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BackgroundSubstance use increases risk of cardiovascular events, particularly among women with additional risk factors like housing instability. While multiple substance use is common among unstably housed individuals, relationships between multiple substance use and cardiovascular risk factors like blood pressure are not well characterized.MethodsWe conducted a cohort study between 2016 and 2019 to examine associations between multiple substance use and blood pressure in women experiencing homelessness and unstable housing. Participants completed six monthly visits including vital sign assessment, interview, and blood draw to assess toxicology-confirmed substance use (e.g., cocaine, alcohol, opioids) and cardiovascular health. We used linear mixed models to evaluate the outcomes of systolic and diastolic blood pressure (SBP; DBP).ResultsMean age was 51.6years; 74% were women of color. Prevalence of any substance use was 85%; 63% of participants used at least two substances at baseline. Adjusting for race, body mass index and cholesterol, cocaine was the only substance significantly associated with SBP (4.71mmHg higher; 95% CI 1.68, 7.74) and DBP (2.83mmHg higher; 95% CI 0.72, 4.94). Further analysis found no differences in SBP or DBP between those with concurrent use of other stimulants, depressants, or both with cocaine, compared to those who used cocaine only.ConclusionsCocaine was the only substance associated with higher SBP and DBP, even after accounting for simultaneous use of other substances. Along with interventions to address cocaine use, stimulant use screening during cardiovascular risk assessment and intensive blood pressure management may improve cardiovascular outcomes among women experiencing housing instability.

Background Daratumumab (DARA) is a fully human anti-CD38 IgG1-κ monoclonal antibody drug used in the treatment of multiple myeloma (MM). While serum protein electrophoresis (SPEP) is an important assay for diagnosis and monitoring of patients with MM, DARA can appear in the γ-region as a single band and interfere with the interpretation of SPEP results. An approach to detect the interference is measuring the quantity of DARA in serum samples and assessing its impact on SPEP results. Immunoassays based on label-free technologies, i.e. label-free immunoassays (LFIA’s), can achieve real-time immunometric measurement without attaching a reporter molecule (enzyme, fluorophore, etc.) to the immunocomplex. The recorded time course of the immunocomplex formation allows for quantitation on initial binding rate, which facilitates rapid measurement within a few minutes. Based on the thin-film interferometry (TFI) technology, a rapid LFIA was established for the quantitation of DARA in serum samples. Methods The TFI-based LFIA for DARA was validated for imprecision (CV), accuracy, limit of quantitation (LOQ), and analytical measurement range (AMR). Interference to the LFIA was evaluated using a group of protein samples, as well as hemolytic, lipemic, and icteric clinical samples. Results The precision of the TFI-based LFIA’s for DARA ranged from 6.5% to 10.7% (within-run CV), and 7.4% to 11.6% (between-run CV), with a bias of −2.1% to 10.1%. The LOQ was 10 μg/ml (n = 4, CV 9.8%), with an AMR ranging from the LOQ to 1000 μg/ml. The LFIA was used to measure 37 patient samples submitted for SPEP testing. The LFIA results were 100% consistent with the history of DARA use as documented in the medical record. Conclusions The TFI-based LFIA was successful at accurately identifying DARA in serum samples and can be used to identify DARA interference in SPEP testing. This work demonstrates the applicability of label-free technologies, particularly the TFI technology, to clinical diagnostic needs. Given the simplicity and the speed of the testing process, the TFI technology provides a unique testing approach for the measurement of proteins in clinical samples.

Cardiac troponins T and I are proteins released into serum after cardiac injury, and are the standard biomarkers for patients presenting to the emergency department with a suspicion of acute myocardial infarction (AMI). Cardiac troponin that appears in blood within a few hours is due to release from the cytosolic pool. A sustained irreversible release over the ensuing days is due to the degradation of the myofibrils, although recent data have challenged this concept. The analytical sensitivity for troponin assays have significantly improved since the initial release of commercial troponin assays over 20 years ago. As a result, the specificity of troponin for AMI has steadily declined, with abnormal concentrations seen in many non-cardiac diseases such as renal failure, sepsis, pulmonary embolism, and cardiac injury after chemotherapy such as with trastuzumab and doxorubicin. There are many theories as to how troponin is released into blood from patients with reversible myocardial ischemia and from patients with cardiac damage that is not related to ischemia. These theories include release of free subunit release through bleb formation, transient imbalance of oxygen supply and demand such as what occurs with acute vasospasm of coronary vessels, pulmonary embolism with right heart damage, apoptosis, acute cardiac stress leading to release of catecholamines and integrins, myocardial stretching, inflammation, and release of degraded troponin peptides. The mechanisms for these etiologies are reviewed. Keywords: Troponin, Demand ischemia, Blebs, Integrins, Catecholamines, Stress, Chemotherapy, Heart failure, Apoptosis

Statin drugs are leading medication prescribed for treatment of dyslipidemic patients aimed at preventing both primary and secondary incidences of atherosclerosis-related cardiovascular events. Statin drugs competitively inhibit HMG-CoA reductase enzyme activity, thereby inhibiting cell-mediated cholesterol synthesis and reducing the low-density lipoprotein (LDL) cholesterol concentration of plasma. Conversely, the mechanism by which statins increase high-density lipoprotein (HDL) cholesterol concentration of plasma is not well understood. The plaque array method was used to examine the effect of statins on in vitro cholesterol particle formation. We observed that statins induced high-density cholesterol particle formation in buffer solution with or without the addition of human serum. Besides, simvastatin and lovastatin in their inactive pro-drug forms modulate formation of LDL and HDL cholesterol particles, indicating a novel nonenzymatic mechanism of statins. In a pilot study, screening of serum samples in the assay showed variation among patient samples in response to different statins. Specifically, screening of 50 serum samples with high cholesterol and statin treatment, compared with standard LDL-based measurement of statin efficacy, showed a good correlation for simvastatin (88%) and atorvastatin (84%). Taken together, our data indicate that statins, in addition to inhibiting enzyme-mediated cholesterol synthesis, have the capability to nonenzymatically modulate formation of LDL and HDL cholesterol particles in vitro. Similar interactions occurring in serum may provide a means to alter cholesterol particle formation in vivo.

