Logo: to the web site of Uppsala University

Background Emerging evidence suggests that the ratio between cardiac troponin (cTn) I and T may provide information on the risk of adverse outcomes in individuals with cardiovascular disease. Whether the cTn I/T ratio provides prognostic insights in the general population is unknown. Methods The cTn I/T ratio was calculated in 8855 participants (43% female, median age 56 years) from the Generation Scotland Study where both cTnI and cTnT concentrations were above the limit of blank. Multivariable cause-specific Cox proportional hazard models were used to estimate the associations between cTn I/T ratio and the primary outcome of cardiovascular or non-cardiovascular death. Results The median cTn I/T ratio was 0.5 (25th-75th percentile, 0.3-0.8) and median follow-up was 11.4 (10.8-12.7) years. Individuals in the highest ratio tertile (>= 0.64) were more likely to be male, have a higher body mass index and systolic blood pressure, and a history of cardiovascular disease. Those in the lowest ratio tertile (<0.38) were more likely to be smokers or have diabetes. After adjustment for cardiovascular risk factors, the cTn I/T ratio was positively associated with cardiovascular death (per doubling increase, adjusted hazard ratio [HR] 1.16 [95% CI, 1.05-1.28]), while an inverse association was observed for non-cardiovascular death (HR 0.89 [95% CI, 0.81-0.99]). Conclusions The cTn I/T ratio is positively associated with cardiovascular death in the general population, while inversely associated with non-cardiovascular death. Future research is needed to unravel underlying mechanisms and determine whether the cTn I/T ratio provides valuable information regarding risk of cardiovascular and non-cardiovascular mortality to guide further management.

BACKGROUND

The extent to which high-sensitivity cardiac troponin can predict cardiovascular disease (CVD) is uncertain.

OBJECTIVES We aimed to quantify the potential advantage of adding information on cardiac troponins to conventional risk factors in the prevention of CVD. METHODS We meta-analyzed individual-participant data from 15 cohorts, comprising 62,150 participants without prior CVD. We calculated HRs, measures of risk discrimination, and reclassification after adding cardiac troponin T (cTnT) or I (cTnI) to conventional risk factors. The primary outcome was first-onset CVD (ie, coronary heart disease or stroke). We then modeled the implications of initiating statin therapy using incidence rates from 2.1 million individuals from the United Kingdom.

RESULTS

Among participants with cTnT or cTnI measurements, 8,133 and 3,749 incident CVD events occurred during a median follow-up of 11.8 and 9.8 years, respectively. HRs for CVD per 1-SD higher concentration were 1.31 (95% CI: 1.25-1.37) for cTnT and 1.26(95% CI: 1.19-1.33) for cTnI. Addition of cTnT or cTnI to conventional risk factors was associated with C-index increases of 0.015 (95% CI: 0.012-0.018) and 0.012 (95% CI: 0.0090.015) and continuous net reclassification improvements of 6% and 5% in cases and 22% and 17% in noncases. One additional CVD event would be prevented for every 408 and 473 individuals screened based on statin therapy in those whose CVD risk is reclassified from intermediate to high risk after cTnT or cTnI measurement, respectively.

CONCLUSIONS Measurement of cardiac troponin results in a modest improvement in the prediction of first-onset CVD that may translate into population health benefits if used at scale.

The 99th percentile of cardiac troponin assays for determining the presence of acute myocardial infarction (AMI) was set when assay analytical performance was much less precise than currently and was chosen, in part, to reduce the frequency of 'false-positive' results. A result greater than 99th percentile criterion has been a requirement of each version of the universal definition of MI. It also became used as a dichotomous decision-making threshold in diagnostic strategies for investigating AMI in acute care settings. There are numerous difficulties in deriving the 99th percentile which undermine its reliability as a standalone test threshold. It is important for patient safety that all users are aware of the challenges and pitfalls of using the 99th percentile for decision-making. We present a focused review of the 99th percentile, highlighting some difficulties with its use as a decision threshold as well as possible adjunctive strategies and alternative approaches.

