCCQ-TSS improves rapidly with the greatest improvements occurring within the first weeks of treatment. These results have implications for clinical use of SGLT2is and may be useful in the design of trials examining impact of these agents on health status in HF. (A Study on Impact of Canagliflozin on Health Status, Quality of Life, and Functional Status in Heart Failure [CHIEF-HF]; NCT04252287).

Obesity: the perfect storm for heart failure

Obesity condition causes morphological and functional alterations involving the cardiovascular system. These can represent the substrates for different cardiovascular diseases, such as atrial fibrillation, coronary artery disease, sudden cardiac death, and heart failure (HF) with both preserved ejection fraction (EF) and reduced EF. Different pathogenetic mechanisms may help to explain the association between obesity and HF including left ventricular remodelling and epicardial fat accumulation, endothelial dysfunction, and coronary microvascular dysfunction. Multi-imaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, with echocardiography being the most cost-effective technique. Therapeutic approach in patients with obesity and HF is challenging, particularly regarding patients with preserved EF in which few strategies with high level of evidence are available. Weight loss is of extreme importance in patients with obesity and HF, being a primary therapeutic intervention. Sodium-glucose co-transporter-2 inhibitors have been recently introduced as a novel tool in the management of HF patients. The present review aims at analysing the most recent studies supporting pathogenesis, diagnosis, and management in patients with obesity and HF.

Drug Safety Evaluation of Sodium-Glucose Cotransporter 2 Inhibitors in Diabetic Comorbid Patients by Review of Systemic Extraglycemic Effects

Purpose

The aim of this study is to evaluate the safety of this drug in diabetic patients with comorbidities of all systems.

Method

In this review, the beneficial effects of this drug and its mechanism on the disorders of every system of humans in relation to diabetes have been studied, and finally, its adverse effects have also been discussed. The search for relevant information is carried out in the PubMed and Google Scholar databases by using the following terms: diabetes mellitus type 2, SGLT, SGLT2 inhibitors, (SGLT2 inhibitors) AND (Pleiotropic effects). All English-published articles from 2016 to 2023 have been used in this study. It should be noted that a small number of articles published before 2016 have been used in the introduction and general informations.

Results

Its beneficial effects on improving cardiovascular disease risk factors and reducing adverse events caused by cardiovascular and renal diseases have proven in most large clinical studies that these effects are almost certain. It also has beneficial effects on other human systems such as the respiratory system, the gastrointestinal system, the circulatory system, and the nervous system; more of them are at the level of clinical and pre-clinical trials but have not been proven in large clinical trials or meta-analyses.

Conclusion

With the exception of a few adverse effects, this drug is considered a good choice and safe for all diabetic patients with comorbidities of all systems.

SGLT2 Inhibition and Kidney Potassium Homeostasis

Pharmacologic inhibition of the sodium-glucose transporter 2 (SGLT2) in the proximal tubule brings about physiologic changes predicted to both increase and decrease kidney K + excretion. Despite these effects, disorders of plasma K + concentration are an uncommon occurrence. If anything, these drugs either cause no effect or a slight reduction in plasma K + concentration in patients with normal kidney function but seem to exert a protective effect against hyperkalemia in the setting of reduced kidney function or when given with drugs that block the renin-angiotensin-aldosterone axis. In this review, we discuss the changes in kidney physiology after the administration of SGLT2 inhibitors predicted to cause both hypokalemia and hyperkalemia. We conclude that these factors offset one another, explaining the uncommon occurrence of dyskalemias with these drugs. Careful human studies focusing on the determinants of kidney K + handling are needed to fully understand how these drugs attenuate the risk of hyperkalemia and yet rarely cause hypokalemia.

Effects of Empagliflozin on Fluid Overload, Weight, and Blood Pressure in CKD

SIGNIFICANCE STATEMENT

SGLT2 inhibitors reduce risk of kidney progression, AKI, and cardiovascular disease, but the mechanisms of benefit are incompletely understood. Bioimpedance spectroscopy can estimate body water and fat mass. One quarter of the EMPA-KIDNEY bioimpedance substudy CKD population had clinically significant levels of bioimpedance-derived "Fluid Overload" at recruitment. Empagliflozin induced a prompt and sustained reduction in "Fluid Overload," irrespective of sex, diabetes, and baseline N-terminal pro B-type natriuretic peptide or eGFR. No significant effect on bioimpedance-derived fat mass was observed. The effects of SGLT2 inhibitors on body water may be one of the contributing mechanisms by which they mediate effects on cardiovascular risk.

BACKGROUND

CKD is associated with fluid excess that can be estimated by bioimpedance spectroscopy. We aimed to assess effects of sodium glucose co-transporter 2 inhibition on bioimpedance-derived "Fluid Overload" and adiposity in a CKD population.

METHODS

EMPA-KIDNEY was a double-blind placebo-controlled trial of empagliflozin 10 mg once daily in patients with CKD at risk of progression. In a substudy, bioimpedance measurements were added to the main trial procedures at randomization and at 2- and 18-month follow-up visits. The substudy's primary outcome was the study-average difference in absolute "Fluid Overload" (an estimate of excess extracellular water) analyzed using a mixed model repeated measures approach.

RESULTS

The 660 substudy participants were broadly representative of the 6609-participant trial population. Substudy mean baseline absolute "Fluid Overload" was 0.4±1.7 L. Compared with placebo, the overall mean absolute "Fluid Overload" difference among those allocated empagliflozin was -0.24 L (95% confidence interval [CI], -0.38 to -0.11), with similar sized differences at 2 and 18 months, and in prespecified subgroups. Total body water differences comprised between-group differences in extracellular water of -0.49 L (95% CI, -0.69 to -0.30, including the -0.24 L "Fluid Overload" difference) and a -0.30 L (95% CI, -0.57 to -0.03) difference in intracellular water. There was no significant effect of empagliflozin on bioimpedance-derived adipose tissue mass (-0.28 kg [95% CI, -1.41 to 0.85]). The between-group difference in weight was -0.7 kg (95% CI, -1.3 to -0.1).

CONCLUSIONS

In a broad range of patients with CKD, empagliflozin resulted in a sustained reduction in a bioimpedance-derived estimate of fluid overload, with no statistically significant effect on fat mass.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT03594110 ; EuDRACT: 2017-002971-24 ( https://eudract.ema.europa.eu/ ).

The Safety and Efficacy of Sodium-Glucose Cotransporter-2 Inhibitors for Patients with Sarcopenia or Frailty: Double Edged Sword?

Sodium-glucose cotransporter-2 inhibitors (SGLT-2is) show cardiovascular protective effects, regardless of the patient's history of diabetes mellitus (DM). SGLT2is suppressed cardiovascular adverse events in patients with type 2 DM, and furthermore, SGLT-2is reduced the risk of worsening heart failure (HF) events or cardiovascular death in patients with HF. Along with these research findings, SGLT-2is are recommended for patients with HF in the latest guidelines. Despite these benefits, the concern surrounding the increasing risk of body weight loss and other adverse events has not yet been resolved, especially for patients with sarcopenia or frailty. The DAPA-HF and DELIVER trials consistently showed the efficacy and safety of SGLT-2i for HF patients with frailty. However, the Rockwood frailty index that derived from a cumulative deficit model was employed for frailty assessment in these trials, which might not be suitable for the evaluation of physical frailty or sarcopenia alone. There is no fixed consensus on which evaluation tool to use or its cutoff value for the diagnosis and assessment of frailty in HF patients, or which patients can receive SGLT-2i safely. In this review, we summarize the methodology of frailty assessment and discuss the efficacy and safety of SGLT-2i for HF patients with sarcopenia or frailty.

