Fluorescent advanced glycation end products and their soluble receptor: the birth of new plasmatic biomarkers for risk stratification of acute coronary syndrome.

OBJECTIVE: Advanced glycation end products (AGEs) have pathophysiological implications in cardiovascular diseases. The aim of our study was to evaluate the prognostic value of fluorescent AGEs and its soluble receptor (sRAGE) in the context of acute coronary syndrome (ACS), both in-hospital phase and follow-up period. METHODS: A prospective clinical study was performed in patients with debut's ACS. The endpoints were the development of cardiac events (cardiac deaths, re-infarction and new-onset heart failure) during in-hospital phase and follow-up period (366 days, inter-quartile range: 273-519 days). 215 consecutive ACS patients admitted to the coronary care unit (62.7±13.0 years, 24.2% female) were included. 47.4% had a diagnosis of ST segment elevation myocardial infarction. AGEs and sRAGE were analysed by fluorescence spectroscopy and competitive ELISA, respectively. Risk scores (GRACE, TIMI, PURSUIT) were calculated retrospectively using prospective data. The complexity of coronary artery disease was evaluated by SYNTAX score. RESULTS: The mean fluorescent AGEs and sRAGE levels were 57.7±45.1 AU and 1045.4±850.0 pg/mL, respectively. 19 patients presented cardiac events during in-hospital phase and 29 during the follow-up. In-hospital cardiac events were significantly associated with higher sRAGE levels (p = 0.001), but not long-term cardiac events (p = 0.365). Regarding fluorescent AGE the opposite happened. After multivariate analysis correcting by gender, left ventricular ejection fraction, glucose levels, haemoglobin, GRACE and SYNTAX scores, sRAGE was significantly associated with in-hospital prognosis, whereas fluorescent AGEs was significantly associated with long-term prognosis. CONCLUSIONS: We conclude that elevated values of sRAGE are associated with worse in-hospital prognosis, whereas high fluorescent AGE levels are associated with more follow-up events.

Statins modulate feedback regulation mechanisms between advanced glycation end-products and C-reactive protein: evidence in patients with acute myocardial infarction.

OBJECTIVE: High sensitivity C-reactive protein (hsCRP) and advanced glycation end-products (AGEs) have been proposed as mediators in inflammation and atherosclerosis. Therefore, we studied the relation between AGE and hsCRP in patients with acute myocardial infarction (AMI). METHODS: Patients with AMI diagnosis and satisfying our inclusion criteria were included during 2009-2011 in an unicentre registry of AMI patients for a cross-sectional study. The final cohort was composed of 156 patients (46.2% STEMI and 27.6% with type-2 diabetes). AGE and hsCRP were measured in plasma. RESULTS: Diabetic patients were older than non-diabetics (68.6 ± 10.6 vs. 60.4 ± 13.9 years; p<0.05), presented more incidence of hypertension (62.8 vs. 36.3%; p<0.05) and were in a higher Killip class (p<0.05). The mean values of fluorescent AGE and hsCRP levels were 61.3 ± 49.8 AU and 2.4 ± 4.0 mg/L, respectively, and there were no differences in these parameters between diabetic and non-diabetic patients. A direct association between AGE and hsCRP levels was observed, mainly in diabetic patients (r=0.258; p=0.018). Importantly, this association disappeared in patients who had been treated with statins before their AMI (r=-0.055; p=0.845), but it was maintained in non-diabetic patients naïve for statins treatment (r=0.634; p<0.001), independently of other treatments and confounding parameters. CONCLUSIONS: This is the first evidence in humans of a feedback regulation mechanism between CRP and the AGE-RAGE axis modulated by statins.

High-sensitivity C-reactive protein predicts adverse outcomes after non-ST-segment elevation acute coronary syndrome regardless of GRACE risk score, but not after ST-segment elevation myocardial infarction.

INTRODUCTION: Atherosclerosis is an active process and the inflammatory component appears to be particularly correlated with the development of acute coronary syndromes (ACS). C-reactive protein (CRP) is an acute phase protein that appears in the circulation in response to inflammatory cytokines. The present study investigated the association between high-sensitivity C-reactive protein (hsCRP) on admission and follow-up prognosis after an ACS. METHODS: We included 151 consecutive patients admitted to the coronary care unit with a diagnosis of ACS (47% ST-segment elevation myocardial infarction [STEMI]). The primary endpoint was the combination of cardiac death and myocardial reinfarction during the follow-up period (median 19.8 months, interquartile range 16.3-23.7 months). RESULTS: The occurrence of follow-up events was significantly related to admission hsCRP level, which was an excellent predictor of cardiac death and reinfarction during follow-up (HR 1.091, 95% CI 1.014-1.174; p=0.019). Stratifying the population based on type of ACS, adjusted by variables associated with cardiac events in univariate analysis (hsCRP, diabetes, depressed ejection fraction and GRACE risk score), hsCRP proved to be an independent predictor of follow-up outcomes only in non-STEMI patients (HR 1.217, 95% CI: 1.093-1.356, p<0.001), not in STEMI patients. The best cutoff level of hsCRP to predict follow-up outcomes was 1.1mg/dl, with sensitivity of 77.8% and specificity of 63.2%. CONCLUSION: Although the GRACE risk score is routinely used for stratification of patients with ACS, assessment of hsCRP may provide additional prognostic value in the follow-up of non-STEMI patients.

Predictive value of advanced glycation end products for the development of post-infarction heart failure: a preliminary report.

BACKGROUND: Since post-infarction heart failure (HF) determines a great morbidity and mortality, and given the physiopathology implications of advanced glycation end products (AGE) in the genesis of myocardial dysfunction, it was intended to analyze the prognostic value of these molecules in order to predict post-infarction HF development. METHODS: A prospective clinical study in patients after first acute coronary syndrome was conducted. The follow-up period was consisted in 1 year. In 194 patients consecutively admitted in the coronary unit for myocardial infarct fluorescent AGE levels were measured. The association between glycaemic parameters and the development of post-infarction HF were analyzed in those patients. Finally, we identified the variables with independent predictor value by performing a multivariate analysis of hazard ratio for Cox regression. RESULTS: Eleven out of 194 patients (5.6%) developed HF during follow-up (median: 1.0 years [0.8 - 1.5 years]). Even though basal glucose, fructosamine and glycated haemoglobin were significant predictive factors in the univariate analysis, after being adjusted by confounding variables and AGE they lost their statistical signification. Only AGE (Hazard Ratio 1.016, IC 95%: 1.006-1.026; p<0,001), together with NT-proBNP and the infarct extension were predictors for post-infarction HF development, where AGE levels over the median value 5-fold increased the risk of HF development during follow-up. CONCLUSIONS: AGE are an independent marker of post-infarction HF development risk.