Background Sulfonylureas are antidiabetic agents widely prescribed for the treatment of type-II diabetes. Detection of the presence of sulfonylureas in cases of unexplained hypoglycemia rules out other underlying pathophysiological conditions. The goal of this study was to develop and validate a qualitative liquid chromatography tandem mass spectrometry (LC–MS/MS) assay for the rapid identification of sulfonylureas in serum. Methods An LC–MS/MS assay was developed using an Agilent HPLC with an AB Sciex 3200 LC–MS/MS operating in ESI positive mode. Linearity, LOD, precision, matrix effect, recovery, carry-over and stability of the final method were evaluated for method validation. Concordance with another clinically validated LC–MS/MS method was evaluated using remnant samples from patients prescribed a sulfonylurea. Results The assay performed well with all validation data meeting pre-determined criteria. The method comparison study showed a correlation coefficient of 0.99 for glipizide, the most common sulfonylurea, despite both methods being validated as qualitative methods. To date the validated assay has been utilized in 19 cases of unexplained hypoglycemia presenting to the emergency department, in which 5 were sulfonylurea positive. Conclusion We have developed a rapid and sensitive LC–MS/MS sulfonylurea assay, and utilized this assay to assist in the differential diagnosis of unexplained hypoglycemia.

Background Macro-aspartate aminotransferase (macroAST) is a high molecular weight form of AST that is usually formed through association with immunoglobulin (Ig) in the circulation. As a result of reduced inactivation, clearance or excretion, AST values are persistently increased. This can lead to problems interpreting these values and diagnosing the patient, especially if clinicians are not aware of this phenomenon. Methods For a case of suspected macroAST, we compared three simple methods: polyethylene glycol precipitation, ultrafiltration, and Ig depletion using protein A and G. Results All three methods were consistent with a diagnosis of macroAST. Conclusions The protein A and G method was straightforward and provided unambiguous results. However, given the affinity of protein A and protein G, it likely only detects AST-IgG macrocomplexes.

Background Blood-based biomarkers such as cardiac troponin and B-natriuretic peptides are widely used in clinical practice for the diagnosis, rule out, and risk stratification for patients with acute coronary syndromes and heart failure. Because neither these nor any other laboratory test meets all clinical needs, there are many novel biomarkers that are proposed and evaluated each year for possible implementation into clinical practice. Results of clinical trials are used as a means to validate their effectiveness and to obtain regulatory approval. Methods and results Novel biomarkers are discovered through a targeted approach using knowledge of the pathophysiology disease process and an untargeted approach where proteins from tissues or blood of disease patients are compared against healthy subjects or those with benign conditions. Once a candidate biomarker has been identified, it is important to understand where the protein is located and how it is released into blood. In designing trials, the requirements for Food and Drug Administration clearance and approval should be taken into consideration. There are preanalytical studies that should be considered including the preservative used to collect samples and in vivo and in vitro analyte stability. If the analyte is not stable, a surrogate marker could be used such as stable "pro" molecules (precursor proteins) may be preferred. Assay imprecision and bias, biological variation and criteria for the establishment of a reference range are important analytical attributes. The need for harmonization and commutability and correlation of results to other markers and clinical outcomes are important postanalytical attributes of novel biomarkers. Conclusions Inadequate adherence to these variables when conducting clinical trials reduces the quality and value of the information contained in literature reports of novel serum/plasma-based biomarkers.

Increased total serum cholesterol and low-density lipoprotein cholesterol concentrations are associated with atherosclerosis and risk for myocardial infarction and stroke. Those who have high cholesterol with other factors that predispose them to cardiovascular disease should be treated with cholesterol-lowering medications. The pathophysiology of hyperlipidemia is important in the proper selection of drug therapy. Patients who have increased cholesterol synthesis should be medicated with drugs that reduce in vivo cholesterol production, whereas those who have increased dietary absorption of cholesterol should be treated with drugs that inhibit dietary absorption. Sterol-based biomarkers are available to assess the cause of hypercholesterolemia and may have an impact on therapeutic selection.

Background The analysis of blood for β-sitosterol and campesterol is the measures of cholesterol absorption while lathosterol is a measure of cholesterol synthesis. Methods The biological variability of β-sitosterol, campesterol, and lathosterol was measured using liquid-chromatography tandem mass spectrometry from a cohort of 25 apparently healthy subjects, where blood was taken once every weeks for 6 weeks. The analytical, intra-individual, and group inter-individual variations (CV A , CV I , and CV G , respectively) were calculated. Results Using absolute values, the CV I for β-sitosterol, campesterol, and lathosterol was 11.8%, 11.8%, and 22.5%, respectively, and the CV G was 28.5%, 28.8%, and 52.0%, respectively. This produced reference change values of about 24–36% for declining values and 32–47% for increasing values. The index of individuality was between 0.41 and 0.58, indicating that population based reference values are of little use for these biomarkers. The number of points needed for a homeostatic setpoint was 5 samples for β-sitosterol and campesterol, and 19 samples for lathosterol. Similar findings were observed for values when normalized to total cholesterol. These results were higher than the biological variation for total, low density and high density cholesterol obtained from the literature. Results were essentially identical when sterol values were corrected to their respective total cholesterol concentration. Conclusions The establishment of the biological variation for these biomarkers enables their use in the interpretation of results from clinical trials and lipid lowering treatment of patients at risk for cardiovascular disease in clinical practice.

Clinical guidelines recommend laboratory monitoring of transgender persons on cross-sex hormone therapy, but gender-specific reference intervals leave clinicians with the dilemma of deciding what is "normal" for each patient. The goal of this study was to identify consistent changes in measurands with hormone therapy and determine which reference interval is appropriate.Laboratory data were abstracted from the medical records of 55 male-to-female patients on hormone therapy and compared with 20 male and 20 female nontransgender subjects.Hemoglobin, hematocrit, and low-density lipoprotein resembled female values (P.005), while alkaline phosphatase, potassium, and creatinine resembled male values (P.05). Triglycerides were higher (P.005) than either the male or female groups. The remainder of the measurands showed no differences.Use of correct reference intervals in interpreting laboratory results reduces the risk of testing-related diagnostic error. Preliminary data suggest that new reference intervals need to be established for transgender patients.