Aims Cardiac troponin plays an essential role in the management of non-ST segment elevation acute coronary syndrome (NSTE-ACS). However, it is not clear whether troponin concentrations provide guidance regarding the initiation of prognostically beneficial cardiovascular medications [i.e. betablockers, renin-angiotensin-aldosterone system (RAAS) inhibitors, and statins] in NSTE-ACS. Methods and results Registry-based study investigating three NSTE-ACS cohorts (n = 43 075, 40 162, and 46 698) with elevated high-sensitivity cardiac troponin concentrations >14 ng/L. Cox proportional regression models with the addition of interaction terms were used to analyse the interrelations of high-sensitivity cardiac troponin T (hs-cTnT) concentrations, new initiated medications with the respective three drug classes, and long-term risk of all-cause mortality and major adverse events (MAE). Betablockers were associated with risk reductions of 8 and 5% regarding all-cause mortality and MAE, respectively. There was no evidence of an interaction with hs-cTnT concentrations. RAAS inhibitors were associated with 13 and 8% risk reductions, respectively, with a weak interaction between hs-cTnT and MAE (Pinteraction = 0.016). However, no increasing prognostic benefit was noted at hs-cTnT concentrations >100 ng/L. Statins were associated with 38 and 32% risk reductions, respectively, with prognostic benefit across the entire range of hs-cTnT concentrations, and with a weak interaction regarding MAE (Pinteraction = 0.011). Conclusion Cardiovascular medications provide different prognostic benefit in patients with NSTE-ACS with elevated hs-cTnT, and there was some evidence of greater treatment effects regarding MAE along with higher hs-cTnT concentrations. However, hs-cTnT appears only to have limited value overall for customizing such treatments.

Importance Identification of individuals at high risk for atherosclerotic cardiovascular disease within the population is important to inform primary prevention strategies. Objective To evaluate the prognostic value of routinely available cardiovascular biomarkers when added to established risk factors. Design, Setting, and Participants Individual-level analysis including data on cardiovascular biomarkers from 28 general population-based cohorts from 12 countries and 4 continents with assessments by participant age. The median follow-up was 11.8 years. Exposure Measurement of high-sensitivity cardiac troponin I, high-sensitivity cardiac troponin T, N-terminal pro-B-type natriuretic peptide, B-type natriuretic peptide, or high-sensitivity C-reactive protein. Main Outcomes and Measures The primary outcome was incident atherosclerotic cardiovascular disease, which included all fatal and nonfatal events. The secondary outcomes were all-cause mortality, heart failure, ischemic stroke, and myocardial infarction. Subdistribution hazard ratios (HRs) for the association of biomarkers and outcomes were calculated after adjustment for established risk factors. The additional predictive value of the biomarkers was assessed using the C statistic and reclassification analyses. Results The analyses included 164 054 individuals (median age, 53.1 years [IQR, 42.7-62.9 years] and 52.4% were women). There were 17 211 incident atherosclerotic cardiovascular disease events. All biomarkers were significantly associated with incident atherosclerotic cardiovascular disease (subdistribution HR per 1-SD change, 1.13 [95% CI, 1.11-1.16] for high-sensitivity cardiac troponin I; 1.18 [95% CI, 1.12-1.23] for high-sensitivity cardiac troponin T; 1.21 [95% CI, 1.18-1.24] for N-terminal pro-B-type natriuretic peptide; 1.14 [95% CI, 1.08-1.22] for B-type natriuretic peptide; and 1.14 [95% CI, 1.12-1.16] for high-sensitivity C-reactive protein) and all secondary outcomes. The addition of each single biomarker to a model that included established risk factors improved the C statistic. For 10-year incident atherosclerotic cardiovascular disease in younger people (aged <65 years), the combination of high-sensitivity cardiac troponin I, N-terminal pro-B-type natriuretic peptide, and high-sensitivity C-reactive protein resulted in a C statistic improvement from 0.812 (95% CI, 0.8021-0.8208) to 0.8194 (95% CI, 0.8089-0.8277). The combination of these biomarkers also improved reclassification compared with the conventional model. Improvements in risk prediction were most pronounced for the secondary outcomes of heart failure and all-cause mortality. The incremental value of biomarkers was greater in people aged 65 years or older vs younger people. Conclusions and Relevance Cardiovascular biomarkers were strongly associated with fatal and nonfatal cardiovascular events and mortality. The addition of biomarkers to established risk factors led to only a small improvement in risk prediction metrics for atherosclerotic cardiovascular disease, but was more favorable for heart failure and mortality.

