Stress hyperglycemia in acute ST-segment elevation myocardial infarction is a marker of left ventricular remodeling

Targeted Antioxidant Therapy Reduces Hyperglycemic Exacerbation of Myocardial Ischemia/Reperfusion Injury

INTRODUCTION

Acute hyperglycemia (HG) enhances inflammatory and oxidative stress and exacerbates myocardial infarct size during ischemia-reperfusion injury by activating splenic leukocytes. Formyl peptide receptor 1 (FPR1) on leukocytes is activated by and mediates myocardial ischemia-reperfusion injury. We hypothesize that selective FPR1 antagonist cinnamoyl-F-(D)L-F-(D)L-F (CF) or potent reducing agent tris (2-carboxyethyl) phosphine hydrochloride (TCEP) could abrogate hyperglycemic infarct exacerbation, both alone and synergistically via a novel CF-TCEP compound that would target leukocytes for antioxidative effect.

METHODS

Acute HG was induced in wild type mice with an intraperitoneal dextrose injection followed by left coronary artery occlusion (30 min) and reperfusion (60 min). In treatment groups, CF (0.1 mg/kg or 1 mg/kg), TCEP (1 mg/kg or 20 mg/kg), or the CF-TCEP conjugate (0.1 mg/kg) was administered intravenously before reperfusion. The hearts were harvested to measure infarct size (IF).

RESULTS

HG resulted in >50% increase in IF compared to euglycemic mice (52.1 ± 3.0 versus 34.0 ± 3.2%, P < 0.05). Neither CF nor TCEP independently exerted an infarct-sparing effect at lower doses (46.2 ± 2.1% or 50.9 ± 4.1%, P > 0.05 versus HG control) but at high doses, significantly attenuated IF exacerbation (23.2 ± 5.2% or 33.9 ± 3.6%, P < 0.05 versus HG control). However, the low-dose CF-TCEP conjugate significantly reduced IF (39.1 ± 1.7%, P < 0.05 versus HG control). IF was decreased to near euglycemic control levels (P > 0.05).

CONCLUSIONS

The CF-TECP conjugate synergistically attenuated HG infarct exacerbation at significantly lower respective doses of CF and TCEP. In addition to the intrinsic anti-inflammatory effect of blocking FPR1, CF is also a feasible tool for leukocyte-targeted therapy to treat IRI.

Elevated stress hyperglycemia and the presence of intracranial artery stenosis increase the risk of recurrent stroke

BACKGROUND

Stress hyperglycemia has served as a reliable biomarker to predict poor outcomes after ischemic stroke. However, recent studies have reported some contrary conclusions. Different stroke subtypes may respond inconsistently to stress hyperglycemia. The progression of intracranial atherosclerotic stenosis (ICAS) is tightly related to hyperglycemia. Thus, this study aims to determine the relationship between stress hyperglycemia and recurrent stroke in ischemic stroke patients with or without intracranial atherosclerotic stenosis.

METHODS

This is a multicenter retrospective observational cohort study. Patients with acute minor ischemic stroke and eligible computed tomography and magnetic resonance imaging data were enrolled. The severity of stress hyperglycemia is measured by the stress hyperglycemia ratio (SHR). SHR was calculated based on fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) levels. The primary outcome was stroke recurrence during hospitalization. The interaction of SHR levels with the presence of ICAS on the primary outcome was investigated using univariable and multivariable Cox proportional hazards models. Restricted cubic splines were applied to determine the nonlinear relationship between SHR and primary outcome. A two-piecewise linear regression model was used to identify the threshold of SHR.

RESULTS

A total of 610 participants were included in the study. The average age of the patients was 61.4 ± 12.9 years old, and approximately 70% of participants were males. A total of 189 (30.98%) patients had ICAS. The patients were categorized into 3 groups based on the tertiles of SHR. Compared with the group with a lower SHR, a higher SHR was significantly associated with the risk of stroke recurrence in the ICAS group (hazard ratio [HR], 8.52, 95% confidence interval [CI], 3.16-22.96, P<0.001). When SHR was treated as a continuous variable, each 0.1-unit increase in SHR in the ICAS group was associated with a 1.63-fold increase in the risk of recurrence (HR, 1.63, 95% CI, 1.39-1.9, P<0.001) with a threshold of 0.75. FPG but not HbA1c was associated with stroke recurrence in ICAS patients (HR, 1.17, 95% CI, 1.08-1.26, P<0.001). Sensitive analyses showed consistent results after adjusting for previous diabetes mellitus, oral hypoglycemic agents and insulin injection.

