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Aims Gamma-glutamyltransferase (GGT) has been recognized as a cardiovascular risk factor, and its highest molecular weight fraction [big GGT (b-GGT)] is found in vulnerable atherosclerotic plaques. We explored the relationship between b-GGT, computed tomography findings, and long-term outcomes in the general population. Methods and results Between May 2010 and October 2011, subjects aged 45–75 years living in a Tuscan city and without known cardiac disease were screened. The primary endpoint was a composite of cardiovascular death or acute coronary syndrome requiring urgent coronary revascularization. Gamma-glutamyltransferase fractions were available in 898 subjects [median age 65 years (25th–75th percentile 55–70), 46% men]. Median plasma GGT was 20 IU (15–29), and b-GGT was 2.28 (1.28–4.17). Coronary artery calcium (CAC) score values were 0 (0–60), and the volume of pro-atherogenic epicardial fat was 155 mL (114–204). In a model including age, sex, low-density lipoprotein (LDL) cholesterol, current or previous smoking status, hypertension, diabetes, obesity, b-GGT independently predicted epicardial fat volume (EFV) (r = 0.162, P < 0.001), but not CAC (P = 0.198). Over a 10.3-year follow-up (9.6–10.8), 27 subjects (3%) experienced the primary endpoint. We evaluated couples of variables including b-GGT and a cardiovascular risk factor, CAC or EFV. Big GGT yielded independent prognostic significance from age, LDL cholesterol, current or previous smoking status, hypertension, diabetes, obesity, but not CAC or EFV. Conversely, GGT predicted the primary endpoint even independently from CAC and EFV. Conclusion Big GGT seemed at least as predictive as the commonly available GGT assay; therefore, the need for b-GGT rather than GGT measurement should be carefully examined.

The most recent international guidelines recommend the measurement of cardiac troponin I (cTnI) and cardiac troponin T (cTnT) using high-sensitivity methods (hs-cTn) for the detection of myocardial injury and the differential diagnosis of acute coronary syndromes. Myocardial injury is a prerequisite for the diagnosis of acute myocardial infarction, but also a distinct entity. The 2018 Fourth Universal Definition of Myocardial Infarction states that myocardial injury is detected when at least one value above the 99th percentile upper reference limit is measured in a patient with high-sensitivity methods for cTnI or cTnT. Not infrequently, increased hs-cTnT levels are reported in patients with congenital or chronic neuromuscular diseases, while the hs-cTnI values are often in the normal range. Furthermore, some discrepancies between the results of laboratory tests for the two troponins are occasionally found in individuals apparently free of cardiac diseases, and also in patients with cardiac diseases. In this review article, authors discuss the biochemical, pathophysiological and analytical mechanisms which may cause discrepancies between hs-cTnI and hs-cTnT test results.

Background Postexercise release of cardiac troponin (cTn) is a well-known phenomenon, although the influence of various confounders remains unclear. The aim of this critical review was to analyze the postexercise release of cTn according to age, sex, different types of sport, exercise intensity and duration, and training level. Data sources A literature search was performed within the National Library of Medicine using the following keywords: cTn, peak, release, and exercise. The search was further refined by adding the keywords athletes, children/adolescents, and sport. Main results For final analysis, 52 studies were included: 43 adult studies, 4 pediatric studies, and 5 with a mixed population of adults and children. Several studies have investigated the kinetics of cTn response after exercise with different biomarkers. The current evidence suggests that sport intensity and duration have significant effects on postexercise cTn elevation, whereas the influence of the type of sport, age, and sex have been not completely defined yet. Most data were obtained during endurance races, whereas evidence is limited (or almost absent), particularly for mixed sports. Data on young adults and professional athletes are limited. Finally, studies on women are extremely limited, and those for non-White are absent. Conclusions Postexercise release of cTn can be observed both in young and master athletes and usually represents a physiological phenomenon; however, more rarely, it may unmask a subclinical cardiac disease. The influence of different confounders (age, sex, sport type/intensity/duration, and training level) should be better clarified to establish individualized ranges of normality for postexercise cTn elevation.

Bakground The aim of this study was to evaluate both analytical characteristics and clinical results of a new chemiluminescent method for the measurement of cardiac troponin I (cTnI), named VITROS ® High Sensitivity Troponin I Assay, using the VITROS® 3600 automated platform. The results found with this new method were compared to those observed with hs-cTnI ARCHITECT and ECLIA hs-cTnT ELECSYS methods. Methods For evaluation of analytical performance and comparison of clinical results, plasma samples (lithium-heparin), were collected from apparently healthy subjects and patients with cardiovascular diseases. Results The hs-cTnI VITROS method showed values for limit of blank (LoB 0.33 ng/L), limit of detection (LoD, 0.91 ng/L), limit of quantifications at 20% (LoQ 20% CV, 1.82 ng/L), and 10% (LoQ 10% CV, 4,74 ng/L), which are comparable to those previously reported for other hs-cTnI methods. Moreover, the clinical results of the hs-cTnI VITROS method were found to be closely correlated to those of hs-cTnI ARCHITECT (R = 0,9883, N = 198) and ECLIA hs-cTnT Elecsys (R = 0,9704, N = 293) methods. Conclusions The hs-cTnI VITROS method shows analytical performance comparable to other cTnI and cTnT assay. The results of this study confirm that there are significant systematic differences among hs-cTnI methods. Further multicenter studies using larger reference populations are needed in order to obtain a better estimation, especially of the 99° percentile URL values categorized for sex and age of hs-cTnI and hs-cTnT methods.

Background The study aim was to evaluate and compare analytical performances and clinical results of ADVIA BNP and PBNP methods using the Centaur XPT platform with those of Access BNP, using the DxI platform and the ECLIA NT-proBNP method, using the Cobas e411 platform, respectively. Methods Limits of blank (LoB), detection (LoD) and quantitation (LoQ) at 20% CV and 10% CV were evaluated according to international standardized protocols. The analytical parameters were assessed throughout a 90-working-day period using three curve calibrations. Results LoB, LoD and LoQ at 20% CV and 10% values of the ADVIA BNP method were 1.0 ng/L, 2.0 ng/L, 3.7 ng/L and 10.2 ng/L, respectively; while those of the ADVIA PBNP method were 1.3 ng/L, 3.0 ng/L, 9.7 ng/L and 22.3 ng/L, respectively. The ADVIA BNP and PBNP methods were able to measure the clinical decision values suggested by international guidelines for diagnosis of heart failure (HF) with an imprecision ≤6%. BNP concentrations measured with the ADVIA and Access methods showed a close linear regression (R=0.9923, n=200); a close linear regression was also found between NT-proBNP concentrations measured with the ADVIA and ECLIA methods (R=0.9954, n=202). However, the ADVIA method measured significantly lower BNP values than the Access method (on average −20.9%), while ADVIA PBNP method measured significantly higher NT-proBNP concentrations than the ECLIA method (on average +17.8%). Conclusions Analytical performances of the BNP and PBNP ADVIA methods are well in accordance with the quality specifications required by international guidelines for diagnosis and follow-up of patients with HF.

