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Background: The introduction of high-sensitivity cardiac troponin (hs-cTn) assays allows the assessment of clinical decision values below the 99th percentile., Methods: Final diagnosis and one-year mortality were adjudicated in a multicenter, prospective cohort of 1181 patients presenting with acute chest pain to the emergency department. Hs-cTnT (Roche) and cTnI-ultra (Siemens) were measured in a blinded fashion., Results: At presentation hs-cTnT and cTnI-ultra were below the limit of blank (LOB) in 201 (17%) and 549 (47%) patients, below the 75th percentile in 379 (32%) and 623 (53%) patients, below the 95th percentile in 603 (51%) and 808 (68%), and below the 99th percentile in 748 (63%) and 913 (77%), respectively. Sensitivities for the diagnosis of AMI were 100.0% and 96.8% respectively for hs-cTnT and cTnI-ultra (LOB as cut-off value), 99.5% and 96.2% (75th percentile), 96.8% and 93.0% (95th percentile), and 94.1% and 88.1% (99th percentile). The proportion of patients correctly classified as having or not AMI increased from 32.9% (LOB as cut-off value) to 47.8% (75th percentile), 65.9% (95th percentile) and 77.3% (99th percentile) for hs-cTnT and from 61.2% to 67.3%, 81.9% and 89.3% respectively for cTnI-ultra. At 1 year, all-cause mortality was very low and similar for patients below all of these cut-off levels (between 0.7% and 1.5%, p=0.748 for all-groups comparison)., Conclusion: cTn should be considered as a continuous variable. Decision values below the 99th percentile (e.g. the 75th percentile) are associated with a very high NPV for the diagnosis of AMI, but have a lower accuracy than the 99th percentile., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background: Exercise is associated with changes in circulating B-type natriuretic peptide (BNP) and N-terminal-proBNP (NT-proBNP). However, the biological relevance of this phenomenon is poorly examined. We sought to assess determinants of absolute (Δ) and relative (Δ%) exercise-induced changes in BNP and NT-proBNP., Methods: BNP (n = 418) and NT-proBNP (n = 478) at rest and peak exercise were measured in patients undergoing symptom-limited cycle ergometer tests. Multivariate logistic regression was performed to identify predictors of high ΔBNP/ΔNT-proBNP and high ΔBNP/Δ%NT-proBNP defined as their highest quartiles (Q4)., Results: The median (interquartile range) ΔBNP and ΔNT-proBNP was 12 (0-28) pg/ml and 7 (2-21) pg/ml respectively, and Δ%BNP and Δ%NT-proBNP was 21 (0-46) % and 7 (3-12) % respectively. Higher BNP [odds ratio (OR) 3.92 per ln unit; p < 0.001] or NT-proBNP [OR 4.88 per ln unit; p<0.001] at rest was the strongest predictor of ΔBNP in Q4 (≥ 28 pg/ml) or ΔNT-proBNP in Q4 (≥ 21 pg/ml). In contrast, higher maximal work rate expressed as the percentage of the predicted value (OR 1.015 per %; p = 0.007) was the only independent predictor of Δ%BNP in Q4 (≥ 46%), and lower resting heart rate (OR 0.97 per bpm; p = 0.001) and lower age (OR 0.95 per year; p = 0.001) were the only independent predictors of Δ%NT-proBNP in Q4 (≥ 12%)., Conclusions: Higher ΔBNP and ΔNT-proBNP primarily reflected higher BNP and NT-proBNP plasma levels at rest. In contrast, higher Δ%BNP and Δ%NT-proBNP were associated with several prognostically favorable features, indicating that higher Δ%BNP and Δ%NT-proBNP may be markers of health rather than disease., (Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.)

Objectives: This study aimed to examine the influence of history of heart failure (HF) on circulating levels, diagnostic accuracy and prognostic value of B-type natriuretic peptide (BNP) in patients presenting with all cause dyspnea at the emergency department., Background: BNP has been shown to be very helpful in diagnosis and prognosis of HF. Due to chronically elevated cardiac filling pressures, patients with a history of HF might have higher BNP levels and therefore diagnostic and prognostic properties of BNP may be affected., Methods: We analyzed circulating levels, diagnostic accuracy and prognostic value of BNP in 388 patients without a previous history of HF and compared these to data to 64 patients with a history of HF included in the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) Study., Results: Baseline BNP levels were higher in patients with a history of HF (median 814 pg/ml [353-1300 pg/ml] vs. 216 pg/ml [45-801 pg/ml], p<0.001). Diagnostic accuracy of BNP to identify HF was comparable in patients with (AUC=0.804; 95% CI 0.628-0.980) and in patients without history of HF (AUC=0.883; 95% CI 0.848-0.919, p=0.389). Prognostic ability of BNP to predict one-year mortality was lower in overall patients with history of HF (AUC=0.458; 95%CI 0.294-0.622) compared to patients without history of HF (AUC=0.710; 95% CI 0.653-0.768, p<0.05)., Conclusions: In patients with history of HF, BNP levels retain diagnostic accuracy. Ability to predict one-year mortality was decreased in unselected patients, but not in patients with acute HF-induced dyspnea., (Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.)

