Sodium-glucose cotransporter 2 inhibitors in patients with heart failure: a systematic review and meta-analysis of randomized trials

Sodium-Glucose Transporter 2 Inhibitors in Heart Failure: An Overview of Systematic Reviews

Background: Several studies have shown that sodium-dependent glucose transporter 2 inhibitors can be used in the treatment of heart failure. This article summarized systematic reviews of sodium-dependent glucose transporter 2 inhibitors in the treatment of heart failure in order to evaluate efficacy and safety. Methods: We systematically searched eight electronic databases from inception to July 2023. We used Assessment of Multiple Systematic Reviews 2 to evaluate the methodological quality, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 to assess report quality, Risk of Bias in Systematic Review to assess the risk of bias, and Grading of Recommendations Assessment, Development, and Evaluation to rate the quality of evidence. Outcome: A total of 36 systematic reviews were included. Our results were classified as clear evidence of benefit: hospitalization for heart failure; possible benefit: cardiovascular death (mortality) and renal outcome composite; clear evidence of no effect or equivalence: atrial arrhythmias, ventricular arrhythmia, atrial fibrillation, and hypotension; possible harm: genital infection; insufficient evidence to draw a conclusion: atrial flutter, major adverse cardiovascular events, urinary tract infection, acute kidney injury, hypoglycemia, and bone fracture. Conclusions: Sodium-dependent glucose transporter 2 inhibitors are beneficial for the treatment of heart failure, especially in terms of heart failure hospitalization.

Hypoglycemic Drugs in Patients with Diabetes Mellitus and Heart Failure: A Narrative Review

Over the last few years, given the increase in the incidence and prevalence of both type 2 diabetes mellitus (T2DM) and heart failure (HF), it became crucial to develop guidelines for the optimal preventive and treatment strategies for individuals facing these coexisting conditions. In patients aged over 65, HF hospitalization stands out as the predominant reason for hospital admissions, with their prognosis being associated with the presence or absence of T2DM. Historically, certain classes of glucose-lowering drugs, such as thiazolidinediones (rosiglitazone), raised concerns due to an observed increased risk of myocardial infarction (MI) and cardiovascular (CV)-related mortality. In response to these concerns, regulatory agencies started requiring CV outcome trials for all novel antidiabetic agents [i.e., dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors), glucagon-like peptide-1 receptor agonists (GLP-1 RAs), and sodium-glucose cotransporter-2 inhibitors (SGLT2is)] with the aim to assess the CV safety of these drugs beyond glycemic control. This narrative review aims to address the current knowledge about the impact of glucose-lowering agents used in T2DM on HF prevention, prognosis, and outcome.

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.

Efficacy and safety of sodium-glucose cotransporter-2 inhibitors in heart failure with mildly reduced or preserved ejection fraction: an overview of 36 systematic reviews

The recently published randomized trials (RCTs) evaluating the effect of Sodium-glucose cotransporter-2 inhibitors (SGLT2i) in heart failure with mildly reduced (HFmrEF) or preserved ejection fraction (HFpEF) led researchers to perform a plethora of systematic reviews (SRs), often providing contradictory conclusions. This overview of reviews was aimed at summarizing the evidence of these SRs, quantifying the overlap, re-analyzing the evidence in case new studies that were identified, and mapping knowledge gaps. Literature search was conducted through Medline, Scopus, and Cochrane until March 22, 2023. Overall, 36 SRs synthesizing results from 18 RCTs were identified. A substantial overlap was identified among the SRs synthesizing large heart failure or cardiovascular outcome trials (CVOTs). Regarding the composite outcome of cardiovascular (CV) mortality or hospitalization for heart failure (HHF), all authors reported a significant favorable effect. A beneficial effect was also noted for CV and all-cause mortality, albeit not significant. Our meta-analysis demonstrated a significant improvement in health-related quality-of-life (HRQoL) as assessed by the Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OSS, MD = 1.97, p < 0.001), Total Symptom Score (KCCQ-TSS, MD = 2.29, p < 0.001), Clinical Summary Score (KCCQ-CSS, MD = 1.59, p < 0.001), and the 6-min walking distance (MD = 10.78 m, p = 0.032). Regarding safety, SGLT2i were associated with a significantly lower risk of serious adverse events compared to placebo (RR = 0.94, p = 0.002). The use of SGLT2i in HFpEF is both efficient and safe. Further research is required to clarify the impact of SGTL2i on different subphenotypes of HFpEF and the cardiorespiratory capacity of these patients.