Evaluation of Inpatient Sodium-Glucose Co-Transporter-2 Inhibitor Use in Patients Hospitalized for Acute Heart Failure

Hospitalization for acute heart failure (HF) represents an important opportunity for initiation and up-titration of guideline-directed medical therapy. This study aimed to determine whether sodium-glucose co-transporter-2 inhibitor (SGLT2I) use is safe in patients hospitalized for acute HF and whether its use is associated with improved clinical outcomes. We conducted a single-center, retrospective cohort study of adults hospitalized for acute HF with any ejection fraction and separated them into 2 matched groups based on inpatient SGLT2I use. The matching yielded 110 patients in the SGLT2I group and 110 patients in the control group. A total of 101 patients (91.8%) in the SGLT2I group were treated with dapagliflozin, whereas 9 (8.2%) were treated with empagliflozin. The mean age was 71 years, 37.7% were women, 70.9% were White, 22.7% were Black, and 64.1% were Hispanic or Latino. The length of stay was 10 days in the SGLT2I group and 11 days in the control group (p = 0.43). A total of 2 patients (1.8%) in the SGLT2I group and 13 patients (11.8%) in the control group died within 30 days of discharge (hazard ratio 0.15, 95% confidence interval [CI] 0.03 to 0.66, p = 0.012). A total of 17 patients (15.5%) in the SGLT2I group and 11 patients (10.0%) in the control group had an all-cause readmission within 30 days (hazard ratio 1.58, 95% CI 0.74 to 3.37, p = 0.239). In addition, 11 patients (10.0%) in the SGLT2I group and 3 patients (2.7%) in the control group had an HF readmission within 30 days (hazard ratio 3.75, 95% CI 1.05 to 13.44, p = 0.042). Acute kidney injury (54.5% vs 18.2%, p <0.001) and hypotension (12.7% vs 2.7%, p = 0.005) occurred significantly more frequently in the control group. In conclusion, SGLT2I use in patients hospitalized for acute HF was associated with decreased 30-day all-cause mortality and lower rates of acute kidney injury and hypotension; however, the rate of 30-day HF readmission increased.

Heart Failure with Preserved Ejection Fraction: The Pathophysiological Mechanisms behind the Clinical Phenotypes and the Therapeutic Approach

Heart failure (HF) with preserved ejection fraction (HFpEF) is an increasingly frequent form and is estimated to be the dominant form of HF. On the other hand, HFpEF is a syndrome with systemic involvement, and it is characterized by multiple cardiac and extracardiac pathophysiological alterations. The increasing prevalence is currently reaching epidemic levels, thereby making HFpEF one of the greatest challenges facing cardiovascular medicine today. Compared to HF with reduced ejection fraction (HFrEF), the medical attitude in the case of HFpEF was a relaxed one towards the disease, despite the fact that it is much more complex, with many problems related to the identification of physiopathogenetic mechanisms and optimal methods of treatment. The current medical challenge is to develop effective therapeutic strategies, because patients suffering from HFpEF have symptoms and quality of life comparable to those with reduced ejection fraction, but the specific medication for HFrEF is ineffective in this situation; for this, we must first understand the pathological mechanisms in detail and correlate them with the clinical presentation. Another important aspect of HFpEF is the diversity of patients that can be identified under the umbrella of this syndrome. Thus, before being able to test and develop effective therapies, we must succeed in grouping patients into several categories, called phenotypes, depending on the pathological pathways and clinical features. This narrative review critiques issues related to the definition, etiology, clinical features, and pathophysiology of HFpEF. We tried to describe in as much detail as possible the clinical and biological phenotypes recognized in the literature in order to better understand the current therapeutic approach and the reason for the limited effectiveness. We have also highlighted possible pathological pathways that can be targeted by the latest research in this field.

The impact of empagliflozin and metformin on cardiac parameters in patients with mid-range ejection fraction heart failure without diabetes

Heart failure (HF) remains a significant problem for healthcare systems, requiring the use of intervention and multimodal management strategies. We aimed to assess the short-term effect of empagliflozin (EMPA) and metformin on cardiac function parameters, including ventricular dimension-hypertrophy, septal thickness, ejection fraction (EF), and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in patients with HF and mildly reduced EF. A case-control study included 60 newly diagnosed patients with HF. Patients were divided into two groups: Group E received standard HF treatment (carvedilol, bumetanide, sacubitril-valsartan, spironolactone) plus EMPA 10 mg daily, and Group M received standard HF treatment plus metformin 500 mg daily. After three months of treatment, Group E had a significantly higher EF than Group M compared to initial measurements (a change of 9.2% versus 6.1%, respectively). We found similar results in the left ventricular end-systolic dimension (LVESD), with mean reductions of 0.72 mm for Group E and 0.23 mm for Group M. Regarding cardiac indicators, the level of NT-proBNP was considerably decreased in both groups. However, the reduction was significantly greater in group E than in group M compared to the initial level (mean reduction: 719.9 vs. 973.6, respectively). When combined with quadruple anti-heart failure therapy, metformin enhanced several echocardiographic parameters, showing effects similar to those of EMPA when used in the same treatment regimen. However, the benefits of EMPA were more pronounced, particularly regarding improvements in EF and LVESD.

Potential Underlying Mechanisms Explaining the Cardiorenal Benefits of Sodium-Glucose Cotransporter 2 Inhibitors

There is a bidirectional pathophysiological interaction between the heart and the kidneys, and prolonged physiological stress to the heart and/or the kidneys can cause adverse cardiorenal complications, including but not limited to subclinical cardiomyopathy, heart failure and chronic kidney disease. Whilst more common in individuals with Type 2 diabetes, cardiorenal complications also occur in the absence of diabetes. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) were initially approved to reduce hyperglycaemia in patients with Type 2 diabetes. Recently, these agents have been shown to significantly improve cardiovascular and renal outcomes in patients with and without Type 2 diabetes, demonstrating a robust reduction in hospitalisation for heart failure and reduced risk of progression of chronic kidney disease, thus gaining approval for use in treatment of heart failure and chronic kidney disease. Numerous potential mechanisms have been proposed to explain the cardiorenal effects of SGLT2i. This review provides a simplified summary of key potential cardiac and renal mechanisms underlying the cardiorenal benefits of SGT2i and explains these mechanisms in the clinical context. Key mechanisms related to the clinical effects of SGLT2i on the heart and kidneys explained in this publication include their impact on (1) tissue oxygen delivery, hypoxia and resultant ischaemic injury, (2) vascular health and function, (3) substrate utilisation and metabolic health and (4) cardiac remodelling. Knowing the mechanisms responsible for SGLT2i-imparted cardiorenal benefits in the clinical outcomes will help healthcare practitioners to identify more patients that can benefit from the use of SGLT2i.