Background: B-type natriuretic peptide (BNP) is a predictor of death in patients with lung disease. We hypothesised that in patients with lung disease, BNP and N-terminal-pro-B-type natriuretic peptide (NT-proBNP) could predict a peak VO(2)<15 ml/kg/min, which is the proposed cut-off indicating an increased risk of perioperative complications during lung resection surgery., Methods: BNP and NT-proBNP were measured in 85 patients with a variety of pulmonary pathologies undergoing cardiopulmonary exercise testing and fulfilling criteria for appropriate effort., Results: BNP [69 (42-270) vs. 33 (15-65)pg/ml; p=0.001] and NT-proBNP [290 (129-1075) vs. 65 (21-129)pg/ml; p<0.001] were higher in patients with peak VO(2)<15 ml/kg/min (n=27) as compared to those with peak VO(2)> or =15 ml/kg/min (n=58). Apart from the forced expiratory volume within the first second (FEV(1)), body mass index (BMI), diabetes, and the alveolo-arterial oxygen pressure difference [D(A-a)O(2); only in the BNP model], BNP or NT-proBNP respectively were independent predictors of peak VO(2)<15 ml/kg/min. The areas under the receiver-operator-characteristics curve (AUC) for BNP and NT-proBNP to predict a peak VO(2)<15 ml/kg/min were 0.73 and 0.80 respectively. A five-item (BNP) or four-item (NT-proBNP) score including BMI, FEV(1), diabetes, D(A-a)O(2), and BNP/NT-proBNP had an AUC of 0.87 and 0.88 respectively for the prediction of peak VO(2)<15ml/kg/min., Conclusions: In patients with lung disease, BNP or NT-proBNP is independently associated with low peak VO(2). A simple score based on spirometry, blood gases and BNP or NT-proBNP has a high accuracy for the prediction of a peak VO(2)<15 ml/kg/min.

The utility of B-type natriuretic peptide (BNP) testing in patients with atrial fibrillation (AF) is poorly defined. We analyzed patients (n=452) included in the BNP for Acute Shortness of Breath Evaluation (BASEL) study. Patients were randomly assigned to a diagnostic strategy with or without the use of BNP. Ninety-nine patients presented with AF (n=48 BNP group; n=51 control group). Although comparable with respect to gender and cardiopulmonary comorbidity, patients with AF were older and more often had heart failure as the cause of dyspnea. In addition, patients with AF had higher in-hospital mortality (13% versus 6%, P=0.012). The use of BNP significantly reduced time to discharge (BNP group median 8 days [1-16] versus 12 days [IQR 4-21] control group; P=0.046) in patients with AF. Initial total treatment costs (median) were $4239 [769-7422] in the BNP group and $5940 [4024-10848] in the control group (P=0.041). These benefits were maintained after 90 days: patients in the BNP group had spent fewer days in hospital (10 days [2-21] versus 15 days [IQR 9-27]; P=0.022) and induced lower total treatment costs ($4790 [1260-9387] versus $7179 [4311-13173]; P=0.016). In conclusion, the use of BNP seems to improve the management of patients with AF presenting with dyspnea.

Background: The role of the arginine-vasopressin (AVP) system in the response to myocardial ischemia is unclear. Copeptin, the C-terminal part of the AVP prohormone is secreted stoichiometrically with AVP., Methods: A total of 253 consecutive patients with suspected myocardial ischemia referred for rest/ergometry myocardial perfusion single-photon emission computed tomography (SPECT) were enrolled. We evaluated the response of copeptin during exercise and determined whether measurement of copeptin may be helpful in the detection of myocardial ischemia., Results: Myocardial ischemia on perfusion images was detected in 127 patients (50%). Median copeptin levels increased significantly with exercise in patients with ischemia as well as in patients without ischemia (from 3.8 [IQR 2.8-6.6] to 12.3 [IQR 5.2-39.6] pmol/l, P<0.001; and from 3.6 [IQR 2.6-5.7] to 10.8 [IQR 5.0-24.5] pmol/l, P<0.001). Median exercise-induced changes in copeptin (Deltacopeptin) were similar in both groups (7.7 versus 5.1 pmol/l, P=0.150). The area under the ROC curve for the ability of Deltacopeptin to detect myocardial ischemia was 0.552., Conclusions: Copeptin levels increased threefold with exercise, irrespective of the presence or absence of myocardial ischemia. Therefore, myocardial ischemia does not seem to be a major trigger of the AVP system. Measurement of copeptin does not seem helpful in the detection of exercise-induced myocardial ischemia.