Effect of empagliflozin on left ventricular contractility and peak oxygen uptake in subjects with type 2 diabetes without heart disease: results of the EMPA-HEART trial.

BACKGROUND: The mechanism through which sodium-glucose cotransporter 2 inhibitors (SGLT2i) prevent the incidence of heart failure and/or affect cardiac structure and function remains unclear. METHODS: The EMPA-HEART trial is aimed at verifying whether empagliflozin improves myocardial contractility (left ventricle global longitudinal strain, LV-GLS) and/or cardiopulmonary fitness (peak oxygen uptake, VO2peak) in subjects with type 2 diabetes (T2D) without heart disease. Patients with T2D, normal LV systolic function (2D-Echo EF > 50%), and no heart disease were randomized to either empagliflozin 10 mg or sitagliptin 100 mg for 6 months and underwent repeated cardiopulmonary exercise tests with echocardiography and determination of plasma biomarkers. RESULTS: Forty-four patients completed the study, 22 per arm. Despite comparable glycaemic control, modest reductions in body weight (- 1.6; [- 2.7/- 0.5] kg, p = 0.03) and plasma uric acid (- 1.5; [- 2.3/- 0.6], p = 0.002), as well as an increase in haemoglobin (+ 0.7; [+ 0.2/+ 1.1] g/dL, p = 0.0003) were evident with empagliflozin. No difference was detectable in either LV-GLS at 1 month (empagliflozin vs sitagliptin: + 0.44; [- 0.10/+ 0.98]%, p = 0.11) and 6 months of therapy (+ 0.53; [- 0.56/+ 1.62]%), or in VO2peak (+ 0.43; [- 1.4/+ 2.3] mL/min/kg, p = 0.65). With empagliflozin, the subgroup with baseline LV-GLS below the median experienced a greater increase (time*drug p < 0.05) in LV-GLS at 1 month (+ 1.22; [+ 0.31/+ 2.13]%) and 6 months (+ 2.05; [+ 1.14/+ 2.96]%), while sitagliptin induced a modest improvement in LV-GLS only at 6 months (+ 0.92; [+ 0.21/+ 0.62]%). CONCLUSIONS: Empagliflozin has neutral impact on both LV-GLS and exercise tolerance in subjects with T2D and normal left ventricular function. However, in patients with subclinical dysfunction (LV-GLS < 16.5%) it produces a rapid and sustained amelioration of LV contractility. Trial registration EUDRACT Code 2016-002225-10.

Plaque characteristics and biomarkers predicting regression and progression of carotid atherosclerosis.

The factors that influence the atherosclerotic disease process in high-risk individuals remain poorly understood. Here, we used a combination of vascular imaging, risk factor assessment, and biomarkers to identify factors associated with 3-year change in carotid disease severity in a cohort of high-risk subjects treated with preventive therapy (n = 865). The results show that changes in intima-media thickness (IMT) are most pronounced in the carotid bulb. Progression of bulb IMT demonstrates independent associations with baseline bulb IMT, the plaque gray scale median (GSM), and the plasma level of platelet-derived growth factor (PDGF) (standardized ß-coefficients and 95% confidence interval [CI] -0.14 [-0.06 to -0.02] p = 0.001, 0.15 [0.02-0.07] p = 0.001, and 0.20 [0.03-0.07] p < 0.001, respectively). Plasma PDGF correlates with the plaque GSM (0.23 [0.15-0.29] p < 0.001). These observations provide insight into the atherosclerotic process in high-risk subjects by showing that progression primarily occurs in fibrotic plaques and is associated with increased levels of PDGF.

Use of Vascular Assessments and Novel Biomarkers to Predict Cardiovascular Events in Type 2 Diabetes: The SUMMIT VIP Study.