Introduction: The increase of the anti-inflammatory CD163highHLA-DRlow blood monocyte subset is one of the mechanisms dampening inflammation during cardiac surgery with cardiopulmonary bypass. We evaluated the effect of two different anesthetic protocols, intravenous Propofol infusion or Sevoflurane-gas administration, on the perioperative frequency of this subset. Methods: Blood from patients (Propofol = 11, Sevoflurane = 13) undergoing minimally invasive mitral valve surgery was drawn preoperatively (T1), before declamping (T2), at 6 (T3), 24 (T4), 48 (T5), and 72 hours (T6) after declamping. C-reactive protein, haptoglobin, and lactate dehydrogenase were measured. A hemolytic index, as C-reactive protein/haptoglobin ratio, was introduced. Monocyte expression of HLA-DR, CD163, and the CD163highHLA-DRlow subset fraction was quantified by flow cytometry. Baseline-referred variations of plasmatic and cellular data at T2 were normalized for clamping times. Subsequent time-point variations were normalized for the final cardiopulmonary bypass times. Results: Variations of hemolytic index and lactate dehydrogenase were higher with Propofol at T3 (p = 0.004 and p = 0.02, respectively) when compared with Sevoflurane. At T2, the down-modulation of CD163 was higher with Propofol (p = 0.005). Starting from T3, the up-regulatory trend of CD163 was basically higher with Propofol, although not significantly. Propofol induced higher increments of HLA-DR low fractions, at T2 (p = 0.04) and, to a lesser extent, at T4 (p = 0.06). Starting from T3, the CD163highHLA-DRlow subset variations were higher with Propofol, especially at T4 and T6. Conclusion: Propofol seems to induce a higher postoperative fraction of the CD163highHLA-DRlow monocyte subset. This could represent either a compensatory mechanism dampening the higher inflammatory condition observed with Propofol at T2 or a consequence of a higher postoperative Propofol-induced hemolysis.

Background The Italian Society of Clinical Biochemistry (SIBioC) and the Italian Section of the European Ligand Assay Society (ELAS) have recently promoted a multicenter study (Italian hs-cTnI Study) with the aim to accurately evaluate analytical performances and reference values of the most popular cTnI methods commercially available in Italy. The aim of this article is to report the results of the Italian hs-cTnI Study concerning the evaluation of the 99th percentile URL and reference change (RCV) values around the 99th URL of the Access cTnI method. Materials and methods Heparinized plasma samples were collected from 1306 healthy adult volunteers by 8 Italian clinical centers. Every center collected from 50 to 150 plasma samples from healthy adult subjects. All volunteers denied the presence of chronic or acute diseases and had normal values of routine laboratory tests (including creatinine, electrolytes, glucose and blood counts). An older cohort of 457 adult subjects (mean age 63.0 years; SD 8.1 years, minimum 47 years, maximum 86 years) underwent also ECG and cardiac imaging analysis in order to exclude the presence of asymptomatic cardiac disease. Results and conclusions The results of the present study confirm that the Access hsTnI method using the DxI platform satisfies the two criteria required by international guidelines for high-sensitivity methods for cTn assay. Furthermore, the results of this study confirm that the calculation of the 99th percentile URL values are greatly affected not only by age and sex of the reference population, but also by the statistical approach used for calculation of cTnI distribution parameters.

Background: Few studies, and with conflicting results, have evaluated the potential effects of iodinated contrast media on children's thyroid function. Objective: To investigate the effects of iodinated contrast medium on thyroid function in neonates, infants and young children with congenital heart disease undergoing cardiac computed tomography (CT). Materials and methods: We retrospectively evaluated 10 neonates (group 1) and 23 infants and young children (group 2) without thyroid or renal disease for serum levels of thyroid-stimulating hormone, free triiodothyronine and free thyroxine before contrast-enhanced cardiac CT, 48 h after CT and at discharge from the hospital. Cardiac CT was performed with intravenous administration of 1.14±0.17 mL/kg of body weight of iopromide (containing 370 mg of iodine/mL). Results: Group 1 had a reduction of thyroid-stimulating hormone from baseline to 48 h post injection (P=0.002). Group 2 had a reduction of thyroid-stimulating hormone median levels from baseline to 48 h post injection and an increase from 48 h to discharge (P=0.0005 and P=0.0001, respectively). Conclusion: Intravenous iodinated contrast medium in children with congenital heart disease caused transient thyroid-stimulating hormone decrease 48 h after CT, with thyroid-stimulating hormone returning to normal range at discharge.

noBackground & Objectives: The postoperative Low T3 syndrome has been considered as a possible source of reduced myocardial contractility, resulting in increased mortality after CABG. Effect of preoperative Low T3 has not been well studied in patients undergoing CABG surgery. Aim of our study is to evaluate effect of preoperative Low T3 syndrome in patients undergoing CABG surgery.Materials & Methods: Six hundred and six patients undergoing CABG were included in this prospective study. The impact of the base-line FT3 concentration and of preoperative low T3 syndrome on the risk of postoperative low cardiac output and hospital death was analyzed.Results: Fifteen patients (2.3%) postoperatively and 159 (26.2%) developed major complications. At univariate analysis a reduced EF, the presence of peripheral vascular disease, the NYHA class, the surgical urgency, the aortic cross-clamp time, the CPB time and the FT3 concentration at admission were significantly associated with low CO and higher mortality. At multivariate analysis, the CPB time, an emergency procedure, a reduced LVEF, and the fT3 concentration were independently related to the development of low CO. However, in multivariate analysis low EF, and the fT3 concentration were the only predictors of hospital death.Conclusion: We conclude that preoperative low EF and low T3 syndrome independently causes low cardiac output and higher mortality in patients undergoing CABG. Therefore, all patients undergoing CABG should be evaluated for low T3 syndrome and patients with low T3 syndrome should be considered at increased risk. Appropriate preoperative T3 replacement therapy could decrease the postoperative complications in patients undergoing CABG.JCMS Nepal. 2015; 11(2):1-7

