Elevated cTnT Levels Research Articles

Early myocardial injury in children on doxorubicin for cancer chemotherapy: a cross-sectional study in a tertiary referral centre in Kenya

IntroductionUse of doxorubicin, an anthracycline chemotherapeutic agent has been associated with late-occurring cardiac toxicities. Detection of early-occurring cardiac effects of cancer chemotherapy is essential to prevent occurrence of adverse events including toxicity, myocardial dysfunction, and death.ObjectiveTo investigate the prevalence of elevated cardiac troponin T (cTnT) and associated factors of myocardial injury in children on doxorubicin cancer chemotherapy.MethodsDesign: A cross-sectional study.Setting and subjects: A hospital-based study conducted on children aged 1-month to 12.4-years who had a diagnosis of cancer and were admitted at Kenyatta National Hospital (KNH).Interventions and outcomes: The patients underwent Echocardiography (ECHO) before their scheduled chemotherapy infusion. Twenty-four (24) hours after the chemotherapy infusion the patients had an evaluation of the serum cardiac troponin T (cTnT) and a repeat ECHO. Myocardial injury was defined as cTnT level > 0.014 ng/ml or a Fractional Shortening (FS) of < 29% on ECHO.ResultsOne hundred (100) children were included in the final analysis. Thirty-two percent (32%) of the study population had an elevated cTnT. A cumulative doxorubicin dose of > 175 mg/m2 was significantly associated with and elevated cTnT (OR, 10.76; 95% CI, 1.18–97.92; p = 0.035). Diagnosis of nephroblastoma was also associated with an elevated cTnT (OR, 3.0; 95% CI, 1.23–7.26) but not statistically significant (p = 0.105). Nine percent (9%) of the participants had echocardiographic evidence of myocardial injury.ConclusionWhen compared to echocardiography, elevated levels of cTnT showed a higher association with early-occurring chemotherapy-induced myocardial injury among children on cancer treatment at a tertiary teaching and referral hospital in Kenya.

Troponin efficacy in the diagnosis of acute coronary syndrome in patients with chronic renal failure.

There is no consensus on whether cardiac troponins with high reliability values should be different diagnostic criteria for acute myocardial infarction in patients with and without renal dysfunction. Although it is often emphasized that the etiology of elevated troponin levels in chronic kidney disease (CKD) remains unclear, elevated cardiac troponin (cTnT) levels have been associated with increased subclinical cardiac damage in these patient groups. In this study, we investigated the value of cTnT value in diagnosing acute coronary syndrome in CKD patients with high clinical suspicion of acute coronary syndrome and without acute ST segment elevation on electrocardiogram. The aim was to prevent cardiac ischemia from being overlooked in CKD patients. Coronary angiography revealed vessel occlusion in 192 patients, and the mortality rate after treatment decisions was 6.7%. The first measured troponin results showed a significant difference in patients who did not survive, indicating the prognostic value of troponin levels. Troponin values were compared with cardiovascular pathologies obtained by angiography, and elevated troponin levels strongly correlated with pathologic angiography results. The conclusion highlighted that despite prognostic uncertainties, biomarkers used for acute myocardial infarction diagnosis in patients with renal insufficiency are reliable in those with renal dysfunction. Elevated cTnT levels in CKD patients are considered a clear marker of cardiac ischemia, emphasizing the need for careful consideration of troponin values in this population.

Aconitum carmichaelii Debx. Attenuates Heart Failure through Inhibiting Inflammation and Abnormal Vascular Remodeling

Heart failure (HF) is the most common complication following myocardial infarction, closely associated with ventricular remodeling. Aconitum carmichaelii Debx., a traditional Chinese herb, possesses therapeutic effects on HF and related cardiac diseases. However, its effects and mechanisms on HF-associated cardiac diseases are still unclear. In the present study, a water extraction of toasted Aconitum carmichaelii Debx. (WETA) was verified using UPLC-Q/TOF-MS. The heart function of HF rats was assessed by echocardiography and strain analysis, and myocardial injury was measured by serum levels of CK-MB, cTnT, and cTnI. The pathological changes of cardiac tissues were evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin and eosin (H&E) staining, and Masson's trichrome staining. Additionally, the levels of inflammation-related genes and proteins and components related to vascular remodeling were detected by RT-qPCR, Western blot, and immunofluorescence. WETA significantly inhibited the changes in echocardiographic parameters and the increase in heart weight, cardiac infarction size, the myonecrosis, edema, and infiltration of inflammatory cells, collagen deposition in heart tissues, and also mitigated the elevated serum levels of CK-MB, cTnT, and cTnI in ISO-induced rats. Additionally, WETA suppressed the expressions of inflammatory genes, including IL-1β, IL-6, and TNF-α and vascular injury-related genes, such as VCAM1, ICAM1, ANP, BNP, and MHC in heart tissues of ISO-induced HF rats, which were further confirmed by Western blotting and immunofluorescence. In summary, the myocardial protective effect of WETA was conferred through inhibiting inflammatory responses and abnormal vascular remodeling in ISO-treated rats.

