Fetuin-A and its genetic association with cardiometabolic disease.

Fetuin-A acts as both an inhibitor of calcification and insulin signaling. Previous studies reported conflicting results on the association between fetuin-A and cardiometabolic diseases. We aim to provide further insights into the association between genetically predicted levels of fetuin-A and cardiometabolic diseases using a Mendelian randomization strategy. Genetic variants associated with fetuin-A and their effect sizes were obtained from previous genetic studies. A series of two-sample Mendelian randomization analyses in 412,444 unrelated individuals from the UK Biobank did not show evidence for an association of genetically predicted fetuin-A with any stroke, ischemic stroke, or myocardial infarction. We do find that increased levels of genetically predicted fetuin-A are associated with increased risk of type 2 diabetes (OR = 1.21, 95%CI 1.13-1.30, P = < 0.01). Furthermore, genetically predicted fetuin-A increases the risk of coronary artery disease in individuals with type 2 diabetes, but we did not find evidence for an association between genetically predicted fetuin-A and coronary artery disease in those without type 2 diabetes (P for interaction = 0.03). One SD increase in genetically predicted fetuin-A decreases risk of myocardial infarction in women, but we do not find evidence for an association between genetically predicted fetuin-A and myocardial infarction in men (P for interaction = < 0.01). Genetically predicted fetuin-A is associated with type 2 diabetes. Furthermore, type 2 diabetes status modifies the association of genetically predicted fetuin-A with coronary artery disease, indicating that fetuin-A increases risk in individuals with type 2 diabetes. Finally, higher genetically predicted fetuin-A reduces the risk of myocardial infarction in women, but we do not find evidence for an association between genetically predicted fetuin-A and myocardial infarction in men.

Associations of systemic oxidative stress with functional outcomes after ST-segment elevation myocardial infarction.

BACKGROUND: Ischemia-reperfusion is accompanied by oxidative stress. Serum free thiols (FTs; sulfhydryl groups) reliably reflect systemic oxidative stress. This study evaluates longitudinal changes in FTs and their associations with outcomes after ST-segment elevation myocardial infarction (STEMI). METHODS: FTs were detected in archived serum samples from 378 participants of a neutral randomized trial on metformin therapy after STEMI. FT levels were determined at presentation with STEMI and at 24 h, 2 weeks, 4 months and 1 year thereafter. Outcomes included infarct size and left ventricular ejection fraction (LVEF), both determined with cardiac magnetic resonance imaging after 4 months, and 5-year major adverse cardiovascular events (MACE). RESULTS: Serum FT concentrations at presentation and at 24 h were 356 ± 91 and 353 ± 76 µmol/L, respectively. The change in FTs between presentation and 24 h (ΔFTs) was associated with outcomes in age- and sex-adjusted analysis (per 100 µmol/L FT increase, ß = -0.87 for infarct size, 95% confidence interval (CI): -1.75 to -0.001, P = 0.050; ß = 1.31, 95% CI: 0.37 to 2.25 for LVEF, P = 0.007). Associations between ΔFTs and LVEF were markedly stronger in patients with Thrombolysis in Myocardial Infarction flow of 0 or 1 before percutaneous coronary intervention (PCI)(ß = 2.73, 95% CI: 0.68 to 4.77, P = 0.009). Declining FTs during the first 24 h might be associated with higher incidence of 5-year MACE (P = 0.09). CONCLUSIONS: Changes in oxidative stress early post-PCI may predict functional outcomes after STEMI. Our findings warrant validation in larger cohorts, and then may be used as rationale for development of thiol-targeted therapy in ischemic heart disease.

Predictors of adverse diastolic remodeling in non-diabetic patients presenting with ST-elevation myocardial infarction.