Background:The study aim was to evaluate and compare the analytical performance of the new chemiluminescent immunoassay for cardiac troponin I (cTnI), called Access hs-TnI using DxI platform, with those of Access AccuTnI+3 method, and high-sensitivity (hs) cTnI method for ARCHITECT platform.Methods:The limits of blank (LoB), detection (LoD) and quantitation (LoQ) at 10% and 20% CV were evaluated according to international standardized protocols. For the evaluation of analytical performance and comparison of cTnI results, both heparinized plasma samples, collected from healthy subjects and patients with cardiac diseases, and quality control samples distributed in external quality assessment programs were used.Results:LoB, LoD and LoQ at 20% and 10% CV values of the Access hs-cTnI method were 0.6, 1.3, 2.1 and 5.3 ng/L, respectively. Access hs-cTnI method showed analytical performance significantly better than that of Access AccuTnI+3 method and similar results to those of hs ARCHITECT cTnI method. Moreover, the cTnI concentrations measured with Access hs-cTnI method showed close linear regressions with both Access AccuTnI+3 and ARCHITECT hs-cTnI methods, although there were systematic differences between these methods. There was no difference between cTnI values measured by Access hs-cTnI in heparinized plasma and serum samples, whereas there was a significant difference between cTnI values, respectively measured in EDTA and heparin plasma samples.Conclusions:Access hs-cTnI has analytical sensitivity parameters significantly improved compared to Access AccuTnI+3 method and is similar to those of the high-sensitivity method using ARCHITECT platform.

Background Diagnosis and treatment of acute kidney injury (AKI) is often delayed in children after cardiac surgery due to the lack of an early biomarker of renal damage. Our aim was to evaluate the diagnostic accuracy of plasma cystatin-C as an early biomarker of AKI and its prognostic value in pediatric cardiac surgery. Methods Cystatin-C and creatinine were measured pre-operatively and at 2–6–12 h post-surgery. The primary outcome was: AKI (defined as an increase of ≥ 1.5 of plasma creatinine from baseline) and a composite marker, including major complications and/or extubation time > 15 days. Risk was evaluated using Cox proportional hazards regression analysis, considering some continuous predictors in the basal model (i.e., age, body surface area and Aristotle-score) to which cystatin-C peak values were added. Discrimination, calibration, and reclassification tests were also performed. Results 248 children (140 males) undergoing cardiac surgery (median age 6.5 months; IQR: 1.7–40.1 months; range 0–17 years) have been enrolled. Post operatory Cystatin-C values were found to be an early diagnostic marker of AKI showing the best area under the ROC curve value (AUC) at 12 h (0.746, CI 95% 0.674–0.818). In the multivariable analyses, peak cystatin-C values showed a significant hazard ratio (HR = 2.665, CI 95% 1.750–4.059, p < 0.001). Finally, post operatory cystatin-C at 12 h significantly improved the AUC (p = 0.017) compared to basal model, resulting a net gain in reclassification proportion (NRI = 0.417, p < 0.001). Conclusions Our data show that cystatin-C should be considered an early biomarker of AKI, improving the risk prediction for complicated outcome in pediatric cardiac surgery.

There is strong clinical and experimental evidence that altered thyroid homeostasis negatively affects survival in cardiac patients, but a negative effect of the low triiodothyronine (T3) syndrome on the outcome of coronary artery bypass grafting (CABG) has not been demonstrated. This study was designed to evaluate the prognostic significance of low T3 syndrome in patients undergoing CABG.The thyroid profile was evaluated at hospital admission in 806 consecutive CABG patients. Known thyroid disease, severe systemic illness, and use of drugs interfering with thyroid metabolism were considered exclusion criteria. The effect of the baseline free T3 (fT3) concentration and of preoperative low T3 syndrome (fT32.23 pmol/L) on the risk of low cardiac output (CO) and death was analyzed in a logistic regression model.There were 19 (2.3%) deaths, and 64 (7.8%) patients experienced major complications. After univariate analysis, fT3, low T3, New York Heart Association class greater than II, low left ventricular ejection fraction (LVEF), and emergency were associated with low CO and hospital death. History of atrial fibrillation, cardiopulmonary bypass time, and peripheral vascular disease were associated only with low CO. At multivariate analysis, only fT3, low T3, emergency, and LVEF were associated with low CO, and fT3 (odds ratio, 0.172, 95% confidence interval, 0.078 to 0.379; p0.0001) and LVEF (odds ratio, 0.934, 95% confidence interval, 0.894 to 0.987; p = 0.03) were the only independent predictors of death.Our study demonstrates that low T3 is a strong predictor of death and low CO in CABG patients. For this reason, the thyroid profile should be evaluated before CABG, and patients with low T3 should be considered at higher risk and treated accordingly.

Background: Oxidative stress is crucial in the pathogenesis of atherosclerosis and acute myocardial infarction (AMI). Under the generic terms &ldquo, oxidative stress&rdquo, (OS), many biomarkers belonging to different pathways have been proposed. Aim: To compare the levels of recently proposed OS-related parameters in acute coronary syndromes (ACS) and stable coronary artery disease (CAD), to evaluate their effectiveness as additive risk or illness indicators of stable and acute ischemic events, and their response over time during the course of AMI. Methods: 76 ACS, 77 CAD patients, and 63 controls were enrolled in the study. Different OS-related biomarkers, including reactive oxygen metabolites (ROM), the total antioxidant capacity (OXY), nitrite/nitrate (final nitric oxide products, NOx), and Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), were evaluated. Moreover, time response during AMI course (admission, and 6, 12, 18, 24, 36, and 48 hours after, T0-T6, respectively) and correlation with traditional cardiovascular (CV) risk factors (age, gender, hypertension, diabetes mellitus, dyslipidemia, smoking habit) were also assessed. Results: Over time, ROM progressively increased while OXY and NOx decreased. Kinetics of LOX-1 during AMI shows that this biomarker boosts early during the acute event (T1 and T2) and then progressively decreases, being significantly lower from T0 to T6. Different OS-related biomarkers were differentially associated with CV risk factors and CAD or ACS presence. Conclusion: Differences in OS-related biomarkers (between groups, according to the response over time during AMI, and to the presence of CV risk factors) confirmed OS involvement in the transition from healthy status to stable CAD and ACS, although evidencing the heterogeneous nature of redox processes. In future, a multi-marker panel including different biomarkers and pathways of oxidative stress could be evaluated as an additive tool to be used in the CV prevention, diagnosis, patient stratification, and treatment.

