Prediction of outcome by highly sensitive troponin T in outpatients with chronic systolic left ventricular heart failure

Association of high-sensitivity troponin T with left ventricular dysfunction in prediabetes

BACKGROUND

Impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) are an increasingly serious problem worldwide. Tissue Doppler imaging (TDI), a non-invasive technique, may evaluate both systolic and diastolic function during the first phases of cardiovascular disease (CVD). High-sensitivity cardiac troponin T (hs-cTnT) can detect subclinical myocardial injury in asymptomatic prediabetic patients.

AIM

We aimed to investigate the relationship between left ventricular (LV) function and hs-cTnT in prediabetic patients.

METHODS

Between 1 October 2021 and 1 October 2022, we recruited 96 prediabetic and an equal number of age- and gender-matched healthy volunteers prospectively. TDI was used to evaluate both systolic and diastolic functions. Hs-cTnT levels were obtained and compared between groups.

RESULTS

It was found that the values for mitral annular plane systolic excursion (MAPSE), E, the rapid filling wave, E/Em, and the peak annular velocities of systolic excursion in the ejection period (Sm) were all significantly higher in these patients compared to healthy individuals (p < .001). Hs-cTnT was an independent predictor of left ventricular diastolic dysfunction (LVDD) and left ventricular systolic dysfunction (LVSD) (odds ratio [OR] = 2.625, 95% confidence interval [CI] = 1.324-4.308, p < .001, and OR = 1.922, 95% CI = 0.454-3.206, p = .004).

CONCLUSIONS

Prediabetics had higher hs-cTnT levels than controls. We showed that LVSD and LVDD functions were negatively affected in prediabetic patients. Our results proved that hs-cTnT levels may be associated with subclinical LV dysfunction in prediabetes.

NT-proBNP for Risk Prediction in Heart Failure: Identification of Optimal Cutoffs Across Body Mass Index Categories

OBJECTIVES

The goal of this study was to assess the predictive power of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and the decision cutoffs in heart failure (HF) across body mass index (BMI) categories.

BACKGROUND

Concentrations of NT-proBNP predict outcome in HF. Although the influence of BMI to reduce levels of NT-proBNP is known, the impact of obesity on prognostic value remains uncertain.

METHODS

Individual data from the BIOS (Biomarkers In Heart Failure Outpatient Study) consortium were analyzed. Patients with stable HF were classified as underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5-24.9 kg/m²), overweight (BMI 25-29.9 kg/m²), and mildly (BMI 30-34.9 kg/m²), moderately (BMI 35-39.9 kg/m²), or severely (BMI ≥40 kg/m²) obese. The prognostic role of NT-proBNP was tested for the endpoints of all-cause and cardiac death.

RESULTS

The study population included 12,763 patients (mean age 66 ± 12 years; 25% women; mean left ventricular ejection fraction 33% ± 13%). Most patients were overweight (n = 5,176), followed by normal weight (n = 4,299), mildly obese (n = 2,157), moderately obese (n = 612), severely obese (n = 314), and underweight (n = 205). NT-proBNP inversely correlated with BMI (β = -0.174 for 1 kg/m²; P < 0.001). Adding NT-proBNP to clinical models improved risk prediction across BMI categories, with the exception of severely obese patients. The best cutoffs of NT-proBNP for 5-year all-cause death prediction were lower as BMI increased (3,785 ng/L, 2,193 ng/L, 1,554 ng/L, 1,045 ng/L, 755 ng/L, and 879 ng/L, for underweight, normal weight, overweight, and mildly, moderately, and severely obese patients, respectively) and were higher in women than in men.

CONCLUSIONS

NT-proBNP maintains its independent prognostic value up to 40 kg/m² BMI, and lower optimal risk-prediction cutoffs are observed in overweight and obese patients.

Concentration-dependent clinical and prognostic importance of high-sensitivity cardiac troponin T in heart failure and a reduced ejection fraction and the influence of empagliflozin: the EMPEROR-Reduced trial

Aims

Circulating troponin is an important measure of risk in patients with heart failure, but it has not been used to determine if disease severity influences the responses to drug treatments in randomized controlled trials.

