0000000000073926

AUTHOR

Till Keller

0000-0002-0895-6491

Making it More Sensitive

About a decade ago, the prevailing wisdom was that conventional risk factors explained only approximately half of the risk for a myocardial infarction or stroke. Consequently, efforts to identify novel risk factors were undertaken to improve cardiovascular risk prediction. The hypothesis that inflammation is a central contributor to atherothrombosis has stimulated sustained efforts to characterize the specific molecules and pathways that may be involved and to identify biomarkers in humans that enable detection of underlying inflammatory activation to improve cardiovascular risk prediction. Ridker et al1 pioneered this work and reported that systemic low-grade inflammation assessed by measu…

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Diagnostic and prognostic performance of myeloperoxidase plasma levels compared with sensitive troponins in patients admitted with acute onset chest pain.

Background— Activation of leukocytes with release of myeloperoxidase (MPO) has been linked to acute coronary disease. To date, studies investigating the diagnostic and prognostic performance of circulating MPO in patients with chest pain (CP) are mainly retrospective, of low size, and lack a cut-off value for MPO. Herein, we prospectively assess the diagnostic and prognostic properties of MPO compared with sensitive troponin I (sTNI) in patients admitted to the emergency room with CP. Methods and Results— One thousand, eight hundred and eighteen consecutive patients (mean age, 61.4±13.5 years; 33.6% female) admitted for CP underwent determination of MPO, sTnI, and B-natriuretic peptide pla…

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Relations of Sex to Diagnosis and Outcomes in Acute Coronary Syndrome

Background The atypical presentation of women with acute coronary syndrome ( ACS ) has been related to delayed diagnosis and treatment, which may explain worse outcome compared with men. Methods and Results We analyzed pooled data of 2520 patients of 2 prospective cohorts in terms of differences in presentation and management of women and men suggestive of ACS . Using logistic regression, we established 2 diagnostic models and tested their diagnostic performance in both sexes separately. Sex‐specific differences in management of patients with ACS were ascertained and a 2‐year follow‐up was performed. Women were older than men (median 67 versus 61 years, P =0.001), had more often dyspnea (2…

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Assessment of microRNAs in patients with unstable angina pectoris.

Aims While cardiac troponin measurements have significantly improved the early diagnosis of myocardial infarction, the timely biomarker-based diagnosis of unstable angina pectoris (UAP) remains a major unmet clinical challenge. The aim of this study was to assess levels of circulating microRNAs (miRNAs) as possible novel biomarkers in patients with UAP. Methods and results A three-phase approach was conducted, comprising (i) profiling of miRNAs in patients with UAP and controls groups; (ii) replication of significant miRNAs in an independent patient cohort, (iii) validation of a multi-miRNAs panel in a third cohort. Out of 25 miRNAs selected for replication, 8 miRNAs remained significantly …

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Association of MR-proadrenomedullin with cardiovascular risk factors and subclinical cardiovascular disease.

Abstract Aims and background Midregional proadrenomedullin (MR-proADM) is a protein, which exerts various effects on the cardiovascular system. Recent studies underscored its prognostic implications in patients with acute dyspnea and cardiovascular diseases. Therefore, we aimed to determine the distribution of MR-proADM in the general population and to reveal potential associations of MR-proADM with cardiovascular risk factors and measures of subclinical cardiovascular disease. Methods and results MR-proADM plasma concentrations were determined in individuals of the population-based cohort of the Gutenberg Health Study ( N  = 5000) using a commercially available fluoroimmunoassay. Individua…

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P6456Neopterin for risk stratification of patients with acute chest pain

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GDF-15 predicts cardiovascular events in acute chest pain patients

Background Treatment of patients presenting with possible acute myocardial infarction (AMI) is based on timely diagnosis and proper risk stratification aided by biomarkers. We aimed at evaluating the predictive value of GDF-15 in patients presenting with symptoms suggestive of AMI. Methods Consecutive patients presenting with suspected AMI were enrolled in three study centers. Cardiovascular events were assessed during a follow-up period of 6 months with a combined endpoint of death or MI. Results From the 1818 enrolled patients (m/f = 1208/610), 413 (22.7%) had an acute MI and 63 patients reached the combined endpoint. Patients with MI and patients with adverse outcome had higher GDF-15 le…

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Low Homoarginine Levels in the Prognosis of Patients With Acute Chest Pain.

