Circulating microparticles, protein C, free protein S and endothelial vascular markers in children with sickle cell anaemia.

INTRODUCTION: Circulating microparticles (MP) have been described in sickle cell anaemia (SCA); however, their interaction with endothelial markers remains unclear. We investigated the relationship between MP, protein C (PC), free protein S (PS), nitric oxide (NO), endothelin-1 (ET-1) and adrenomedullin (ADM) in a large cohort of paediatric patients. METHOD: A total of 111 children of African ethnicity with SCA: 51 in steady state; 15 in crises; 30 on hydroxyurea (HU) therapy; 15 on transfusion; 17 controls (HbAA) of similar age/ethnicity. MP were analysed by flow cytometry using: Annexin V (AV), CD61, CD42a, CD62P, CD235a, CD14, CD142 (tissue factor), CD201 (endothelial PC receptor), CD62E, CD36 (TSP-1), CD47 (TSP-1 receptor), CD31 (PECAM), CD144 (VE-cadherin). Protein C, free PS, NO, pro-ADM and C-terminal ET-1 were also measured. RESULTS: Total MP AV was lower in crisis (1.26×10(6) ml(-1); 0.56-2.44×10(6)) and steady state (1.35×10(6) ml(-1); 0.71-3.0×10(6)) compared to transfusion (4.33×10(6) ml(-1); 1.6-9.2×10(6), p<0.01). Protein C levels were significantly lower in crisis (median 0.52 IU ml(-1); interquartile range 0.43-0.62) compared with all other groups: HbAA (0.72 IU ml(-1); 0.66-0.82, p<0.001); HU (0.67 IU ml(-1); 0.58-0.77, p<0.001); steady state (0.63 IU ml(-1); 0.54-0.70, p<0.05) and transfusion (0.60 IU ml(-1); 0.54-0.70, p<0.05). In addition, levels were significantly reduced in steady state (0.63 IU ml(-1); 0.54-0.70) compared with HbAA (0.72 IU ml(-1); 0.66-0.80, p<0.01). PS levels were significantly higher in HbAA (0.85 IU ml(-1); 0.72-0.97) compared with crisis (0.49 IU ml(-1); 0.42-0.64, p<0.001), HU (0.65 IU ml(-1); 0.56-0.74, p<0.01) and transfusion (0.59 IU ml(-1); 0.47-0.71, p<0.01). There was also a significant difference in crisis patients compared with steady state (0.49 IU ml(-1); 0.42-0.64 vs. 0.68 IU ml(-1); 0.58-0.79, p<0.05). There was high correlation (R>0.9, p<0.05) between total numbers of AV-positive MP (MP AV) and platelet MP expressing non-activation platelet markers. There was a lower correlation between MP AV and MP CD62P (R=0.73, p<0.05) (platelet activation marker), and also a lower correlation between percentage of MP expressing CD201 (%MP CD201) and %MP CD14 (R=0.627, p<0.001). %MP CD201 was higher in crisis (11.6%) compared with HbAA (3.2%, p<0.05); %MP CD144 was higher in crisis (7.6%) compared with transfusion (2.1%, p<0.05); %CD14 (0.77%) was higher in crisis compared with transfusion (0.0%, p<0.05) and steady state (0.0%, p<0.01); MP CD14 was detectable in a higher number of samples (92%) in crisis compared with the rest (40%); %MP CD235a was higher in crisis (17.9%) compared with transfusion (8.9%), HU (8.7%) and steady state (9.9%, p<0.05); %CD62E did not differ significantly across the groups and CD142 was undetectable. Pro-ADM levels were raised in chest crisis: 0.38 nmol L(-1) (0.31-0.49) versus steady state: 0.27 nmol L(-1) (0.25-0.32; p<0.01) and control: 0.28 nmol L(-1) (0.27-0.31; p<0.01). CT-proET-1 levels were reduced in patients on HU therapy: 43.6 pmol L(-1) (12.6-49.6) versus control: 55.1 pmol L(-1) (45.2-63.9; p<0.05). NO levels were significantly lower in chest crisis (19.3 mmol L(-1) plasma; 10.7-19.9) compared with HU (22.2 mmol L(-1) plasma; 18.3-28.4; p<0.05), and HbSC (30.6 mmol L(-1) plasma; 20.8-39.5; p<0.05) and approach significance when compared with steady state (22.5mmol L(-1) plasma; 16.9-28.2; p=0.07). CONCLUSION: Protein C and free PS are reduced in crisis with lower numbers of platelet MP and higher percentage of markers of endothelial damage and of red cell origin. During chest crisis, ADM and ET-1 were elevated suggesting a role for therapy inhibiting ET-1 in chest crisis.