CONCLUSIONS

SHR represents a better biomarker to predict the risk of stroke recurrence in patients with ICAS than FPG and HbA1c regardless of previous diabetes mellitus.

TRIAL REGISTRATION

https://www.chictr.org.cn/showproj.aspx?proj=125817; Identifier, [ChiCTR2100046958].

Association of Stress hyperglycemia and adverse cardiac events in acute myocardial infarction - A cohort study

BACKGROUND

Stress hyperglycemia is a common phenomenon in patients presenting with acute myocardial infarction (MI). We aim to evaluate the association of stress hyperglycemia at the time of hospital presentation and adverse cardiac events in myocardial infarction during the course of hospital stay.

METHODS

Subjects with age ≥18 years with acute MI were recruited on hospital admission and categorized based on admission blood glucose (<180 and ≥180 mg/dl, 50 patients in each group). Both groups were compared for clinical outcomes, adverse cardiac events and mortality. We also compared the adverse cardiac outcomes based on HbA1c levels (<6% and ≥6%).

RESULTS

Patients with high blood glucose on admission (stress hyperglycemia) had significant increased incidences of severe heart failure (Killip class 3 and 4), arrythmias, cardiogenic shock and mortality (p value = 0.001, 0.004, 0.044, and 0.008 respectively). There was no significant association between adverse cardiac events and HbA1c levels (heart failure 18.8% vs. 25%, p value = 0.609 and mortality 16.7% vs. 17.3%, p value = 0.856).

CONCLUSIONS

Stress hyperglycemia is significantly associated with adverse clinical outcomes in patients with MI irrespective of previous diabetic history or glycemic control. Clinicians should be vigilant for admission blood glucose while treating MI patients.

Pulsed ultrasound attenuates the hyperglycemic exacerbation of myocardial ischemia-reperfusion injury

OBJECTIVE

Acute hyperglycemia during myocardial infarction worsens outcomes in part by inflammatory mechanisms. Pulsed ultrasound has anti-inflammatory potential in bone healing and neuromodulation. We hypothesized that pulsed ultrasound would attenuate the hyperglycemic exacerbation of myocardial ischemia-reperfusion injury via the cholinergic anti-inflammatory pathway.

METHODS

Acute hyperglycemia was induced in wild-type C57BL6 or acetylcholine-receptor knockout (α7nAChR-/-) mice by intraperitoneal injection of glucose. Pulsed ultrasound (frequency 7 MHz, bursting mechanical index 1.2, duration 1 second, repeated every 6 seconds for 2 minutes, 20-second total exposure) was performed at the spleen or neck after glucose injection. Separate mice underwent vagotomy before treatment. The left coronary artery was occluded for 20 minutes, followed by 60 minutes of reperfusion. The primary end point was infarct size in explanted hearts.

RESULTS

Splenic pulsed ultrasound significantly decreased infarct size in wild-type C57BL6 mice exposed to acute hyperglycemia and myocardial ischemia-reperfusion injury (5.2% ± 4.4% vs 16.9% ± 12.5% of risk region, P = .013). Knockout of α7nAChR abrogated the beneficial effect of splenic pulsed ultrasound (22.2% ± 12.1%, P = .79 vs control). Neck pulsed ultrasound attenuated the hyperglycemic exacerbation of myocardial infarct size (3.5% ± 4.8%, P = .004 vs control); however, the cardioprotective effect disappeared in mice that underwent vagotomy. Plasma acetylcholine, β2 adrenergic receptor, and phosphorylated Akt levels were increased after splenic pulsed ultrasound treatment.

CONCLUSIONS

Pulsed ultrasound treatment of the spleen or neck attenuated the hyperglycemic exacerbation of myocardial ischemia-reperfusion injury leading to a 3-fold decrease in infarct size. Pulsed ultrasound may provide cardioprotection via the cholinergic anti-inflammatory pathway and could be a promising new nonpharmacologic, noninvasive therapy to reduce infarct size during acute myocardial infarction and improve patient outcomes.