New biomarkers potentially improve clinical management of cardiovascular disease, but there are gaps in understanding their role during childhood. Adiponectin regulates metabolism and exerts anti-inflammatory/anti-atherogenic effects. The aim of the study was to evaluate circulating levels of adiponectin during postnatal growth and its relationship with Brain Natriuretic Peptide (BNP) in healthy children, a marker of cardiac function known to be increased in childhood.Plasma adiponectin and BNP were measured in 131 healthy children divided into: 43 newborns (0-3 days), 29 neonates (4-30 days), 25 infants (1-12 months) and 34 children (1-12 years). A group of 33 healthy adult subjects (25-60 years) was also studied. Plasma adiponectin in the 131 children resulted significantly higher compared to adult subjects (p0.0001). The time-course of adiponectin suggests the design of three age-based intervals: the first until 1 month of age (median 29.07 μg/mL, 11.61-47.01 μg/mL 5°-95° percentiles), the second between 1 and 12 months of age (21.66 μg/mL, 8.83-59.81 μg/mL) and the third for age up to 12 years (13.81 μg/mL, 4.10-28.57 μg/mL). Both adiponectin and BNP exhibited the same trend of a progressive decrease during growth, showing a significant relationship (Spearman's rho = 0.403, p0.0001).Adiponectin plasma levels in a healthy pediatric population vary as a function of age. Three reference intervals for adiponectin in pediatric subjects have been indicated. The relationship between adiponectin and BNP suggests that the age-dependent profile of circulating adiponectin could also be due to BNP.

Background The aim of this study is to evaluate whether it is possible to reduce the between-methods variability of troponin I (cTnI) immunoassays using mathematical algorithms calculated from the results of both patients' samples and quality control materials distributed in an external quality assessment (EQA) scheme. Methods We collected 122 heparinized plasma samples of patients admitted to the emergency department with thoracic pain or supraventricular tachyarrhythmia. Moreover, we also analyzed 20 control samples distributed in an EQA and 26 plasma pools prepared from healthy subjects and patients with myocardial infarction. We evaluated 4 different methods for cTnI assay: STAT Architect High Sensitive TnI (Abbott Diagnostics), ADVIA Centaur Troponin I Ultra (Siemens Healthcare Diagnostics), ST AIA-Pack cTnI Third Generation (Tosoh Bioscience), and Access AccuTnI + 3 (Beckman Coulter Diagnostics). Results Systematic differences between cTnI methods were observed. However, correlation coefficients (R from 0.976 to 0.990) between the log-transformed cTnI values measured in all 168 samples were significantly better (p = 0.0037) than those obtained considering only the 122 patients' samples. cTnI values measured in EQA and pool samples were included within the 95% prediction intervals of linear regressions calculated with those of patients' samples. After the recalibration of cTnI values based on the robust principal component analysis approach the between-methods variability decreased significantly (about 40% around the cut off values). Conclusions Our pilot study suggests that EQA schemes for cTnI immunoassay methods, based on both quality control samples with tested commutability and robust statistical analyses, are able to evaluate between-methods variability as well as allow a reliable recalibration and harmonization of results.

Background: The aim of this study is to test the hypothesis whether the combined use of a cardio-specific biomarker, the brain natriuretic peptide (BNP) and a marker of early renal damage, the assay of urinary neutrophil gelatinase-associated lipocalin (uNGAL), may improve risk stratification in pediatric cardiac surgery. Methods: We prospectively enrolled 135 children [median age 7 (interquartile range 1–49) months] undergoing to cardiac surgery for congenital heart disease. All biomarkers were evaluated pre- and post-operatively at different times after cardiopulmonary-bypass (CPB): uNGAL at 2, 6 and 12 h; BNP at 12 and 36 h; serum creatinine at 2, 6, 12, and 36 h. Primary endpoints were development of acute kidney injury (AKI) (defined as 1.5 serum creatinine increase) and intubation time. Results: AKI occurred in 39% of patients (65% neonates and 32% older children, p=0.004). The peak of uNGAL values occurred more frequently at 2 h. uNGAL values at 2 h [median 28.2 (interquartile range 7.0–124.6) ng/L] had a good diagnostic accuracy for early diagnosis of AKI with an AUC (area under the curve) ROC (receiver operating characteristic) curve of 0.85 (SE 0.034). Using multivariable logistic regression analysis, development of AKI was significantly associated with uNGAL values at 2 h after CPB [OR=1.88 (1.30–2.72, p=0.001)], together with the CPB time and Aristotle score, as an index of complexity of the surgical procedure, while pre-operative BNP values were not. Furthermore, uNGAL and pre-operative BNP values (together with Aristotle score) were significantly associated with adverse outcome (longer intubation time and mortality). Conclusions: Pre-operative BNP and uNGAL values after surgery (together with the Aristotle score) were independently associated with a more severe course and worse outcome in children undergoing cardiac surgery for congenital heart disease.

The aim of this study is to better characterize the time courses of BNP levels throughout the first days of life in larger populations of neonate and infant with or without congenital heart diseases (CHD) in order to increase the diagnostic accuracy of BNP assay in pediatric patients with CHD.BNP was measured by an automated platform (Triage BNP reagents, ACCESS Immunoassay Systems, Beckman Coulter, Inc., Fullerton, CA 92835) in 218 neonates and infants with different CHD; 222 healthy children, matched for age, served as controls.BNP values were significantly higher (P0.001) in the whole group of CHD patients (median 1029.8 ng/L, range 25-20,152 ng/L) than in controls (median 149.5 ng/L, range 9-866 ng/L). A different trend between BNP values and age was observed in healthy subjects and CHD patients. After an initial increase within the first 4 days of life, BNP values in CHD patients tend to stabilize to high values in the following days. On the contrary, in control subjects a peak of BNP levels was observed in the second or third day, followed by a progressive decrease. Therefore, the diagnostic accuracy of BNP assay, calculated in the samples collected in the first four days of life (AUC of ROC analysis 0.86, 95% CI 0.83-0.90) was significantly lower (P0.0001) compared to samples collected from 5 days to 30 days of life (AUC 0.97, 95% CI 0.95-0.99). Optimal cut-off values for BNP assay, as calculated by ROC analysis, were also age-dependent (cutoff for the first 4 days of life: 363.5 ng/L; cutoff values from 5 to 30 days of life: 109.5 ng/L).Our study demonstrates that differences in time-courses of BNP values between newborns with and without CHD throughout the first days of life clearly affect the diagnostic accuracy of BNP assay. Indeed, the diagnostic accuracy of BNP assay in discriminating between healthy newborns and CHD patients progressively increases after the 4th day of life. As a result, also cutoff values of BNP assay greatly change throughout the first days of life. However, decision values of BNP assay are strongly method-dependent, consequently clinicians should give great care to compare results obtained by different laboratories, especially when different methods are used.