BACKGROUND: Adverse systolic remodeling after ST-elevation myocardial infarction (STEMI) is associated with poor clinical outcomes. However, little is known about diastolic remodeling. The purpose of this study was to identify the factors leading to diastolic remodeling. METHODS: Echocardiography was performed during hospitalization and at 4 months follow-up in 267 non-diabetic STEMI patients from the GIPS-III trial. As parameters of diastolic remodeling we used (1.) the E/e' at 4 months adjusted for the E/e' at hospitalization and (2.) the change in E/e' between hospitalization and 4 months. Multivariable regression models correcting for age and sex were constructed to identify possible association of clinical and angiographic variables as well as biomarkers with diastolic remodeling. RESULTS: Older age, female gender, hypertension, multi vessel disease, higher glucose and higher peak CK were independent predictors of higher E/e' at 4 months in a multivariable model (R2:0.20). After adjustment for E/e' during hospitalization only female gender, multivessel disease and higher glucose remained predictors of E/e' at four months (R2:0.40). Lower myocardial blush grade, AST and NT-proBNP were independent predictors of a higher increase of E/e' between hospitalization and at 4 months in a multivariable model (R2:0.08). CONCLUSIONS: Our data supports the hypothesis that female gender, multivessel coronary artery disease, and microvascular damage are important predictors of adverse diastolic remodeling after STEMI. In addition, our data suggests that older age and hypertension prior to STEMI may have contributed to worse pre-existing diastolic function. TRIAL REGISTRATION: NIH, NCT01217307. Prospectively registered on October 8th 2010, https://clinicaltrials.gov/ct2/show/NCT01217307 .

Agreement of 2D transthoracic echocardiography with cardiovascular magnetic resonance imaging after ST-elevation myocardial infarction.

BACKGROUND: This study was designed to investigate the agreement of 2D transthoracic echocardiography (2D TTE) with cardiovascular magnetic resonance imaging (CMR) in a contemporary population of ST-elevation myocardial infarction (STEMI) patients. METHODS: In this subanalysis of the GIPS-III trial, a randomized controlled trial investigating the administration of metformin in STEMI patients to prevent reperfusion injury, we studied 259 patients who underwent same-day CMR and 2D TTE assessments four months after hospitalization for a first STEMI. Bland-Altman analyses were performed to assess agreement between LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), and LV mass measurements. Sensitivity and specificity of 2D TTE to detect categories of LVEF (≤35%, 35-50%, ≥50%) was determined. Linear regression of absolute differences in measurements between imaging modalities was used to investigate whether patient characteristics impact measurement bias. RESULTS: Pairwise difference (bias) and 95% limits of agreement between CMR and 2D TTE measurements were +84 (37, 147) ml for LVEDV, +39 (6, 85) ml for LVESV, -1.1 ± 13.5% for LVEF, and -75 (-154, -14) g for LV mass. Sensitivity and specificity of 2D TTE to detect subjects with moderately depressed LVEF (35-50%) as measured by CMR were 52% and 88% respectively. We observed a significant effect of enzymatic infarct size on bias between 2D TTE and CMR in measuring LVESV and LVEF (P = 0.029, P = 0.001 respectively), of age and sex on bias between 2D TTE and CMR in measuring LV mass (P = 0.027, P < 0.001) and LVEDV (P = 0.001, P = 0.039), and of heart rate on bias between 2D TTE and CMR in LV volume measurements (P = 0.004, P = 0.016). CONCLUSIONS: Wide limits of agreement, underestimation of LV volumes and overestimation of LV mass was observed when comparing 2D TTE to CMR. Enzymatic infarct size, age, sex, and heart rate are potential sources of bias between imaging modalities.

Plasma interleukin 6 levels are associated with cardiac function after ST-elevation myocardial infarction.