Objectives: Biomarker concentrations and their changes during acute coronary syndrome (ACS) provide clinically useful information on pathophysiological processes, e.g. myocardial necrosis, hemodynamic stress and inflammation. However, current evidence on temporal biomarker patterns early during ACS is limited, and studies investigating multiple biomarkers are lacking.

Methods: We measured concentrations of high-sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI), NT-terminal pro-B-type natriuretic peptide, C-reactive protein, and growth-differentiation factor-15 (GDF-15) in plasma samples obtained at randomization in ACS patients from the PLATelet inhibition and patient Outcomes (PLATO) trial. Linear regressions with interaction analyses were used to investigate the associations of biomarker concentrations with the time from symptom onset and to model temporal biomarker concentration patterns.

Results: The study population consisted of 16,944 patients (median age 62 years; 71.3 % males) with 6,853 (40.3 %) having ST-elevation myocardial infarction (STEMI) and 10,141 (59.7 %) having non-ST-elevation ACS (NSTE-ACS). Concentrations of all biomarkers were associated with time from symptom onset (p_interaction<0.001), apart for GDF-15 (p_interaction=0.092). Concentration increases were more pronounced in STEMI compared to NSTE-ACS. Temporal biomarker patterns for hs-cTnT and hs-cTnI were different depending on sex whereas biomarker patterns for the other biomarkers were similar in cohorts defined by age and sex.

Conclusions: Temporal concentration patterns differ for various biomarkers early during ACS, reflecting the variability in the activation and duration of different pathophysiological processes, and the amount of injured myocardium. Our data emphasize that the time elapsed from symptom onset should be considered for the interpretation of biomarker results in ACS.

Background: The pathobiology of myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is often uncertain. Investigating biomarker concentrations and their changes may offer novel pathophysiological insights.

Methods and Results: In this post hoc study of the PLATO (Platelet Inhibition and Patient Outcomes) trial, concentrations of hs‐cTnT (high‐sensitivity cardiac troponin T), NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide), hs‐CRP (high‐sensitivity C‐reactive protein), and GDF‐15 (growth differentiation factor 15) were measured in patients with MINOCA at baseline (n=554) and at 1‐month follow‐up (n=107). For comparisons, biomarkers were also measured in patients with MI with obstructive (stenosis ≥50%) coronary artery disease (baseline: n=11 106; follow‐up: n=2755]). Adjusted linear regression models were used to compare concentrations and their short‐ and long‐term changes. The adjusted geometric mean ratios (GMRs) in patients with MINOCA (median age, 61 years; 50.4% women) indicated lower hs‐cTnT (GMR, 0.77 [95% CI, 0.68–0.88]) but higher hs‐CRP (GMR, 1.21 [95% CI, 1.08–1.37]) and GDF‐15 concentrations (GMR, 1.06 [95% CI, 1.02–1.11]) at baseline compared with patients with MI with obstructive coronary artery disease, whereas NT‐proBNP concentrations were similar. Temporal decreases in hs‐cTnT, NT‐proBNP, and hs‐CRP concentrations until 1‐month follow‐up were more pronounced in patients with MINOCA. At follow‐up, patients with MINOCA had lower concentrations of hs‐cTnT (GMR, 0.71 [95% CI, 0.60–0.84]), NT‐proBNP (GMR, 0.45 [95% CI, 0.36–0.56]), and hs‐CRP (GMR, 0.68 [95% CI, 0.53–0.86]). One‐month GDF‐15 concentrations were similar between both groups with MI.

Conclusions: Biomarker concentrations suggest greater initial inflammatory activity, similar degree of myocardial dysfunction, and less pronounced myocardial injury during the acute phase of MINOCA compared with MI with obstructive coronary artery disease but also faster myocardial recovery.

CLINICAL TRAIL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00391872.