Background This is a case of a citalopram and olanzapine overdose causing seizures and severe cardiotoxicity. Case Report A 21-year-old man presented unresponsive, with seizures, to an Emergency Department. The patient’s initial electrocardiogram demonstrated a widened QRS of 160 ms and a normal QT/QTc interval of 400/487 ms consistent with cardiac sodium channel blockade. Within 30 min of arrival, peak citalopram and olanzapine levels were measured to be 522 ng/mL and 505 ng/mL, respectively. Measured levels remained supratherapeutic until 13.6 h and 42.6 h after arrival for citalopram and olanzapine, respectively. The patient developed bradycardia and hypotension that required multimodal therapies including sodium bicarbonate boluses, vasopressors, and transvenous pacing. Seizures and cardiotoxicity continued while citalopram, but not olanzapine, was supratherapeutic. Conclusions This case describes cardiotoxicity directly correlated with supratherapeutic citalopram levels in overdose.

Objectives The goal of this study was to demonstrate that copeptin levels Background Copeptin is secreted from the pituitary early in the course of AMI. Methods This was a 16-site study in 1,967 patients with chest pain presenting to an ED within 6 hours of pain onset. Baseline demographic characteristics and clinical data were collected prospectively. Copeptin levels and a contemporary sensitive cTnI (99th percentile 40 ng/l; 10% coefficient of variation 0.03 μg/l) were measured in a core laboratory. Patients were followed up for 180 days. The primary outcome was diagnosis of AMI. Final diagnoses were adjudicated by 2 independent cardiologists blinded to copeptin results. Results AMI was the final diagnosis in 156 patients (7.9%). A negative copeptin and cTnI at baseline ruled out AMI for 58% of patients, with a negative predictive value of 99.2% (95% confidence interval: 98.5 to 99.6). AMIs not detected by the initial cTnI alone were picked up with copeptin >14 pmol/l in 23 (72%) of 32 patients. Non–ST-segment elevation myocardial infarctions undetected by cTnI at 0 h were detected with copeptin >14 pmol/l in 10 (53%) of 19 patients. Projected average time-to-decision could be reduced by 43% (from 3.0 h to 1.8 h) by the early rule out of 58% of patients. Both abnormal copeptin and cTnI were predictors of death at 180 days (p Conclusions Adding copeptin to cTnI allowed safe rule out of AMI with a negative predictive value >99% in patients presenting with suspected acute coronary syndromes. This combination has the potential to rule out AMI in 58% of patients without serial blood draws. (Investigation of the Biomarker Copeptin in Patients With Acute Myocardial Infarction [ NCT00952744 ])

Objectives The purpose of this study was to assess the impact of atrial fibrillation (AF) on the performance of mid-region amino terminal pro-atrial natriuretic peptide (MR-proANP) in comparison with the B-type peptides (BNP and NT-proBNP) for diagnosis of acute heart failure (HF) in dyspneic patients. Background The effects of AF on the diagnostic and prognostic performance of MR-proANP in comparison with the B type natriuretic peptides have not been previously reported. Methods A total of 1,445 patients attending the emergency department with acute dyspnea had measurements taken of MR-proANP, BNP, and NT-proBNP values on enrollment to the BACH trial and were grouped according to presence or absence of AF and HF. Results AF was present in 242 patients. Plasma concentrations of all three peptides were lowest in those with neither AF nor HF and AF without HF was associated with markedly increased levels (p l 0.00001). HF with or without AF was associated with a significant further increment (p l 0.00001 for all three markers). Areas under receiver operator characteristic curves (AUCs) for discrimination of acute HF were similar and powerful for all peptides without AF (0.893 to 0.912; all p l 0.001) with substantial and similar reductions (0.701 to 0.757) in the presence of AF. All 3 peptides were independently prognostic but there was no interaction between any peptide and AF for prediction of all-cause mortality. Conclusions AF is associated with increased plasma natriuretic peptide (MR-proANP, BNP and NT-proBNP) levels in the absence of HF. The diagnostic performance of all three peptides is impaired by AF. This warrants consideration of adjusted peptide thresholds for diagnostic use in AF and mandates the continued search for markers free of confounding by AF.

Objectives We evaluated a third-generation high sensitivity “guidelines acceptable” troponin I assay (hs-cTnI) against a contemporary “clinically usable” troponin assay (cTnI). Design and methods Remnant samples of undifferentiated emergency department (ED) patients with suspected acute coronary syndrome were enrolled. Baseline and 90-minute samples were analyzed for cTnI and hs-cTnI. Sensitivity, specificity, positive and negative predictive values for AMI and 30-day adverse cardiac events (ACE) were compared. Results Of 486 ED patients, there were 465 patients who had blood remaining at the presentation for the hs-cTnI assays, with 12 AMIs. At presentation, the clinical sensitivity and specificity for AMI was 75% and 97% for cTnI and 83.3 and 82.1% for hs-cTnI. There were 407 patients who had paired baseline and 90-minute blood samples for cTnI and hs-cTnI including 9 of the 12 AMI patients. The sensitivity and specificity was 77.7% and 96.5% for cTnI and 100% and 81.9% for hs-cTnI at 90 min. A Δ change of 30% increase from baseline to 90 min improved the specificity to 94.5% (95% CI 92%–96%) without lowering the sensitivity. When AMI was defined as a Δ30% change of hs-cTnI at t = 0 and 90 min and one hs-cTnI result > 99th percentile cutoff, more than 3 times as many patients met the diagnostic criteria for AMI compared to results from the normal sensitive troponin assay; 28 (6.9%) for hs-cTnI vs. 9 (2.2%) with cTnI. There were 37 in-hospital or 30-day events, producing an OR of 3.03, 95% CI: 0.86–9.59 for cTnI, and 2.54, 95% CI: 1.27–5.10 for hs-cTnI, which detected 11 more cases. Conclusions The hs-cTnI assay achieved a 90-minute rule out for AMI and detected more 3 times as many AMI cases. The specificity increased with the Δ30% criteria. The hs-cTnI assay also detected more cases of patient at risk for adverse cardiac events at 30 days.