The role of myocarditis in the acute phase of Kawasaki as a predictor of the future coronary aneurysm: a case–control study

BackgroundThis study aimed to evaluate the relationship between cardiac troponin I and T (cTnI, cTnT) and creatine kinase (CK)-MB during the acute phase of Kawasaki disease (KD) and the development of coronary artery involvement (CAI).ResultsNinety children diagnosed with KD and 38 attending ambulatory clinics as controls were enrolled in this study. Serum levels of cardiac enzymes were measured in all case and control groups. Serial echocardiograms were performed in KD patients during the acute, subacute and convalescence phases. Thirty-six percent of patients had CAI during the acute phase of KD; this rate was 21% and 18% in the echocardiography in the sub-acute and convalescent-phase, respectively. Elevated serum cTnI and cTnT levels were seen in 15.5% and 10% of KD patients, respectively, but not in the controls (P < 0.01). Patients with abnormal echocardiography had significantly higher levels of CK-MB but cTnI and cTnT. Cardiac troponins have high specificity, and CK-MB had a high sensitivity for predicting CAI in KD.ConclusionSubclinical myocarditis occurs during KD, and serum cardiac troponin levels are significantly elevated, but cardiac biomarkers cannot predict CAI in the future.

Possible pathophysiological mechanisms of cardiac troponin level elevations in blood serum and urine in arterial hypertension

The review aimed to discuss and detail the main mechanisms of myocardial cell injury and increased concentrations of cardiac specific troponin isoforms (cTnI and cTnT) in blood serum and urine in hypertension. The search and analysis of foreign and domestic literature were carried out using the MedLine, EMBASE, Scopus and eLibrary databases to achieve this goal. According to recent experimental and clinical researches using high and ultra-sensitive methods for determining cTnI and cTnT, cardiomyocytes are extremely sensitive to many damaging factors in a number of physiological and pathological conditions. The serum concentrations of cTnI and cTnT can increase at the earliest stages of cardiovascular diseases (for example, in prehypertension, latent forms of coronary heart disease, arterial hypertension) and are important for predicting subsequent complications in the form of acute and life-threatening cardiovascular diseases (myocardial infarction, stroke, heart failure, and others). Moreover, troponin molecules can be detected not only in blood serum but also in non-invasively obtained biological fluids, including urine and oral fluid, which in the future can be used as new methods for the non-invasive diagnosis of many cardiovascular diseases. Although elevated levels of cTnI and cTnT in blood serum and urine in hypertension have a fairly high diagnostic and prognostic value, the pathophysiological mechanisms of cardiac troponins level elevations in human biological fluids in this pathological condition remain unclear.

Troponin T Elevation After Percutaneous Left Atrial Appendage Occlusion.

Background: Cardiac troponin T (cTNT) has been widely used in detecting cardiac damage. Elevated cTNT level has been reported to be associated with increased mortality in multiple cardiac conditions. It is not uncommon to observe an increased level of cTNT in patients after left atrial appendage occlusion (LAAO). The objective of the study is to study the incidence, significance, and factors associated with cTNT elevation after LAAO.Methods: We prospectively included patients who underwent LAAO from January 2019 to July 2020 in Fudan Zhongshan Hospital. Patients were divided into those with elevated cTNT after procedure and those with normal postprocedure cTNT. All individuals were followed up for 1 year. The primary outcome is major adverse cardiovascular events, which include myocardial infarction, heart failure, cardiac death, and stroke. The second outcome is periprocedure complication, including chest pain, tachycardia, cardiac tamponade, change of electrocardiograph, and atrial thrombus.Results: A total of 190 patients were enrolled. Of the patients, 85.3% had elevated cTNT after LAAO, while 14.7% of them did not. Exposure time, dosage of contrast, types of devices, shapes, and sizes of LAA could contribute to elevated postprocedure cTNT. We found that patients with a Watchman device were more likely to have elevated postprocedure cTNT than those with a Lambre device (89.2 vs. 76.7%, p = 0.029). LAAO shapes were associated with cTNT levels in patients with a Watchman device, while the diameter of the outer disc and LAA depth mattered for the Lambre device. There was no significant difference in the primary and second outcome between the two groups (p-value: 0.619, 0.674).Conclusion: LAAO was found to be commonly accompanied with cTNT elevation, which might not to be related to the complications and adverse cardiac outcomes within 1 year of follow-up. Moreover, eGFR at baseline, exposure time, dosage of contrast, types of LAAO device, and LAA morphology could contribute to cTNT elevation.