Dapagliflozin-Induced Myocardial Flow Reserve Improvement is not Associated with HDL Ability to Stimulate Endothelial Nitric Oxide Production

BACKGROUND

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have shown controversial results in modulating plasma lipids in clinical trials. Most studies found slight increases in high-density lipoprotein (HDL) cholesterol but few have provided evidence on HDL functionality with disappointing results. However, there is broad agreement that these drugs provide cardiovascular protection through several mechanisms. Our group demonstrated that dapagliflozin improves myocardial flow reserve (MFR) in patients with type 2 diabetes (T2D) with coronary artery disease (CAD). The underlying mechanisms are still unknown, although in vitro studies have suggested the involvement of nitric oxide (NO).

AIM

To investigate changes in HDL-mediated modulation of NO production with dapagliflozin and whether there is an association with MFR.

METHODS

Sixteen patients with CAD-T2D were enrolled and randomized 1:1 to dapagliflozin or placebo for 4 weeks. Blood samples were collected before and after treatment for each group. The ability of HDL to stimulate NO production in endothelial cells was tested in vitro by incubating human umbilical vein endothelial cells (HUVEC) with apoB-depleted (apoB-D) serum of these patients. The production of NO was assessed by fluorescent assay, and results were expressed as fold versus untreated cells.

RESULTS

Change in HDL-mediated NO production remained similar in dapagliflozin and placebo group, even after adjustment for confounders. There were no significant correlations between HDL-mediated NO production and MFR either at baseline or after treatment. No changes were found in HDL cholesterol in either group, while low-density lipoprotein cholesterol (LDL cholesterol) significantly decreased compared to baseline only in treatment group (p = 0.043).

CONCLUSIONS

In patients with T2D-CAD, beneficial effects of dapagliflozin on coronary microcirculation seem to be unrelated to HDL functions. However, HDL capacity to stimulate NO production is not impaired at baseline; thus, the effect of drug treatments would be negligible. To conclude, we can assume that HDL-independent molecular pathways are involved in the improvement of MFR in this population.

TRIAL REGISTRATION

EudraCT No. 2016-003614-27; ClinicalTrials.gov Identifier: NCT03313752.

Cardioprotective Effects of Sodium-Glucose Cotransporter 2 Inhibitors and Their Possible Association With Normalization of the Circadian Index of Heart Rhythm

BACKGROUND

Updated recommendations for the treatment of heart failure with reduced ejection fraction (HFrEF) include sodium-glucose cotransporter 2 (SGLT2) inhibitors and other long-established HFrEF therapies. These drugs' mechanisms of action have yet to be fully clarified.

OBJECTIVE

This study evaluated the effects of SGLT2 inhibitors on the modulation of autonomic function at 1 month beyond conventional HF therapy.

METHODS

This single-center, observational, prospective study was conducted from January 2020 to December 2022. Patients with type 2 diabetes who had ischemic HFrEF and met the study criteria were considered for SGLT2 inhibitor treatment with empagliflozin or dapagliflozin. Changes in the circadian index were used as the primary outcome to assess the early effects of SGLT2 inhibitors on autonomic function. Changes in functional effort capacity and laboratory findings were also evaluated. Participants' circadian index was measured by a 24-hour rhythm Holter monitoring recorder (BTL-08 Holter H100). A symptom-limited treadmill test assessed patients' effort capacities. Tests were repeated after 1 month of therapy.

RESULTS

The mean (SD) age of the 151 participants was 56.95 (7.29) years; their mean (SD) left ventricular EF was 35.69% (7.10%), and 95 participants were men (62.9%). From baseline to 1 month, mean (SD) daytime heart rate (80.63 [9.17] vs 77.67 [8.04] beats per minute; P = .004) and nighttime heart rate (76.83 [11.34] vs 73.81 [10.25] beats per minute; P = .03) decreased significantly. Variation in the circadian indexes (mean [SD], 1.04 [0.02] vs 1.10 [0.04]; P < .001) was statistically significant, favoring increased modulation of autonomic function. The increases in exercise duration (mean [SD], 8.88 [3.69] minutes and median [IQR], 8.81 [5.76-12.13] minutes vs 9.72 [3.14] and 9.59 [7.24-12.22] minutes; P = .04) and exercise capacity (mean [SD], 203.38 [65.18] m and median [IQR], 119.22 [149.43-259.15] m vs 335.61 [51.39] and 325.79 [293.59-376.91] m; P < .001] were also significant.

CONCLUSION

The use of SGLT2 inhibitors during early treatment can favorably affect both autonomic dysfunction and functional effort capacity of patients with type 2 diabetes with ischemic HFrEF.

Blood Pressure Effects of SGLT2 Inhibitors: Mechanisms and Clinical Evidence in Different Populations

PURPOSE OF REVIEW

Sodium glucose transporter 2 inhibitors (SGLT2 inhibitors) are increasingly prescribed due to their considerable benefits on clinical outcomes in people with diabetes, heart failure, and chronic kidney disease (CKD). Hypertension is a common comorbidity in each of these disease states, increasing risk of cardiovascular morbidity and mortality. We herein review the effects of SGLT2 inhibitors on blood pressure in different populations, proposed mechanisms of action, and the contribution of blood pressure lowering to end-organ protection.

RECENT FINDINGS

A recognised effect of SGLT2 inhibitors in recent clinical trials is blood pressure lowering, with multiple postulated mechanisms. This advantageous effect was first identified in populations with type 2 diabetes mellitus, prior to expansion of these trials to broader cohorts. On our review, we identified that the blood pressure lowering effect of SGLT2 inhibitors appears to be a dose-independent class-effect, with a magnitude of effect comparable to that seen with a low dose hydrochlorothiazide. There is considerable evidence demonstrating that this effect is observed across populations including those with type 2 diabetes mellitus, chronic kidney disease, and resistant hypertension.

Zibotentan in combination with dapagliflozin compared with dapagliflozin in patients with chronic kidney disease (ZENITH-CKD): a multicentre, randomised, active-controlled, phase 2b, clinical trial

BACKGROUND

In patients with chronic kidney disease, SGLT2 inhibitors and endothelin A receptor antagonists (ERAs) can reduce albuminuria and glomerular filtration rate (GFR) decline. We assessed the albuminuria-lowering efficacy and safety of the ERA zibotentan combined with the SGLT2 inhibitor dapagliflozin.

METHODS

ZENITH-CKD was a multicentre, randomised, double-blind, active-controlled clinical trial, done in 170 clinical practice sites in 18 countries. Adults (≥18 to ≤90 years) with an estimated GFR (eGFR) of 20 mL/min per 1·73 m2 or greater and a urinary albumin-to-creatinine ratio (UACR) of 150-5000 mg/g were randomly assigned (2:1:2) to 12 weeks of daily treatment with zibotentan 1·5 mg plus dapagliflozin 10 mg, zibotentan 0·25 mg plus dapagliflozin 10 mg, or dapagliflozin 10 mg plus placebo, as adjunct to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers if tolerated. The primary endpoint was a change from baseline in log-transformed UACR (zibotentan 1·5 mg plus dapagliflozin vs dapagliflozin plus placebo) at week 12. Fluid retention was an event of special interest, defined as an increase in bodyweight of at least 3% (at least 2·5% must have been from total body water) from baseline or an increase of at least 100% in B-type natriuretic peptide (BNP) and either a BNP concentration greater than 200 pg/mL if without atrial fibrillation or BNP greater than 400 pg/mL if with atrial fibrillation. This trial is registered with ClinicalTrials.gov, NCT04724837, and is completed.