Objectives The aim of this study was to determine the prognostic utility of midregion proadrenomedullin (MR-proADM) in all patients, cardiac and noncardiac, presenting with acute shortness of breath. Background The recently published BACH (Biomarkers in Acute Heart Failure) study demonstrated that MR-proADM had superior accuracy for predicting 90-day mortality compared with B-type natriuretic peptide (area under the curve: 0.674 vs. 0.606, respectively, p Methods The BACH trial was a prospective, 15-center, international study of 1,641 patients presenting to the emergency department with dyspnea. Using this dataset, the prognostic accuracy of MR-proADM was evaluated in all patients enrolled for predicting 90-day mortality with respect to other biomarkers, the added value in addition to clinical variables, as well as the added value of additional measurements during hospital admission. Results Compared with B-type natriuretic peptide or troponin, MR-proADM was superior for predicting 90-day all-cause mortality in patients presenting with acute dyspnea (c index = 0.755, p 3.28), and it was also superior to all other biomarkers. MR-proADM added significantly to the best clinical model (bootstrap-corrected c index increase: 0.775 to 0.807; adjusted standardized hazard ratio: 2.59; 95% confidence interval: 1.91 to 3.50; p Conclusions MR-proADM identifies patients with high 90-day mortality and adds prognostic value to natriuretic peptides in patients presenting with acute shortness of breath. Serial measurement of this biomarker may also prove useful for monitoring, although further studies will be required. (Biomarkers in Acute Heart Failure [BACH]; NCT00537628 )

Pharmacogenetic testing is becoming more common; however, very few quality control and other reference materials that cover alleles commonly included in such assays are currently available. To address these needs, the Centers for Disease Control and Prevention's Genetic Testing Reference Material Coordination Program, in collaboration with members of the pharmacogenetic testing community and the Coriell Cell Repositories, have characterized a panel of 107 genomic DNA reference materials for five loci (CYP2D6, CYP2C19, CYP2C9, VKORC1, and UGT1A1) that are commonly included in pharmacogenetic testing panels and proficiency testing surveys. Genomic DNA from publicly available cell lines was sent to volunteer laboratories for genotyping. Each sample was tested in three to six laboratories using a variety of commercially available or laboratory-developed platforms. The results were consistent among laboratories, with differences in allele assignments largely related to the manufacturer's assay design and variable nomenclature, especially for CYP2D6. The alleles included in the assay platforms varied, but most were identified in the set of 107 DNA samples. Nine additional pharmacogenetic loci (CYP4F2, EPHX1, ABCB1, HLAB, KIF6, CYP3A4, CYP3A5, TPMT, and DPD) were also tested. These samples are publicly available from Coriell and will be useful for quality assurance, proficiency testing, test development, and research.

Background Galectin-3 is a carbohydrate binding protein that plays many important regulatory roles in inflammation, immunity and cancer. Recent studies indicate that galectin-3 is a mediator of heart failure development and progression. Development of an improved assay for galectin-3 measurement was necessary for appropriate clinical assessment. Key analytical performance characteristics, the reference distribution and association of galectin-3 levels with clinical outcome in heart failure patients are defined. Methods A two-site ELISA test was examined for measurement matrix, imprecision, limits of blank, detection, and quantitation, as well as linearity, high-dose hook effect, storage stability, cross-reactivity with nine similar compounds, interference with 22 common medications and icterus, lipemia and hemolysis, all in accordance with CLSI guidance. Also the effects of human anti-mouse antibodies and rheumatoid factor on recovery of galectin-3 were investigated. The reference interval was determined for 1092 ostensibly healthy individuals. The association of galectin-3 concentrations with an outcome of mortality was examined in a preliminary analysis of 129 acute decompensated heart failure patients. Results Galectin-3 results were equivalent when measured in serum or EDTA plasma. Imprecision studies demonstrated that the total CV was Conclusion This ELISA for galectin-3 measurement demonstrated acceptable analytical characteristics and was associated with mortality in a preliminary unadjusted analysis.

Objectives Our purpose was to assess the diagnostic utility of mid-regional pro–atrial natriuretic peptide (MR-proANP) for the diagnosis of acute heart failure (AHF) and the prognostic value of mid-regional pro-adrenomedullin (MR-proADM) in patients with AHF. Background There are some caveats and limitations to natriuretic peptide testing in the acute dyspneic patient. Methods The BACH (Biomarkers in Acute Heart Failure) trial was a prospective, 15-center, international study of 1,641 patients presenting to the emergency department with dyspnea. A noninferiority test of MR-proANP versus B-type natriuretic peptide (BNP) for diagnosis of AHF and a superiority test of MR-proADM versus BNP for 90-day survival were conducted. Other end points were exploratory. Results MR-proANP (≥120 pmol/l) proved noninferior to BNP (≥100 pg/ml) for the diagnosis of AHF (accuracy difference 0.9%). In tests of secondary diagnostic objectives, MR-proANP levels added to the utility of BNP levels in patients with intermediate BNP values and with obesity but not in renal insufficiency, the elderly, or patients with edema. Using cut-off values from receiver-operating characteristic analysis, the accuracy to predict 90-day survival of heart failure patients was 73% (95% confidence interval: 70% to 77%) for MR-proADM and 62% (95% confidence interval: 58% to 66%) for BNP (difference p Conclusions MR-proANP is as useful as BNP for AHF diagnosis in dyspneic patients and may provide additional clinical utility when BNP is difficult to interpret. MR-proADM identifies patients with high 90-day mortality risk and adds prognostic value to BNP. (Biomarkers in Acute Heart Failure [BACH]; NCT00537628)

Whilst it is formally stated that cardiac troponin is only released when cardiac myocytes undergo necrosis, there are a number of clinical situations where troponin is present in the circulation, without any apparent cardiac injury. In these cases, troponin half-life in the circulation is usually substantially shorter than that seen when troponin is released following myocardial infarction with frank necrosis. A mechanism has been described in liver, where large cytoplasmic molecules can pass from the intra- to extra-cellular space without cellular necrosis occurring. This occurs by the formation of membranous blebs which bud off from the plasma membrane of the cell. Blebs develop during cellular ischemia. If the ischemia is limited and re-oxygenation occurs, the blebs may be released into the circulation without rupture of the plasma membrane, resulting in a one-off release of cytoplasmic contents including macromolecules. Evidence from cardiac studies is presented supporting the presence of membranous blebs in cardiac myocytes, enabling troponin to be released from cardiac cells due to ischemia alone, without necrosis. Refereed/Peer-reviewed

Hypertension may affect the diagnostic performance of B-type natriuretic peptide (BNP). The objective of the present study was to assess the impact of a history of hypertension or blood pressure elevation on admission on the diagnostic performance of BNP in the diagnosis of heart failure (HF) in patients with acute dyspnea. BNP levels were measured using a rapid point-of-care device in 1,586 patients with acute dyspnea. In patients with HF, BNP levels did not differ between those with and without histories of hypertension. Conversely, in patients without HF, a history of hypertension was associated with higher median BNP levels (38 pg/ml [interquartile range 13 to 119] vs 21 pg/ml [interquartile range 7 to 64], p

