The Cardiac Troponin T and I are highly cardiac specific biochemical markers of myocardial injury. They are very sensitive markers to detect all kinds of myocardial injury, and are able to distinguish myocardial injury and skeletal injury. Furthermore, They are independent predictor of future cardiac events. Such markers are now widely used in the clinic practice. It is prospective to use them in Forensic Medical Science.
Biomarkers ; Forensic Medicine ; Humans ; Myocardial Infarction/blood* ; Myocardium/metabolism* ; Troponin I/blood* ; Troponin T/blood*

The diagnosis and management of patients with acute coronary syndrome (ACS) have evolved dramatically over the past decade. Biomarkers play an important role in the diagnosis of ACS, especially in unstable angina and non-ST-segment elevation myocardial infarction. Among these, cardiac troponin and creatine kinase appear to be the most sensitive and specific markers of myocardial injury. Recent studies have revealed several novel biomarkers. Elevated levels of C-reactive protein and interleukin-6 are strong independent markers of increased mortality among patients with ACS. However, the ideal biomarkers that offer early detection, risk stratification, selection of therapy, monitoring disease progression, and treatment efficacy remain to be elucidated. This review assesses limitations and contemporary needs for biomarkers in the context of diagnosis of ACS. It also discusses the newly developing technologies for novel biomarkers or novel biomarker protein signatures discovery, and importance of point-of-care testing for future management.
Acute Coronary Syndrome ; blood ; pathology ; Biomarkers ; blood ; Creatine Kinase ; blood ; Electrocardiography ; Humans ; Myoglobin ; blood ; Necrosis ; blood ; Oxidative Stress ; Platelet Activation ; Troponin I ; blood ; Troponin T ; blood

OBJECTIVE: To investigate the association of myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) with troponin level and left ventricle (LV) function in patients with ST-segment elevated myocardial infarction (STEMI). MATERIALS AND METHODS: Thirty-five STEMI patients who successfully had undergone reperfusion treatment within 1 week of their infarction were consecutively enrolled. All patients were referred for dynamic CT-MPI. Serial high-sensitivity troponin T (hs-TnT) levels and left ventricular ejection fraction (LVEF) measured by echocardiography were recorded. Twenty-six patients with 427 segments were included for analysis. Various quantitative parameters derived from dynamic CT-MPI were analyzed to determine if there was a correlation between hs-TnT levels and LVEF on admission and again at the 6-month mark. RESULTS: The mean radiation dose for dynamic CT-MPI was 3.2 ± 1.1 mSv. Infarcted territories had significantly lower MBF (30.5 ± 7.4 mL/min/100 mL versus 73.4 ± 8.1 mL/min/100 mL, p < 0.001) and myocardial blood volume (MBV) (2.8 ± 0.9 mL/100 mL versus 4.2 ± 1.1 mL/100 mL, p = 0.044) compared with those of reference territories. MBF showed the best correlation with the level of peak hs-TnT (r = −0.682, p < 0.001), and MBV showed a moderate correlation with the level of peak hs-TnT (r = −0.437, p = 0.026); however, the other parameters did not show any significant correlation with hs-TnT levels. As for the association with LV function, only MBF was significantly correlated with LVEF at the time of admission (r = 0.469, p = 0.016) and at 6 months (r = 0.585, p = 0.001). CONCLUSION: MBF quantified by dynamic CT-MPI is significantly inversely correlated with the level of peak hs-TnT. In addition, patients with lower MBF tended to have impaired LV function at the time of their admission and at 6 months.
Blood Volume ; Echocardiography ; Heart Ventricles ; Humans ; Infarction ; Myocardial Infarction ; Myocardial Perfusion Imaging ; Reperfusion ; Stroke Volume ; Troponin T ; Troponin

OBJECTIVETo analyze the sources and distribution decision limits on reference values of myocardial injury markers based on the feedback results of 150 laboratories which participated the 2012 external quality assessment (EQA) programs in China.

