Citations

Abstract The International Federation of Clinical Chemistry Committee on Clinical Application of Cardiac Bio-Markers provides evidence-based educational documents to facilitate uniform interpretation and utilization of cardiac biomarkers in clinical laboratories and practice. The committee’s goals are to improve the understanding of certain key analytical and clinical aspects of cardiac biomarkers and how these may interplay in clinical practice. Measurement of high-sensitivity cardiac troponin (hs-cTn) assays is a cornerstone in the clinical evaluation of patients with symptoms and/or signs of acute cardiac ischemia. To define myocardial infarction, the Universal Definition of Myocardial Infarction requires patients who manifest with features suggestive of acute myocardial ischemia to have at least one cTn concentration above the sex-specific 99th percentile upper reference limit (URL) for hs-cTn assays and a dynamic pattern of cTn concentrations to fulfill the diagnostic criteria for MI. This special report provides an overview of how hs-cTn 99th percentile URLs should be established, including recommendations about prescreening and the number of individuals required in the reference cohort, how statistical analysis should be conducted, optimal preanalytical and analytical protocols, and analytical/biological interferences or confounds that can affect accurate determination of the 99th percentile URLs. This document also provides guidance and solutions to many of the issues posed.

Abstract Aims Limited US outcome data exist among patients with myocardial injury and types 1 and 2 myocardial infarction (MI) evaluated with high-sensitivity cardiac troponin (hs-cTn). Methods and results This is an observational US cohort study of emergency department (ED) patients undergoing hs-cTnT measurement. Cases with ≥1 hs-cTnT increase >99th percentile were adjudicated following the Fourth Universal Definition of MI. Post-discharge major adverse cardiovascular events (MACE) included death, MI, heart failure (HF) hospitalization, stroke or transient ischaemic attack, and new-onset atrial fibrillation or flutter during 2 years follow-up. Among 2002 patients, 857 (43%) had ≥1 hs-cTnT >99th percentile. Among these, 702 (81.9%) had myocardial injury, 64 (7.5%) had type 1 MI, and 91 (10.6%) had type 2 MI. Compared with patients without myocardial injury, type 2 MI [8.4 vs. 50%; adjusted hazard ratio (HR) 2.31, 95% confidence interval (CI) 1.49–3.58] and myocardial injury (8.4 vs. 47%; adjusted HR 3.13, 95% CI 2.39–4.09) had a higher risk of MACE, in large part because of death and HF hospitalizations. Compared with patients with type 1 MI, type 2 MI (23 vs. 50%; adjusted HR 2.24; 95% CI 1.23–4.10) and myocardial injury (23 vs. 47%; adjusted HR 2.02; 95% CI 1.20–3.40) also have a higher risk of MACE. Conclusion Among unselected US ED patients undergoing hs-cTnT measurement, most increases are due to myocardial injury, and type 2 MI is more frequent than type 1 MI. Patients with myocardial injury and type 2 MI have morbid outcomes, in large part due to death and HF.

Abstract Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.

Abstract Peripheral T-cell lymphomas (PTCLs) are heterogenous T-cell neoplasms often associated with epigenetic dysregulation. We investigated de novo DNA methyltransferase 3A (DNMT3A) mutations in common PTCL entities, including angioimmunoblastic T-cell lymphoma and novel molecular subtypes identified within PTCL–not otherwise specified (PTCL-NOS) designated as PTCL-GATA3 and PTCL-TBX21. DNMT3A-mutated PTCL-TBX21 cases showed inferior overall survival (OS), with DNMT3A-mutated residues skewed toward the methyltransferase domain and dimerization motif (S881–R887). Transcriptional profiling demonstrated significant enrichment of activated CD8+ T-cell cytotoxic gene signatures in the DNMT3A-mutant PTCL-TBX21 cases, which was further validated using immunohistochemistry. Genomewide methylation analysis of DNMT3A-mutant vs wild-type (WT) PTCL-TBX21 cases demonstrated hypomethylation in target genes regulating interferon-γ (IFN-γ), T-cell receptor signaling, and EOMES (eomesodermin), a master transcriptional regulator of cytotoxic effector cells. Similar findings were observed in a murine model of PTCL with Dnmt3a loss (in vivo) and further validated in vitro by ectopic expression of DNMT3A mutants (DNMT3A-R882, -Q886, and -V716, vs WT) in CD8+ T-cell line, resulting in T-cell activation and EOMES upregulation. Furthermore, stable, ectopic expression of the DNMT3A mutants in primary CD3+ T-cell cultures resulted in the preferential outgrowth of CD8+ T cells with DNMT3AR882H mutation. Single-cell RNA sequencing(RNA-seq) analysis of CD3+ T cells revealed differential CD8+ T-cell subset polarization, mirroring findings in DNMT3A-mutated PTCL-TBX21 and validating the cytotoxic and T-cell memory transcriptional programs associated with the DNMT3AR882H mutation. Our findings indicate that DNMT3A mutations define a cytotoxic subset in PTCL-TBX21 with prognostic significance and thus may further refine pathological heterogeneity in PTCL-NOS and suggest alternative treatment strategies for this subset.