FINDINGS

Between April 28, 2021, and Jan 17, 2023, we assessed 1492 participants for eligibility. For the main analysis, we randomly assigned 449 (30%) participants, 447 (99%) of whom (mean age 62·8 years [SD 12·1], 138 [31%] female, 309 [69%] male, 305 [68%] White, mean eGFR 46·7 mL/min per 1·73 m2 [SD 22·4], and median UACR 565·5 mg/g [IQR 243·0-1212·6]) received treatment with zibotentan 1·5 mg plus dapagliflozin (n=179 [40%]), zibotentan 0·25 mg plus dapagliflozin (n=91 [20%]), or dapagliflozin plus placebo (n=177 [40%]). Zibotentan 1·5 mg plus dapagliflozin and zibotentan 0·25 mg plus dapagliflozin reduced UACR versus dapagliflozin plus placebo throughout the treatment period of the study. At week 12, the difference in UACR versus dapagliflozin plus placebo was -33·7% (90% CI -42·5 to -23·5; p<0·0001) for zibotentan 1·5 mg plus dapagliflozin and -27·0% (90% CI -38·4 to -13·6; p=0·0022) for zibotentan 0·25 mg plus dapagliflozin. Fluid-retention events were observed in 33 (18%) of 179 participants in the zibotentan 1·5 mg plus dapagliflozin group, eight (9%) of 91 in the zibotentan 0·25 mg plus dapagliflozin group, and 14 (8%) of 177 in the dapagliflozin plus placebo group.

INTERPRETATION

Zibotentan combined with dapagliflozin reduced albuminuria with an acceptable tolerability and safety profile and is an option to reduce chronic kidney disease progression in patients already receiving currently recommended therapy.

FUNDING

AstraZeneca.

Protective effect of canagliflozin on post-resuscitation myocardial function in a rat model of cardiac arrest

BACKGROUND

Currently, most patients with cardiac arrest (CA) show reversible myocardial dysfunction, hemodynamic instability, systemic inflammation and other pathophysiological state in early stage of resuscitation, some patients may eventually progress to multiple organ failure. There is evidence that heart failure is the terminal stage in the development of various cardiovascular diseases. Although the cardio-protective effect of canagliflozin (CANA) has been confirmed in large clinical studies and recommended in domestic and international heart failure-related guidelines, the effectiveness of CANA after resuscitation remains unclear. In this study, we constructed a modified CA/CPR rat model to investigate whether CANA administered on post-resuscitation improves myocardial function.

METHODS

Twenty-fourth healthy male Sprague-Dawley rats were randomized into four groups: (1) Sham + placebo group, (2) Sham + CANA group, (3) CPR + placebo group, and (4) CPR + CANA group. Ventricular fibrillation was induced by transcutaneous electrical stimulation on epicardium. After 6 min untreated ventricular fibrillation, chest compressions was initiated. The rats were received an injection of placebo or canagliflozin (3 ug/kg) randomly 15 min after restore of spontaneous circulation (ROSC). Electrocardiogram (ECG) and blood pressure were continuously detected in each group throughout the experiment. The rats were killed 6 h after ROSC to collected the arterial serum and myocardial tissue. Myocardial injury was estimated with concentrations of inflammatory factors, oxidative stress indexes and, apoptosis index, myocardial injury markers, echocardiography and myocardial pathological slices.

RESULTS

After resuscitation, mean arterial pressure (MAP) were significantly increased after cardiopulmonary resuscitation in CANA group rats when compared with placebo group. Heart rate, body lactate returned and left ventricular ejection fraction (LVEF) to normal levels in a shorter time and the myocardial injury was obviously attenuated in CPR + CANA group. Inflammatory factors (IL-6, TNF-α) and oxidative stress indexes (MAD, SOD, CAT) were dramatically decreased with the administration of CANA. The expression of apoptosis index (BAX, caspase-3) were higher in CPR + placebo group and the expression of anti-apoptosis index (Bcl-2) was lower (P < 0.05).

CONCLUSIONS

The administration of CANA effectively reduces myocardial ischaemia/reperfusion (I/R) injury after cardiac arrest and cardiopulmonary resuscitation (CPR), and the underlying mechanism may be related to anti-inflammation, oxidative stress and apoptosis.

Management of Hypertension in Diabetic Kidney Disease

Hypertension is a critical component of cardiovascular disease progression in patients with chronic kidney disease, and specifically diabetic kidney disease (DKD). Causation versus correlation remains up for debate, but what has been confirmed is the delay of DKD progression when hypertension is controlled or moved to guideline drive ranges. Many medications have been studied and used in real world experience for best outcomes, and we discuss below the proven winners thus far making up the renin angiotensin aldosterone system. As well, we discuss guideline changing medications including sodium-glucose cotransporter 2 inhibitors and newer generation mineralocorticoid receptor antagonists. With the growing prevalence of diabetes and DKD in the population, newer agents are emerging in multiple drug class and will be highlighted below. Clinicians continue to search for the optimal care plans for this challenging patient population.

The effects of empagliflozin on measured glomerular filtration rate and estimated extracellular and plasma volumes in patients with type 2 diabetes

AIMS

To investigate the effects of empagliflozin on measured glomerular filtration rate (mGFR), estimated plasma volume (PV) and estimated extracellular volume (ECV) in a cohort of patients with type 2 diabetes (T2D) and high risk of cardiovascular events.

MATERIALS AND METHODS

In this prespecified substudy of the randomized, placebo-controlled SIMPLE trial, patients with T2D at high risk of cardiovascular events were allocated to either empagliflozin 25 mg or placebo once daily for 13 weeks. The prespecified outcome was between-group change in mGFR, measured by the 51 Cr-EDTA method after 13 weeks; changes in estimated PV and estimated ECV were included.

RESULTS

From April 4, 2017 to May 11, 2020, 91 participants were randomized. Of these, 45 patients from the empagliflozin group and 45 patients from the placebo group were included in the intention-to-treat analysis. Treatment with empagliflozin reduced mGFR by -7.9 mL/min (95% confidence interval [CI] -11.1 to -4.7; P < 0.001), estimated ECV by -192.5 mL (95% CI -318.0 to -66.9; P = 0.003) and estimated PV by -128.9 mL (95% CI -218.0 to 39.8; P = 0.005) at Week 13.

CONCLUSIONS

Treatment with empagliflozin for 13 weeks reduced mGFR, estimated ECV and estimated PV in patients with T2D and high risk of cardiovascular events.