The significance of troponin elevation and clinical utility of troponin testing in ambulatory patients with coronary artery disease (CAD) have not been examined. We sought to investigate the prevalence and prognostic value of cardiac troponin T (cTnT) elevation in a population with stable CAD.We studied 987 patients with stable CAD enrolled in the HeartSoul study who had plasma cTnT measurements before performing exercise treadmill testing.Of the studied population, 58 patients or 6.2% had detectable cTnT levels,or=0.01 ng/mL (0.01-0.72 ng/mL). During a mean follow-up period of 4.3 (0.1-6.5) years, 58.6% of participants with detectable cTnT had cardiovascular events compared with 22.5% of those without detectable cTnT (hazard ratio [HR] 3.8, 95% CI 2.6-5.4, P.001). This association remained strong after adjustment for traditional risk factors and C-reactive protein (HR 2.0, 95% CI 1.3-3.1, P = .002). However, after further adjustment for N-terminal pro-B-type natriuretic peptide and echocardiographic parameters of left ventricular function, cTnT elevation was not an independent predictor of cardiovascular events (HR 1.3, 95% CI, 0.8-2.3, P = .28).In ambulatory patients with stable CAD, the prevalence of cTnT elevation was 6.2%. Cardiac troponin T elevation detected using the conventional troponin assay was associated with increased risk of adverse cardiovascular outcomes, but its prognostic value was not incremental over N-terminal pro-B-type natriuretic peptide and echocardiographic evidence of cardiac abnormalities.

The development of highly sensitive cardiac troponin (cTnI) assays has increased the number of true and false positive results for patients suspected of acute myocardial infarction (AMI). Cases are reported whereby the use of serial testing, the 99th percentile cutoff, and the application of biological variation of cTnI were used to help determine ischemic vs. non-ischemic causes of myocardial injury.cTnI was measured using the Siemens Ultra assay from 13 representative patients who presented to the emergency department with symptoms suggestive of acute cardiac disease. Based on a previous study, reference change values of a 46% increase and 32% decrease were used to interpret results. These differences were compared against the patient's discharge diagnosis.Two patients who subsequently ruled in for AMI had a negative cTnI (0.04 microg/l) and borderline positive cTnI (0.07 microg/l) at admission, respectively. While the 4-6 h results were also borderline, there was a significant increase from the baseline (+575% and +50%, respectively) to suggest the presence of an acute cardiac event. Two other AMI cases document the significant cTnI decline in results after peak values. In 7 other non-AMI cases (heart and renal failure, gastrointestinal bleeding, stroke and venous thrombosis), while baseline concentrations were clearly positive (0.18-2.12 microg/l), subsequent serial samples were not significantly increased or decreased from baseline. These findings were not typical for AMI. There were 2 cases with acute blunt cardiac trauma and intracranial hemorrhage, respectively, that produced cTnI results that were initially low (0.04 and 0.05 microg/l, respectively), but significantly increased with serial testing thereby producing false positive Delta cTnI results for AMI.Serial testing for troponin was useful in differentiating early AMI from non-ischemic causes of troponin increases. However, non-AMI patients with acute cardiac injury can produce troponin results that mimic AMI. Therefore serial troponin testing must be used in conjunction with clinical presentation and other laboratory findings.

NT-proBNP measurements aid in the evaluation of patients with suspected heart failure (HF) and may facilitate risk stratification in patients with HF and acute coronary syndrome (ACS). Point-of-care (POC) assays may provide more timely results and potentially improve patient outcomes.We evaluated the analytical performance of the Response Biomedical Corporation whole blood RAMP amino-terminal pro-B type natriuretic peptide (NT-proBNP) POC assay compared to the Roche Elecsys proBNP (NT-proBNP) assay.Intra-day and total imprecision (% CV) ranged from 5.5% to 10.3% at 140, 449 and 1675 ng/L. The lowest concentration that yields a 20% CV was 57 ng/L. The lower limit of detection was 18 ng/L. The upper limit of linearity was validated to 23,428 ng/L with an average recovery of 95%. Correlation by Passing and Bablok regression yielded RAMP=1.01 Elecsys+14.6, r=0.98 (n=540; range of Elecsys values5 to35,000). Concordance of RAMP versus Elecsys using cut-offs of 125 ng/L for subjects75 years and 450 ng/L for subjectsor =75 was 92% (95% CI 89-94%) for a group consisting of 127 apparently healthy individuals and 208 non-healthy subjects without HF, and 99% (95% CI 97-100%) for patients with HF, using the New York Heart Association (NYHA) functional classification. Overall, 80%, 87%, 97% and 100% of the RAMP results and 77%, 85%, 96% and 100% of the Elecsys results were greater than the age appropriate cut-off for NYHA I, II, III or IV groups. For both the RAMP and Elecsys results, the median NT-proBNP value was statistically correlated (increasing) with NYHA I, II, III or IV groups, respectively (p0.0001), with no significant difference between the two methods.The POC Response Biomedical RAMP NT-proBNP assay provides comparable results that measured on the FDA cleared Roche Elecsys central laboratory platform.

Objectives The aim of this study was to examine the value of measurement of the interleukin-1 receptor family member ST2 in patients with dyspnea. Background Concentrations of ST2 have been reported to be elevated in patients with heart failure (HF). Methods Five hundred ninety-three dyspneic patients with and without acute destabilized HF presenting to an urban emergency department were evaluated with measurements of ST2 concentrations. Independent predictors of death at 1 year were identified. Results Concentrations of ST2 were higher among those with acute HF compared with those without (0.50 vs. 0.15 ng/ml; p Conclusions Among dyspneic patients with and without acute HF, ST2 concentrations are strongly predictive of mortality at 1 year and might be useful for prognostication when used alone or together with NT-proBNP.