 Objectives

Measurement of high-sensitivity (hs) cardiac troponin (cTn) T and I is widely studied for cardiac assessment of stable populations. Recent data suggest clinical and prognostic discrepancies between both hs-cTn. We aimed at reviewing published studies with respect to underlying causes and clinical implications.

Content

We summarized current evidence on release and clearance mechanisms of cTnT and I, and on preanalytical and assay-related issues potentially portending to differences in measured concentrations. We also performed a systematic review of outcome studies comparing both hs-cTn in the general population, patients with congestive heart failure, stable coronary artery disease and atrial fibrillation.

Summary and outlook

For the interpretation of concentrations of hs-cTnT, stronger association with renal dysfunction compared to hs-cTnI should be considered. Hs-cTnT also appears to be a stronger indicator of general cardiovascular morbidity and all-cause mortality. Hs-cTnI concentrations tend to be more sensitive to coronary artery disease and ischemic outcomes. These findings apparently reflect variations in the mechanisms of cardiac affections resulting in cTn release. Whether these differences are of clinically relevance remains to be elucidated. However, having the option of choosing between either hs-cTn might represent an option for framing individualized cardiac assessment in the future.

Background

The History, Electrocardiogram (ECG), Age, Risk factors and Troponin, (HEART) score is useful for early risk stratification in chest pain patients. The aim was to validate previous findings that a simplified score using history, ECG and troponin (HET-score) has similar ability to stratify risk.

Methods

Patients presenting with chest pain with duration of ≥10 min and an onset of last episode ≤12 h but without ST-segment elevation on ECG at 6 emergency departments were eligible for inclusion. The HEART-score and the simplified HET-score were calculated. The endpoint was a composite of myocardial infarction (MI) as index diagnosis, readmission due to new MI or death within 30 days.

Results

HEART-score identified 32% as low risk (0-2p), 47% as intermediate risk (3-5p), and 20% as high risk (6-10p) patients. The endpoint occurred in 0.5%, 7.3% and 35.7%, respectively. HET-score identified 39%, 42% and 19% as low- (0p), intermediate- (1-2p) and high-risk (3-6p) patients, with the endpoint occurring in 0.6%, 6.2% and 43.2%, respectively.

When all variables included in the HEART-score were included in a multivariable logistic regression analysis, only History (OR, CI [95%]): 2.97(2.16–4.09), ECG (1.61[1.14–2.28]) and troponin level (5.21[3.91–6.95]) were significantly associated with cardiovascular events. When HEART- and HET-score were compared in a ROC-analysis, HET-score had a significantly larger AUC (0.887 vs 0.853, p < 0.001).

Conclusions

Compared with HEART-score, HET-score is simpler and appears to have similar ability to discriminate between chest pain patients with and without cardiovascular event.

Despite poor prognosis, patients with type 2 myocardial infarction (MI) tend to be underdiagnosed and undertreated compared to those with type 1 MI. Whether this discrepancy has improved over time is uncertain. We conducted a registry-based cohort study investigating type 2 MI patients managed at Swedish coronary care units (n = 14,833) during 2010–2022. Multivariable-adjusted changes (first three vs last three calendar years of the observation period) were assessed regarding diagnostic examinations (echocardiography, coronary assessment), provision of cardioprotective medications (betablockers, renin–angiotensin–aldosterone-system inhibitors, statins) and 1-year all-cause mortality. Compared to type 1 MI patients (n = 184,329), those with type 2 MI less often had diagnostic examinations and cardioprotective medications. Increases in the use of echocardiography (OR 1.08 [95% confidence interval 1.06–1.09]) and coronary assessment (OR 1.06 [95% confidence interval 1.04–1.08]) were smaller compared to type 1 MI (p_interaction < 0.001). The provision of medications did not increase in type 2 MI. All-cause mortality rate in type 2 MI was 25.4% without temporal change (OR 1.03 [95% confidence interval 0.98–1.07]). Taken together, the provision of medications and all-cause mortality did ot improve in type 2 MI despite modest increases in diagnostic procedures. This emphasizes the need of defining optimal care pathways in these patients.