Insulin resistance and dysglycemia are associated with left ventricular remodeling after myocardial infarction in non-diabetic patients

Background

Adverse cardiac remodeling after ST-segment elevation myocardial infarction (STEMI) is a major cause for poor cardiovascular outcomes such as heart failure. The predisposing factors and underlying mechanisms remain not fully understood. This study investigates the association of insulin resistance and dysglycemia with left ventricular (LV) remodeling after STEMI in non-diabetic patients.

Methods

A total of 485 non-diabetic subjects with STEMI who underwent primary percutaneous coronary intervention were consecutively enrolled and followed up for 12 months. Relation of homeostasis model assessment-estimated insulin resistance (HOMA-IR) and glucose levels to changes in echocardiography parameters was studied.

Results

Left ventricular dilation was detected in 49.1% of subjects at 12-month follow-up after STEMI, and was more severe in subjects with impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and high HOMA-IR levels. HOMA-IR remained correlated to changes in LV dimensions after adjusting for confounding risk factors. Multivariate regression analysis demonstrated that higher HOMA-IR was independently associated with greater LV dilation after STEMI. A significant interaction term was present between HOMA-IR and IGT in the model (P = 0.001).

Conclusions

Our study reveals that insulin resistance and dysglycemia are prevalent in non-diabetic patients with STEMI and are predictors of the post-infarction LV dilation.

Trial registration Trials number, NCT02089360; registered on March 17, 2014

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0904-3) contains supplementary material, which is available to authorized users.

Metabolomic Approach in STEMI-Patients Undergoing Left Ventricular Remodeling

Left ventricular remodeling (LVR) occurring after ST-segment elevation myocardial infarction (STEMI) is frequent and severe. We present a metabolomic approach as an attempt to reveal unknown biomarkers associated with post-STEMI LVR. Out of 192 consecutive patients with successfully revascularized STEMI, 32 presented LVR and were clinically matched with 32 no-LVR patients. They underwent cardiac magnetic resonance at baseline, three months and 12 months. Blood samples were collected during index hospitalization. Creatine kinase (CK) peak and inflammatory markers were higher for LVR patients compared to no-LVR patients (mean 3466 ± 2211 and 2394 ± 1615 UI/L respectively, p = 0.005 for CK peak; mean 35.9 ± 44.3 vs. 21.7 ± 30.4 mg/L respectively, p = 0.020 for C-reactive protein). Leukocyte and neutrophil counts were also higher for LVR patients (mean 12028 ± 2593/mL vs. 10346 ± 3626/mL respectively, p = 0.028 and mean 9035 ± 3036/mL vs. 7596 ± 3822/mL respectively, p < 0.001). For metabolomic analysis, sphingomyelin C20:2 and symmetrical dimethylarginine were higher for LVR patients, but did not reach significance after the correction for the alpha risk. The metabolomic approach did not discriminate patients with and without LVR. However, common parameters that focus on infarction severity, such as infarct size and inflammatory markers, differed between the groups.

Impact of acute diabetes decompensation on outcomes of diabetic patients admitted with ST-elevation myocardial infarction

BACKGROUND

Acute hyperglycemia is associated with worse outcomes in diabetic patients admitted with ST-elevation myocardial infarction (STEMI). However, the impact of full-scale decompensated diabetes on STEMI outcomes has not been investigated.

METHODS

We utilized the national inpatient sample (2003-2014) to identify adult diabetic patients admitted with STEMI. We defined decompensated diabetes as the presence of diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar state (HHS). We compared in-hospital morbidity and mortality and cost between patients with and without diabetes decompensation before and after propensity-score matching.

RESULTS

A total of 73,722 diabetic patients admitted with STEMI were included in the study. Of those, 1131 (1.5%) suffered DKA or HSS during the hospitalization. After propensity-score matching, DKA/HHS remained associated with a significant 32% increase in in-hospital mortality (25.6% vs. 19.4%, p = 0.001). The DKA/HHS group also had higher incidences of acute kidney injury (39.4% vs. 18.9%, p < 0.001), sepsis (7.3% vs. 4.9%, p = 0.022), blood transfusion (11.3% vs. 8.2%) and a non-significant trend towards higher incidence of stroke (3.8% vs. 2.4%, p = 0.087). Also, DKA/HHS diagnosis was associated with lower rates of referral to coronary angiography (51.5% vs. 55.5%, p = 0.023), coronary stenting (26.1% vs. 34.8%, p < 0.001), or bypass grafting (6.2% vs. 8.7%, p = 0.033). Referral for invasive angiography was associated with lower odds of death during the hospitalization (adjusted OR 0.66, 95%CI 0.44-0.98, p = 0.039).