The Importance of Optimal Hydration in Patients with Heart Failure-Not Always Too Much Fluid

Heart failure (HF) is a leading cause of morbidity and mortality and a major public health problem. Both overhydration and dehydration are non-physiological states of the body that can adversely affect human health. Congestion and residual congestion are common in patients hospitalized for HF and are associated with poor prognosis and high rates of rehospitalization. However, the clinical problem of dehydration is also prevalent in healthcare and community settings and is associated with increased morbidity and mortality. This article provides a comprehensive review of the issue of congestion and dehydration in HF, including HF guidelines, possible causes of dehydration in HF, confirmed and potential new diagnostic methods. In particular, a full database search on the relationship between dehydration and HF was performed and all available evidence in the literature was reviewed. The novel hypothesis of chronic subclinical hypohydration as a modifiable risk factor for HF is also discussed. It is concluded that maintaining euvolemia is the cornerstone of HF management. Physicians have to find a balance between decongestion therapy and the risk of dehydration.

Acute effects of empagliflozin on open-loop baroreflex function and urinary glucose excretion in rats with chronic myocardial infarction

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have exerted cardioprotective effects in clinical trials, but underlying mechanisms are not fully understood. As mitigating sympathetic overactivity is of major clinical concern in the mechanisms of heart failure treatments, we examined the effects of modulation of glucose handling on baroreflex-mediated sympathetic nerve activity and arterial pressure regulations in rats with chronic myocardial infarction (n = 9). Repeated 11-min step input sequences were used for an open-loop analysis of the carotid sinus baroreflex. An SGLT2 inhibitor, empagliflozin, was intravenously administered (10 mg/kg) after the second sequence. Neither the baroreflex neural nor peripheral arc significantly changed during the last observation period (seventh and eighth sequences) compared with the baseline period although urinary glucose excretion increased from near 0 (0.0089 ± 0.0011 mg min-1 kg-1) to 1.91 ± 0.25 mg min-1 kg-1. Hence, empagliflozin does not acutely modulate the baroreflex regulations of sympathetic nerve activity and arterial pressure in this rat model of chronic myocardial infarction.

Effect of Dapagliflozin on Patients with Rheumatic Heart Disease Mitral Stenosis

(1) Background: Mitral stenosis is the most common rheumatic heart disease (RHD). Inflammation and fibrosis are the primary pathophysiology, resulting in left atrial stress and dysfunction. Dapagliflozin is a new heart failure treatment with anti-inflammation and anti-fibrosis effects from previous studies. However, the specific role of dapagliflozin in RHD mitral stenosis is unknown. This study aims to investigate (i) the effect of dapagliflozin on biomarkers of fibrosis, NT-pro BNP levels and left atrial function; (ii) the relationship between the changes in fibrosis biomarkers with left atrial function and NT-pro BNP levels. (2) Methods: An open-label randomized study was conducted on 33 RHD mitral stenosis patients divided into a dapagliflozin group which received 10 mg dapagliflozin and standard therapy, and a control group which only received standard therapy. All patients were examined for levels of PICP, MMP-1/TIMP-1 ratio, TGF-β1, NT-proBNP, mitral valve mean pressure gradient (MPG), and net atrioventricular compliance (Cn) pre- and post-intervention. (3) Results: This study found a significant increase in PICP and TGF-β1 and a reduction in the MMP-1/TIMP-1 ratio in the dapagliflozin group and the control group (p < 0.05). In the dapagliflozin group, the levels of NT-pro BNP decreased significantly (p = 0.000), with a delta of decreased NT-pro BNP levels also significantly greater in the dapagliflozin group compared to the control (p = 0.034). There was a significant increase in Cn values in the dapagliflozin group (p = 0.017), whereas there was a decrease in the control group (p = 0.379). Delta of changes in Cn values between the dapagliflozin and control groups also showed a significant value (p = 0.049). The decreased MPG values of the mitral valve were found in both the dapagliflozin and control groups, with the decrease in MPG significantly greater in the dapagliflozin group (p = 0.031). There was no significant correlation between changes in the value of fibrosis biomarkers with Cn and NT-pro BNP (p > 0.05). (4) Conclusions: This study implies that the addition of dapagliflozin to standard therapy for RHD mitral stenosis patients provides benefits, as evidenced by an increase in net atrioventricular compliance and decreases in the MPG value of the mitral valve and NT-pro BNP levels (p < 0.05). This improvement was not directly related to changes in fibrosis biomarkers, as these biomarkers showed ongoing fibrosis even with dapagliflozin administration.

Sodium-glucose cotransporter-2 inhibitors in heart failure: Potential decongestive mechanisms and current clinical studies

Congestion is a key pathophysiological feature of heart failure (HF) syndrome that drives most of the clinical manifestations of acute HF and is related with poor quality of life and outcomes. Therefore, safe and effective decongestion is an important therapeutic target in the management of acute HF and despite the use of guideline-recommended loop diuretics, adequate decongestion is not always achieved in patients with acute HF. Recently, sodium-glucose cotransporter-2 (SGLT-2) inhibitors have been shown to provide clinical benefits across a broad spectrum of patients with HF, including consistent reduction in the risk of acute HF episodes. While the exact mechanisms underlying these benefits remain a matter of debate, a growing body of evidence suggests that effective decongestion may be partly responsible, especially in the setting of acute HF. In this review, we discuss the potential decongestive mechanisms of SGLT-2 inhibitors, such as osmotic diuresis, natriuresis, preservation of glomerular filtration and facilitation of interstitial drainage, which can collectively translate into effective and safe decongestion. Furthermore, we provide a comprehensive review of up-to-date clinical data of SGLT-2 inhibitor use in the acute HF population.

Reno- and cardioprotective molecular mechanisms of SGLT2 inhibitors beyond glycemic control: from bedside to bench

Large placebo-controlled clinical trials have shown that sodium-glucose cotransporter-2 inhibitors (SGLT2i) delay the deterioration of renal function and reduce cardiovascular events in a glucose-independent manner, thereby ultimately reducing mortality in patients with chronic kidney disease (CKD) and/or heart failure. These existing clinical data stimulated preclinical studies aiming to understand the observed clinical effects. In animal models, it was shown that the beneficial effect of SGLT2i on the tubuloglomerular feedback (TGF) improves glomerular pressure and reduces tubular workload by improving renal hemodynamics, which appears to be dependent on salt intake. High salt intake might blunt the SGLT2i effects on the TGF. Beyond the salt-dependent effects of SGLT2i on renal hemodynamics, SGLT2i inhibited several key aspects of macrophage-mediated renal inflammation and fibrosis, including inhibiting the differentiation of monocytes to macrophages, promoting the polarization of macrophages from a proinflammatory M1 phenotype to an anti-inflammatory M2 phenotype, and suppressing the activation of inflammasomes and major proinflammatory factors. As macrophages are also important cells mediating atherosclerosis and myocardial remodeling after injury, the inhibitory effects of SGLT2i on macrophage differentiation and inflammatory responses may also play a role in stabilizing atherosclerotic plaques and ameliorating myocardial inflammation and fibrosis. Recent studies suggest that SGLT2i may also act directly on the Na+/H+ exchanger and Late-INa in cardiomyocytes thus reducing Na+ and Ca2+ overload-mediated myocardial damage. In addition, the renal-cardioprotective mechanisms of SGLT2i include systemic effects on the sympathetic nervous system, blood volume, salt excretion, and energy metabolism.

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.