Multiple biomarkers and atrial fibrillation in the general population.

BACKGROUND: Different biological pathways have been related to atrial fibrillation (AF). Novel biomarkers capturing inflammation, oxidative stress, and neurohumoral activation have not been investigated comprehensively in AF. METHODS AND RESULTS: In the population-based Gutenberg Health Study (n = 5000), mean age 56 ± 11 years, 51% males, we measured ten biomarkers representing inflammation (C-reactive protein, fibrinogen), cardiac and vascular function (midregional pro adrenomedullin [MR-proADM], midregional pro atrial natriuretic peptide [MR-proANP], N-terminal pro-B-type natriuretic peptide [Nt-proBNP], sensitive troponin I ultra [TnI ultra], copeptin, and C-terminal pro endothelin-1), and oxidative stress (glutathioneperoxidase-1, myeloperoxidase) in relation to manifest AF (n = 161 cases). Individuals with AF were older, mean age 64.9 ± 8.3, and more often males, 71.4%. In Bonferroni-adjusted multivariable regression analyses strongest associations per standard deviation increase in biomarker concentrations were observed for the natriuretic peptides Nt-proBNP (odds ratio [OR] 2.89, 99.5% confidence interval [CI] 2.14-3.90; P<0.0001), MR-proANP (OR 2.45, 99.5% CI 1.91-3.14; P<0.0001), the vascular function marker MR-proADM (OR 1.54, 99.5% CI 1.20-1.99; P<0.0001), TnI ultra (OR 1.50, 99.5% CI 1.19-1.90; P<0.0001) and. fibrinogen (OR 1.44, 99.5% CI 1.19-1.75; P<0.0001). Based on a model comprising known clinical risk factors for AF, all biomarkers combined resulted in a net reclassification improvement of 0.665 (99.3% CI 0.441-0.888) and an integrated discrimination improvement of >13%. CONCLUSIONS: In conclusion, in our large, population-based study, we identified novel biomarkers reflecting vascular function, MR-proADM, inflammation, and myocardial damage, TnI ultra, as related to AF; the strong association of natriuretic peptides was confirmed. Prospective studies need to examine whether risk prediction of AF can be enhanced beyond clinical risk factors using these biomarkers.

Associations of methylarginines and homoarginine with diastolic dysfunction and cardiovascular risk factors in patients with preserved left ventricular ejection fraction.

BACKGROUND: Asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and homoarginine are considered to modulate nitric oxide synthesis. We evaluated whether ADMA, SDMA, and homoarginine are associated with diastolic dysfunction. METHODS AND RESULTS: We investigated primary care patients at cardiovascular risk with preserved left ventricular ejection fraction from the multicenter DIAST-CHF study. We measured serum concentrations of ADMA, SDMA, and homoarginine and performed standardized echocardiographic examinations. Among 1,396 patients (mean age 65.3 ± 8.3 y, 54.6% women), diastolic dysfunction was ruled out in 261 patients (18.7%). Mild and moderate/severe grades of diastolic dysfunction were present in 900 (64.5%) and 235 (16.8%) study participants, respectively. After adjustments for cardiovascular risk factors, ADMA and SDMA were positively and homoarginine negatively associated with N-terminal pro-B-type natriuretic peptide and midregional pro-adrenomedullin (P < .05 for all). Lower homoarginine levels were associated with diastolic dysfunction, and higher ADMA and SDMA levels were associated with the severity of diastolic dysfunction (P < .05 for all). CONCLUSIONS: Higher levels of ADMA and SDMA and lower levels of homoarginine are associated with an adverse cardiovascular risk profile and diastolic dysfunction. Further studies should clarify the potential of these amino acid derivatives for the therapy of cardiovascular diseases.

Midregional pro-atrial natriuretic peptide in the general population/Insights from the Gutenberg Health Study.