Background The endogenous amino acid homoarginine predicts mortality in cerebro‐ and cardiovascular disease. The objective was to explore whether homoarginine is associated with atrial fibrillation ( AF ) and outcome in patients with acute chest pain. Methods and Results One thousand six hundred forty‐nine patients with acute chest pain were consecutively enrolled in this study, of whom 589 were diagnosed acute coronary syndrome ( ACS ). On admission, plasma concentrations of homoarginine as well as brain natriuretic peptide ( BNP ), and high‐sensitivity assayed troponin I (hsTnI) were determined along with electrocardiography ( ECG ) variables. During a median follow‐up of 183 days, 60 ma…

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Troponin I Assay for Identification of a Significant Coronary Stenosis in Patients with Suspected Acute Myocardial Infarction and Wide QRS Complex

Background Common ECG criteria such as ST-segment changes are of limited value in patients with suspected acute myocardial infarction (AMI) and bundle branch block or wide QRS complex. A large proportion of these patients do not suffer from an AMI, whereas those with ST-elevation myocardial infarction (STEMI) equivalent AMI benefit from an aggressive treatment. Aim of the present study was to evaluate the diagnostic information of cardiac troponin I (cTnI) in hemodynamically stable patients with wide QRS complex and suspected AMI. Methods In 417 out of 1818 patients presenting consecutively between 01/2007 and 12/2008 in a prospective multicenter observational study with suspected AMI a pro…

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Cystatin C and cardiovascular mortality in patients with coronary artery disease and normal or mildly reduced kidney function: results from the AtheroGene study

Aims Chronic kidney disease is associated with increased risk of cardiovascular disease. Cystatin C is a promising marker to reliably mirror renal function. The role of cystatin C in patients with coronary artery disease (CAD) and normal or mildly reduced kidney function is the subject of current investigation. Methods and results In 2162 patients, over the whole spectrum of CAD, baseline cystatin C concentrations were measured. Patients with an estimated glomerular filtration rate of ≤60 mL/min per 1.73 m2 ( n = 295) were excluded. In patients with complete follow-up information ( n = 1827), 66 cardiovascular deaths were registered during a median follow-up of 3.65 years. Logarithmically t…

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Estimation of Values below the Limit of Detection of a Contemporary Sensitive Troponin I Assay Improves Diagnosis of Acute Myocardial Infarction

Abstract BACKGROUND The limit of detection (LoD) is the minimal amount of a substance that can be consistently detected. In the diagnosis of acute myocardial infarction (AMI) many patients present with troponin concentrations below the LoD of contemporary sensitive cardiac troponin I (cs-cTnI) assays. These censored values below the LoD influence the diagnostic performance of these assays compared to highly sensitive cTnI (hs-cTnI) assays. Therefore we assessed the impact of a new approach for interpolation of the left-censored data of a cs-cTnI assay in the evaluation of patients with suspected AMI. METHODS Our posthoc analysis used a real world cohort of 1818 patients with suspected MI. D…

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Prognostic information of glycogen phosphorylase isoenzyme BB in patients with suspected acute coronary syndrome.

Early and adequate risk stratification is essential in patients with suspected acute coronary syndrome (ACS). The aim of the present study was to investigate whether glycogen phosphorylase BB (GPBB) could add prognostic information in the context of contemporary sensitive troponin I determination and B-type natriuretic peptide (BNP). Patients with suspected ACS were consecutively enrolled at 3 German study centers from January 2007 through December 2008. Troponin I, GPBB, and BNP were determined at admission. Follow-up information on the combined end point of death, myocardial infarction, revascularization, and hospitalization owing to a cardiovascular cause was obtained 6 months after enro…

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Cardiac Troponins for the Diagnosis of Acute Myocardial Infarction in Chronic Kidney Disease

Background Patients with chronic kidney disease ( CKD ) are at high risk of myocardial infarction. Cardiac troponins are the biomarkers of choice for the diagnosis of acute myocardial infarction ( AMI ) without ST ‐segment elevation ( NSTE ). In patients with CKD , troponin levels are often chronically elevated, which reduces their diagnostic utility when NSTE ‐ AMI is suspected. The aim of this study was to derive a diagnostic algorithm for serial troponin measurements in patients with CKD and suspected NSTE ‐ AMI . Methods and Results Two cohorts, 1494 patients from a prospective cohort study with high‐sensitivity troponin I (hs‐ cTnI ) measurements and 7059 cases from a clinical registr…

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Release kinetics of early ischaemic biomarkers in a clinical model of acute myocardial infarction