Methods and results

In the EMPEROR‐Reduced trial, patients with class II–IV heart failure and a reduced ejection fraction were randomly assigned to placebo or empagliflozin 10 mg daily and followed for the occurrence of serious heart failure and renal events. High‐sensitivity cardiac troponin T (hs‐cTnT) was measured in 3636 patients (>97%) at baseline, and patients were divided into four groups based on the degree of troponin elevation. With increasing concentrations of hs‐cTnT, patients were progressively more likely to have diabetes and atrial fibrillation, to have New York Heart Association class III–IV symptoms and been hospitalized for heart failure within the prior year, and to have elevated levels of natriuretic peptides and worse renal function (P‐trend < 0.0001 for all comparisons), but importantly, the troponin groups did not differ with respect to ejection fraction. A linear relationship was observed between the logarithm of hs‐cTnT and the combined risk of cardiovascular death or hospitalization for heart failure (P = 0.0015). When treated with placebo, patients with the highest levels of hs‐cTnT had risks of cardiovascular death and hospitalization for heart failure that were 3–5 fold greater than those with values in the normal range. Patients with higher levels of hs‐cTnT were also more likely to experience worsening of renal function and serious adverse renal events and showed the least improvement in health status (as measured by the Kansas City Cardiomyopathy Questionnaire). When compared with placebo, empagliflozin reduced the combined risk of cardiovascular death or hospitalization for heart failure, regardless of the baseline level of hs‐cTnT, whether the effects of treatment were analysed as hazard ratios or absolute risk reductions.

Conclusions

Elevations in hs‐cTnT reflect the clinical severity, stability and prognosis of patients with heart failure and a reduced ejection fraction, with biomarkers, comorbidities, clinical course and risks that are proportional to the magnitude of hs‐cTnT elevation. Empagliflozin exerted favourable effects on heart failure and renal outcomes, regardless of the baseline concentration of hs‐cTnT.

A Test in Context: Interpretation of High-Sensitivity Cardiac Troponin Assays in Different Clinical Settings

High-sensitivity cardiac troponin (hs-cTn) assays have the ability to detect minute troponin concentrations and resolve minor changes in biomarker concentrations. Clinically, this allows for the ability to rapidly identify or exclude acute myocardial injury in the setting of acute chest discomfort-thus providing more rapid evaluation for acute myocardial infarction-but the improvements in troponin assays also create avenues for other applications where troponin release from the cardiomyocyte might confer prognostic information. These situations include cardiovascular risk assessment across a wide range of clinical circumstances, including apparently-well individuals, those at risk for heart disease, and those with prevalent cardiovascular disorders. The optimal hs-cTn threshold for each circumstance varies by the assay used and by the population assessed. This review will provide context for how hs-cTn assays might be interpreted depending on the application sought, reviewing results from studies leveraging hs-cTn for applications beyond "acute myocardial infarction diagnostic evaluation."

Incremental prognostic value of a novel metabolite-based biomarker score in congestive heart failure patients

Aims

The Cardiac Lipid Panel (CLP) is a newly discovered panel of metabolite‐based biomarkers that has shown to improve the diagnostic value of N terminal pro B type natriuretic peptide (NT‐proBNP). However, little is known about its usefulness in predicting outcomes. In this study, we developed a risk score for 4‐year cardiovascular death in elderly chronic heart failure (CHF) patients using the CLP.

Methods and results

From the Cardiac Insufficiency Bisoprolol Study in Elderly trial, we included 280 patients with CHF aged >65 years. A targeted metabolomic analysis of the CLP biomarkers was performed on baseline serum samples. Cox regression was used to determine the association of the biomarkers with the outcome after accounting for established risk factors. A risk score ranging from 0 to 4 was calculated by counting the number of biomarkers above the cut‐offs, using Youden index. During the mean (standard deviation) follow‐up period of 50 (8) months, 35 (18%) subjects met the primary endpoint of cardiovascular death. The area under the receiver operating curve for the model based on clinical variables was 0.84, the second model with NT‐proBNP was 0.86, and the final model with the CLP was 0.90. The categorical net reclassification index was 0.25 using three risk categories: 0–60% (low), 60–85% (intermediate), and >85% (high). The continuous net reclassification index was 0.772, and the integrated discrimination index was 0.104.

Conclusions

In patients with CHF, incorporating a panel of three metabolite‐based biomarkers into a risk score improved the prognostic utility of NT‐proBNP by predicting long‐term cardiovascular death more precisely. This novel approach holds promise to improve clinical risk assessment in CHF patients.

True 99th centile of high sensitivity cardiac troponin for hospital patients: prospective, observational cohort study

OBJECTIVE

To determine the distribution, and specifically the true 99th centile, of high sensitivity cardiac troponin I (hs-cTnI) for a whole hospital population by applying the hs-cTnI assay currently used routinely at a large teaching hospital.

DESIGN

Prospective, observational cohort study.

SETTING

University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom, between 29 June 2017 and 24 August 2017.

PARTICIPANTS

20 000 consecutive inpatients and outpatients undergoing blood tests for any clinical reason. Hs-cTnI concentrations were measured in all study participants and nested for analysis except when the supervising doctor had requested hs-cTnI for clinical reasons.

MAIN OUTCOME MEASURES

Distribution of hs-cTnI concentrations of all study participants and specifically the 99th centile.