BACKGROUND: The use of biomarkers is firmly established for the assessment of cardiovascular disease. Emerging biomarkers such as midregional pro-atrial natriuretic peptide (MR-proANP) challenge established markers regarding risk prediction and stratification ability. The aim of the present study was to describe the distribution of a contemporary MR-proANP assay in a large population-representative sample and to evaluate the association with prevalent cardiac diseases and cardiovascular risk factors. METHODS: MR-proANP was determined by the use of a contemporary commercially available assay (BRAHMS GmbH, Hennigsdorf, Germany) in a representative sample of 5000 participants from the large population-based Gutenberg Health Study. N-terminal pro B-type natriuretic peptide (NT-proBNP) was used as a comparator. RESULTS: Mean age was 55.5 ± 10.9 years. Coronary artery disease (CAD) was documented in 4.6%, heart failure (HF) in 1.5% of the study participants. We observed a moderate to strong correlation of the biomarkers with age, diabetes, hypertension, smoking, renal function, prevalence of CAD and HF. Males showed lower MR-proANP concentrations than females. MR-proANP showed no relevant correlation with BMI (ρ=-0.030) and CRP (ρ=0.039). Reference limits for MR-proANP representing the 95th/97.5th/99th percentile were determined for healthy individuals with 116/132/169 pmol/mL. CONCLUSIONS: The current analysis in a large population-based sample elucidates the correlations and distribution of MR-proANP. Its concentration in healthy individuals depends on prevalent cardiovascular diseases and classical risk factors. The reported population-based reference values might be useful for distinguishing between healthy and diseased individuals, thus improving risk stratification and triaging in various clinical settings.

MR-proANP and MR-proADM for risk stratification of patients with acute chest pain.

OBJECTIVE: To evaluate mid-regional pro-adrenomedullin (MR-proADM) and mid-regional pro-atrial natriuretic peptide (MR-proANP) as prognostic biomarkers in a representative 'real world' cohort of patients with suspected acute coronary syndrome (ACS). DESIGN: Prospective observational multicentre cohort study. SETTING: Chest pain units of three major hospitals in Germany from 2007 to 2008. PATIENTS: Patients presenting with signs and symptoms suggestive of an ACS. MAIN OUTCOME MEASURES: Primary end point was death or non-fatal myocardial infarction (MI), and secondary end point was death, non-fatal MI, stroke, need for coronary revascularisation, and hospital admission for cardiovascular cause or acute heart failure within 6 months after enrolment. RESULTS: 1386 patients (male/female = 920/466) were enrolled. Follow-up information was available for 97.8% of patients (median follow-up time 183 days). Forty-three patients reached the primary end point, and 132 the secondary end point. Patients who reached a primary end point had significantly higher MR-proANP (271 vs 101 pmol/l, p < 0.001) and MR-proADM (0.86 vs 0.59 nmol/l, p < 0.001) concentrations than those who did not. Cox regression analysis revealed a 2.55-fold risk of death or non fatal MI (95% CI 1.48 to 2.46, p < 0.001) for an increment of the log-transformed MR-proANP concentration by 1 SD after adjustment for cardiovascular risk factors, and a 1.91-fold risk (95% CI 1.48 to 2.46, p < 0.001) for MR-proADM. Both peptides could result in significant reclassification of patients when added to the Global Registry of Acute Coronary Events risk score, with an overall net reclassification improvement of 41.2% for MR-proADM and 35.7% for MR-proANP. CONCLUSIONS: MR-proADM and MR-proANP are predictors of future cardiovascular events in patients presenting with acute chest pain and might facilitate the choice of treatment in those patients complementary to established risk scores.

Multiple endothelial biomarkers and noninvasive vascular function in the general population: the Gutenberg Health Study.

Vascular reactivity is reflected by blood biomarkers and noninvasive vascular function measurement. The relation of biomarkers to flow-mediated dilation and peripheral arterial tonometry in the general population is little understood. In 5000 individuals (mean age, 56±11 years; age range, 35-74 years; 49% women) of the population-based Gutenberg Health Study we simultaneously assessed 6 biomarkers of cardiovascular function (midregional proadrenomedullin [MR-proADM], midregional pro atrial natriuretic peptide [MR-proANP], N-terminal pro B-type natriuretic peptide, copeptin, C-terminal proendothelin 1, and neopterin) in relation to flow-mediated dilation and peripheral arterial tonometry. Strongest partial correlations (adjusted for age and sex) were observed for baseline pulse amplitude with MR-proADM (r=0.13) and MR-proANP (r=-0.13); hyperemic response variables showed the highest correlation for MR-proADM and peripheral arterial tonometry ratio (r=-0.14). In multivariable linear regression models, strongest associations with baseline vascular function were observed for MR-proANP with baseline pulse amplitude (ß per SD increase [99.17%], -0.080 [-0.115 to -0.044]; P<0.0001 after Bonferroni correction for multiple testing) and MR-proADM (-0.044 [-0.070 to -0.017]; P<0.0001), as well as MR-proANP (-0.033 [-0.057 to -0.009]; P=0.0017) and N-terminal pro B-type natriuretic peptide (-0.027 [-0.051 to -0.003]; P=0.015) with brachial artery diameter. For hyperemic response variables, highest associations were seen for peripheral arterial tonometry ratio with MR-proADM (-0.022 [-0.043 to -0.004]; P=0.043), MR-proANP (0.016 [-0.0034 to 0.035]; P=0.18), and C-terminal proendothelin 1 (-0.025 [-0.043 to -0.008]; P=0.00094]. In our large, population-based study, we identified MR-proADM and MR-proANP as circulating biomarkers of vascular function most strongly related to noninvasive measures of conduit artery and peripheral arterial performance. Whether determination of blood biomarkers helps to better understand vascular pathology and may provide prognostic information needs to be investigated in future studies.