Background: There are good data to support using a single high-sensitivity cardiac troponin T (hs-cTnT) below the limit of detection of 5 ng/L to exclude acute myocardial infarction. Per the US Food and Drug Administration, hs-cTnT can only report to the limit of quantitation of 6 ng/L, a threshold for which there are limited data. Our goal was to determine whether a single hs-cTnT below the limit of quantitation of 6 ng/L is a safe strategy to identify patients at low risk for acute myocardial injury and infarction. Methods: The efficacy (proportion identified as low risk based on baseline hs-cTnT<6 ng/L) of identifying low-risk patients was examined in a multicenter (n=22 sites) US cohort study of emergency department patients undergoing at least 1 hs-cTnT (CV Data Mart Biomarker cohort). We then determined the performance of a single hs-cTnT<6 ng/L (biomarker alone) to exclude acute myocardial injury (subsequent hs-cTnT >99th percentile in those with an initial hs-cTnT<6 ng/L). The clinically intended rule-out strategy combining a nonischemic ECG with a baseline hs-cTnT<6 ng/L was subsequently tested in an adjudicated cohort in which the diagnostic performance for ruling out acute myocardial infarction and safety (myocardial infarction or death at 30 days) were evaluated. Results: A total of 85 610 patients were evaluated in the CV Data Mart Biomarker cohort, among which 24 646 (29%) had a baseline hs-cTnT<6 ng/L. Women were more likely than men to have hs-cTnT<6 ng/L (38% versus 20%, P <0.0001). Among 11 962 patients with baseline hs-cTnT<6 ng/L and serial measurements, only 1.2% developed acute myocardial injury, resulting in a negative predictive value of 98.8% (95% CI, 98.6–99.0) and sensitivity of 99.6% (95% CI, 99.5–99.6). In the adjudicated cohort, a nonischemic ECG with hs-cTnT<6 ng/L identified 33% of patients (610/1849) as low risk and resulted in a negative predictive value and sensitivity of 100% and a 30-day rate of 0.2% for myocardial infarction or death. Conclusions: A single hs-cTnT below the limit of quantitation of 6 ng/L is a safe and rapid method to identify a substantial number of patients at very low risk for acute myocardial injury and infarction.

Troponin is the biomarker of choice for the diagnosis of myocardial infarction (MI) in clinical practice. Data on its value to predict death, while documented in clinical trials, are lacking from community studies. There is little information from population studies of MI on short and long term predictive value of Troponin on death and nonfatal endpoints such as recurrent ischemic events and heart failure. Methods: We evaluated the prognostic value of Troponin T (TnT) among consecutive persons with incident MI in Olmsted County, MN. Results: 1220 persons (mean age 69±15 years, 45% women) experienced an incident MI (20% ST elevation MI) in Olmsted County, MN between 2002 and 2008. Peak TnT value measured at a median of 1 day post-MI was 1.88±4.19 ng/mL (median 0.52 (25%: 0.16, 75%: 1.75)). After 1.27 years of follow-up, 294 deaths occurred, 360 recurrent ischemic events (recurrent MI or hospitalized unstable angina) and 345 episodes of heart failure. Associations between clinical events and TnT tertiles are shown in the table . Conclusions: In the community, the magnitude of TnT elevation is predictive of recurrent ischemic events, heart failure and early death. It is not associated with long-term mortality. Hazard ratio compared to lowest TnT tertile, 95%CI and p value Adjusted for age, sex and comorbidity Outcome All events Events within 30 days Events among 30 day survivors Death TnT tertile 2 TnT tertile 3 p-value 1.02 (0.78-1.33) 1.15 (0.85-1.57) 0.64 0.64 (0.38-1.06) 1.59 (0.98-2.57) 0.004 1.24 (0.90-1.69) 0.93 (0.62-1.38) 0.26 Recurrent ischemic events TnT tertile 2 TnT tertile 3 p-value 1.45 (1.12-1.88) 1.70 (1.29-2.24) <0.001 1.45 (0.96-2.19) 2.07 (1.37-3.12) 0.002 1.46 (1.05-2.04) 1.45 (1.00-2.10) 0.049 Heart failure TnT tertile 2 TnT tertile 3 p-value 1.03 (0.78-1.36) 2.10 (1.58-2.78) <0.001 0.94 (0.68-1.29) 2.10 1.54-2.87) <0.001 1.38 (0.79-2.41) 2.19 (1.14-4.21) 0.067