Sotagliflozin vs Dapagliflozin: A Systematic Review Comparing Cardiovascular Mortality

After the debut of the results of the effect of Sotagliflozin on Cardiovascular Events in Patients with Type 2 Diabetes Post Worsening Heart Failure (SOLOIST-WHF) and Sotagliflozin in Patients With Chronic Kidney Disease and Type 2 Diabetes (SCORED) trials at the American Heart Association's 2020 Scientific session, sotagliflozin became the first drug and the third sodium glucose co-transporter-2 (SGLT-2) inhibitor to be approved for heart failure (HF) across the spectrum of ejection fraction (EF). In light of this recent major U.S. Food and Drug Administration (FDA) approval of sotagliflozin, we conducted a systematic review to compare the cardiovascular mortality rates between sotagliflozin and dapagliflozin in patients with HF. To find relevant articles, we extensively searched major research literature databases and search engines such as PubMed, MEDLINE, PubMed Central, Google Scholar, Embase, and Cochrane Library. We compared the results of significant trials involving sotagliflozin with the trials studying dapagliflozin to provide comprehensive mortality results of both drugs. The results showed that the timely initiation of sotagliflozin in HF cases significantly reduces cardiovascular mortality, hospitalizations, and urgent HF visits. Comparative trials with dapagliflozin indicate enhanced mortality reduction associated with greater initial symptom burden. The results of these major trials cannot be overlooked due to the large size of the combined trials, the randomized design, and the high standards with which they were conducted. The pathophysiology behind the cardioprotection offered by these agents is complex and multifactorial, but it is believed that due to the diuretic-like function, SGLT-2 inhibitors reduce glycemic-related toxicity, promote ketogenesis, and exert antihypertrophic, antifibrotic, and anti-remodeling properties. The benefits of dapagliflozin on cardiovascular death and worsening HF in patients with mildly reduced or preserved EF appeared especially pronounced in those with a greater degree of symptomatic impairment at baseline. Sotagliflozin led to a rise in the count of days patients were alive and not hospitalized (DAOH), which offers an extra patient-centered measure to assess the impact of the disease burden. The data in our article will help future researchers conduct large-scale trials with sotagliflozin to identify and implement it in the treatment of patients with HF as a mortality-reducing drug and to improve the quality of life for patients with HF.

Dapagliflozin vs. metolazone in heart failure resistant to loop diuretics

BACKGROUND AND AIMS

To examine the decongestive effect of the sodium-glucose cotransporter 2 inhibitor dapagliflozin compared to the thiazide-like diuretic metolazone in patients hospitalized for heart failure and resistant to treatment with intravenous furosemide.

METHODS AND RESULTS

A multi-centre, open-label, randomized, and active-comparator trial. Patients were randomized to dapagliflozin 10 mg once daily or metolazone 5-10 mg once daily for a 3-day treatment period, with follow-up for primary and secondary endpoints until day 5 (96 h). The primary endpoint was a diuretic effect, assessed by change in weight (kg). Secondary endpoints included a change in pulmonary congestion (lung ultrasound), loop diuretic efficiency (weight change per 40 mg of furosemide), and a volume assessment score. 61 patients were randomized. The mean (±standard deviation) cumulative dose of furosemide at 96 h was 977 (±492) mg in the dapagliflozin group and 704 (±428) mg in patients assigned to metolazone. The mean (±standard deviation) decrease in weight at 96 h was 3.0 (2.5) kg with dapagliflozin compared to 3.6 (2.0) kg with metolazone [mean difference 0.65, 95% confidence interval (CI) -0.12,1.41 kg; P = 0.11]. Loop diuretic efficiency was less with dapagliflozin than with metolazone [mean 0.15 (0.12) vs. 0.25 (0.19); difference -0.08, 95% CI -0.17,0.01 kg; P = 0.10]. Changes in pulmonary congestion and volume assessment score were similar between treatments. Decreases in plasma sodium and potassium and increases in urea and creatinine were smaller with dapagliflozin than with metolazone. Serious adverse events were similar between treatments.

CONCLUSION

In patients with heart failure and loop diuretic resistance, dapagliflozin was not more effective at relieving congestion than metolazone. Patients assigned to dapagliflozin received a larger cumulative dose of furosemide but experienced less biochemical upset than those assigned to metolazone.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04860011.

Cardiovascular and renal effects of SGLT2 inhibitor initiation in acute heart failure: a meta-analysis of randomized controlled trials

BACKGROUND

We sought to compare cardiovascular outcomes, renal function, and diuresis in patients receiving standard diuretic therapy for acute heart failure (AHF) with or without the addition of SGLT2i.

METHODS AND RESULTS

Systematic search of three electronic databases identified nine eligible randomized controlled trials involving 2,824 patients. The addition of SGLT2i to conventional therapy for AHF reduced all-cause death (odds ratio [OR] 0.75; 95% CI 0.56-0.99; p = 0.049), readmissions for heart failure (HF) (OR 0.54; 95% CI 0.44-0.66; p < 0.001), and the composite of cardiovascular death and readmissions for HF (hazard ratio 0.71; 95% CI 0.60-0.84; p < 0.001). Furthermore, SGLT2i increased mean daily urinary output in liters (mean difference [MD] 0.45; 95% CI 0.03-0.87; p = 0.035) and decreased mean daily doses of loop diuretics in mg of furosemide equivalent (MD -34.90; 95% CI [- 52.58, - 17.21]; p < 0.001) without increasing the incidence worsening renal function (OR 0.75; 95% CI 0.43-1.29; p = 0.290).

CONCLUSION

SGLT2i addition to conventional diuretic therapy reduced all-cause death, readmissions for HF, and the composite of cardiovascular death or readmissions for HF. Moreover, SGLT2i was associated with a higher volume of diuresis with a lower dose of loop diuretics.

Association of sodium-glucose cotransporter 2 inhibitors with post-discharge outcomes in patients with acute heart failure with type 2 diabetes: a cohort study

BACKGROUND

Given the cumulative evidence on the effectiveness of sodium-glucose cotransporter 2 inhibitors (SGLT2is) on chronic heart failure, demand is emerging for further information on their effects in patients who are hospitalized for acute heart failure. However, there is still limited evidence about the class effect of SGLT2is on acute heart failure. We investigated whether initiating treatment with SGLT2is after an episode of acute heart failure reduces the risks of post-discharge heart failure readmission or cardiovascular mortality among patients with type 2 diabetes.

METHODS

A retrospective cohort study was conducted in a cohort of patients with type 2 diabetes who hospitalized for heart failure, using Korean Health Insurance Review & Assessment database (2015-2020). The exposure was defined as initiation of SGLT2is during hospitalization or at discharge. We assessed hazards of post-discharge heart failure readmission and cardiovascular death at 1-year, and 30-, 60-, and 90-day from the date of discharge in the SGLT2is users and non-users. Cox proportional hazards models with propensity score-based inverse probability of treatment weighting were used to estimate hazard ratios and 95% confidence intervals.

RESULTS

Among 56,343 patients with type 2 diabetes hospitalized for heart failure, 29,290 patients were included in the study cohort (mean [SD] age, 74.1 [10.8] years; 56.1% women); 818 patients (2.8%) were prescribed SGLT2is during index hospitalization or at discharge. Patients with a prescription for SGLT2i vs. those without prescription had lower rates of heart failure readmission or cardiovascular death at 1 year (22.4% vs. 25.3%; adjusted hazard ratio, 0.90 [95% confidence interval, 0.87-0.93]), and also at 30 days (7.0% vs. 7.7%%; 0.74 [0.69-0.79]).