Complement anaphylatoxin C3a as a novel independent prognostic marker in heart failure.

OBJECTIVES: The purpose of this study was to evaluate complement activation in a heart failure cohort. Based on their powerful biological activity, we hypothesized that the levels of anaphylatoxin C3a are related to pathological signs and outcomes in heart failure. DESIGN, SETTING AND PATIENTS: Complement activation products C3a and SC5b9 were determined in 182 consecutive CHF patients (single centre, prospective cohort study), with a left ventricular ejection fraction <45%. Mortality and re-hospitalisation due to the progression of CHF were assessed after a median follow-up of 14 months. INTERVENTIONS: None. RESULTS: In the univariate analysis, high level of anaphylatoxin C3a was significantly associated with clinical events (p < 0.0001), whereas SC5b9 showed a tendency of association (p = 0.094). In multivariable Cox analysis, adjusted for age, NT-proBNP, diastolic blood pressure, body mass index (BMI), haemoglobin and creatinine levels, C3a was a significant predictor of HF-related re-hospitalization or death (HR 1.189 per 1-SD increase, 95% CI 1.023-1.383), and of cardiovascular events or death (HR 1.302, CI 1.083-1.566). C3a was strongly associated with the presence of peripheral oedema, inflammatory markers (CRP, prealbumin, IL-6, sTNFRI, sTNFRII), heat-shock protein 70 levels and endothelial activation markers (von-Willebrand factor and endothelin-1). CONCLUSIONS: Results of the present study showed that complement activation is strongly linked to unfavourable outcomes in heart failure. High levels of anaphylatoxin C3a predicted re-hospitalization, cardiovascular events and mortality in adjusted survival model. Increased C3a levels were associated with biomarkers of acute-phase reaction, inflammation, cellular stress response, endothelial-cell activation and oedematous complications independently from disease severity.

Endothelial cell function in patients with hereditary angioedema: elevated soluble E-selectin level during inter-attack periods.

BACKGROUND: The bradykinin pathway in the pathomechanism of hereditary angioedema due to C1-inhibitor deficiency (henceforward "hereditary angioedema") has been thoroughly studied; however, much less is known about endothelial cell function. Enhanced endothelial cell permeability is obvious during edematous attacks, but not during inter-attack periods. Our knowledge about other endothelial characteristics is even more incomplete. OBJECTIVE: Therefore the aim of this study was to characterize endothelial cell function in hereditary angioedema patients during symptom-free, inter-attack periods. METHODS: We measured the serum levels of soluble E-selectin, endothelin-1, and von Willebrand factor along with collagen-binding activity in 49 hereditary angioedema patients and in 50 healthy controls. RESULTS: Endothelin-1 and von Willebrand factor level, as well as its collagen-binding activity, were similar in hereditary angioedema patients and in controls; however, we found elevated soluble E-selectin levels in the patients. Interestingly, soluble E-selectin concentration did not correlate with any of the inflammatory markers or smoking, and it is not the consequence of the known E-selectin/C1-inhibitor interaction (an analytical phenomenon). In a multiple logistic regression model, the difference in soluble E-selectin between hereditary angioedema patients and controls remained highly significant when adjusted for age, gender, smoking, C-reactive protein, and AB0 blood groups. CONCLUSION: These results demonstrate that in hereditary angioedema, the majority of endothelial functions are normal during inter-attack periods; however, soluble E-selectin levels are elevated. The higher soluble E-selectin plasma concentration is unlikely to result from inflammation; rather, it reflects enhanced shedding mechanisms.