METHODSDecision limits on myocardial injury markers from EQA programs were analyzed. Data from maternal and child care service center, children's hospital and corporations were excluded. Abnormal values and errors were eliminated. Mean, median, maximum value, minimum value, P2.5 and P97.5 were calculated. Sources of decision limits were summarized and data were filtered and only values obtained according to the reagent manufacturer's instructions as a reference source were used and grouped based on reagent characteristics.

RESULTSAccording to the surveys on reference interval sources, most of reference sources were derived from reagent manufacturer's instructions and the ratio of each item was: CK-MB (µg/L) 91.30%, Mb (µg/L) 88.44%, cTn-I (µg/L) 86.29%, cTn-T (µg/L) 92.00%, CK-MB (U/L) 70.65%. According to the surveys, the mean and median values of each test parameter were close to each other (CK-MB:3.74, 4.94 µg/L;Mb:76.09, 72.00 µg/L; CTn-I:0.06,0.09 µg/L;cTn-T:0.01, 0.02 µg/L;CK-MB:23.00, 25.00 U/L) . There were significant variations on P2.5 and P97.5 distribution ranges: CK-MB 2.48-7.09 µg/L, Mb 46.00-140.03 µg/L, cTn-I 0.01-1.68 µg/L, cTn-T 0.01-12.61 µg/L, CK-MB 6.00-30.60 U/L. According to the surveys on using various reagents, there were also significant variations on P2.5 and P97.5 reagent distributions.

CONCLUSIONSThe decision limit of the mean and median for each test item is close to each other while the P2.5 and P97.5 distribution of each test item consistency is poor. There is therefore an urgent need to establish an uniform reference values for cardiac markers in China.

Biomarkers ; blood ; China ; Creatine Kinase, MB Form ; blood ; Humans ; Laboratories, Hospital ; Myoglobin ; blood ; Reference Values ; Troponin I ; blood ; Troponin T ; blood

BACKGROUNDN-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) are excellent biomarkers for detecting heart failure and subclinical myocardial injury. However, it remains unclear whether subclinical myocardial injury is associated with NT-proBNP elevation in a community based population.

METHODSIn a community based study, levels of hs-cTnT and of NT-proBNP were determined in 1 497 participants older than 45 years. The lower detection limit of the hs-cTnT assay used in the present study was 0.003 ng/ml. The association of hs-cTnT levels and NT-proBNP levels was analyzed.

RESULTSWhen the subjects with undetectable (<0.003 ng/ml), intermediate (0.003-0.014 ng/ml), and elevated (≥0.014 ng/ml) levels of hs-cTnT were compared (r = 0.175, P < 0.001), a strong association between the hs-cTnT levels and NT-proBNP levels was observed (β = -0.206, P < 0.001; β = -0.118, P < 0.001, respectively). In multivariable analyses, older age and hs-cTnT were positively and independently associated with NT-proBNP levels (β = 0.341, P < 0.001; β = 0.143, P < 0.001, respectively), and male gender and the levels of eGFR were inversely and independently associated with NT-proBNP levels. When the subjects with normal or elevated NT-proBNP were analyzed separately, the hs-cTnT level was not an independent predictor for the NT-proBNP level in the normal NT-proBNP group, whereas the hs-cTnT level was the only independent predictor for NT-proBNP level in the elevated NT-proBNP group (β = 0.399, P < 0.01).

CONCLUSIONSIn this community based population, NT-proBNP elevation was common. In addition to female gender and older age, subclinical myocardial injury indicated by the hs-cTnT level was another important factor in NT-proBNP elevation.

Biomarkers ; analysis ; Female ; Humans ; Male ; Middle Aged ; Natriuretic Peptide, Brain ; blood ; Peptide Fragments ; blood ; Troponin T ; blood

OBJECTIVETo observe the influence of aminoguanidine on cardiac troponin (cTnI) and nitric oxide (NO) levels in serum and myocardium in severely scalded rats.