CONCLUSIONS

Among patients with type 2 diabetes, initiating SGLT2i treatment after an episode of acute heart failure was significantly associated with a reduced combined risk of heart failure readmission and cardiovascular mortality in a nationwide cohort reflecting routine clinical practice.

Critical Analysis of the Effects of SGLT2 Inhibitors on Renal Tubular Sodium, Water and Chloride Homeostasis and Their Role in Influencing Heart Failure Outcomes

SGLT2 (sodium-glucose cotransporter 2) inhibitors interfere with the reabsorption of glucose and sodium in the early proximal renal tubule, but the magnitude and duration of any ensuing natriuretic or diuretic effect are the result of an interplay between the degree of upregulation of SGLT2 and sodium-hydrogen exchanger 3, the extent to which downstream compensatory tubular mechanisms are activated, and (potentially) the volume set point in individual patients. A comprehensive review and synthesis of available studies reveals several renal response patterns with substantial variation across studies and clinical settings. However, the common observation is an absence of a large acute or chronic diuresis or natriuresis with these agents, either when given alone or combined with other diuretics. This limited response results from the fact that renal compensation to these drugs is rapid and nearly complete within a few days or weeks, preventing progressive volume losses. Nevertheless, the finding that fractional excretion of glucose and lithium (the latter being a marker of proximal sodium reabsorption) persists during long-term treatment with SGLT2 inhibitors indicates that pharmacological tolerance to the effects of these drugs at the level of the proximal tubule does not meaningfully occur. This persistent proximal tubular effect of SGLT2 inhibitors can be hypothesized to produce a durable improvement in the internal set point for volume homeostasis, which may become clinically important during times of fluid expansion. However, it is difficult to know whether a treatment-related change in the volume set point actually occurs or contributes to the effect of these drugs to reduce the risk of major heart failure events. SGLT2 inhibitors exert cardioprotective effects by a direct effect on cardiomyocytes that is independent of the presence of or binding to SGLT2 or the actions of these drugs on the proximal renal tubule. Nevertheless, changes in the volume set point mediated by SGLT2 inhibitors might potentially act cooperatively with the direct favorable molecular and cellular effects of these drugs on cardiomyocytes to mediate their benefits on the development and clinical course of heart failure.

Comprehensive review of SGLT2 inhibitors' efficacy through their diuretic mode of action in diabetic patients

SGLT2 inhibitors (SGLT2i) are now the mainstay therapy for both diabetes and heart failure. Post-hoc publications, meta-analysis, and conference presentations of the eight SGLT2i Cardiovascular Outcomes trials (CVOTS) done in diabetic patients constantly echo that this class of drug decreases mortality, reduces cardiovascular events, and prevents heart failure and kidney disease. This review of medical agencies' SGLT2i analysis (FDA and EMA) helps to understand the reality of SGLT2i results in those trials, avoiding to consider observational and statistically undemonstrated endpoints as validated. They also confirmed the unique diuretic mode of action of SGLT2i, promoting osmotic diuresis, and its potential adverse events secondary to hypovolemia and hematocrit increase. They also support the understanding that the beliefs in SGLT2i morbi-mortality benefits are largely overstated mostly based on undemonstrated endpoints. Finally, it is clear that SGLT2i's antidiabetic action, secondary to its renal mode of action, plateaued after a few months and decreased strongly over time, questioning its long-term goal of maintaining diabetic patients' HbA1c below 7%. Also, this effect in patients with renal impairment is quasi null. We think that this review would be very helpful to every physician treating diabetic patients to better balance belief and reality of SGLT2i prescription effects.

Association of Carbohydrate Antigen 125 on the Response to Dapagliflozin in Patients With Heart Failure

BACKGROUND

Elevated circulating carbohydrate antigen 125 (CA125) is a marker of congestion and a predictor of outcomes in acute heart failure (HF). Less is known about CA125 in chronic ambulatory HF with reduced ejection fraction.

OBJECTIVES

This study examined the association between baseline CA125 (and changes in CA125) and outcomes in patients with HF with reduced ejection fraction in the DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure; NCT03036124) trial and its relationship with the effect of dapagliflozin.

METHODS

The primary outcome was a composite of a first episode of worsening HF or cardiovascular death. CA125 was measured at baseline and 12 months following randomization.

RESULTS

Median baseline CA125 was 13.04 U/mL (IQR: 8.78-21.13 U/mL) in 3,123 of 4,774 patients with available data. Compared with CA125 ≤35 U/mL (upper limit of normal), patients with CA125 >35 U/mL were at a higher risk of the primary outcome (adjusted HR: 1.59; 95% CI: 1.29-1.96). The adjusted risks of the primary outcome relative to quartile 1 (Q1) (≤8.78 U/mL) were as follow: Q2, 8.79-13.04 U/mL (HR: 0.94; 95% CI: 0.71-1.24); Q3, 13.05-21.13 U/mL (HR: 1.22; 95% CI: 0.94-1.59); Q4, ≥21.14 U/mL (HR: 1.63; 95% CI: 1.28-2.09). The beneficial effect of dapagliflozin compared with placebo on the primary outcome was consistent whether CA125 was analyzed in quartiles (interaction P = 0.13) or as a continuous variable (interaction P = 0.75). The placebo-corrected relative change in CA125 at 12 months was -5.2% (95% CI: -10.6% to 0.5%; P = 0.07).

CONCLUSIONS

In DAPA-HF, elevated CA125 levels were an independent predictor of the risk of worsening HF or cardiovascular death. Dapagliflozin reduced the risk of worsening HF or cardiovascular death regardless of baseline CA125.

Long-term observation of estimated fluid volume reduction after the initiation of ipragliflozin in patients with type 2 diabetes mellitus: a sub-analysis from a randomized controlled trial (PROTECT)

BACKGROUNDS/AIM

Recent studies have shown that the addition of sodium-glucose co-transporter 2 (SGLT2) inhibitors gradually reduces the estimated fluid volume parameters in a broad range of patient populations, suggesting that this mediates the clinical benefits of SGLT2 inhibitors in preventing heart failure. Here, we sought to examine the long-term (24 months) effect of the SGLT2 inhibitor ipragliflozin on the estimated fluid volume parameters in patients with type 2 diabetes mellitus (T2DM).

METHODS

In this prespecified sub-analysis of the PROTECT (Prevention of Atherosclerosis by SGLT2 Inhibitor: Multicenter, Randomized Controlled Study) trial, which was an investigator-initiated, multicenter, prospective, randomized, open-label, clinical trial primarily designed to evaluate the effect of ipragliflozin treatment administered for 24 months on carotid atherosclerosis in patients with T2DM, we evaluated serial changes in estimated plasma volume (ePV, %) calculated using the Straus formula and estimated extracellular volume (eEV, mL) calculated by the body surface area by 24 months following the initiation of 50-mg ipragliflozin once daily and compared them with those following standard care for T2DM (non-SGLT2 inhibitor use).