Methanol and ethanol are primarily metabolized through the alcohol dehydrogenase (ADH) system in adults. Under saturating substrate concentrations, blood alcohol concentrations decline at a constant rate (i.e., zero-order kinetics). Minor metabolic alcohol pathways include oxidation through the cytochrome P450 system and catalase. We previously reported a 5-week-old infant that survived intoxication at an exceptional methanol concentration (1148 mg/dL). As the rate of elimination followed first-order kinetics, we proposed that an alternate non-saturating alcohol metabolizing enzyme system such as catalase was responsible for this observation. In this study, we developed and optimized enzyme immunoassays for tissue ADH and catalase, and measured the concentration of these enzymes in the livers of 18 adults and 7 perinatal infants obtained from autopsies. The mean ADH content of perinatal infants was approximately 10-fold lower than adults (0.11+/-0.09 g/kg versus 1.00+/-0.37 g/kg liver wet weight, respectively). The alphaalpha isoenzyme of ADH was the predominant isoform in perinatal infants, while there were several isoenzymes found in adult livers. For catalase, half of the perinatal infants (n=4) had roughly equal amounts as adults (0.32+/-0.03 g/kg versus 0.37+/-0.20 g/kg wet weight, p=NS), while three other perinatal infants had significantly higher concentrations (1.55+/-0.48 g/kg versus 0.37+/-0.02 g/kg wet weight, p

Background The first immunoassay was described by Berson and Yalow in 1959. Their work resulted in their receipt of the Nobel Prize in Medicine in 1977. Since this introduction, immunoassays have evolved considerably. Methods There have been several milestones that have led to the proliferation of modern immunoassays. The development of monoclonal antibodies from mouse hydridoma cells by Millstein and Kohler (Nobel Prize in 1984) enabled the production of high quantities of antibodies with well characterized epitope specificity. The first homogenous immunoassay (no separation step required) was the Enzyme Multiplied Immunoassay Technique (EMIT), which enabled adaptation of this assay onto automated chemistry platforms. EMIT was also one of the first immunoassay that made use of non-isotopic labels. Other non-isotopic labels became available such as chemiluminescence to improve the analytical sensitivity of immunoassays. The advantages of high-sensitivity immunoassays have created expanded diagnostic roles for some existing assays such as thyroid stimulating hormone for hyperthyroidism, C-reactive protein for cardiovascular risk assessment, and other applications. The development of instrumentation capable of automated heterogeneous immunoassays (separation step to improve sensitivity) has enabled movement of this technology from the “special chemistry” sections of a clinical laboratory into the "core" laboratory with other high-volume testing. Conclusion Today, immunoassays play a prominent role in the analysis of many clinical laboratory analytes such as proteins, hormones, drugs, and nucleic acids. The future involves development of assays with higher sensitivities which will enable the discovery of new biomarkers for disease diagnosis, and technology that will enable simultaneous multimarker analysis of tests whose needs are naturally grouped together (e.g., cytokines and allergens).

Background B-type natriuretic peptide (BNP) is valuable in diagnosing heart failure (HF), but its utility in obese patients is unknown. Studies have suggested a cut-point of BNP ≥100 pg/mL for the diagnosis of HF; however, there is an inverse relation between BNP levels and body mass index. We evaluated differential cut-points for BNP in diagnosing acute HF across body mass index levels to determine whether alternative cut-points can improve diagnosis. Methods The Breathing Not Properly Multinational Study was a 7-center, prospective study of 1586 patients who presented to the Emergency Department with acute dyspnea. B-type natriuretic peptide was measured on arrival. Height and weight data were available for 1368 participants. The clinical diagnosis of HF was adjudicated by 2 independent cardiologists who were blinded to BNP results. Results Heart failure was the final diagnosis in 46.1%. Mean BNP levels (pg/mL) in lean, overweight/obese, and severely/morbidly obese patients were 643, 462, and 247 for patients with acute HF, and 52, 35, and 25 in those without HF, respectively ( P Conclusions Body mass index influences the selection of cut-points for BNP in diagnosing acute HF. A lower cut-point (BNP ≥54 pg/mL) should be used in severely obese patients to preserve sensitivity. A higher cut-point in lean patients (BNP ≥170 pg/mL) could be used to increase specificity.

We examined the relation between B-type natriuretic peptide (BNP) levels and a history of stable angina pectoris and/or healed myocardial infarction in 1,240 patients who were evaluated in the emergency department for possible heart failure. In patients who had heart failure, there was no relation between BNP levels and previous stable angina pectoris and/or healed myocardial infarction. However, in patients who did not have heart failure, there was a relation between BNP levels and previous stable angina pectoris and/or healed myocardial infarction but no significant independent relation in multiple regression analysis.

Objectives This study was designed to assess the diagnostic performance of B-type natriuretic peptide (BNP) in the diagnosis of acute congestive heart failure (CHF) in patients with permanent/paroxysmal atrial fibrillation (AF) presenting with acute dyspnea. Background It is unknown to what extent AF affects the diagnostic performance of BNP in patients presenting with acute dyspnea. Methods We studied 1,431 patients drawn from a cohort of patients (n = 1,586) with acute dyspnea who had BNP levels measured on arrival. Patients were prospectively classified according to the presence or absence of permanent/paroxysmal AF. Results In total, 292 patients had permanent/paroxysmal AF. In patients without HF, permanent/paroxysmal AF was associated with significantly higher BNP levels (p = 0.001). Conversely, in patients with HF, BNP levels did not differ significantly between patients with and without AF (p = 0.533). A BNP cutoff value of 100 pg/ml had a specificity of 40% and 79% for the diagnosis of acute HF in patients with and without AF, respectively. The areas under the receiver-operating characteristic curves were 0.84 (95% confidence interval 0.78 to 0.89) and 0.91 (95% confidence interval 0.89 to 0.93) for patients with and without AF, respectively. Conclusions In patients without, but not in those with HF, the presence of AF is associated with higher circulating BNP levels, suggesting that a higher diagnostic threshold should be used in patients with AF.

Background Intravenous epinephrine (EPI) is used as a pharmacologic agent to acutely treat patients in cardiac arrest. Unfortunately, there have been several homicide cases where hospitalized patients died due to a purposeful overdose of epinephrine. We measured plasma epinephrine metabolites (metanephrine, MET, and normetanephrine, NMET) to determine if exogenous epinephrine can be distinguished from endogenous epinephrine concentrations in a controlled animal study. Methods Rabbits were subjected to three different protocols. In the physiologic stress group ( n =8), rabbits were immobilized for 30 min in a restraining tube. In the sub-lethal dose ( n =9), 0.01 mg/kg of epinephrine was injected into anesthetized rabbits. In the lethal dose group ( n =8), 1.0 mg/kg of epinephrine was administered into anesthetized rabbits. Blood was collected at regular intervals for up to 480 min. The plasma metanephrine and normetanephrine concentrations were measured by liquid chromatography/mass spectrometry and the serum cortisol concentrations by immunoassay. Results Serum cortisol and plasma metanephrine and normetanephrine concentrations increased in the stressed animals during immobilization demonstrating the endogenous stress model. Following a sub-therapeutic epinephrine dose, plasma metanephrine increased while plasma normetanephrine decreased. The peak plasma metanephrine concentrations were similar to the concentrations observed in the stressed animals; however, the ratio of plasma metanephrine to normetanephrine was significantly different. In the lethal epinephrine dose, both the plasma metanephrine concentrations and ratio of metabolites were significantly greater than those observed in the endogenously stressed animals. Conclusions The ratio of plasma metanephrine to normetanephrine is the best marker to determine the presence of exogenous therapeutic and lethal epinephrine administration. However, there were limitations to the study design that could alter these conclusions.