CONCLUSIONS

Decompensated diabetes complicates ~ 1.5% of STEMI admissions in diabetic patients. It is associated with lower rates of referral for angiography and revascularization, and a negative differential impact on in-hospital morbidity and mortality and cost.

Admission plasma glucose levels within the normal to mildly impaired range and the outcome of patients with acute coronary syndrome

BACKGROUND

Elevated admission plasma glucose levels >140 mg/dl are associated with adverse clinical outcomes in both diabetic and non-diabetic patients admitted with acute coronary syndrome (ACS). We aimed to evaluate the association between admission plasma glucose levels <140 mg/dl and the outcome of non-diabetic patients admitted with acute coronary syndrome.

METHODS

The study population consisted of patients with acute coronary syndrome included in the Acute Coronary Syndrome Israeli Survey during 2000-2013. Diabetic patients were excluded. The primary endpoint was all-cause mortality at one year.

RESULTS

The 452 0 patients had a mean age of 61.7±13.5 years and were stratified into four quartiles according to admission plasma glucose (60-94, 95-105, 106-119, 120-140 mg/dl). Patients with higher admission plasma glucose were older and included a higher percentage of smokers. In addition, the higher the glucose so also did they have a poorer risk factor profile including a higher body mass index, total and low-density lipoprotein cholesterol and triglyceride levels, and lower high-density lipoprotein cholesterol levels. During the first year 5.2% of patients died. A comparison of one-year mortality according to admission plasma glucose quartiles demonstrated a significant and progressive increase in mortality risk as admission plasma glucose rose (3.5%, 4.1%, 6.1%, 6.4%, respectively, p=0.001). However, this association lost its clinical significance following a multivariate analysis ( p=0.08).

CONCLUSIONS

High admission plasma glucose levels within the normal to mildly impaired range are associated with increased one-year mortality in non-diabetic acute coronary syndrome patients. However, the higher glucose level is probably not the cause for the adverse outcome but rather a marker for high risk. Our findings support the definition of 140 mg/dl as the cutoff for clinically acceptable admission glucose levels in patients with acute coronary syndrome.

Splenic leukocytes mediate the hyperglycemic exacerbation of myocardial infarct size in mice

Acute hyperglycemia during acute myocardial infarction is associated with worse myocardial injury and increased mortality. Using a mouse model of myocardial ischemia/reperfusion injury, we tested the hypothesis that acute hyperglycemia activates splenic leukocytes and subsequently exacerbates myocardial infarct size. We then examined whether the adverse effects of hyperglycemia could be attenuated by a potent anti-inflammatory agent (an agonist of the adenosine A2A receptor) administered immediately prior to reperfusion. C57BL6 (WT) mice underwent 30-min LAD occlusion and 60-min reperfusion with or without prior splenectomy. Acute hyperglycemia before ischemia increased myocardial infarct size (IS) by 43% (p < 0.05). Splenectomy before ischemia did not change IS (vs. control, p = NS) but did serve to prevent the exacerbation of IS by hyperglycemia. Acute hyperglycemia activated splenic leukocytes by increasing formyl peptide receptor expression and reactive oxygen species production before ischemia, and enhanced splenic neutrophil release with resultant peripheral neutrophilia and increased myocardial neutrophil infiltration during reperfusion. Acute adoptive transfer of splenic leukocytes to splenectomized mice before ischemia restored the hyperglycemic exacerbation of infarct size. ATL146e, an adenosine 2A receptor (A2AR) agonist, abolished neutrophilia during reperfusion and reduced IS in hyperglycemic mice. ATL146e also reduced IS in splenectomized hyperglycemic mice with transfer of WT splenic leukocytes, but not with transfer of splenic leukocytes from A2AR knockout mice. Acute hyperglycemia prior to myocardial ischemia and reperfusion exacerbates IS by activating splenic leukocytes. ATL146e administered at reperfusion suffices to abrogate the hyperglycemic exacerbation of IS by acting on A2ARs on splenic leukocytes.