RESULTS

The 99th centile of hs-cTnI for the whole population was 296 ng/L compared with the manufacturer's quoted level of 40 ng/L (currently used clinically as the upper limit of normal; ULN). Hs-cTnI concentrations were greater than 40 ng/L in one in 20 (5.4%, n=1080) of the total population. After excluding participants diagnosed as having acute myocardial infarction (n=122) and those in whom hs-cTnI was requested for clinical reasons (n=1707), the 99th centile was 189 ng/L for the remainder (n=18 171). The 99th centile was 563 ng/L for inpatients (n=4759) and 65 ng/L for outpatients (n=9280). Patients from the emergency department (n=3706) had a 99th centile of 215 ng/L, with 6.07% (n=225) greater than the recommended ULN. 39.02% (n=48) of all patients from the critical care units (n=123) and 14.16% (n=67) of all medical inpatients had an hs-cTnI concentration greater than the recommended ULN.

CONCLUSIONS

Of 20 000 consecutive patients undergoing a blood test for any clinical reason at our hospital, one in 20 had an hs-cTnI greater than the recommended ULN. These data highlight the need for clinical staff to interpret hs-cTnI concentrations carefully, particularly when applying the recommended ULN to diagnose acute myocardial infarction, in order to avoid misdiagnosis in the absence of an appropriate clinical presentation.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03047785.

Cardiac Troponin - diagnostic problems and impact on cardiovascular disease

The definition of a high-sensitivity cardiac Troponin (cTn) assay describes the ability to quantify a cardiac biomarker level in at least 50% of healthy individuals. This advance in analytic sensitivity has come with a perceived loss of specificity in the most classic application - chest pain triage and the diagnosis of acute myocardial infarction (AMI). As cardiac Troponin can no longer be used as a dichotomous test, the medical field is increasingly moving towards a more granular interpretation. However, rapid rule-out/rule-in algorithms for AMI still rely on concrete thresholds for efficient triage, irrespective of the patient's comorbidities. Owing to a slightly elevated cTn value, evermore patients appear to fall into an indeterminate risk zone of diagnostic uncertainty. The reasons are manifold, spanning biological variation, analytical issues, increased plasma membrane permeability and the potential cytosolic release of cTn. This review provides a contemporary overview of the literature concerning the use of cardiac Troponin in chronic and acute cardiovascular care. Key messages High-sensitivity cardiac Troponin assays have transformed the assessment of cardiovascular disease. Rapid rule-out algorithms for chest pain triage have become increasingly complicated, but enable safe rule-out. Cardiac Troponin tracks mid- to long-term risk in patients with hyperlipidaemia, heart failure and renal dysfunction.

Association of High-Sensitivity Troponin T With Left Ventricular Dysfunction in Ankylosing Spondylitis

BACKGROUND

Ankylosing spondylitis (AS) is a systemic inflammatory disease, and cardiac dysfunction has not been clearly described clinically. High-sensitivity cardiac troponin T (hs-cTnT) is a noninvasive marker for subclinical myocardial injury.

OBJECTIVE

In this study, we aimed to investigate any relationship between hs-cTnT and left ventricular (LV) function evaluated via tissue Doppler imaging in AS patients with no known cardiac risk factor.

METHODS

Our study used a cross-sectional case protocol design and was conducted between January 2016 and June 2016. In total, 40 AS patients (17 females and 23 males) were age and sex matched with healthy volunteers (20 females and 20 males) and enlisted for this study. Detailed transthoracic echocardiography was performed, and tissue Doppler imaging was used to assess systolic and diastolic functions. High-sensitivity cardiac troponin T levels were measured and compared between 2 groups.

RESULTS

Compared with control subjects, AS patients had lower early (Em)/late (Am) diastolic myocardial velocities, mitral annular plane systolic excursion, and end-diastolic distance from the mitral annulus to the LV apex. Conversely, they had greater systolic myocardial velocity (Sm), isovolumetric relaxation time, and displacement index (p < 0.001, for all). Higher hs-cTnT levels were measured in AS patients (0.45 ± 0.22 vs. 1.11 ± 0.27, p < 0.001), and multivariate logistic regression analyses revealed that hs-cTnT was an independent predictor of LV diastolic dysfunction in AS patients.

CONCLUSIONS

These data show that AS patients had impaired LV functions and increased hs-cTnT levels. Tissue Doppler imaging may be a useful tool for detection of early functional LV abnormalities, and hs-cTnT may be valuable biomarker of diastolic LV dysfunction in AS patients.