Impaired physical quality of life in patients with diastolic dysfunction associates more strongly with neurohumoral activation than with echocardiographic parameters: quality of life in diastolic dysfunction.

BACKGROUND: Quality of life (QoL) is impaired in diastolic heart failure. Little is known about QoL in diastolic dysfunction (DD) without heart failure. METHODS: In the DIAST-CHF observational study, outpatients with risk factors for or a history of heart failure were included. In a cross-sectional analysis, we classified patients with preserved systolic function as having normal diastolic function (N, n = 264) or DD without (DD-, n = 957) or with (DD+, n = 321) elevated filling pressures according to echocardiography. Quality of life was evaluated by the Short Form 36 (SF-36) questionnaire. RESULTS: Short Form 36 physical function (SF-36-PF) was worse in DD+ (mean ± SD 67.2 ± 25.6) than in DD- (76.2 ± 22.7, P < .05) than in N (mean ± SD 81.1 ± 23.5, P < .01). Other physical dimensions and the physical component score were also lower in DD, whereas the mental component score did not differ. The SF-36-PF correlated weakly with echocardiographic indicators of diastolic function. In multivariate linear regression controlling for age, sex, body mass index, depressiveness as assessed by Patient Health Questionnaire 9, N-terminal probrain-type natriuretic peptide, and midregional proadrenomedullin (MR-proADM), individual echocardiographic parameters or grade of DD was not independently associated with SF-36-PF, whereas the presence of DD+ was. Both N-terminal probrain-type natriuretic peptide and MR-proADM were independently associated with SF-36-PF, with MR-proADM showing the stronger association. CONCLUSIONS: Physical dimensions of QoL are reduced in DD. Impaired SF-36-PF is only weakly associated with DD per se but rather seems to be contingent on the presence of elevated filling pressures. Biomarkers are more strongly and independently associated with SF-36-PF and may be more adequate surrogate markers of QoL in DD than echocardiographic measurements.

Serum soluble E-selectin and NT-proBNP levels additively predict mortality in diabetic patients with chronic heart failure.

BACKGROUND: Neuroendocrine activation with endothelial dysfunction is a key pathophysiological process in chronic heart failure (CHF). Although increased soluble E-selectin (sE-selectin) levels predict adverse events in several forms of cardiovascular disease, there are only scarce data on its predictive value in CHF. The aim of our study was to investigate whether sE-selectin is a useful predictor of mortality in CHF patients and whether its predictive power is additive to that of NT-proBNP. METHODS: Plasma levels of sE-selectin were measured by ELISA in 192 CHF patients with clinical systolic heart failure. The study population was followed up for 14.9 months on average; 46 patients died during this period. RESULTS: Levels of sE-selectin were significantly higher in non-surviving patients than in survivors (p = 0.005) and significantly correlated with the following inflammatory markers: CRP (r = 0.242, p = 0.001), TNF-α (r = 0.201, p = 0.005), TNF-RII (r = 0.207, p = 0.004), and IL-6 (r = 0.339, p < 0.0001). According to Cox regression analysis of the prediction power of sE-selectin for all-cause mortality, high sE-selectin levels independently and significantly predicted short-term mortality in CHF (HR 1.47, 95% CI 1.103-1.956). Furthermore, sE-selectin predicted mortality in CHF patients with concomitant diabetes mellitus, as well as simultaneously elevated sE-selectin and NT-proBNP levels additively predicted mortality. CONCLUSIONS: This study demonstrated a weak correlation of sE-selectin level with inflammatory markers and prediction of short-term mortality in diabetic CHF patients. Elevated serum sE-selectin levels and concomitantly increased NT-proBNP concentrations have additive predictive power in CHF. This suggests that parallel activation of various pathophysiological pathways confers increased risk of adverse outcome in CHF.

Midregional pro-atrial natriuretic peptide: a novel marker of myocardial fibrosis in patients with hypertrophic cardiomyopathy.

