Impact of sodium-glucose co-transporter inhibitors on cardiac autonomic function and mortality: no time to die

Recent Advances and Future Directions in Syncope Management: A Comprehensive Narrative Review

Syncope is a highly prevalent clinical condition characterized by a rapid, complete, and brief loss of consciousness, followed by full recovery caused by cerebral hypoperfusion. This symptom carries significance, as its potential underlying causes may involve the heart, blood pressure, or brain, leading to a spectrum of consequences, from sudden death to compromised quality of life. Various factors contribute to syncope, and adhering to a precise diagnostic pathway can enhance diagnostic accuracy and treatment effectiveness. A standardized initial assessment, risk stratification, and appropriate test identification facilitate determining the underlying cause in the majority of cases. New technologies, including artificial intelligence and smart devices, may have the potential to reshape syncope management into a proactive, personalized, and data-centric model, ultimately enhancing patient outcomes and quality of life. This review addresses key aspects of syncope management, including pathogenesis, current diagnostic testing options, treatments, and considerations in the geriatric population.

Efficacy of Dapagliflozin According to Heart Rate: A Patient-Level Pooled Analysis of DAPA-HF and DELIVER

BACKGROUND

Although elevated resting heart rate (HR) is associated with a higher risk of cardiovascular events in patients with heart failure with reduced ejection fraction in sinus rhythm (SR), the relationship between HR and outcomes among patients with heart failure with mildly reduced ejection fraction/heart failure with preserved ejection fraction and in those with atrial fibrillation (AF) is uncertain. The aims of this study were to examine the association between baseline HR and outcomes across the range of left ventricular ejection fraction, in patients with and without AF, and evaluate the effect of dapagliflozin according to HR.

METHODS

A patient-level pooled analysis of the DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure; heart failure with reduced ejection fraction) and DELIVER (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure trial; heart failure with mildly reduced ejection fraction/heart failure with preserved ejection fraction) trials. The primary outcome of each was the composite of worsening heart failure or cardiovascular death.

RESULTS

Among patients with SR (n=6401, 64%), the rate of the primary outcome was higher in those with higher HR: 16.8 versus 7.7 per 100 person-years for ≥80 bpm versus <60 bpm. The relationship between HR and risk was steeper in heart failure with reduced ejection fraction versus heart failure with mildly reduced ejection fraction/heart failure with preserved ejection fraction. HR was not associated with outcomes in patients in AF for either heart failure phenotype. The benefit of dapagliflozin on the primary outcome was consistent across the HR range in both SR (Pinteraction=0.28) and AF (Pinteraction=0.56), for example, for SR <60 bpm, hazard ratio for dapagliflozin versus placebo 0.72 (95% CI, 0.55-0.95); 60 to 69 bpm, 0.78 (0.63-0.97); 70 to 79 bpm, 0.73 (0.59-0.91); ≥80 bpm, 0.77 (0.61-0.97). The benefit was consistent across HR range in both heart failure with reduced ejection fraction and heart failure with mildly reduced ejection fraction/heart failure with preserved ejection fraction.

CONCLUSIONS

The risk of worsening heart failure or cardiovascular death increased with increasing baseline HR among patients in SR, but this association was not seen among patients in AF, irrespective of left ventricular ejection fraction. The benefit of dapagliflozin was consistent across HR range, irrespective of left ventricular ejection fraction or rhythm.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifiers: NCT03036124 and NCT03619213.

Improving heart failure outcomes with sodium-glucose cotransporter 2 inhibitors in different patient groups

Sodium-glucose cotransporter 2 inhibitors (SGLT-2is) were originally developed for the treatment of hyperglycaemia in type 2 diabetes. Because of regulatory requirements to show the safety of this new class of drugs, a large randomized cardiovascular (CV) outcomes trial was completed but this showed that instead of having a neutral effect on heart failure (HF) outcomes, that these drugs could reduce HF outcomes in this population. Subsequent trials with SGLT-2is have shown that HF hospitalizations are reduced by 30% and CV death or HF hospitalization by 21% in patients with type 2 diabetes. These findings have extended to patients with HF with reduced and mildly reduced or preserved ejection fraction in whom further HF hospitalizations are reduced by 28% and CV death or HF hospitalizations reduced by 23%, and that it is becoming a central therapy for the treatment of HF. Moreover, the benefit in patients with HF is observed regardless of the presence or absence of type 2 diabetes. Similarly, in patients with chronic kidney disease and albuminuria, with and without type 2 diabetes, the benefit of SGLT-2is is clearly seen with a 44% reduction in HF hospitalization and 25% reduction in CV death or HF hospitalization. These trials support the use of SGLT-2is in improving HF outcomes in a broad range of patients, from those with type 2 diabetes, chronic kidney disease and those with pre-existing HF regardless of ejection fraction.

Diabetes-Induced Cardiac Autonomic Neuropathy: Impact on Heart Function and Prognosis

Cardiovascular autonomic neuropathy (CAN) is a severe complication of the advance stage of diabetes. More than 50% of diabetic patients diagnosed with peripheral neuropathy will have CAN, with clinical manifestations including tachycardia, severe orthostatic hypotension, syncope, and physical exercise intolerance. Since the prevalence of diabetes is increasing, a concomitant increase in CAN is expected and will reduce quality of life and increase mortality. Autonomic dysfunction is associated with reduced baroreflex sensitivity and impairment of sympathetic and parasympathetic modulation. Various autonomic function tests are used to diagnose CAN, a condition without adequate treatment. It is important to consider the control of glucose level and blood pressure as key factors for preventing CAN progression. However, altered biomarkers of inflammatory and endothelial function, increased purinergic receptor expression, and exacerbated oxidative stress lead to possible targets for the treatment of CAN. The present review describes the molecular alterations seen in CAN, diagnosis, and possible alternative treatments.

Depot-specific adipose tissue modulation by SGLT2 inhibitors and GLP1 agonists mediates their cardioprotective effects in metabolic disease

Sodium-glucose transporter-2 inhibitors (SGLT-2i) and glucagon-like peptide 1 (GLP-1) receptor agonists are newer antidiabetic drug classes, which were recently shown to decrease cardiovascular (CV) morbidity and mortality in diabetic patients. CV benefits of these drugs could not be directly attributed to their blood glucose lowering capacity possibly implicating a pleotropic effect as a mediator of their impact on cardiovascular disease (CVD). Particularly, preclinical and clinical studies indicate that SGLT-2i(s) and GLP-1 receptor agonists are capable of differentially modulating distinct adipose pools reducing the accumulation of fat in some depots, promoting the healthy expansion of others, and/or enhancing their browning, leading to the suppression of the metabolically induced inflammatory processes. These changes are accompanied with improvements in markers of cardiac structure and injury, coronary and vascular endothelial healing and function, vascular remodeling, as well as reduction of atherogenesis. Here, through a summary of the available evidence, we bring forth our view that the observed CV benefit in response to SGLT-2i or GLP-1 agonists therapy might be driven by their ameliorative impact on adipose tissue inflammation.

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

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