Background: The goal of the present study was to evaluate the diagnostic accuracy of B-type natriuretic hormone (BNP) assay in children with congenital heart disease (CHD) in the first month of life. Methods: BNP was measured in 152 neonates with CHD; 154 healthy children matched for age were used as controls. BNP was measured with a fully automated platform (Triage BNP reagents, Access Immunoassay Systems, Beckman Coulter, Inc., Fullerton, CA, USA). Results: BNP values were significantly higher (p Conclusions: BNP may be considered a useful marker for screening in the integrated approach of newborns, infants and children with suspected CHD. However, the accuracy of the BNP assay varies greatly during the first month of extra-uterine life, showing the lowest diagnostic accuracy in the first 3 days after birth. After the second week of life, the biomarker becomes more accurate in ruling in CHD. Clin Chem Lab Med 2010;48:1333–8.

Background: In order to assess the reference intervals for B-type natriuretic hormone (BNP) in the first days of life, we measured peptide concentrations using the fully automated Access platform. Methods: Plasma BNP was measured in 188 apparently healthy newborns and infants throughout the first month of extra-uterine life, as well as in 245 healthy infants ranging from 1 month to 12 years of age. Results: BNP showed the highest concentrations in the first 2 days of life, with a progressive decline afterwards. Moreover, BNP values in the first week of life were significantly higher (p Conclusions: According to this data, our study indicates that at least two reference intervals should be used for newborns and infants. The first, with higher BNP values for neonates in the first week of extra-uterine life, and the other, with lower BNP values for infants aged 2 weeks to 12 years. Clin Chem Lab Med 2010;48:697–700.

BACKGROUND The clinical usefulness of B-type natriuretic peptide (BNP) assay in congenital heart diseases is still controversial. We evaluated the diagnostic accuracy and clinical relevance of this assay in different cardiovascular hemodynamic conditions in pediatric patients with congenital heart diseases. MATERIALS AND METHODS BNP was measured in 173 healthy individuals and in 382 pediatric patients with congenital heart diseases. We identified five subgroups of hemodynamic conditions: left ventricular volume overload, right ventricular volume overload, left ventricular pressure overload, right ventricular pressure overload, and biventricular volume overload. RESULTS BNP was higher (P

The routine use of brain natriuretic peptide (BNP) in pediatric cardiac surgery remains controversial. Our aim was to test whether BNP adds information to predict risk in pediatric cardiac surgery.In all, 587 children undergoing cardiac surgery (median age 6.3 months; 1.2–35.9 months) were prospectively enrolled at a single institution. BNP was measured pre-operatively, on every post-operative day in the intensive care unit, and before discharge. The primary outcome was major complications and length ventilator stay >15 days. A first risk prediction model was fitted using Cox proportional hazards model with age, body surface area and Aristotle score as continuous predictors. A second model was built adding cardiopulmonary bypass time and arterial lactate at the end of operation to the first model. Then, peak post-operative log-BNP was added to both models. Analysis to test discrimination, calibration, and reclassification were performed.BNP increased after surgery (pOur data indicates that BNP may improve the risk prediction in pediatric cardiac surgery, supporting its routine use in this setting.

The study aims are to evaluate the analytical performance and the clinical results of the chemiluminescent Access AccuTnI+3 immunoassay for the determination of cardiac troponin I (cTnI) with DxI 800 and Access2 platforms and to compare the clinical results obtained with this method with those of three cTnI immunoassays, recently introduced in the European market. The limits of blank (LoB), detection (LoD), and quantitation (LoQ) at 20% CV and 10% CV were 4.5 ng/L and 10.9 ng/L, 17.1 and 30.4 ng/L, respectively. The results of STAT Architect high Sensitive TnI (Abbott Diagnostics), ADVIA Centaur Troponin I Ultra (Siemens Healthcare Diagnostics), ST AIA-Pack cTnI third generation (Tosoh Bioscience), and Access AccuTnI+3 (Beckman Coulter Diagnostics) showed very close correlations (R ranging from 0.901 to 0.994) in 122 samples of patients admitted to the emergency department. However, on average there was a difference up to 2.4-fold between the method measuring the highest (ADVIA method) and lowest cTnI values (AccuTnI+3 method). The consensus mean values between methods ranged from 6.2% to 29.6% in 18 quality control samples distributed in an external quality control study (cTnI concentrations ranging from 29.3 ng/L to 1557.5 ng/L). In conclusion, the results of our analytical evaluation concerning the AccuTnI+3 method, using the DxI platform, are well in agreement with those suggested by the manufacturer as well as those reported by some recent studies using the Access2 platform. Our results confirm that the AccuTnI+3 method for the Access2 and DxI 800 platforms is a clinically usable method for cTnI measurement.

Retrograde cardioplegia (RC) delivery may result in suboptimal myocardial protection, due to leakage of cardioplegia to the right atrium. This study was undertaken to assess the efficacy of a double balloon cannula (DBC) occluding the coronary sinus ostium during RC. Fifteen patients were randomly assigned to receive RC via a conventional cannula or via the DBC. Cardioplegia was started at 200 ml/min, and the flow rate (Q) was adjusted to obtain a perfusion pressure (P) of 25-40 mmHg. Blood samples were collected at 13 different time points. The CPK-MB and TnI levels were measured on each sample. The use of the DBC was associated with increased P (P=0.03) at a lower Q (P=0.02). The CK-MB levels were significantly increased in both groups (P

Objective: It has been suggested that cardiac surgery-related ischemia-reperfusion injury to the myocardium is caused by the oxidative stress, derived from the formation of reactive oxygen species in the early phases of the reperfusion. The availability of cysteine, mostly deriving from homocysteine (Hcy) via the trans-sulfuration pathway, is determinant for the synthesis of glutathione (GSH), which in turn acts as a first line of defence against oxidative stress. Indeed, an increased consumption of Hcy in response to oxidative stress has been described. Previous research has shown that Hcy levels increase during the first weeks or months after coronary artery bypass grafting (CABG). This study was designed to evaluate the Hcy metabolism in CABG patients during the early postoperative period. Methods: Serum Hcy and folate were measured by an automatic immunometric system on blood samples obtained from 48 (mean age 67 ^ 10 years) consecutive patients undergoing CABG, preoperatively and at 0, 12, 48, and 120 h after surgery. A subgroup of 22 of these patients was also studied 6 months postoperatively. Results: A significant decrement of Hcy and folate was observed throughout the study ðP , 0:0001Þ from 17.3 ^ 9.3 to 8.5 ^ 5.6 mmol/l at 12 h postoperatively for Hcy, and from 5.1 ^ 2.8 to 2.5 ^ 1.5 ng/ml at 48 h for folate. The reduction of Hcy and folate levels remained significant after correction for haemodilution (as assessed by measurement of plasma proteins). Furthermore, the use of cardiopulmonary bypass significantly interacted with the time of sampling in affecting the Hcy levels. Hcy levels returned to near-baseline values 48 h postoperatively, and were similar to base-line at follow-up. Conclusion: Our study indicates that serum Hcy and folate levels are markedly reduced during the early postoperative period after CABG. This reduction is at least in part independent of haemodilution, and may be caused by an altered Hcy turnover, due to an increased consumption of GSH during and soon after CABG. q 2004 Elsevier B.V. All rights reserved.