We aimed to determine the diagnostic performance of biomarkers in predicting myocardial fibrosis assessed by late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) in patients with hypertrophic cardiomyopathy (HCM). LGE CMR was performed in 40 consecutive patients with HCM. Left and right ventricular parameters, as well as the extent of LGE were determined and correlated to the plasma levels of midregional pro-atrial natriuretic peptide (MR-proANP), midregional pro-adrenomedullin (MR-proADM), carboxy-terminal pro-endothelin-1 (CT-proET-1), carboxy-terminal pro-vasopressin (CT-proAVP), matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1) and interleukin-8 (IL-8). Myocardial fibrosis was assumed positive, if CMR indicated LGE. LGE was present in 26 of 40 patients with HCM (65%) with variable extent (mean: 14%, range: 1.3-42%). The extent of LGE was positively associated with MR-proANP (r = 0.4; P = 0.01). No correlations were found between LGE and MR-proADM (r = 0.1; P = 0.5), CT-proET-1 (r = 0.07; P = 0.66), CT-proAVP (r = 0.16; P = 0.3), MMP-9 (r = 0.01; P = 0.9), TIMP-1 (r = 0.02; P = 0.85), and IL-8 (r = 0.02; P = 0.89). After adjustment for confounding factors, MR-proANP was the only independent predictor associated with the presence of LGE (P = 0.007) in multivariate analysis. The area under the ROC curve (AUC) indicated good predictive performance (AUC = 0.882) of MR-proANP with respect to LGE. The odds ratio was 1.268 (95% confidence interval 1.066-1.508). The sensitivity of MR-proANP at a cut-off value of 207 pmol/L was 69%, the specificity 94%, the positive predictive value 90% and the negative predictive value 80%. The results imply that MR-proANP serves as a novel marker of myocardial fibrosis assessed by LGE CMR in patients with HCM.

Assessment of inflammatory markers in patients with community-acquired pneumonia--influence of antimicrobial pre-treatment: results from the German competence network CAPNETZ.

BACKGROUND: There is almost no data about the influence of antimicrobial pre-treatment (APT) on levels of inflammatory markers in community acquired pneumonia (CAP). The aim of this study was to investigate the influence of APT on inflammatory markers in CAP. METHODS: 991 hospitalized patients (64.3±17.6 years, 61% male) with CAP were enrolled. In all patients procalcitonin (PCT), C-reactive protein (CRP), and leukocyte count (WBC) were determined. Patients were followed-up for 28 days for survival. RESULTS: 232 patients (23.4%) had APT, 759 had no APT. Patients without APT had significantly higher levels of PCT and WBC but not of CRP compared to those with APT. In patients without APT, survivors compared to non-survivors had lower values of PCT (0.20 ng/mL; 0.02-169.10 vs. 0.83 ng/mL; 0.04-516.30, p<0.0001), WBC (12.4×10(9)/L; 1.3-49.9 vs. 14.9×10(9)/L; 3.7-34.5, p=0.047) and CRP (107.0mg/mL; 0.3-567.0 vs. 143.5mg/mL; 5.0-589.0, p=0.006). However, in patients with APT, the values of PCT, WBC and CRP were not significantly different in survivors and non-survivors. Cox regression analysis confirmed that PCT, CRP and WBC were predictive for 28 day mortality in patients without APT but not in those with APT. CONCLUSIONS: PCT and WBC but not CRP levels are higher in patients without APT compared to those with APT. PCT, CRP and WBC are predictive for 28 days mortality exclusively in patients without APT. Interpretation of inflammatory parameters has to take into account possible APT.

Copeptin improves early diagnosis of acute myocardial infarction.

OBJECTIVES: Early identification of myocardial infarction in chest pain patients is crucial to identify patients at risk and to maintain a fast treatment initiation. BACKGROUND: The 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. METHODS: Between 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. RESULTS: Of 1,386 (66.4% male) enrolled patients, 299 (21.6%) had the discharge diagnosis of acute myocardial infarction, 184 (13.3%) presented with unstable angina, and in 903 (65.2%) an acute coronary syndrome could be excluded. Combined measurement of copeptin and TnT on admission improved the c-statistic from 0.84 for TnT alone to 0.93 in the overall population and from 0.77 to 0.9 in patients presenting within 3 h after chest pain onset (CPO) (p < 0.001). In this group the combination of copeptin with a conventional TnT provided a negative predictive value of 92.4%. CONCLUSIONS: In triage of chest pain patients, determination of copeptin in addition to troponin improves diagnostic performance, especially early after CPO. Combined determination of troponin and copeptin provides a remarkable negative predictive value virtually independent of CPO time and therefore aids in early and safe rule-out of myocardial infarction.

Pro-atrial natriuretic peptide and pro-vasopressin for predicting short-term and long-term survival in community-acquired pneumonia: results from the German Competence Network CAPNETZ.