BACKGROUND AND AIMS: Myocardial infarction triggers an inflammatory response involved in cardiac repair. We studied the association of the interleukin 6 (IL-6) cascade with infarct size and cardiac function after ST-elevation myocardial infarction (STEMI). METHODS: In 369 STEMI patients IL-6, soluble IL-6 receptor (sIL-6R), and soluble glycoprotein (sgp) 130 were measured at baseline (hospital admission), 24 h, 2 weeks, 7 weeks, 4 months, and 1 year post-PCI and sIL-6R/IL-6 ratio was calculated. At 4 months, infarct size and left ventricular ejection fraction (LVEF) were assessed by magnetic resonance imaging. Diastolic function (E/e') was determined by echocardiography. RESULTS: Hospital admission levels for IL-6, sIL-6R, sgp 130 were 3.7 pg/ml (IQR 2.1-6.7 pg/ml), 51.6 ng/ml (IQR 37.3-69.0 ng/ml), and 332 ng/ml (IQR 280-399 ng/ml), respectively. 24 h after admission, IL-6 had increased threefold compared to baseline (p < 0.001) and returned below baseline (p < 0.001) 2 weeks after STEMI. sIL-6R and sgp130 levels at 24 h remained similar to baseline but were increased at 2 weeks (p < 0.001; p < 0.001, respectively). IL-6 and sIL-6R/IL-6 ratio at 24 h were independently associated with infarct size [ß 5.4 (95% CI 3.3-7.5); p < 0.001, ß - 4.0 (95% CI - 6.1 to - 1.9); p < 0.001, respectively]. Higher levels of IL-6 at 24 h were associated with lower LVEF [ß - 4.2 (95% CI -6.7 to - 1.8); p = 0.001]. CONCLUSIONS: Higher IL-6 and lower sIL-6R/IL-6 ratio early after presentation with STEMI are indicative for larger infarct size and decreased cardiac function at 4 months.

Left ventricular restoration devices post myocardial infarction.

Even in the era of percutaneous reperfusion therapy, left ventricular (LV) remodeling after myocardial infarction (MI) leading to heart failure remains a major health concern. Contractile dysfunction of the infarcted myocardium results in an increased pressure load, leading to maladaptive reshaping of the LV. Several percutaneous transcatheter procedures have been developed to deliver devices that restore LV shape and function. The purposes of this review are to discuss the spectrum of transcatheter devices that are available or in development for attenuation of adverse LV remodeling and to critically examine the available evidence for improvement of functional status and cardiovascular outcomes.

The Effect of Metformin on Diastolic Function in Patients Presenting with ST-Elevation Myocardial Infarction.

INTRODUCTION: Diastolic dysfunction is an important predictor of poor outcome after myocardial infarction. Metformin treatment improved diastolic function in animal models and patients with diabetes. Whether metformin improves diastolic function in patients presenting with ST-segment elevation myocardial infarction (STEMI) is unknown. METHODS: The GIPS-III trial randomized STEMI patients, without known diabetes, to metformin or placebo initiated directly after PCI. The previously reported primary endpoint was left ventricular ejection fraction at 4 months, which was unaffected by metformin treatment. This is a predefined substudy to determine an effect of metformin on diastolic function. For this substudy trans-thoracic echocardiography was performed during hospitalization and after 4 months. Diastolic dysfunction was defined as having the combination of a functional alteration (i.e. decreased tissue velocity: mean of septal e' and lateral e') and a structural alteration (i.e. increased left atrial volume index (LAVI)). In addition, left ventricular mass index and transmitral flow velocity (E) to mean e' ratio (E/e') were measured to determine an effect of metformin on individual echocardiographic markers of diastolic function. RESULTS: In 237 (63%) patients included in the GIPS-III trial diastolic function was measured during hospitalization as well as at 4 months. Diastolic dysfunction was present in 11 (9%) of patients on metformin and 11 (9%) patients on placebo treatment (P = 0.98) during hospitalization. After 4 months 22 (19%) of patients with metformin and 18 (15%) patients with placebo (P = 0.47) had diastolic dysfunction. In addition, metformin did not improve any of the individual echocardiographic markers of diastolic function. CONCLUSIONS: In contrast to experimental and observational data, our randomized placebo controlled trial did not suggest a beneficial effect of short-term metformin treatment on diastolic function in STEMI patients.