ObjectivesWe investigated the main biomolecular features in the evolution of aortic stenosis, focusing on advanced lesions.Background“Degenerative” aortic valve stenosis shares risk factors and inflammatory similarities with atherosclerosis.MethodsWe compared nonrheumatic stenotic aortic valves from 26 patients undergoing surgical valve replacement (group A) and 14 surgical control patients (group B). We performed semiquantitative histological and immunohistochemical analyses on valve leaflets to measure inflammation, sclerosis, calcium, neoangiogenesis, and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression. We assessed heat shock protein 60 (hsp60) gene expression as an index of cellular stress and C-reactive protein, erythrocyte sedimentation rate, and fibrinogen as systemic inflammatory markers.ResultsIn group A valves, we found a prevalence of calcium nodules surrounded by activated inflammatory infiltrates, neovessels, and abundant ICAM-1, VCAM-1, and hsp60gene expression. Specimens from group B were negative for all of these markers, except 2 of 14 positivity for hsp60.The presence of active inflammatory infiltrates correlated with an abundance of thin neovessels (p < 0.01) and hsp60gene expression (p = 0.01), whereas neoangiogenesis correlated with inflammation (p = 0.04), calcium (p = 0.01), and hsp60gene expression (p = 0.04).Conclusions“Degenerative” aortic valve stenosis appears to be a chronic inflammatory process associated with atherosclerotic risk factors. The coexistence of neoangiogenesis, T-lymphocyte infiltration, adhesion molecules, and hsp60gene expression indicates an active immunomediated process in the final phases of the disease.

Over the last 5 years, several immunoassay methods for the measurement of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) became commercially available. Recent studies have confirmed the clinical usefulness of measurements of these cardiac natriuretic peptides for the prognostic stratification of patients with congestive heart failure, for the detection of left ventricular systolic and/or diastolic dysfunction, and for the differential diagnosis of dyspnea (1)(2)(3)(4). However, to answer the most urgent requests of current clinical practice and to allow widespread use of BNP and NT-proBNP assays, some key issues had to be solved, such as increasing the sensitivity, precision, and experimental practicability (5). The aim of the present study was to evaluate and compare the analytical and clinical performance of five commercial natriuretic peptide immunoassays. Throughout this report, the values in healthy individuals and patients are reported as the range, median, and 25th and 75th percentiles. We enrolled 172 healthy adults (89 women and 83 men; age range, 16–73 years; median age, 49.0 years; 25th percentile, 38 years; 75th percentile, 58 years). All participants were nonobese (body mass index, 19.4–27.6 kg/m2, 24 kg/m2, 22.8 kg/m2, and 25.6 kg/m2), normotensive (diastolic blood pressure, 60–85 mmHg, 70 mmHg, 70 mmHg, and 80 mmHg; systolic blood pressure, 90–140 mmHg, 120 mmHg, 102.5 mmHg, and 124.5 mmHg), and free from acute or chronic diseases. All participants had main plasma indices (including creatinine, urea nitrogen, glucose, uric acid, albumin, enzymes, electrolytes, and hemoglobin) within the appropriate reference intervals, and normal erythrocyte and leukocyte counts …

OBJECTIVE: The aim of this study was to evaluate the diagnostic and prognostic accuracy of brain natriuretic peptide assay in neonates and children undergoing surgery for congenital heart disease. DESIGN: Prospective, observational study. SETTING: Single center. PATIENTS: We enrolled 336 consecutive children (median age, 6 mo [range, 0-37 mo]) undergoing cardiac surgery (87 neonates; age, 7 d [5-12]; median, 25th-75th percentile; 24 infants and children; age, 11 mo [4-60]) and 436 healthy controls. INTERVENTIONS: Brain natriuretic peptide was measured preoperatively, on every postoperative day in the ICU, and at discharge. Intubation time was the primary outcome. MEASUREMENTS AND MAIN RESULTS: Preoperative brain natriuretic peptide values in patients with congenital heart disease were higher than those in controls (p < 0.01). Brain natriuretic peptide had a good diagnostic accuracy in discriminating between patients with congenital heart disease and healthy controls with an area under the curve = 0.918 for neonates and area under the curve = 0.894 for older children. The best cutoff values, calculated by receiver operating characteristic analysis, were different for the two age subgroups with cutoff values of 363.5 ng/L for neonates and 23.5 ng/L for older children. At 24 hours after surgery, although brain natriuretic peptide decreased in neonates (baseline 2723 vs 1290 ng/L, p < 0.001), it increased in children (60 vs 365 ng/L at 24 hours, p < 0.001). Multivariable analysis identified the preoperative level of brain natriuretic peptide in infant/children and the difference in brain natriuretic peptide value (baseline 24 hours) in neonates, as independent predictors of intubation time. Furthermore, body surface area, Aristotle score, and cardiopulmonary bypass time had an independent significant effect on the endpoint in either group. CONCLUSIONS: Baseline cardiac endocrine function and its response to surgical stress are dependent on age in neonates and children, undergoing cardiac surgery for congenital heart disease. Brain natriuretic peptide shows a good diagnostic and prognostic accuracy in this setting, with different features in either neonates or infants/children subsets.

Background: Neutrophil gelatinase-associated lipocalin (NGAL) has been suggested as the most promising biomarker of acute kidney injury. However, there are no reliable data on analytical sensitivity and reference limits of urinary NGAL (uNGAL) assay in pediatric age. The aim of the present study is to evaluate the analytical sensitivity and the reference range of uNGAL measured in urine specimens of pediatric age with the fully automated platform ARCHITECT (R) i1000. Methods: A total of 333 urine samples were collected from 25 healthy newborns (16 males and 9 females; age 1-4 days) and 308 children (150 males and 147 females; mean age 80.7 months, range 0.63-248 months) and assayed for uNGAL by two different Italian centers (Department of Laboratory Medicine of the Fondazione Toscana G. Monasterio of Pisa and Massa and the Clinical Pathology Laboratory Unit of Istituto Giannina Gaslini of Genova). Results: The calculated limits of blank (LOB) and detection (LOD) values were 0.5 ng/mL and 0.95 ng/mL, respectively. The distribution of uNGAL values approximated a log-normal distribution (median 5.2 ng/mL, interquartile range 2.5-12.8 ng/mL, 99th percentile 117.6 ng/mL). uNGAL values of the 25 neonates were significantly higher than those of 308 children (neonates: mean 44.2 ng/mL, median 30.3 ng/mL, range 5.2-137.4 ng/mL; children: mean 10.2 ng/mL, median 4.6 ng/mL, range 0.2-146.7 ng/mL; p