BACKGROUND: Community-acquired pneumonia (CAP) is the most important clinical infection with a high long-term mortality rate. The aim of this study was to evaluate the value of biomarkers for the prediction of short-term and long-term mortality in CAP. METHODS: A total of 1740 patients of mean + or - SD age 60 + or - 18 years (45% female) with proven CAP were enrolled in the study. Mid-regional pro-atrial natriuretic peptide (MR-proANP), C-terminal pro-atrial vasopressin (CT-proAVP), procalcitonin, C-reactive protein, leucocyte count (WBC) and CRB-65 score were determined on admission. Patients were followed up for 180 days. RESULTS: MR-proANP and CT-proAVP levels increased with increasing severity of CAP, classified according to CRB-65 score. In patients who died within 28 and 180 days, median MR-proANP (313.9 vs 80.0 and 277.8 vs 76.0 pmol/l, each p<0.0001) and CT-proAVP (42.6 vs 11.2 and 33.2 vs 10.7 pmol/l, each p<0.0001) levels were significantly higher than the levels in survivors. In receiver operating characteristics analysis for survival at 28 and 180 days, the areas under the curves (AUCs) for CT-proAVP (0.84, 95% CI 0.82 to 0.86 and 0.78, 95% CI 0.76 to 0.80) and MR-proANP (0.81, 95% CI 0.79 to 0.83 and 0.81, 95% CI 0.79 to 0.83) were superior to the AUC of CRB-65 (0.74, 95% CI 0.71 to 0.76 and 0.71, 95% CI 0.69 to 0.74, p<0.05), procalcitonin, C-reactive protein and WBC. In multivariable Cox proportional hazards regression analyses adjusted for comorbidity and pneumonia severity, MR-proANP and CT-proAVP were independent and the strongest predictors of short-term and long-term mortality. CONCLUSIONS: MR-proANP and CT-proAVP are powerful tools for the prediction of short-term and long-term risk stratification of patients with CAP.

Relation of natriuretic peptides and midregional proadrenomedullin to cardiac chamber volumes by computed tomography in patients without heart failure: from the ROMICAT Trial.

BACKGROUND: Stress myocyte biomarkers are used prognostically in patients with cardiovascular disease. We examined associations between amino-terminal pro-B-type natriuretic peptide (NT-proBNP), midregional pro-A-type natriuretic peptide (MR-proANP), and midregional proadrenomedullin (MR-proADM) concentrations and cardiac chamber volumes in chest pain patients without heart failure by use of computed tomography (CT). METHODS: At the time of 64-slice CT scan, we acquired plasma and serum samples for these biomarkers from 346 patients [mean (SD) age 53 (12) years, 65% men]. Left atrial volume (LAV) and left ventricular volumes at end-diastole (LVEDV) and end-systole (LVESV) were measured and indexed to body surface area (LAVI, LVEDI, LVESI). RESULTS: Concentrations of both natriuretic peptides were correlated with LAV and LAVI (r = 0.19-0.32, all P

Levels of von Willebrand factor antigen and von Willebrand factor cleaving protease (ADAMTS13) activity predict clinical events in chronic heart failure.

Decreased activity of ADAMTS13, the von Willebrand factor (VWF) cleaving protease, was recently reported in cardiovascular diseases and in hepatic failure. Chronic heart failure (CHF) is characterised by abnormalities of left ventricular function accompanied by the failure of the liver and dysregulation of endothelial activation. Therefore, the aim of our study was to measure ADAMTS13 activity in CHF, and determine the prognostic value of VWF and ADAMTS13 on major clinical events in CHF. ADAMTS13 activity (measured by FRETS-VWF73 substrate) was decreased in CHF (n = 152, left ventricular ejection fraction <45%), and it correlated negatively with B-type natriuretic peptide (BNP) NYHA (New York Heart Association) classes, markers of synthetic capacity of the liver and endothelial dysfunction (all p < 0.005). Both, high VWF:Ag levels (hazard ratio [HR] 1.52, 95% confidence interval [CI] 1.189-1.943), and low ADAMTS13/VWF:Ag ratios (HR 0.70, 95% CI 0.58-0.84) independently and significantly predicted short-term (1 year follow-up) clinical adverse events in heart failure (HF). Decreased activity of ADAMTS13 with concomitant high VWF:Ag levels is a significant independent predictor of clinical events in CHF. The levels of the two molecules may integrate the impaired synthetic capacity of the liver and the disturbed endothelial regulation and can therefore be a useful tool to predict clinical events in CHF.

