Electrocardiographic changes associated with SGLT2 inhibitors and non-SGLT2 inhibitors: A multi-center retrospective study

The potential anti-arrhythmic effect of SGLT2 inhibitors

Sodium-glucose cotransporter type 2 inhibitors (SGLT2i) were initially recommended as oral anti-diabetic drugs to treat type 2 diabetes (T2D), by inhibiting SGLT2 in proximal tubule and reduce renal reabsorption of sodium and glucose. While many clinical trials demonstrated the tremendous potential of SGLT2i for cardiovascular diseases. 2022 AHA/ACC/HFSA guideline first emphasized that SGLT2i were the only drug class that can cover the entire management of heart failure (HF) from prevention to treatment. Subsequently, the antiarrhythmic properties of SGLT2i have also attracted attention. Although there are currently no prospective studies specifically on the anti-arrhythmic effects of SGLT2i. We provide clues from clinical and fundamental researches to identify its antiarrhythmic effects, reviewing the evidences and mechanism for the SGLT2i antiarrhythmic effects and establishing a novel paradigm involving intracellular sodium, metabolism and autophagy to investigate the potential mechanisms of SGLT2i in mitigating arrhythmias.

Impact of baseline ECG characteristics on changes in cardiac biomarkers and echocardiographic metrices after acute myocardial infarction treated with Empagliflozin

The EMMY trial was a multicentre, investigator-initiated, placebo-controlled, double-blind trial, which enrolled 476 patients immediately following AMI and the first study demonstrating a significant reduction in NT-proBNP-levels as well as significant improvements in cardiac structure and function in patients after acute myocardial infarction treated with empagliflozin vs. placebo. However, hardly any data are available investigating the prognostic role of baseline electrocardiogram metrics in SGLT2-inhibitor-treated patients. This post-hoc analysis investigated the association of baseline ECG metrics collected in one centre of the trial (181 patients) with changes in structural and functional cardiac parameters as well as cardiac biomarkers in response to Empagliflozin treatment. A total of 181 patients (146 men; mean age 58 ± 14 years) were included. Median PQ-interval was 156 (IQR 144-174) milliseconds (ms), QRS width 92 (84-98) ms, QTc interval 453 (428-478) ms, Q-wave duration 45 (40-60) ms, Q-wave amplitude 0.40 (0.30-0.70) millivolt (mV), and heart rate was 71 (64-85) bpm. For functional cardiac parameters (LVEF and E/e') of the entire cohort, a greater decrease of E/e' from baseline to week 26 was observed in shorter QRS width (P = 0.005).Structural cardiac endpoints were only found to have a significant positive correlation between LVEDD and Q wave duration (P = 0.037). Higher heart rate was significantly correlated with better response in LVEF (P = 0.001), E/e' (P = 0.021), and NT-proBNP (P = 0.005). Empagliflozin-treatment showed no interaction with the results. Baseline ECG characteristics post AMI are neither predictive for beneficial NTproBNP effects of Empagliflozin post AMI, nor for functional or structural changes within 26 weeks post AMI.

Associations between Oral Glucose-Lowering Agents and Increased Risk for Life-Threatening Arrhythmias in Patients with Type 2 Diabetes Mellitus-A Literature Review

Background and Objectives: The relationship between type 2 diabetes mellitus (T2DM) and cardiovascular (CV) morbidity and mortality is well-established. Ventricular arrhythmias (VA) are frequently diagnosed in patients with T2DM, especially in those with associated coronary syndrome, non-ischemic dilated cardiomyopathy (NIDCM), and heart failure (HF). In these patients, VA and sudden cardiac arrest (SCA) are considered responsible for more than 50% of CV deaths. Newly developed glucose-lowering agents (GLA) seem not only to ameliorate CV morbidity and mortality, but also to reduce the risk of VA and SCA. Materials and Methods: We researched the medical literature on Pub-Med, Clarivate, and Google Scholar for original articles published in the last five years that debated the possible effects of various GLA on ventricular arrhythmias. Results: We identified nineteen original articles, nine of them debating the antiarrhythmic effects of sodium-glucose cotransporter-2 inhibitors (SGLT2i); Conclusions: The results concerning the impact of various GLA on VA/SCA were heterogeneous depending on the pharmacological class studied, with some of them having neutral, positive, or negative effects. Although it appears that SGLT2i reduces the prevalence of atrial fibrillation and SCA, their effect on VA is not conclusive.

Potential favorable action of sodium-glucose cotransporter-2 inhibitors on sudden cardiac death: a brief overview

The primary pharmacological action of sodium-glucose co-transporter 2 (SGLT2) inhibitors is to inhibit the reabsorption of glucose and sodium ions from the proximal tubules of the kidney and to promote urinary glucose excretion. Notably, several clinical trials have recently demonstrated potent protective effects of SGLT2 inhibitors in patients with heart failure (HF) or chronic kidney disease (CKD), regardless of the presence or absence of diabetes. However, the impact of SGLT2 inhibitors on sudden cardiac death (SCD) or fatal ventricular arrhythmias (VAs), the pathophysiology of which is partly similar to that of HF and CKD, remains undetermined. The cardiorenal protective effects of SGLT2 inhibitors have been reported to include hemodynamic improvement, reverse remodeling of the failing heart, amelioration of sympathetic hyperactivity, correction of anemia and impaired iron metabolism, antioxidative effects, correction of serum electrolyte abnormalities, and antifibrotic effects, which may lead to prevent SCD and/or VAs. Recently, as possible direct cardiac effects of SGLT2 inhibitors, not only inhibition of Na⁺/H⁺ exchanger (NHE) activity, but also suppression of late Na⁺ current have been focused on. In addition to the indirect cardioprotective mechanisms of SGLT2 inhibitors, suppression of aberrantly increased late Na⁺ current may contribute to preventing SCD and/or VAs via restoration of the prolonged repolarization phase in the failing heart. This review summarizes the results of previous clinical trials of SGLT2 inhibitors for prevention of SCD, their impact on the indices of electrocardiogram, and the possible molecular mechanisms of their anti-arrhythmic effects.