METHODSSeventy-two Wistar rats were subjected to 30% TBSA full-thickness scald and randomly divided into scald group(S) and aminoguanidine group (A, with intraperitoneal injection of 40 mg/kg aminoguanidine before scald). The venous blood and myocardial tissue of the rats were harvested for the determination of the level of cTnI and nitrite in both serum and myocardium before scald and at 1, 3, 6, 12 and 24 post-burn hours(PBH). Six sham scalded rats served as control group. The changes in the cTnI level and myocardial function were determined among control group, A and S groups at 6PBH.

RESULTSThe serum level of NO in S group [(59.6 +/- 5.4) micromol/L] was obviously higher than that before scald [(24.6 +/- 0.8) micromol/L, P < 0.01], and it peaked at 6 PBH, then decreased obviously at 24 PBH, which was still markedly higher than that in A group (P < 0.01). The changes in NO level in myocardium were similar to the above tendency. Compared with S group, the level of cTnI was significantly increased in A group at each time-point. Compared with A group at 6 PBH, the inhibition of the cardiac function was relatively reduced in S group at 6 PBH.

CONCLUSIONInhibition of NO synthesis by aminoguanidine aggravates cardiac damage and impairment of cardiac function of scalded rats, indicating that NO exerts protective effect on myocardium at early stage after a scald injury.

Animals ; Burns ; metabolism ; Disease Models, Animal ; Myocardium ; metabolism ; Nitric Oxide ; blood ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Troponin T ; blood

OBJECTIVETo determine whether the level of serum cardiac troponin T (cTnT) was increased in patients with congestive heart failure (CHF).

METHODSThis study consisted of 265 patients with CHF and 75 healthy people. Serum cTnT was measured by electrochemiluminescence immunoassay using an Elecsys 1010 automatic analyzer.

RESULTScTnT concentration was 0.181 +/- 0.536 ng/mL in CHF patients and 0.003 +/- 0.001 ng/mL in controls (P < 0.001). Patients were categorized according to the levels of heart function and left ventricular ejection fraction (LVEF). In the first group consisting of 105 patients with LVEF 35%, cTnT was 0.07 +/- 0.0 5 ng/mL (P < 0.01). In patients with NYHA class I, II, III and IV, cTnT values were 0.062 +/- 0.022 ng/mL, 0.113 +/- 0.121 mg/mL, 0.191 +/- 0.231 mg/ml and 0.384 +/- 0.211 mg/mL, respectively (class I vs class II P > 0.05, class II vs class III P < 0.01, class III vs class IV P < 0.01). A negative correlation was observed between serum cTnT concentration and LVEF in 265 patients with CHF (r = -0.493, P < 0.001).

CONCLUSIONSThis study shows that the level of serum cTnT is increased in patients with CHF and that the increased level indicates the severity of CHF.

Adult ; Aged ; Female ; Heart Failure ; blood ; physiopathology ; Humans ; Male ; Middle Aged ; Stroke Volume ; Troponin T ; blood ; Ventricular Function, Left

OBJECTIVETo investigate the influence of the changes in the levels of calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY) on cardiac function of severe burn patients during shock stage.

METHODSSixty severe burn patients with total burn surface area larger than 30% were enrolled as experiment group (E group) , and they received fluid resuscitation and debridement during shock stage. Sixty healthy volunteers were enrolled as control group (C group). The changes in the plasma level of CGRP, NPY and cTnT in E and C groups were observed at 1, 3, 6, 12, 24, 48 post-burn hours (PBH). The correlation among the CGRP, NPY and cTnT in the C group were analyzed.

RESULTSAt 3 PBH, the plasma level of CGRP in E group (28 +/- 6) ng/L was lower than that in C group (55 +/- 7) ng/L , and it reached the lowest level at 12 PBH (15 +/- 4)ng/L . It was still lower than that in C group at 48 PBH (P < 0.05). The levels of NPY and cTnT in E group were significantly increased at 1PBH [(136 +/- 20) ng/L, (0.41 +/- 0.08) microg/L] compared with that in C group[ (86 +/- 13) ng/L, (0.16 +/- 0.06) microg/L], peaking at 12PBH [(189 +/- 31) ng/L, (1.78 +/- 0. 47) microg/L], and remaining higher than those in C group at 48PBH. There exhibited obvious negative correlation between the changes in the level of CGRP and cTnT ( r = -0.76, P < 0.01), while obvious positive correlation was found between the changes in level of NPY and cTnT ( r = 0.79, P < 0.01).