High-sensitivity troponin T, NT-proBNP and glomerular filtration rate: A multimarker strategy for risk stratification in chronic heart failure

BACKGROUND

In a recent individual patient data meta-analysis, high-sensitivity troponin T (hs-TnT) emerged as robust predictor of prognosis in stable chronic heart failure (HF). In the same population, we compared the relative predictive performances of hs-TnT, N-terminal fraction of pro-B-type natriuretic peptide (NT-proBNP), hs-C-reactive protein (hs-CRP), and estimated glomerular filtration rate (eGFR) for prognosis.

METHODS AND RESULTS

9289 patients (66 ± 12 years, 77% men, 85% LVEF <40%, 60% ischemic HF) were evaluated over a 2.4-year median follow-up. Median eGFR was 58 mL/min/1.73 m² (interquartile interval 46-70; n = 9220), hs-TnT 16 ng/L (8-20; n = 9289), NT-proBNP 1067 ng/L (433-2470; n = 8845), and hs-CRP 3.3 mg/L (1.4-7.8; n = 7083). In a model including all 3 biomarkers, only hs-TnT and NT-proBNP were independent predictors of all-cause and cardiovascular mortality and cardiovascular hospitalization. hs-TnT was a stronger predictor than NT-proBNP: for example, the risk for all-cause death increased by 54% per doubling of hs-TnT vs. 24% per doubling of NT-proBNP. eGFR showed independent prognostic value from both hs-TnT and NT-proBNP. The best hs-TnT and NT-proBNP cut-offs for the prediction of all-cause death increased progressively with declining renal function (eGFR ≥ 90: hs-TnT 13 ng/L and NT-proBNP 825 ng/L; eGFR < 30: hs-TnT 40 ng/L and NT-proBNP 4608 ng/L). Patient categorization according to these cut-offs effectively stratified patient prognosis across all eGFR classes.

CONCLUSIONS

hs-TnT conveys independent prognostic information from NT-proBNP, while hs-CRP does not. Concomitant assessment of eGFR may further refine risk stratification. Patient classification according to hs-TnT and NT-proBNP cut-offs specific for the eGFR classes holds prognostic significance.

Heart Failure with Reduced Ejection Fraction in Women: Epidemiology, Outcomes, and Treatment

There are millions of people affected by heart failure with reduced ejection fraction (HFrEF) as diagnosed with ejection fraction 40% or less by imaging. Established therapies have been proven through clinical trials on lifestyle interventions, medications, and devices for HFrEF to improve quality of life, heart function, and survival. Although there are more men than women suffering with HFrEF, there are no prospectively proven, sex-specific guideline therapies because women have been underrepresented in clinical trials. Current recommendations for medications in women with HFrEF are described in this article.

Prognostic Value of High-Sensitivity Troponin T in Chronic Heart Failure

Background:

Most patients with chronic heart failure have detectable troponin concentrations when evaluated by high-sensitivity assays. The prognostic relevance of this finding has not been clearly established so far. We aimed to assess high-sensitivity troponin assay for risk stratification in chronic heart failure through a meta-analysis approach.

Methods:

Medline, EMBASE, Cochrane Library, and Scopus were searched in April 2017 by 2 independent authors. The terms were “troponin” AND “heart failure” OR “cardiac failure” OR “cardiac dysfunction” OR “cardiac insufficiency” OR “left ventricular dysfunction.” Inclusion criteria were English language, clinical stability, use of a high-sensitivity troponin assay, follow-up studies, and availability of individual patient data after request to authors. Data retrieved from articles and provided by authors were used in agreement with the PRISMA statement. The end points were all-cause death, cardiovascular death, and hospitalization for cardiovascular cause.

Results:

Ten studies were included, reporting data on 11 cohorts and 9289 patients (age 66±12 years, 77% men, 60% ischemic heart failure, 85% with left ventricular ejection fraction <40%). High-sensitivity troponin T data were available for all patients, whereas only 209 patients also had high-sensitivity troponin I assayed. When added to a prognostic model including established risk markers (sex, age, ischemic versus nonischemic etiology, left ventricular ejection fraction, estimated glomerular filtration rate, and N-terminal fraction of pro-B-type natriuretic peptide), high-sensitivity troponin T remained independently associated with all-cause mortality (hazard ratio, 1.48; 95% confidence interval, 1.41–1.55), cardiovascular mortality (hazard ratio, 1.40; 95% confidence interval, 1.33–1.48), and cardiovascular hospitalization (hazard ratio, 1.42; 95% confidence interval, 1.36–1.49), over a median 2.4-year follow-up (all P <0.001). High-sensitivity troponin T significantly improved risk prediction when added to a prognostic model including the variables above. It also displayed an independent prognostic value for all outcomes in almost all population subgroups. The area under the curve–derived 18 ng/L cutoff yielded independent prognostic value for the 3 end points in both men and women, patients with either ischemic or nonischemic etiology, and across categories of renal dysfunction.