The high prevalence of obesity in children may increase the magnitude of lifetime risk of cardiovascular disease (CD). At present, explicit data for recommending biomarkers as routine pre-clinical markers of CD in children are lacking. C-type natriuretic peptide (CNP) is assuming increasing importance in CD; in adults with heart failure, its plasma levels are related to clinical and functional disease severity. We have previously reported five different reference intervals for blood CNP as a function of age in healthy children; however, data on plasma CNP levels in obese children are still lacking. Aim of this study was to assess CNP levels in obese adolescents and verify whether they differ from healthy subjects. Plasma CNP was measured in 29 obese adolescents (age: 11.8 ± 0.4 years; BMI: 29.8 ± 0.82) by radioimmunoassay and compared with the reference values of healthy subjects. BNP was also measured. Both plasma CNP and BNP levels were significantly lower in the obese adolescents compared to the appropriate reference values (CNP: 3.4 ± 0.2 vs 13.6 ± 2.3 pg/ml, p

Background: Interest in hormonal response after pediatric cardiac surgery is growing, but many aspects remain unclear. The aim of this study was to test age-related variations and prognostic values of thyroid hormones, and brain natriuretic peptide (BNP) levels before and after surgery. Methods and Results: A total of 162 children undergoing cardiac surgery were divided into 3 age groups (group 1, n=57 neonates; group 2, n=58 infants; group 3, n=47 toddlers). Free thyroid hormones (fT3 and fT4), thyrotropin (thyroid-stimulating hormone [TSH]) and BNP were measured preoperatively, daily postoperatively in the intensive care unit and after 15 days. The primary outcome was time to extubation (TTE; variable used as time to event by survival analysis). The hormonal response differed among age groups. In older children the TSH nadir occurred at 6–12 h after surgery (0.42 mIU/L, P

C-type natriuretic peptide (CNP) is assuming increasing importance in cardiovascular disease, and in adults its plasma levels are related to clinical and functional disease severity. Data are scarce regarding the reference values for CNP in infancy. Aim of this study was to assess the reference intervals for CNP in human healthy newborns and infants. Plasma CNP was measured in 121 healthy children divided into: 41 newborns (age 0-3 days), 24 newborns (4-30 days), 22 infants (1-12 months) and 32 children (1-12 years). A group of 32 healthy adult subjects (age 64 ± 1 years) was also studied. CNP was measured by a specific radioimmunoassay. Between- and within-assay variability resulted ≤ 30 and 20%, respectively and analytical sensitivity 0.77 ± 0.05 pg/tube. Plasma CNP resulted significantly higher in children than in adult subjects (13.6 ± 1.2 pg/ml vs. 7.4 ± 1.0 pg/ml, p=0.030). When the results were analyzed as a function of the age the reference intervals for plasma CNP resulted: 11.6 ± 2.1 pg/ml for newborns (0-3 days), 16.4 ± 3.7 pg/ml for newborns (4-30 days), 15.4 ± 2.7 pg/ml for infants (1-12 months), 13.6 ± 2.3 pg/ml for children (1-12 years) [p=0.01 newborns (4-30 days) vs. adults; p=0.03 infants (1-12 months) vs. adults]. CNP showed the highest concentrations after 12h of life with a peak between 4 and 5 days of life and with a progressive decline afterwards. According to these data at least five different reference intervals for CNP determinations should be used. These observations may be helpful for future clinical application of CNP in human children.

Background We evaluated the analytical characteristics of electrochemiluminescence (ECLIA) immunoassay for NT-proBNP (proBNP II, Roche Diagnostics, Germany) and compared its analytical performance to that of the previous polyclonal method. Methods We measured NT-proBNP in EDTA plasma samples of 177 consecutive cardiac patients (69 females and 108 males; mean age 62.2 ± 16.4 years, range 13 to 96 years) with monoclonal and polyclonal ECLIA methods following manufacturer's instructions using an Elecsys® 2010 analyzer. Results Monoclonal ECLIA method for NT-proBNP assay showed an imprecision (CV%) lower than 3% at the cut-off value (i.e., 150 ng/L). No significant interference was found in plasma samples containing high levels of hemoglobin, triglycerides or bilirubin. EDTA plasma showed slightly, but significantly lower NT-proBNP values than serum (on average − 6.3%) and lithium-heparinized plasma (on average − 3.9%) samples. Finally, a very close linear regression was found between the NT-proBNP values found by either monoclonal or polyclonal ECLIA method (monoclonal ECLIA = − 72.17 + 1.04 polyclonal ECLIA, n = 177, R = 0.993). Conclusions The monoclonal ECLIA method showed very similar analytical characteristics with slightly lower NT-proBNP results (on average − 2.5%) than the polyclonal ECLIA method. The difference between monoclonal and polyclonal methods seems to be too slight to change the reference range and decisional values for NT-proBNP assay, as previously assessed by the polyclonal ECLIA method.

Summary Objective We evaluated and compared the analytical and clinical performance of the TnI-Ultra immunoassay for cardiac Troponin I (cTnI) measurement, carried out on the fully automated ADVIA Centaur and ADVIA Centaur CP ® platforms (Siemens Medical Solutions Diagnostics SrL), and that of Access AccuTnI™, carried out on the UniCell ® DxI 800 platform (Beckman Coulter, Inc., Fullerton). Methods We assayed 645 plasma Li-heparin samples of healthy subjects and 230 of patients with cardiovascular diseases (70 with a cTnI value higher than the decision level for acute myocardial infarction) by TnI-Ultra and Access AccuTnI™ immunoassays. Results The total imprecision (CV) profile of TnI-Ultra method was determined by repeatedly measuring 19 plasma pools, with different concentrations of TnI, in 20 different runs using two reagent lots; the CV ranged from 25% (at 0.02 μg/L) to less than 5% (for levels greater than 0.4 μg/L). On average, functional sensitivity (i.e. concentration measured with an imprecision of 10% CV) of TnI-Ultra method was 0.057 μg/L. The 99th percentile of normal distribution, calculated by enrolling a control group of 645 healthy subjects (278 males and 367 females; mean age of 47.4 ± 16.2 years, range 15–89 years), was 0.072 μg/L. Therefore, the ratio between functional sensitivity and 99th percentile values was less than 1 (i.e., 0.057/0.072 = 0.79), while for Access AccuTnI™ resulted 0.07/0.06 = 1.16. A close linear regression was found between the cTnI values obtained with the two methods only when the samples of patients with cardiac disease were taken into account (TnI-Ultra = −0.192 + 1.434 AccuTnI T ; R = 0.976; n = 230). A significant bias was found between the two methods by means of Bland-Altman plot (mean difference 38.9%), but when 368 healthy subjects were considered, no significant linear regression was found between these two methods ( R = 0.002, p = 0.9624). Conclusion Our results indicate that the TnI-Ultra immunoassay carried out on the fully automated ADVIA Centaur platforms shows analytical characteristics well in agreement with the quality specifications recommended for cardiac troponin assay.