ObjectiveTo determine the release kinetics of different biomarkers with potential as novel early ischaemic biomarkers in patients with acute coronary syndrome (ACS); it is difficult to establish the detailed release kinetics in patients with acute myocardial infarction (AMI).MethodsWe analysed the release kinetics of soluble fms-like tyrosine kinase (sFlt-1), ischaemia modified albumin (IMA), and heart-type fatty acid binding protein (hFABP) in patients with hypertrophic obstructive cardiomyopathy who were undergoing transcoronary ablation of septal hypertrophy (TASH), a procedure mimicking AMI. Consecutive patients (n=21) undergoing TASH were included. Blood samples were collected before T…

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Copeptin Improves Early Diagnosis of Acute Myocardial Infarction

ObjectivesEarly identification of myocardial infarction in chest pain patients is crucial to identify patients at risk and to maintain a fast treatment initiation.BackgroundThe aim of the current investigation is to test whether determination of copeptin, an indirect marker for arginin-vasopressin, adds diagnostic information to cardiac troponin in early evaluation of patients with suspected myocardial infarction.MethodsBetween January 2007 and July 2008, patients with suspected acute coronary syndrome were consecutively enrolled in this multicenter study. Copeptin, troponin T (TnT), myoglobin, and creatine kinase-myocardial band were determined at admission and after 3 and 6 h.ResultsOf 1,…

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Sensitive Troponin I Assay in Early Diagnosis of Acute Myocardial Infarction

BACKGROUND Cardiac troponin testing is central to the diagnosis of acute myocardial infarction. We evaluated a sensitive troponin I assay for the early diagnosis and risk stratification of myocardial infarction. METHODS In a multicenter study, we determined levels of troponin I as assessed by a sensitive assay, troponin T, and traditional myocardial necrosis markers in 1818 consecutive patients with suspected acute myocardial infarction, on admission and 3 hours and 6 hours after admission. RESULTS For samples obtained on admission, the diagnostic accuracy was highest with the sensitive troponin I assay (area under the receiver-operating-characteristic curve [AUC], 0.96), as compared with t…

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Midregional Proadrenomedullin for Prediction of Cardiovascular Events in Coronary Artery Disease: Results from the AtheroGene Study

Abstract BACKGROUND Midregional proadrenomedullin (MR-proADM) is a newly identified prognostic marker in heart failure. We evaluated the prognostic impact of MR-proADM in a cohort of patients with symptomatic coronary artery disease according to their clinical presentation. METHODS We measured baseline MR-proADM concentrations in 2240 individuals from the prospective AtheroGene study and evaluated the prognostic impact on future fatal and nonfatal cardiovascular events during a follow-up period of 3.6 (1.6) years. RESULTS The sample comprised 1355 individuals with stable angina pectoris (SAP) and 885 with acute coronary syndrome (ACS). A cardiovascular event occurred in 192 people. Individu…

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Distribution and categorization of left ventricular measurements in the general population: results from the population-based Gutenberg Heart Study.

Background— Echocardiography, the dominant imaging modality for quantification of left ventricular metrics, has undergone continuing development in the past few decades. However, given the lack of population-based data, current guidelines are still based on restricted and small data sets analyzed with methods including expert opinion. This work presents empirically derived reference values from a large-scale, epidemiologic study conducted with state-of-the-art imaging technology and methods. Methods and Results— The distribution of echocardiographic measurements of the left ventricle was analyzed in a population-based sample of 5000 mid-Europeans from the Gutenberg Heart Study in Germany. …

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High-sensitivity troponin and novel biomarkers for the early diagnosis of non-ST-segment elevation myocardial infarction in patients with atrial fibrillation.

To evaluate the diagnostic performance of high-sensitivity troponin I (hsTnI) and other novel biomarkers for diagnosing non-ST-segment elevation myocardial infarction (NSTEMI) in patients with atrial fibrillation.In an acute chest pain cohort (N=1673), mean age 61.4±13.6 (34% female), we measured hsTnI and 13 established and novel biomarkers reflecting ischaemia, necrosis, inflammation, myocardial stress, angiogenesis on admission and after three hours in order to investigate their diagnostic accuracy for NSTEMI.In atrial fibrillation patients (N=299) hsTnI on admission had the best discriminatory ability for NSTEMI (area under the curve 0.97) with only two novel biomarkers, copeptin and he…

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Non-Invasive Approach for Evaluation of Pulmonary Hypertension Using Extracellular Vesicle-Associated Small Non-Coding RNA.