Conclusions:

In chronic heart failure, high-sensitivity troponin T is a strong and independent predictor of all-cause and cardiovascular mortality, and of hospitalization for cardiovascular causes, as well. This biomarker then represents an additional tool for prognostic stratification.

High sensitivity troponins in contemporary cardiology practice: are we turning a corner?

INTRODUCTION

Troponin is considered to be the gold standard biomarker for ruling out MI. There has been a drive to improve the diagnostic speed, and as such the high sensitivity cardiac troponin (hs-cTn) assays have been introduced into clinical practice and are now part of international guidelines. Their novel value in clinical practice more generally is becoming apparent. Areas covered: In this review we will evaluate the evidence for the use of hs-cTn assays in clinical practice, the issues with the assay and how the hs-cTn can be utilized in the future as a biomarker of cardiovascular risk. Expert commentary: The use of the hs-cTn assays as a 'rule out' test for MI is compelling, as a 'rule in' there are significant issues relating the specificity of the assay for MI. The future of the assay may lie in population screening and risk modeling.

Impact of Sex on Cardiac Troponin Concentrations—A Critical Appraisal

BACKGROUND

The use of sex-specific cutoffs for cardiac troponin (cTn) is currently debated. Although endorsed by scientific working groups, concerns have been raised that sex-specific cutoffs may have only a small clinical effect at the cost of increased complexity in decision-making.

METHODS

We reviewed studies investigating the interrelations between high-sensitivity (hs) cTn results and sex, diagnoses, and outcome. Investigated populations included community-dwelling subjects and patients with stable angina, congestive heart failure, or acute chest pain including those with acute coronary syndromes.

RESULTS

Men usually have higher hs-cTn concentrations compared with women, regardless of the assessed population or the applied assay. The distribution and prognostic implications of hs-cTn concentrations indicate that women have a broader cardiovascular risk panorama compared with men, particularly at lower hs-cTn concentrations. At higher concentrations, particularly above the 99th percentile, this variation is often attenuated. Sex-specific hs-cTn 99th percentiles have so far shown clinical net benefit in only 1 study assessing patients with chest pain. However, several methodological aspects need to be considered when interpreting study results, e.g., issues related to the determination of the 99th percentiles, the selection bias, and the lack of prospective and sufficiently powered analyses.

CONCLUSIONS

Available studies do not show a consistent clinical superiority of sex-specific hs-cTn 99th percentiles. This may reflect methodological aspects. However, from a pathobiological perspective, the use of sex-specific hs-cTn 99th percentiles makes sense for the ruling in of myocardial infarction. We propose a new approach to hs-cTn 99th cutoffs taking into account the analytical properties of the used assays.

ANMCO/ELAS/SIBioC Consensus Document: biomarkers in heart failure

Biomarkers have dramatically impacted the way heart failure (HF) patients are evaluated and managed. A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biological or pathogenic processes, or pharmacological responses to a therapeutic intervention. Natriuretic peptides [B-type natriuretic peptide (BNP) and N-terminal proBNP] are the gold standard biomarkers in determining the diagnosis and prognosis of HF, and a natriuretic peptide-guided HF management looks promising. In the last few years, an array of additional biomarkers has emerged, each reflecting different pathophysiological processes in the development and progression of HF: myocardial insult, inflammation, fibrosis, and remodelling, but their role in the clinical care of the patient is still partially defined and more studies are needed before to be well validated. Moreover, several new biomarkers have the potential to identify patients with early renal dysfunction and appear to have promise to help the management cardio-renal syndrome. With different biomarkers reflecting HF presence, the various pathways involved in its progression, as well as identifying unique treatment options for HF management, a closer cardiologist-laboratory link, with a multi-biomarker approach to the HF patient, is not far ahead, allowing the unique opportunity for specifically tailoring care to the individual pathological phenotype.

Biomarkers in paediatric heart failure: is there value?

A biomarker is any measurable, surrogate characteristic, which reflects either the presence or the absence of a disease state. This can be a blood test, an imaging characteristic, an exercise parameter, and even a genetic profile. Serum biomarkers are particularly attractive in that their cost to the patient is relatively low in terms of money, time, risk, and ease of obtaining a sample. The potential benefits of a good biomarker are manifold. This manuscript will review serum biomarkers of proposed utility in paediatric heart failure, especially with respect to their ability to aid clinical decision making, diagnosis, and prognosis.