BACKGROUND In response to many stress stimuli, cardiomyocytes produce a common set of heat shock proteins (HSP). Up-regulation of HSP70-1 (the inducible isoform) is known to reduce the risk of myocardial cell damage during open-heart surgery and seems to be protective against ischemia. We assessed hsp70-1 gene expression during blood cardioplegic arrest in children undergoing surgical correction of congenital heart defects. METHODS In tissue samples taken from the right atrium of 59 pediatric patients, we examined hsp70-1 gene expression using a real-time quantitative reverse transcription PCR, with 18S rRNA as internal standard. RESULTS On average, hsp70-1 gene expression was higher than the baseline level by a factor of 1.44+/- 0.17 (mean+/-SEM). A significant relationship between hsp70-1 mRNA levels and aortic cross-clamp time was observed (R(2)=0.069, p=0.044). Conversely, no significant correlation was observed between hsp70-1 mRNA levels and temperature. CONCLUSIONS These data suggest that blood cardioplegia can induce an increment in the expression of hsp70-1, confirming its protective role in ischemia/reperfusion injury.

In animal models of conotruncal heart defects, an abnormal calcium sensitivity of the contractile apparatus and a depressed L-type calcium current have been described. Sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA) is a membrane protein that catalyzes the ATP-dependent transport of Ca(2+) from the cytosol to the SR. The activity of SERCA is inhibited by phospholamban (PLN) and sarcolipin (SLN), and all these proteins participate in maintaining the normal intracellular calcium handling. Ryanodine receptors (RyRs) are the major SR calcium-release channels required for excitation-contraction coupling in skeletal and cardiac muscle. Our objective was to evaluate SERCA2a (i.e., the SERCA cardiac isoform), PLN, SLN, and RyR2 (i.e., the RyR isoform enriched in the heart) gene expression in myocardial tissue of patients affected by tetralogy of Fallot (TOF), a conotruncal heart defect. The gene expression of target genes was assessed semiquantitatively by RT-PCR using the calsequestrin (CASQ, a housekeeping gene) RNA as internal standard in the atrial myocardium of 23 pediatric patients undergoing surgical correction of TOF, in 10 age-matched patients with ventricular septal defect (VSD) and in 13 age-matched children with atrial septal defect (ASD). We observed a significantly lower expression of PLN and SLN in TOF patients, while there was no difference between the expression of SERCA2a and RyR2 in TOF and VSD. These data suggest a complex mechanism aimed to enhance the intracellular Ca(2+) reserve in children affected by tetralogy of Fallot.

BACKGROUND The determination of cardiac troponins is routinely used for rule in/out, risk stratification, and follow-up of patients with acute coronary artery syndrome. We evaluated the analytical and clinical performance of the advanced immunoassay for troponin I (cTnI) carried out on an AxSYM platform (Abbott Diagnostic Division) and compared these characteristics to those of the previous version of this assay and to cTnI on the Access 2 immunoassay system (Beckman Coulter, Inc.). METHODS We assayed plasma samples from healthy subjects (n=66) and cardiac patients (n=132) using AxSYM Plus system assays called the old (OLD AxSYM) and advanced TnI (ADV AxSYM) methods and using an Access system. RESULTS An improvement in analytical sensitivity (detection limit) was observed for the advanced cTnI AxSYM compared to the previous method (0.014 vs. 0.31 microg/L), while the cTnI value for the 10% CV (i.e., functional sensitivity) was 0.41 microg/L for the ADV and 1.9 microg/L for the OLD method. The kinetics of cTnI release was similar, as evaluated in 25 patients with typical acute myocardial infarction (AMI). A close linear relationship was found between the two methods on the AxSYM system (OLD cTnI=7.436+6.858 ADV cTnI; R=0.968, n=214) and with the Access system (OLD AxSYM=7.154+7.9 Access, R=0.876, n=158; ADV AxSYM=0.23+1.209 Access, R=0.927, n=160). However, wide bias was found between the OLD and ADV AxSYM methods (mean difference 118.4 microg/L, p

Many complex cardiac defects produce a functionally single ventricle, in which there is mixing of the systemic and pulmonary circulations. The output from the functionally single ventricle is divided between the two circulations: the proportion going to the systemic and pulmonary vascular beds being determined by the relative resistance to flows within the respective circulations.

The clinical relevance of B-type natriuretic peptide (BNP) as a diagnostic tool and prognostic marker in patients with cardiovascular diseases has been confirmed recently (1)(2)(3). Over the last 5 years, several immunoassay methods for the measurement of BNP, which share some analytical characteristics, such as full automation, turnaround time 50%). Blood was collected between 0800 and 0900 after the individuals had fasted overnight and had rested for 20 min in a supine position. Immediately after withdrawal, blood samples (8–10 mL) were placed in ice-chilled disposable polypropylene tubes containing EDTA (1 mg/mL of plasma). Plasma samples were obtained shortly after venipuncture by centrifugation for 15 min at 4 °C and then were …

The non-thyroidal illness syndrome (NTIS) is considered a transient and completely reversible phenomenon, but it has been shown that it may last for several days postoperatively after coronary artery bypass grafting (CABG) surgery. This study was undertaken to assess thyroid function 6 months after uncomplicated CABG. The thyroid profile was evaluated in 40 consecutive patients undergoing CABG preoperatively, at 0, 12, 48, and 120 h postoperatively, and at 6-month follow-up. Triiodothyronine (T3), free T3 (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were assayed using a microparticle enzyme immunoassay. T4 and total serum thyroid hormone-binding capacity (T-uptake) were measured on the same samples using a fluorescence polarization immunoassay. Patients with severe systemic illness and patients treated with amiodarone were excluded. All patients were euthyroid at admission. Mean age was 67.4+/-9.0 years. There were 31 (77.5%) men. Typical NTIS was observed in all patients, and the FT3 concentration was still reduced by postoperative day 5 (p