Plasma B-type natriuretic peptide (BNP) assays have become widely used to diagnose and manage patients with heart failure. However, differences in assay characteristics may have important implications when BNP is used as a screening test for heart failure at a specific cutoff value. We performed a prospective comparison of 2 commercially available assays—one that is a laboratory-based, microparticle enzyme immunoassay (MEIA) that uses EDTA plasma specimens and one that is a point-of-care (POC), single-use fluorescence immunoassay that uses EDTA-anticoagulated whole blood or plasma specimens—in patients with heart failure and healthy controls. Despite the overall concordance between different SNP assays for the diagnosis of heart failure, their sensitivities may differ when compared at the approved diagnostic cutoff value of 100 pg/mL. At this cutoff value, the MEIA on AxSYM® demonstrated greater sensitivity than POC Triage® BNP assay in minimally symptomatic patients with heart failure. Therefore, for screening purposes, cutoff values for plasma BNP or N-terminal pro-BNP levels should be specific for each assay to optimize test performance. These findings suggest that there is a relationship between the decision statistics used in screening for left ventricular dysfunction and the type of diagnostic assay used.

Background Some patients show warfarin resistance needing more than 70 mg of warfarin per week. In this study, we examined if C3435T polymorphism of MDR1 gene could be a factor of warfarin resistance. Methods We examined 196 blood specimens from the patients who took warfarin more than 42 mg/week for at least 1 year. The subjects consisted of 74 European Americans, 59 African Americans, 42 Hispanic Americans and 21 Asian Americans. Genotype of C3435T polymorphism was determined by using real-time polymerase chain reaction (PCR). Results Ninety (45.9%) of the 196 patients had C3435T genotype and the remaining patients had C3435C genotype (35.7%) and T3435T genotype (18.4%). Mean dose of warfarin of patients with C3435C, C3435T and T3435T genotypes were 59.5 mg/week, 56.9 mg/week and 55.6 mg/week, respectively. There was no statistical difference in the dose of warfarin between the 3 genotypes within each race. Conclusion Our results suggest that C3435T polymorphism of MDR1 gene is not associated with warfarin resistance.

B-type natriuretic peptide (BNP) is secreted from the cardiac ventricles in response to increased wall tension.The Breathing Not Properly Multinational Study was a 7-center, prospective study of 1586 patients who presented to the Emergency Department with acute dyspnea and had BNP measured with a point-of-care assay upon arrival. The gold standard for congestive heart failure (CHF) was adjudicated by two independent cardiologists, blinded to BNP results, who reviewed all clinical data and standardized scores. The current study explores the effect of these variables on BNP decision statistics as well as the impact that changing cutoffs might have on the cost-effectiveness of diagnostic decisions that use BNP information.Significant differences in CHF rates were found on the basis of age (P.001) and racial group (P =.020) but not sex (P =.424). BNP levels increased with increasing age (P.001). To evaluate potential differences in the diagnostic utility of BNP levels as a function of demographic variables, separate receiver operating characteristic curves were performed. BNP was a stronger predictor in younger subjects than in older subjects and slightly weaker for female patients than for male patients (area under the curve = 0.918 and 0.870, respectively). An even smaller difference was noted between the white and black racial groups (area under the curve = 0.888 and 0.903, respectively). The differences in specificity as a function of age are larger than other differences in specificity or sensitivity. When logistic regression was used in a multivariate approach to combine the demographic variables with BNP information in the prediction of CHF, only BNP contributed significantly to the prediction of acute CHF. When the model was expanded to include terms for the interaction of each of the demographic variables with log(10) BNP, a significant interaction was found for sex. Since the relative consequences of false-positives and false-negatives are unlikely to be equivalent, the BNP cut-points that would be selected based on the current data as a function of relative costs are presented. Sharply rising consequences are seen for BNP cut-points100 pg/mL.If one assumes that failing to treat cases of CHF is worse than treating negative cases, then relatively low BNP cut-points (eg, not100 pg/mL) should be used in patients presenting to the Emergency Department with a chief complaint of dyspnea, regardless of age, sex, or ethnicity.

Background: B-type natriuretic peptide (BNP) is a cardiac hormone that regulates hemodynamic equilibrium. In the circulation, its activity is controlled by proteolytic factors. Accurate measurement of BNP in a patient's plasma may be affected by degradation due to proteolysis. Objective: We report on the identification and performance of classes of protease inhibitors that stabilize BNP in plasma. Design and methods: Using the Bayer ADVIA Centaur® BNP assay, we measured the effect of arginine, serine and/or specific kallikrein protease inhibitors (PIs) on exogenous spiked or endogenous BNP in patient plasma. Results: Compared to controls without inhibitor, all PIs were capable, to varying degrees, of retarding the rate of proteolytic degradation. The kallikrein-specific inhibitor, d -Phe–Phe–Arg–chloromethylketone (PPACK II) was most effective as a single constituent and was able to eliminate BNP degradation in patient samples for up to 6–10 days when stored at 2–8 °C. Conclusions: The stability of BNP was markedly increased in the presence of kallikrein-specific PPACK II and a broad spectrum of serine PIs. Use of these compounds offers a simple method of extending sample handling and storage of plasma samples containing BNP.