Rationale and design of a randomized, double-blind, event-driven, multicentre study comparing the efficacy and safety of oral rivaroxaban with placebo for reducing the risk of death, myocardial infarction or stroke in subjects with heart failure and significant coronary artery disease following an exacerbation of heart failure: the COMMANDER HF trial

AIMS

Thrombin is a critical element of crosstalk between pathways contributing to worsening of established heart failure (HF). The aim of this study is to explore the efficacy and safety of rivaroxaban 2.5 mg bid compared with placebo (with standard care) after an exacerbation of HF in patients with reduced ejection fraction (HF-rEF) and documented coronary artery disease.

METHODS

This is an international prospective, multicentre, randomized, double-blind, placebo-controlled, event-driven study of approximately 5000 patients for a targeted 984 events. Patients must have a recent symptomatic exacerbation of HF, increased plasma concentrations of natriuretic peptides (B-type natriuretic peptide ≥200 pg/mL or N-terminal pro-B-type natriuretic peptide ≥800 pg/mL), with left ventricular ejection fraction ≤40% and coronary artery disease. Patients requiring anticoagulation for atrial fibrillation or other conditions will be excluded. After an index event (overnight hospitalization, emergency department or observation unit admission, or unscheduled outpatient parenteral treatment for worsening HF), patients will be randomized 1:1 to rivaroxaban or placebo (with standard of care). The primary efficacy outcome event is a composite of all-cause mortality, myocardial infarction or stroke. The principal safety outcome events are the composite of fatal bleeding or bleeding into a critical space with potential permanent disability, bleeding events requiring hospitalization and major bleeding events according to International Society on Thrombosis and Haemostasis bleeding criteria.

CONCLUSION

COMMANDER HF is the first prospective study of a target-specific oral antithrombotic agent in HF. It will provide important information regarding rivaroxaban use following an HF event in an HF-rEF patient population with coronary artery disease.

Prognostic comparison of different sensitivity cardiac troponin assays in stable heart failure

BACKGROUND

Cardiac troponin (cTn) levels offer prognostic information for patients with heart failure. Highly sensitive assays detect levels of cTn much lower than the 99th percentile of standard cTn assays. We hypothesize that cardiac troponin levels measured by a high-sensitivity assay provide better prognostic value compared with cTn levels measured by a standard assay in patients with chronic heart failure.

METHODS

We measured high-sensitivity cTnT (hs-cTnT) and standard cardiac troponin I (cTnI) levels, as well as amino-terminal pro B-type natriuretic peptide (NT-proBNP) in 504 sequential stable patients with a history of heart failure who underwent elective coronary angiography, without acute coronary syndrome, and with 5-year follow-up of all-cause mortality.

RESULTS

The median hs-cTnT level was 21.2 (interquartile range 12.3-40.9) ng/L and 170 subjects died over 5 years. In a head-to-head overall comparison, hs-cTnT provided increased prognostic utility compared with cTnI (area under the curve [AUC] 66.1% and AUC 69.4%, respectively, P = .03; 9.0% integrated discrimination improvement, P < .001; and 13.6% event-specific reclassification, P < .001), and was independent of NT-proBNP and renal function. Even within the subset of patients where cTn levels by both assays were above the limit of quantification, higher hs-cTnT is associated with a 2-fold increase in 5-year mortality risk after adjusting for traditional risk factors (tertile 1 vs 3: hazard ratio [95% confidence interval] 2.0 [1.3-3.2]; P = .0002).

CONCLUSION

Cardiac troponin can be detected by the high-sensitivity assay in more patients with chronic heart failure than the standard assay, and may yield independent and better prognostic accuracy for mortality prediction than standard assay.

The influence of diabetes mellitus on midregional proadrenomedullin concentrations and prognostic value in heart failure outpatients

BACKGROUND

Diabetes mellitus (DM) is associated with an adverse outcome in heart failure (HF). Increased concentrations of midregional proadrenomedullin (MR-proADM) have been associated with DM and are predictors of mortality in HF patients. The aim of this study was to elucidate the impact of DM on MR-proADM concentrations and the prognostic value regarding all-cause mortality and hospitalization among HF patients.

METHODS AND RESULTS

We included 366 patients from an HF clinic; 69 (19%) had a history of DM and 40 (11%) had newly diagnosed DM (HbA1c ≥48 mmol/mol). The median MR-proADM concentration was unaffected by DM status (P = .20) but increased in HF patients with impaired renal function (P < .001). During a median follow-up of 55 months, 189 died, and 292 either died or were hospitalized. After adjustment for clinically relevant parameters, MR-proADM was associated with all-cause mortality (hazard ratio [HR] 1.3, 95% confidence interval [CI] 1.1-1.4; P = .01) and the combined end point of death and hospitalization (HR 1.2, 95% CI 1.1-1.4; P = .02) per 1 SD increment of ln-transformed variable. No interaction between DM and MR-proADM was found regarding mortality or hospitalization.