Five-Year Follow-up after Transcatheter Repair of Secondary Mitral Regurgitation

BACKGROUND

Data from a 5-year follow-up of outcomes after transcatheter edge-to-edge repair of severe mitral regurgitation, as compared with outcomes after maximal doses of guideline-directed medical therapy alone, in patients with heart failure are now available.

METHODS

We randomly assigned patients with heart failure and moderate-to-severe or severe secondary mitral regurgitation who remained symptomatic despite the use of maximal doses of guideline-directed medical therapy to undergo transcatheter edge-to-edge repair plus receive medical therapy (device group) or to receive medical therapy alone (control group) at 78 sites in the United States and Canada. The primary effectiveness end point was all hospitalizations for heart failure through 2 years of follow-up. The annualized rate of all hospitalizations for heart failure, all-cause mortality, the risk of death or hospitalization for heart failure, and safety, among other outcomes, were assessed through 5 years.

RESULTS

Of the 614 patients enrolled in the trial, 302 were assigned to the device group and 312 to the control group. The annualized rate of hospitalization for heart failure through 5 years was 33.1% per year in the device group and 57.2% per year in the control group (hazard ratio, 0.53; 95% confidence interval [CI], 0.41 to 0.68). All-cause mortality through 5 years was 57.3% in the device group and 67.2% in the control group (hazard ratio, 0.72; 95% CI, 0.58 to 0.89). Death or hospitalization for heart failure within 5 years occurred in 73.6% of the patients in the device group and in 91.5% of those in the control group (hazard ratio, 0.53; 95% CI, 0.44 to 0.64). Device-specific safety events within 5 years occurred in 4 of 293 treated patients (1.4%), with all the events occurring within 30 days after the procedure.

CONCLUSIONS

Among patients with heart failure and moderate-to-severe or severe secondary mitral regurgitation who remained symptomatic despite guideline-directed medical therapy, transcatheter edge-to-edge repair of the mitral valve was safe and led to a lower rate of hospitalization for heart failure and lower all-cause mortality through 5 years of follow-up than medical therapy alone. (Funded by Abbott; COAPT ClinicalTrials.gov number, NCT01626079.).

Is it time for class I recommendation for sodium-glucose cotransporter-2 inhibitors in heart failure with mildly reduced or preserved ejection fraction?: An updated systematic review and meta-analysis

Background

In heart failure with reduced ejection fraction (HFrEF), sodium-glucose cotransporter-2 (SGLT2) inhibitors were demonstrated to lower cardiovascular mortality (CV death) and hospitalization for heart failure (HHF); however, the advantages of SGLT2 inhibitors in heart failure with mildly reduced (HFmrEF) or preserved ejection fraction (HFpEF) are less clear. SGLT2 inhibitors were reported to enhance quality of life (QoL) in HFmrEF or HFpEF patients; however, the findings among studies are inconsistent.

Objective

To conduct an updated systematic review and meta-analysis of recent data to assess the effect of SGLT2 inhibitors on cardiovascular outcomes and QoL in patients with HFmrEF or HFpEF.

Method

Three databases were searched for studies that evaluated SGLT2 inhibitors and their effect on cardiovascular outcomes, including CV death, HHF, all-cause death, and the composite outcome of CV death, HHF, and urgent visit for heart failure (HF), and patient QoL (Kansas City Cardiomyopathy Questionnaire [KCCQ] score compared to baseline, and increase in KCCQ score ≥ 5 points) that were published during January 2000-August 2022. The meta-analysis was performed using the inverse variance method and random-effects model. INPLASY registration: INPLASY202290023.