Inflammatory parameters predict etiologic patterns but do not allow for individual prediction of etiology in patients with CAP: results from the German competence network CAPNETZ.

BACKGROUND: Aim of this study was to evaluate the correlation of inflammatory markers procalcitonin (PCT), C-reactive protein (CRP) and leukocyte count (WBC) with microbiological etiology of CAP. METHODS: We enrolled 1337 patients (62 +/- 18 y, 45% f) with proven CAP. Extensive microbiological workup was performed. In all patients PCT, CRP, WBC and CRB-65 score were determined. Patients were classified according to microbial diagnosis and CRB-65 score. RESULTS: In patients with typical bacterial CAP, levels of PCT, CRP and WBC were significantly higher compared to CAP of atypical or viral etiology. There were no significant differences in PCT, CRP and WBC in patients with atypical or viral etiology of CAP. In contrast to CRP and WBC, PCT markedly increased with severity of CAP as measured by CRB-65 score (p < 0.0001). In ROC analysis for discrimination of patients with CRB-65 scores > 1, AUC for PCT was 0.69 (95% CI 0.66 to 0.71), which was higher compared to CRP and WBC (p < 0.0001). CRB-65, PCT, CRP and WBC were higher (p < 0.0001) in hospitalised patients in comparison to outpatients. CONCLUSION: PCT, CRP and WBC are highest in typical bacterial etiology in CAP but do not allow individual prediction of etiology. In contrast to CRP and WBC, PCT is useful in severity assessment of CAP.

C-terminal provasopressin (copeptin) in patients with community-acquired pneumonia--influence of antibiotic pre-treatment: results from the German competence network CAPNETZ.

BACKGROUND: Recently, C-terminal provasopressin (copeptin) turned out to be predictive for mortality in community-acquired pneumonia (CAP). The aim of this study was to evaluate the influence of antibiotic pre-treatment on copeptin levels in CAP. METHODS: We enrolled 370 hospitalized patients (66 +/- 17 years; 42% females) with proven CAP. Venous blood samples were collected at the time of inclusion into the study and as soon as possible after the diagnosis of CAP. Copeptin (B.R.A.H.M.S. AG, Henningsdorf, Germany) levels were determined in venous blood on admission. RESULTS: Eighty-five patients had antibiotic pre-treatment and 285 patients did not. Copeptin levels increased with increasing severity of CAP in patients without antibiotic pre-treatment but not in patients with antibiotic pre-treatment. Patients with prior antibiotic treatment showed significantly lower levels of copeptin [median (interquartile range): 12.8 (5.3-22.6) versus 20.8 (11.1-37.8) pmol/L, P < 0.0001] and procalcitonin [0.15 (0.07-0.38) versus 0.27 (0.10-1.52) ng/mL, P = 0.0003], but not C-reactive protein [113 (46-229) versus 122 (49-231) mg/mL, not significant] and leucocytes [12.2 x 10(3) (8.1 x 10(3)-15.4 x 10(3)) versus 12.5 x 10(3) (9.4 x 10(3)-16.3 x 10(3)) cells/mm(3), not significant] compared with those without antibiotic pre-treatment. CONCLUSIONS: Copeptin serum levels are higher in patients without antibiotic pre-treatment compared with those with antibiotic pre-treatment. Copeptin serum levels increase with an increasing severity of CAP in patients without, but not in patients with, antibiotic pre-treatment. Thus, antibiotic pre-treatment has to be taken into account for the correct interpretation of copeptin levels in CAP.

Homogeneous time-resolved fluoroimmunoassay for the measurement of midregional proadrenomedullin in plasma on the fully automated system B.R.A.H.M.S KRYPTOR.

OBJECTIVES: Evaluate the first automated assay measuring a mid regional fragment of the proadrenomedullin (MR-proADM). DESIGN AND METHODS: B.R.A.H.M.S MR-proADM KRYPTOR is a homogeneous assay. RESULTS: In 144 healthy individuals, MR-proADM mean (SD) was measured at 0.37 nmol/L (0.09). High correlation with the manual assay, B.R.A.H.M.S MR-proADM LIA, was found on 281 samples from patients suffering from community acquired pneumonia (correlation coefficient 0.97). CONCLUSIONS: This fast assay can be used in low respiratory tract infections.