The Main Causes and Mechanisms of Increase in Cardiac Troponin Concentrations Other Than Acute Myocardial Infarction (Part 1): Physical Exertion, Inflammatory Heart Disease, Pulmonary Embolism, Renal Failure, Sepsis

The causes and mechanisms of increased cardiac troponin T and I (cTnT and cTnI) concentrations are numerous and are not limited to acute myocardial infarction (AMI) (ischemic necrosis of cardiac myocytes). Any type of reversible or irreversible cardiomyocyte injury can result in elevated serum cTnT and cTnI levels. Researchers and practitioners involved in the diagnosis and treatment of cardiovascular disease, including AMI, should know the key causes and mechanisms of elevated serum cTnT and cTnI levels. This will allow to reduce or completely avoid diagnostic errors and help to choose the most correct tactics for further patient management. The purpose of this article is to discuss the main causes and mechanisms of increase in cardiac troponins concentrations in frequently occurring physiological (physical exertion, psycho-emotional stress) and pathological conditions (inflammatory heart disease, pulmonary embolism, chronic renal failure and sepsis (systemic inflammatory response)) not related to myocardial infarction.

P3117Usefulness of cardiac magnetic resonance imaging for early detection of subclinical chemotherapy-related cardiac dysfunction in cancer patients

Abstract Background Long-term prognosis of cancer patients has been improved along with the progress in chemotherapies. However, chemotherapy-related cardiac dysfunction (CTRCD) is emerging as a serious adverse effect as it worsens patients' outcome and quality of life. Thus, early detection of subclinical CTRCD is an important emerging issue in the management of cancer patients. Cardiac magnetic resonance (CMR) utilizes parametric mapping approach and strain analysis to provide detailed information about cardiac tissue and diastolic cardiac function. Purpose We examined whether the novel CMR imaging techniques are useful for early detection of CTRCD. Methods and results We performed both retrospective and prospective studies. (1) Retrospective study: We retrospectively enrolled 52 cancer patients (mean age 55.6±13 yrs., M/F=14/38) who had been treated with anthracyclines. We examined the usefulness of CMR for quantitative assessment of myocardial fibrosis caused by chemotherapies. We found that native T1 value was significantly prolonged in cancer patients compared with healthy controls (N=10) (1,279±56 vs. 1,240±34 msec, P=0.036). (2) Prospective study: A total of 99 consecutive female patients with breast cancer treated with chemotherapies were enrolled in this study from August 2017 to January 2019. To evaluate CTRCD in those patients, we performed CMR (at baseline and/or 6 months) and biomarkers analysis for cardiac troponin T (cTnT) and BNP at baseline and every 3 months during chemotherapies. In the 99 patients, 52 (mean age 53.0±12.7 yrs.) completed cardiac assessment at 6 months, and 6 (12%) developed CTRCD defined as a reduction in left ventricular ejection fraction (LVEF) &gt;10% from baseline and below 53% without symptoms. In patients with CTRCD (CTRCD group, N=6), as compared with those without it (non-CTRCD group, N=46), native T1 value was significantly prolonged after chemotherapies (1,303±32 vs. 1,322±22 msec at 6 months, P=0.03). Plasma cTnT levels at 3 months were also significantly higher in the CTRCD group compared with the non-CTRCD group [0.022 (IQR 0.015–0.026) vs. 0.01 (0.006–0.014) ng/mL, P=0.024], whereas there was no difference in BNP values. In the 52 patients, 28 (mean age 56.3±12.3 yrs.) underwent CMR both before and 6 months after chemotherapies. In those patients, LVEF and global radial strain were significantly decreased at 6 months from baseline (LVEF, from 70.5±4.6 to 66.0±7.1%; global radial strain, from 70.0±22.5 to 61.1±22.6%, respectively, both P&lt;0.05). In patients with elevated cTnT levels at 3 months, as compared with those without it, LVEF and extracellular volume fraction (ECV) at 6 months were significantly worse (LVEF, 59.0±6.0 vs. 62.7±2.6%, P=0.042; ECV, 32.3±2.9 vs. 30.2±2.3%, P=0.049, respectively). Conclusions These results indicate that novel CMR imaging techniques are useful for early detection of CTRCD among cancer patients treated with chemotherapies.