Background : Brain natriuretic peptides (BNPs) are useful in the assessment of heart failure, left ventricular dysfunction, and acute coronary syndromes. Methods : We performed a multicenter evaluation of the automated Roche NT-proBNP assay and compared its performance to the Biosite Triage BNP assay. Results : The N-terminal (1–76) pro brain natriuretic peptide (NT-proBNP) method is precise (CV≤6.1%), has a wide dynamic measuring range (30–35,000 ng/l), is free from common interferences, and does not cross-react with BNP. EDTA or heparinized plasma samples collected in glass or plastic tubes can be used, and samples are stable at room temperature or 4 °C for up to 3 days. In contrast, the Biosite BNP assay has >2-fold higher CV, and plasma samples are more labile when stored at room temperature and 4 °C. Comparison studies showed a reasonable correlation between NT-proBNP and BNP assays, with a substantially higher slope bias of 6–20 for the NT-proBNP assay. Conclusions : The automated Roche NT-proBNP assay has good analytical performance and better precision than the Biosite BNP assay. Unlike BNP, NT-proBNP is stable in EDTA plasma for 3 days at room temperature or longer at 4 °C. The Roche NT-proBNP is fully automated and will accommodate the testing of large numbers of clinical samples for assessing cardiac dysfunction.

OBJECTIVES This study examines B-type natriuretic peptide (BNP) levels in patients with systolic versus non-systolic dysfunction presenting with shortness of breath. BACKGROUND Preserved systolic function is increasingly common in patients presenting with symptoms of congestive heart failure (CHF) but is still difficult to diagnose. METHODS The Breathing Not Properly Multinational Study was a seven-center, prospective study of 1,586 patients who presented with acute dyspnea and had BNP measured upon arrival. A subset of 452 patients with a final adjudicated diagnosis of CHF who underwent echocardiography within 30 days of their visit to the emergency department (ED) were evaluated. An ejection fraction of greater than 45% was defined as non-systolic CHF. RESULTS Of the 452 patients with a final diagnosis of CHF, 165 (36.5%) had preserved left ventricular function on echocardiography, whereas 287 (63.5%) had systolic dysfunction. Patients with non-systolic heart failure (NS-CHF) had significantly lower BNP levels than those with systolic heart failure (S-CHF) (413 pg/ml vs. 821 pg/ml, p < 0.001). As the severity of heart failure worsened by New York Heart Association class, the percentage of S-CHF increased, whereas the percentage of NS-CHF decreased. When patients with NS-CHF were compared with patients without CHF (n = 770), a BNP value of 100 pg/ml had a sensitivity of 86%, a negative predictive value of 96%, and an accuracy of 75% for detecting abnormal diastolic dysfunction. Using Logistic regression to differentiate S-CHF from NS-CHF, BNP entered first as the strongest predictor followed by oxygen saturation, history of myocardial infarction, and heart rate. CONCLUSIONS We conclude that NS-CHF is common in the setting of the ED and that differentiating NS-CHF from S-CHF is difficult in this setting using traditional parameters. Whereas BNP add modest discriminatory value in differentiating NS-CHF from S-CHF, its major role is still the separation of patients with CHF from those without CHF.

Signify® ER Drug Screen Test (Signify ER) and Triage® Drug of Abuse Panel plus TCA (Triage DOA Panel) rapid drug screening devices were compared at four laboratories. Both assay systems are point of care immunoassays, measuring phencyclidine, barbiturates, amphetamine, cocaine metabolite, methamphetamine, tricyclic antidepressants, opiates, marijuana metabolite, and benzodiazepines in human urine. The performance of these two assay systems, including a cutoff verification and cross-reactivity using spiked urine specimens and accuracy using clinical urine samples, was investigated. The cutoff verification study showed that the Signify ER had 95.4% precision for all drugs tested at concentrations of 50%, 75%, 125%, 150%, and 200% of cutoffs compared to 90% precision obtained with Triage DOA Panel. Accuracy studies testing 53 negative urine samples demonstrated that both Signify ER and Triage DOA Panel have 100% specificity. Testing of 693 positive urine samples demonstrated that Signify ER and Triage DOA Panel have sensitivities of 99.8% and 99.3%, respectively, with an accuracy of 99.9% and 99.6%. A total of 527 compounds were tested for the cross-reactivity study. Eighty-seven structurally related drugs and metabolites were found to cross-react with at least one of the nine tests of the Signify ER. Four hundred forty structurally unrelated compounds that can be found in human urine were shown not to cross-react with the Signify ER. In terms of operating characteristics, the Signify ER device is simpler since only a single pipetting step is required, and reaction completed within 8 min.

Objectives To determine the long-term biological variation (BV) of cardiac troponin I. Design and methods Three samples separated by a mean of 8.7 ± 2.8 months from 17 patients seen in an outpatient clinic. Tropoinin I was measured using a high sensitivity assay from Singulex, Inc. Results The long-term analytical, intra-assay and total variation were 15.2%, 27.9%, and 70.9%, respectively. The index of individuality (II) was 0.45, and the reference change value was + 98% and − 50%, respectively. Conclusion The BV over 9 months was comparable to previously published results over 2 months using the same testing methodology. The II indicates that reference range values are of less value than serial testing.

Background: In the absence of acute MI, cocaine use has not been significantly associated with elevations in serum troponin. The relationship between amphetamine and troponin levels remains unknown. Methods: Cross-sectional study of patients at a San Francisco emergency department who had cardiac

Background Molecular profiling assays have emerged as a promising tool in tumor diagnosis. Recent advances have allowed the use of formalin-fixed, paraffin-embedded (FFPE) tissues in such assays involving the use of microarrays. The Pathwork Tissue of Origin (TOO) Test was developed for use with FFPE tissue to aid tumor diagnosis. We sought to determine the performance of the TOO test on routine specimens from an independent laboratory. Methods Forty-five blinded, archived clinical specimens from the UCSF Department of Pathology were tested. Total RNA was processed to prepare labeled cDNA for hybridization to Pathchip microarrays. Hybridization data was analyzed with a 2000-gene classification model to quantify similarity between RNA expression of the study specimens and the 15 tissues on the test panel. Results 44/45 (98%) specimens were successfully processed. 37 cases met study inclusion criteria. Of these, 35 (95%) gave results which were in agreement with the reference diagnosis. In no case was the reference diagnosis ruled out. Conclusions The Tissue of Origin Test gave a high agreement with the reference diagnosis when archived clinical specimens from UCSF were assessed. Molecular profiling assays are highly accurate, and can be a useful tool in cancer diagnosis.

Adrenomedullin (ADM) is a vasodilatory peptide that has not been evaluated in large populations of patients presenting with chest pain. The CHOPIN trial (Copeptin Helps in the early detection Of Patients with acute myocardial Infarction) was a 16-center trial which enrolled 2071 patients who