CONCLUSIONS

Diabetes status had no impact on MR-proADM concentrations or in the predictive ability of MR-proADM in HF patients.

Clinical relevance of biomarkers in heart failure and cardiorenal syndrome: the role of natriuretic peptides and troponin

In recent years, numerous biomarkers have been studied in heart failure to improve diagnostic accuracy and identify patients at higher risk. The overall outcome remains fairish despite improvements in therapy, with mean survival after first hospitalization, around 5 years. We therefore need surrogate end points to better understand the pathogenetic mechanisms of the disease, including interplays with other organs. The kidney plays an important role in the initiation and progression of HF, and around one-third of patients with HF show some degree of renal dysfunction. In addition, treatment for HF often worsens renal function, consequently to hemodynamic and clinical improvement do not correspond an effective improvement in HF prognosis. Association between HF and renal impairment (RI) is now classified as cardiorenal syndrome (CRS) pointing out the bidirectional nature of this vicious circle leading to a mutual and progressive damage of both organs. The clinicians can rely on circulating biomarkers that give insights into the underlying pathogenetic mechanisms and help in risk stratification. Recently, a multimarker strategy including biomarker tool to traditional risk scores has been purposed and applied: Although each biomarker provided incremental outcome benefit, the combination of multiple biomarkers should offer the greatest improvement in risk prediction. Natriuretic peptides (NP) and cardiac troponins (TN) are the two biomarkers most studied in this setting, probably because of their organ-specific nature. However, both NP and TN cutoffs in presence of renal dysfunction need to be revised and discussed in relation to age, gender and stage of RI. In this context, the biomarkers are a unique opportunity to elucidate pathophysiological mechanisms, tailor clinical management to the single patient and improve outcomes. Specific studies about the exact role of biomarkers as in HF as in CRS should be planned and considered for future trials.

High sensitivity troponin T in acute medicine; more questions than answers?

BACKGROUND

Troponin testing in acute medicine is routine. The introduction of a high sensitivity assay (hs Tn T) has created uncertainty regarding the clinical significance of 'abnormal' troponin T levels. The previous assay could not detect troponin levels <30 ng/l.

AIMS AND METHODS

To characterize those with a hs Tn T ≥14 ng/l. Prospective cohort study of consecutive admissions to an acute medical unit.

RESULTS

Troponin was measured in 564 consecutive patients (∼50% of all admissions) over 1 month; was ≥14 ng/l in 224 (40%) of which 220 patients had demographic data for this analysis. Median (inter-quartile range) peak troponin was 47.5 ng/l (24-130) and 36% had a Tn T between 14 and 30 ng/l. Mean [standard deviation (SD)] age was 72 (12) years and 57% were male. Only 44 patients (20%) had an acute myocardial infarction, reflecting the increased sensitivity but reduced specificity of the assay. Prognosis was poor with 31% mortality at 1 year. Over a mean (SD) follow-up of 648 (61) days, there were 87 deaths (40%). Those with a primary non-cardiac diagnosis (n = 126) had poorer survival than those with a primary cardiac diagnosis (n = 94). Troponin elevation related to sepsis conferred a very poor prognosis with 24 deaths (70%) over the follow-up period.

CONCLUSION

Elevated hs Tn T is very common in acute medicine, but myocardial infarction as an explanation is uncommon. Overall, the prognosis is poor with a tendency to worse outcomes in those with a primary 'non-cardiac' diagnosis.

Biomarkers in ACS and Heart Failure: Should Men and Women Be Interpreted Differently?

BACKGROUND

Sex-based differences exist in the circulating concentrations of certain novel and established biomarkers in patients with acute coronary syndromes (ACS) and heart failure (HF). However, to date, few studies have compared the diagnostic and prognostic utility of these markers in men vs women.

CONTENT

This mini-review contains a discussion of the published reports of studies that have explored whether differences in biomarker concentrations exist between men and women with ACS or HF. It also examines those studies that have compared the utility of biomarkers for diagnosis or risk stratification in women vs men. Because biomarkers are often used to make therapeutic and triage decisions in patient care, the potential clinical implications for any observed differences in biomarker reference limits for men and women is discussed.

SUMMARY

Although the concentration distributions may differ between men and women for certain biomarkers in clinical use, the clinical implications of these observations remain unclear. Because elements of the pathophysiology of ACS and HF may differ between the sexes, further research is needed to better evaluate the diagnostic and prognostic utility of biomarkers in men vs women.

Predictors of high sensitivity cardiac troponin T in chronic kidney disease patients: a cross-sectional study in the chronic renal insufficiency cohort (CRIC)

Background

Cardiac troponin T is independently associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). Serum levels of high sensitivity cardiac troponin T (hs-TnT) reflect subclinical myocardial injury in ambulatory patients. We sought to determine the distribution and predictors of hs-TnT in CKD patients without overt cardiovascular disease (CVD).