Results

Sixteen studies (9 recent RCTs) were included, and a total of 16,710 HFmrEF or HFpEF patients were enrolled. SGLT2 inhibitors significantly reduced composite cardiovascular outcome (CV death/HHF/urgent visit for HF; pooled hazard ratio [HR]: 0.80, 95% confidence interval [95%CI]: 0.74-0.86) and HHF alone (HR: 0.74, 95%CI: 0.67-0.82), but there was no significant reduction in CV death alone (HR: 0.93, 95%CI: 0.82-1.05). Benefit of SGLT2 inhibitors for decreasing CV death/HHF was observed across all subgroups, including left ventricular ejection fraction (LVEF) range, diabetes status, New York Heart Association functional class, and baseline renal function. For total HHF, SGLT2 inhibitors conferred benefit in both LVEF 50-60% (HR: 0.64, 95%CI: 0.54-0.76), and LVEF >60% (HR: 0.84, 95%CI: 0.71-0.98). Significant change was observed in the KCCQ-clinical summary score compared to baseline (mean difference: 1.33, 95%CI: 1.31-1.35), and meaningful improvement in QoL was shown across all 3 types of increase in KCCQ score ≥ 5 points.

Conclusion

This study demonstrates the benefits of SGLT2 inhibitors for improving cardiovascular outcomes and QoL in HFmrEF or HFpEF patients.

The Therapeutic Role of SGLT-2 Inhibitors in Acute Heart Failure: From Pathophysiologic Mechanisms to Clinical Evidence with Pooled Analysis of Relevant Studies across Safety and Efficacy Endpoints of Interest

(1) Background: Sodium-glucose co-transporter-2 (SGLT-2) inhibitors constitute a novel drug class with remarkable cardiovascular benefits for patients with chronic heart failure (HF). Recently, this class has been utilized in acute HF as an additional treatment option to classic diuretics, which remain the cornerstone of treatment. (2) Methods: We attempted to identify those pathophysiologic mechanisms targeted by SGLT-2 inhibitors, which could be of benefit to patients with acute HF. We then conducted a comprehensive review of the literature within the PubMed database in order to identify relevant studies, both randomized controlled trials (RCTs) and observational studies, assessing the safety and efficacy of SGLT-2 inhibitors in acute HF. (3) Results: SGLT-2 inhibitors induce significant osmotic diuresis and natriuresis, decrease interstitial fluid volume and blood pressure, improve left ventricular (LV) function, ameliorate LV remodeling and prevent atrial arrhythmia occurrence, mechanisms that seem to be beneficial in acute HF. However, currently available studies, including six RCTs and two real-world studies, provide conflicting results concerning the true efficacy of SGLT-2 inhibitors, including "hard" surrogate endpoints. (4) Conclusions: Current evidence appears insufficient to substantiate the use of SGLT-2 inhibitors in acute HF. Further trials are required to shed more light on this issue.

Promise of sodium-glucose co-transporter-2 inhibitors in heart failure with mildly reduced ejection fraction

Heart failure with mildly reduced ejection fraction (HFmrEF) is associated with comparable poor outcomes as other subtypes of heart failure and remains a medical unmet need due to the paucity of effective therapies. According to large cardiovascular (CV) outcome trials in patients with heart failure, sodium–glucose co‐transporter‐2 inhibitors (SGLT2is) reduce CV mortality and hospitalizations for heart failure in patients with heart failure across the spectrum of left ventricular ejection fraction (LVEF). There has been a lack of dedicated trials in HFmrEF. However, several large outcome trials in heart failure that enrolled patients with HFmrEF could provide a hint on the role of SGLT2is in this subgroup. This review focuses on CV effects of three major SGLT2is—dapagliflozin, empagliflozin, and sotagliflozin—in patients with HFmrEF. A narrative review of trials investigating the efficacy of each medication in treating heart failure with LVEF > 40% is provided with a focus on their LVEF subgroup analyses. The purpose of this review is to discuss the current state of evidence regarding the potential of SGLT2is in HFmrEF management. Current limited evidence suggests that SGLT2is might be a favourable treatment modality for patients with HFmrEF to reduce hospitalization for heart failure and CV mortality. This conclusion needs to be further supported by clear HFmrEF subgroup analysis of the existing trials. Further outcome trials involving sufficient patients with different subtypes of HFmrEF are needed to confirm and assess CV benefits of SGLT2is in HFmrEF. Possible mechanisms by which SGLT2is exert their cardioprotective effect are also described briefly.