Introduction: Plasma ceramides (CER) are sphingolipids associated with adverse events and mortality in patients with established coronary artery disease (CAD) and/or risk factors for CAD. The ability of these same specific ratios of CER to predict major adverse cardiovascular events (MACE) in subjects without CAD in the community is less certain. We tested the hypothesis that CER are associated with MACE in a community-based cohort free of CAD at enrollment. Methods: In a prospective community-based cohort we performed passive follow-up using a record linkage system to ascertain the composite outcome of MACE, defined as acute myocardial infarction, coronary revascularization (coronary artery bypass grafting or percutaneous coronary intervention), stroke or death. CER were analyzed as continuous variables, ratios and quintiles adjusting for potential confounders. Results: We included 1221 subjects, 49% males, mean age ± (SD) 61.1±9.6 years. After a median follow-up of 16 years (IQR 1.7), 297 patients had a MACE: Myocardial infarction (105), coronary artery bypass surgery (53), percutaneous coronary intervention (92), stroke (137) and all-cause death (120). Some had more than one event. Ratios of CER were significantly associated with MACE in unadjusted and adjusted models, see Figure 1-A. This association was independent of LDL-C, total cholesterol, Apo-B and traditional CAD risk factors. Those in the highest quintile of (24:1/24:0) CER ratio had more than two-fold risk of MACE, HR 2.32 (95% CI, 1.59-3.46). There was a dose-response association across quintiles of CER ratios and MACE, Figure 1-B.: Conclusions: Elevated CER plasma ratios are associated with MACE in patients with no CAD in the community. The risk conferred by plasma CER is independent of traditional risk factors, including lipids, and has a dose-response.

Background Elevated plasma ceramides are independent predictors of cardiovascular disease and mortality in patients with advanced epicardial coronary artery disease. Our understanding of plasma ceramides in early epicardial coronary artery disease, however, remains limited. We examined the role of plasma ceramides in early coronary atherosclerosis characterized by coronary endothelial dysfunction. Methods and Results Participants presenting with chest pain and nonobstructive epicardial coronary artery disease underwent coronary endothelial function. Patients (n=90) demonstrated abnormal coronary endothelial function with acetylcholine (≥20% decrease in coronary artery diameter or ≤50% increase in coronary blood flow). A total of 30 controls had normal coronary endothelial function. Concentrations of plasma ceramide 18:0 ( P =0.038), 16:0 ( P =0.021), and 24:0 ( P =0.019) differed between participants with normal and abnormal coronary endothelial function. Ceramide 24:0 (odds ratio [OR], 2.23 [95% CI, 1.07–4.66]; P =0.033) and 16:0 (OR, 1.91×10 6 [95% CI, 11.93–3.07×10 11 ]; P =0.018) were independently associated with coronary endothelial dysfunction. Among participants with endothelium‐dependent coronary dysfunction (n=78), ceramides 16:0 (OR, 5.17×10 5 [95% CI, 2.83–9.44×10 10 ]; P =0.033), 24:0 (OR, 2.98 [95% CI, 1.27–7.00]; P =0.012), and 24:1/24:0 (OR, 4.39×10 −4 [95% CI, 4×10 −7 –0.48]; P =0.030) were more likely to be elevated. Conclusions The current study demonstrated an association between increased circulating ceramide levels and coronary endothelial dysfunction in the absence of epicardial coronary artery disease. This study supports the role of plasma ceramides as a potential biomarker or a therapeutic target for early coronary atherosclerosis in humans.