CONCLUSIONThe decrease in CGRP level and the increase in NPY level might play important roles in myocardial injury during shock stage of severe burn patients.

Adult ; Burns ; blood ; physiopathology ; Calcitonin Gene-Related Peptide ; blood ; Female ; Humans ; Male ; Middle Aged ; Myocardium ; metabolism ; Neuropeptide Y ; blood ; Shock, Traumatic ; blood ; physiopathology ; Troponin T ; blood

OBJECTIVETo investigate the changes of cardiac T troponin (cTnT) and high-sensitivity C reactive protein (hs-CRP) in children with viral myocarditis (VMC).

METHODSForty children with VMC were examined for cTnT, hs-CRP, and creatine kinase MB (CK-MB) levels.

RESULTSChildren with VMC had significantly higher cTnT, hs-CRP and CK-MB levels than the control group on admission (P<0.01), but obviously decreased after two weeks of treatment. The positivity rate of cTnT and hs-CRP were significantly higher in children with VMC than the control group on admission, and decreased significantly after treatment (P<0.01). The positivity rate of cTnT and hs-CRP were significantly higher than that of CK-MB (P<0.05).

CONCLUSIONSerum cTnT and hs-CRP are sensitive indices for diagnosis of VMC, and their detection have important value in estimation of the patients' condition.

Biomarkers ; blood ; C-Reactive Protein ; metabolism ; Child ; Child, Preschool ; Creatine Kinase, MB Form ; blood ; Female ; Humans ; Male ; Myocarditis ; blood ; virology ; Troponin T ; blood ; Virus Diseases ; blood

BACKGROUND AND OBJECTIVES: The purpose of the study was to evaluate the clinical effect of Nicorandil during percutaneous coronary intervention (PCI) in patients with unstable angina (UA). SUBJECTS AND METHODS: Two hundred patients (61+/-10 years, male 143) with UA were randomly assigned to two groups: intravenous Isosorbide dinitrate (Group I, n=100) and intravenous Nicorandil (Group II, n=100). PCI was performed 12-48 hours after infusion of the agents. The post-procedural cardiac enzymes, 6-month MACE (major adverse cardiac event) and left ventricular ejection fraction (LVEF) were compared between the two groups. RESULTS: Successful PCI was performed in 96 patients (Group I=54, Group II=42). Patients requiring either emergent coronary angiography, temporary pacemaker or platelet glycoprotein IIb/IIIa receptor blocker were excluded. No significant differences were observed between the two groups in terms of the clinical and coronary angiographic characteristics. The level of creatine kinase-MB was elevated in 9 (17%) and 6 patients (14%), troponin T in 16 (30%) and 6 (14%) and troponin I in 25 (46%) and 9 (21%) patients of Groups I and II, respectively, after the PCI. The elevation of all troponins was lower in Group II (28 vs. 10 patients, p=0.01). MACE developed in 9 (17%) and 5 (12%) patients of Groups I and II (p=NS), respectively, during the 6-month clinical follow-up. The LVEF was higher in Group II than in Group I on follow-up echocardiography (65.4+/-7.2% vs. 71.0+/-6.7%, p=0.003). CONCLUSION: Nicorandil may have a myocardial protective effect during PCI in patients with UA.
Angina, Unstable* ; Angioplasty ; Blood Platelets ; Coronary Angiography ; Creatine ; Echocardiography ; Follow-Up Studies ; Glycoproteins ; Humans ; Isosorbide Dinitrate ; Male ; Nicorandil* ; Nitroglycerin ; Percutaneous Coronary Intervention* ; Stroke Volume ; Troponin ; Troponin I ; Troponin T