Extracellular vesicles are released by numerous cell types of the human body under physiological but also under pathophysiological conditions. They are important for cell&ndash

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Gender-specific diagnosis of acute myocardial infarction using high-sensitivity assayed cardiac troponin I

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Mid-regional pro-atrial natriuretic peptide and copeptin as indicators of disease severity and therapy response in CTEPH

Background Chronic thromboembolic pulmonary hypertension (CTEPH) leads to right heart failure. Pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) restore pulmonary haemodynamics and allow cardiac recovery. This study examined the relationship of copeptin and mid-regional pro-atrial natriuretic peptide (MR-proANP) levels to disease severity and therapy response. Methods This observational cohort study included 125 patients (55 PEA/70 BPA) who underwent treatment and completed a 6-/12-month follow-up. Biomarkers, measured at baseline, prior to every BPA and at follow-up, were compared to 1) severe disease at baseline (right atrial pressure (RAP) ≥8 mmHg and cardiac index ≤2…

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Association of adiponectin with adverse outcome in coronary artery disease patients: results from the AtheroGene study

In primary prevention, the adipocytokine adiponectin seems to be protective against diabetes mellitus and cardiovascular disease. Data in patients with manifest coronary artery disease (CAD) are scant stimulating the investigation of the association of adiponectin concentrations and cardiovascular outcome in a prospective CAD cohort.In 1890 consecutive patients with documented CAD [1130 with stable angina (SAP) and 760 with acute coronary syndrome (ACS)] baseline concentrations of adiponectin were measured by enzyme-linked immuno assay. During a median follow-up of 2.5 years cardiovascular events were registered (cardiovascular deaths 70; non-fatal myocardial infarction 46). Baseline adipon…

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Identification of acute myocardial infarction in elderly patients using optimized highly sensitive troponin I thresholds

Purpose: Established diagnostic thresholds for high-sensitivity cardiac troponins (hs-cTn) might not apply for elderly patients as they are elevated irrespective of the presence of an acute myocardial infarction (AMI). Aim of the present study was to investigate hs-cTnI in elderly patients with suspected AMI and to calculate optimized diagnostic cutoffs. Material and methods: Data from a prospective multi-centre study and from a second independent prospective single-centre cohort study were analysed. A number of 2903 patients were eligible for further analysis. Patients > 70 years were classified as elderly. hs-cTnI was measured upon admission. Results: Around 34.7% of 2903 patients were…

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Gender-specific diagnostic performance of a new high-sensitivity cardiac troponin I assay for detection of acute myocardial infarction.

The determination of cardiac troponin is essential for diagnosing myocardial infarction. A troponin I assay has recently been developed that provides the highest analytical sensitivity to date.The analysis included 1560 patients with chest pain, of whom 1098 were diagnosed with non-coronary chest pain, 189 with unstable angina pectoris and 273 with non-ST-segment elevation myocardial infarction. The troponin I concentration was determined on admission (0 hours) and 3 hours later. The diagnostic algorithm incorporated troponin I elevation above the gender-specific 99th percentile as well as predefined relative or absolute 3-hour changes in the troponin I concentration (delta).The diagnostic …

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Defining a reference population to determine the 99th percentile of a contemporary sensitive cardiac troponin I assay

Abstract Background Diagnosis of acute myocardial infarction (AMI) according to the universal definition is based on ischemic symptoms, imaging findings and elevated myocardial necrosis markers, preferably cardiac troponin I/T with diagnostic threshold representing the 99th percentile of a reference population. It is not clearly defined if this should be an unselected population-based or a healthy cohort with respect to cardiac diseases. Aim of the current study was to describe the distribution of troponin I using a sensitive assay and to evaluate the impact of cardiac diseases and cardiovascular risk factors in apparently healthy individuals. Methods Troponin I was determined using a conte…

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Urinary neutrophil gelatinase-associated lipocalin and cystatin C compared to the estimated glomerular filtration rate to predict risk in patients with suspected acute myocardial infarction.

Abstract Introduction Impaired renal function, reflected by estimated glomerular filtration rate (eGFR) or cystatin C, is a strong risk predictor in the presence of acute myocardial infarction (AMI). Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is an early marker of acute kidney injury. uNGAL might also be a good predictor of outcome in patients with cardiovascular disease. Aim of the present study was to evaluate the prognostic value of uNGAL compared to eGFR and cystatin C in patients with suspected AMI. Methods 1818 patients were enrolled with suspected AMI. Follow-up information on the combined endpoint of death or non-fatal myocardial infarction was obtained 6months after…

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