Methods

We studied 2464 participants within the multi-ethnic Chronic Renal Insufficiency Cohort (CRIC) who did not have self-reported CVD. We considered renal and non-renal factors as potential determinants of hs-TnT, including demographics, comorbidities, left ventricular (LV) mass, serologic factors, estimated glomerular filtration rate (eGFR) and albumin to creatinine ratio.

Results

Hs-TnT was detectable in 81% of subjects, and the median (IQR) hs-TnT was 9.4 pg/ml (4.3-18.3). Analysis was performed using Tobit regression, adjusting for renal and non-renal factors. After adjustment, lower eGFR was associated with higher expected hs-TnT; participants with eGFR < 30 ml/min/1.73 m² had 3-fold higher expected hs-TnT compared to subjects with eGFR > 60. Older age, male gender, black race, LV mass, diabetes and higher blood pressure all had strong, independent associations with higher expected hs-TnT.

Conclusions

Knowledge of the determinants of hs-TnT in this cohort may guide further research on the pathology of heart disease in patients with CKD and help to stratify sub-groups of CKD patients at higher cardiovascular risk.

Incremental prognostic power of novel biomarkers (growth-differentiation factor-15, high-sensitivity C-reactive protein, galectin-3, and high-sensitivity troponin-T) in patients with advanced chronic heart failure

Elevated natriuretic peptides provide strong prognostic information in patients with heart failure (HF). The role of novel biomarkers in HF needs to be established. Our objective was to evaluate the prognostic power of novel biomarkers, incremental to the N-terminal portion of the natriuretic peptide (NT-proBNP) in chronic HF. Concentrations of circulating NT-proBNP, growth differentiation factor 15 (GDF-15), high-sensitivity C-reactive protein (hs-CRP), galectin-3 (Gal-3), and high-sensitivity troponin T (hs-TnT) were measured and related to all-cause long-term mortality. Of 209 patients (age 71 ± 10 years, 73% male patients, 97% New York Heart Association class III), 151 (72%) died during a median follow-up of 8.7 ± 1 year. The calculated area under the curve for NT-proBNP was 0.63, GDF-15 0.78, hs-CRP 0.66, Gal-3 0.68, and hs-TnT 0.68 (all p <0.01). Each marker was predictive for mortality in univariate analysis. In multivariate analysis, elevated concentrations of GDF-15 (hazard ratio [HR] 1.41, confidence interval [CI] 1.1 to 178, p = 0.005), hs-CRP (HR 1.38, CI 1.15 to 1.67, p = 0.001), and hs-TnT (HR 1.27, CI 1.06 to 1.53, p = 0.008) were independently related to mortality. All novel markers had an incremental value to NT-proBNP, using the integrated discrimination improvement. In conclusion, in chronic HF, GDF-15, hs-CRP, and hs-TnT are independent prognostic markers, incremental to NT-proBNP, in predicting long-term mortality. In this study, GDF-15 is the most predictive marker, even stronger than NT-proBNP.

Ascertainment of any and all neurologic and myocardial damage in carotid revascularization: the key to optimization?

The majority of carotid revascularization procedures performed at present are in asymptomatic patients. Since such procedures convey no immediate benefit, but rather protect from future hazard, optimization of procedural safety is mandatory. The authors focus their discussion on the methodologies that assess periprocedural myocardial damage and brain injury, as used in past clinical trials, from the fields of perioperative medicine and neurovascular imaging, and discuss methodologies to reduce both events in carotid revascularization.

Impact of insulin resistance on silent and ongoing myocardial damage in normal subjects: the Takahata study

Background. Insulin resistance (IR) is part of the metabolic syndrome (Mets) that develops after lifestyle changes and obesity. Although the association between Mets and myocardial injury is well known, the effect of IR on myocardial damage remains unclear. Methods and Results. We studied 2200 normal subjects who participated in a community-based health check in the town of Takahata in northern Japan. The presence of IR was assessed by homeostasis model assessment ratio, and the serum level of heart-type fatty acid binding protein (H-FABP) was measured as a maker of silent and ongoing myocardial damage. H-FABP levels were significantly higher in subjects with IR and Mets than in those without metabolic disorder regardless of gender. Multivariate logistic analysis showed that the presence of IR was independently associated with latent myocardial damage (odds ratio: 1.574, 95% confidence interval 1.1–2.3) similar to the presence of Mets. Conclusions. In a screening of healthy subjects, IR and Mets were similarly related to higher H-FABP levels, suggesting that there may be an asymptomatic population in the early stages of metabolic disorder that is exposed to myocardial damage and might be susceptible to silent heart failure.