OBJECTIVE: Cardiovascular disease (CVD) risk prediction represents an increasing clinical challenge in the treatment of diabetes. We used a panel of vascular imaging, functional assessments, and biomarkers reflecting different disease mechanisms to identify clinically useful markers of risk for cardiovascular (CV) events in subjects with type 2 diabetes (T2D) with or without manifest CVD. RESEARCH DESIGN AND METHODS: The study cohort consisted of 936 subjects with T2D recruited at four European centers. Carotid intima-media thickness and plaque area, ankle-brachial pressure index, arterial stiffness, endothelial function, and circulating biomarkers were analyzed at baseline, and CV events were monitored during a 3-year follow-up period. RESULTS: The CV event rate in subjects with T2D was higher in those with (n = 440) than in those without (n = 496) manifest CVD at baseline (5.53 vs. 2.15/100 life-years, P < 0.0001). New CV events in subjects with T2D with manifest CVD were associated with higher baseline levels of inflammatory biomarkers (interleukin 6, chemokine ligand 3, pentraxin 3, and hs-CRP) and endothelial mitogens (hepatocyte growth factor and vascular endothelial growth factor A), whereas CV events in subjects with T2D without manifest CVD were associated with more severe baseline atherosclerosis (median carotid plaque area 30.4 mm2 [16.1-92.2] vs. 19.5 mm2 [9.5-40.5], P = 0.01). Conventional risk factors, as well as measurements of arterial stiffness and endothelial reactivity, were not associated with CV events. CONCLUSIONS: Our observations demonstrate that markers of inflammation and endothelial stress reflect CV risk in subjects with T2D with manifest CVD, whereas the risk for CV events in subjects with T2D without manifest CVD is primarily related to the severity of atherosclerosis.

Association between renin and atherosclerotic burden in subjects with and without type 2 diabetes.

BACKGROUND: Activation of the renin-angiotensin-aldosterone-system (RAAS) has been proposed to contribute to development of vascular complications in type 2 diabetes (T2D). The aim of the present study was to determine if plasma renin levels are associated with the severity of vascular changes in subjects with and without T2D. METHODS: Renin was analyzed by the Proximity Extension Assay in subjects with (n = 985) and without (n = 515) T2D participating in the SUMMIT (SUrrogate markers for Micro- and Macro-vascular hard endpoints for Innovative diabetes Tools) study and in 205 carotid endarterectomy patients. Vascular changes were assessed by determining ankle-brachial pressure index (ABPI), carotid intima-media thickness (IMT), carotid plaque area, pulse wave velocity (PWV) and the reactivity hyperemia index (RHI). RESULTS: Plasma renin was elevated in subjects with T2D and demonstrated risk factor-independent association with prevalent cardiovascular disease both in subjects with and without T2D. Renin levels increased with age, body mass index, HbA1c and correlated inversely with HDL. Subjects with T2D had more severe carotid disease, increased arterial stiffness, and impaired endothelial function. Risk factor-independent associations between renin and APBI, bulb IMT, carotid plaque area were observed in both T2D and non-T2D subjects. These associations were independent of treatment with RAAS inhibitors. Only weak associations existed between plasma renin and the expression of pro-inflammatory and fibrous components in plaques from 205 endarterectomy patients. CONCLUSIONS: Our findings provide clinical evidence for associations between systemic RAAS activation and atherosclerotic burden and suggest that this association is of particular importance in T2D.

Clinical Phenotype and Microvascular Dynamics of Subjects with Endothelial Dysfunction as Assessed by Peripheral Tonometry.

OBJECTIVE: To evaluate the characteristics and the determinants of ED, as measured by PAT. METHODS: We measured basal and post-ischemic digital pulse amplitude (EndoPAT(®)) in a mixed outpatient population of 206 diabetic and 101 non-diabetic subjects, of whom 50% with clinically manifest CVD, undergoing to an extensive clinical, biochemical, and vascular phenotype characterization. RESULTS: The major characteristics of ED (tertile 1 vs 3), in addition to lower post-ischemic vasodilatory reserve (34 vs 203%), were a 3-fold higher baseline pulse amplitude and a delayed (60 second) peak response. The main determinant of this response was the baseline pulse amplitude (Stß = -0.59), which in turn was influenced by age (Stß = 0.13), central obesity (Stß = 0.27) and inversely by HDL cholesterol (Stß = -0.17), and systolic blood pressure (Stß = -0.19). No association was observed with cardiovascular risk factors, previous cardiovascular event or extent of atherosclerosis (ABI and IMT, PWV). Most of the variability in baseline pulse amplitude remained unexplained (r(2) = 0.14). CONCLUSIONS: ED, as detected by PAT in a population enriched with subjects at risk for CVD neither reflects the burden of classical risk factors (under treatment) nor the severity of atherosclerosis. Aside from central obesity and HDL cholesterol, most of the factors responsible for this ED remain unknown.