RESULTS

This sub-analysis included 464 patients (ipragliflozin, n = 232; control, n = 232), a full analysis set of the PROTECT trial. In an analysis using mixed-effects models for repeated measures, relative to the control group, ipragliflozin significantly reduced ePV by - 10.29% (95% confidence interval [CI]  - 12.47% to - 8.11%; P < 0.001) at 12 months and - 10.76% (95% CI - 12.86% to - 8.67%; P < 0.001) at 24 months. Additionally, ipragliflozin significantly reduced eEV by - 190.44 mL (95% CI - 249.09 to - 131.79 mL; P < 0.001) at 12 months and - 176.90 mL (95% CI  - 233.36 to - 120.44 mL; P < 0.001) at 24 months. The effects of ipragliflozin on these parameters over 24 months were mostly consistent across various patient clinical characteristics.

CONCLUSIONS

This prespecified sub-analysis from the PROTECT trial demonstrated that ipragliflozin treatment, compared with the standard care for T2DM, reduced two types of estimated fluid volume parameters in patients with T2DM, and the effect was maintained for 24 months. Our findings suggest that SGLT2 inhibitor treatment regulates clinical parameters incorporated into the calculating formulas analyzed and consequently fluid volume status for the long-term, and this may be at least partly associated with clinical benefits from chronic use of SGLT2 inhibitors. Trial registration Japan Registry of Clinical Trials, ID jRCT1071220089.

Metabolic Approaches for the Treatment of Dilated Cardiomyopathy

In dilated cardiomyopathy (DCM), where the heart muscle becomes stretched and thin, heart failure (HF) occurs, and the cardiomyocytes suffer from an energetic inefficiency caused by an abnormal cardiac metabolism. Although underappreciated as a potential therapeutic target, the optimal metabolic milieu of a failing heart is still largely unknown and subject to debate. Because glucose naturally has a lower P/O ratio (the ATP yield per oxygen atom), the previous studies using this strategy to increase glucose oxidation have produced some intriguing findings. In reality, the vast majority of small-scale pilot trials using trimetazidine, ranolazine, perhexiline, and etomoxir have demonstrated enhanced left ventricular (LV) function and, in some circumstances, myocardial energetics in chronic ischemic and non-ischemic HF with a reduced ejection fraction (EF). However, for unidentified reasons, none of these drugs has ever been tested in a clinical trial of sufficient size. Other pilot studies came to the conclusion that because the heart in severe dilated cardiomyopathy appears to be metabolically flexible and not limited by oxygen, the current rationale for increasing glucose oxidation as a therapeutic target is contradicted and increasing fatty acid oxidation is supported. As a result, treating metabolic dysfunction in HF may benefit from raising ketone body levels. Interestingly, treatment with sodium-glucose cotransporter-2 inhibitors (SGLT2i) improves cardiac function and outcomes in HF patients with or without type 2 diabetes mellitus (T2DM) through a variety of pleiotropic effects, such as elevated ketone body levels. The improvement in overall cardiac function seen in patients receiving SGLT2i could be explained by this increase, which appears to be a reflection of an adaptive process that optimizes cardiac energy metabolism. This review aims to identify the best metabolic therapeutic approach for DCM patients, to examine the drugs that directly affect cardiac metabolism, and to outline all the potential ancillary metabolic effects of the guideline-directed medical therapy. In addition, a special focus is placed on SGLT2i, which were first studied and prescribed to diabetic patients before being successfully incorporated into the pharmacological arsenal for HF patients.

SGLT2 Inhibitors as Potential Anticancer Agents

Sodium-glucose cotransporter 2 (SGLT2) serves as a critical glucose transporter that has been reported to be overexpressed in cancer models, followed by increased glucose uptake in both mice and humans. Inhibition of its expression can robustly thwart tumor development in vitro and in vivo. SGLT2 inhibitors are a comparatively new class of antidiabetic drugs that have demonstrated anticancer effects in several malignancies, including breast, liver, pancreatic, thyroid, prostate, and lung cancers. This review aims to assess the extent of SGLT involvement in different cancer cell lines and discuss the pharmacology, mechanisms of action, and potential applications of SGLT2 inhibitors to reduce tumorigenesis and its progression. Although these agents display a common mechanism of action, they exhibit distinct affinity towards the SGLT type 2 transporter compared to the SGLT type 1 transporter and varying extents of bioavailability and half-lives. While suppression of glucose uptake has been attributed to their primary mode of antidiabetic action, SGLT2 inhibitors have demonstrated several mechanistic ways to combat cancer, including mitochondrial membrane instability, suppression of β-catenin, and PI3K-Akt pathways, increase in cell cycle arrest and apoptosis, and downregulation of oxidative phosphorylation. Growing evidence and ongoing clinical trials suggest a potential benefit of combination therapy using an SGLT2 inhibitor with the standard chemotherapeutic regimen. Nevertheless, further experimental and clinical evidence is required to characterize the expression and role of SGLTs in different cancer types, the activity of different SGLT subtypes, and their role in tumor development and progression.

Renal Oxygen Demand and Nephron Function: Is Glucose a Friend or Foe?

The kidneys and heart work together to balance the body's circulation, and although their physiology is based on strict inter dependence, their performance fulfills different aims. While the heart can rapidly increase its own oxygen consumption to comply with the wide changes in metabolic demand linked to body function, the kidneys physiology are primarily designed to maintain a stable metabolic rate and have a limited capacity to cope with any steep increase in renal metabolism. In the kidneys, glomerular population filters a large amount of blood and the tubular system has been programmed to reabsorb 99% of filtrate by reabsorbing sodium together with other filtered substances, including all glucose molecules. Glucose reabsorption involves the sodium-glucose cotransporters SGLT2 and SGLT1 on the apical membrane in the proximal tubular section; it also enhances bicarbonate formation so as to preserve the acid-base balance. The complex work of reabsorption in the kidney is the main factor in renal oxygen consumption; analysis of the renal glucose transport in disease states provides a better understanding of the renal physiology changes that occur when clinical conditions alter the neurohormonal response leading to an increase in glomerular filtration pressure. In this circumstance, glomerular hyperfiltration occurs, imposing a higher metabolic demand on kidney physiology and causing progressive renal impairment. Albumin urination is the warning signal of renal engagement over exertion and most frequently heralds heart failure development, regardless of disease etiology. The review analyzes the mechanisms linked to renal oxygen consumption, focusing on sodium-glucose management.

Meta-Inflammation and New Anti-Diabetic Drugs: A New Chance to Knock Down Residual Cardiovascular Risk

Type 2 diabetes mellitus (DM) represents, with its macro and microvascular complications, one of the most critical healthcare issues for the next decades. Remarkably, in the context of regulatory approval trials, sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide 1 receptor agonists (GLP-1 RAs) proved a reduced incidence of major adverse cardiovascular events (MACEs), i.e., cardiovascular death and heart failure (HF) hospitalizations. The cardioprotective abilities of these new anti-diabetic drugs seem to run beyond mere glycemic control, and a growing body of evidence disclosed a wide range of pleiotropic effects. The connection between diabetes and meta-inflammation seems to be the key to understanding how to knock down residual cardiovascular risk, especially in this high-risk population. The aim of this review is to explore the link between meta-inflammation and diabetes, the role of newer glucose-lowering medications in this field, and the possible connection with their unexpected cardiovascular benefits.