P.272Cardiac troponin T (cTnT) as a highly sensitive parameter for spinal muscular atrophy (SMA) in a floppy infant

Studies with new therapeutics for SMA patients showed the best outcome when treatment was started pre-symptomatic. Thus, early detection, e.g. via genetic newborn screenings, is required. Pilot projects have already been implemented in a few countries. High costs and lack of availability of genetic testing in certain regions are challenging early access to treatment and require other screening methods. Studies in adults with neuromuscular diseases have shown elevated cTnT levels without cardiomyopathy. We evaluated whether increased cTnT is detectable in SMA patients and if it correlates with disease severity. Since 03/2016 we followed 24 patients with SMA. Serum samples were obtained as part of the routine work-up before initiation of treatment. The high sensitivity cTnT-Test by Roche Cobas was used. Cardiac disease was excluded clinically, by echocardiography and by measuring Troponin I (cTnI). Disease severity was determined by SMA type and in SMA1 patients by the need for ventilation within two months after treatment initiation. All cTnI levels were normal. cTnT was 3-10-fold above the upper limit of normal (14ng/L) in infants with SMA1 (80±39). Values of non-ventilated patients were lower than in ventilated patients (p=0,06). cTnT was significantly higher in SMA1 than in SMA2/3 patients (p=0,0002). Our data show that cTnT is elevated in all patients with SMA1 and might be useful as a highly sensitive parameter for SMA in floppy infants. Due to the lack of a control group, specificity can't be determined. Further studies with an increased number of patients evaluating the course of cTnT, including all types of SMA, are required to determine the value of this observation.

Heart rate variability, the dynamic nature of the retinal microvasculature and cardiac stress: providing insight into the brain-retina-heart link: the SABPA study.

Decreased heart-rate-variability (HRV) indicates increased sympathetic nervous system (SNS) activity and modulation with a shift in the sympatho-vagal balance towards SNS predominance. Increased SNS activity may precede volume-loading hypertension, contribute to increases in cardiac troponin T (cTnT), endothelial dysfunction and small vessel disease. Therefore, we investigated the retinal vasculature, HRV during flicker-light-induced-provocation (FLIP) and systemic cTnT, a marker of cardiac stress, to provide further evidence in support of the brain-retina-heart link. Cross-sectional observations were obtained from a bi-ethnic cohort (N = 264), aged 23-68 years. Fasting serum samples for cTnT were obtained. Retinal vascular calibres were quantified from mydriatic eye fundus images and dynamic retinal vessel calibre responses were determined during FLIP. Time-and frequency domain parameters of HRV were calculated during FLIP for each participant. Africans had wider venules and attenuated time domain parameters during FLIP. In Africans, inverse associations emerged between arteriolar dilation and both cTnT and root-mean squared of the standard deviations of successive RR-intervals (rMSSD) (p = 0.030), and between arteriolar constriction and both low-frequency expressed in normalised units (LFnu) (p = 0.003) and high-frequency expressed in normalised units (p = 0.021). Wider venules inversely associated with standard deviation of the NN intervals (SDNN) as well as LFnu (p = 0.009) in Africans. An opposite profile was observed in Caucasians with both time-and frequency domain parameters of HRV in relation to retinal vessel structure and function. FLIP elicited increased SNS activity and modulation in this bi-ethnic cohort. In Africans, decreased HRV during FLIP accompanied arteriolar and venular responses and elevated systemic levels of cTnT, implying that the SNS exerted a significant effect on the smooth muscle tone of the retinal vasculature. Disrupted retinal autoregulation may imply general autonomic nervous system dysfunction; exemplifying central control by the brain on all systemic regulatory functions, across different vascular beds.

Cardiac Biomarker Release After Exercise in Healthy Children and Adolescents: A Systematic Review and Meta-Analysis.

The authors evaluated the impact of acute exercise and 24-hour recovery on serum concentration of cardiac troponins T and I (cTnT and cTnI) and N-terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP) in healthy children and adolescents. The authors also determined the proportion of participants exceeding the upper reference limits and acute myocardial infarction cutoff for each assay. Web of Science, SPORTDiscus, MEDLINE, ScienceDirect, and Scopus databases were systematically searched up to November 2017. Studies were screened and quality-assessed; the data was systematically extracted and analyzed. From 751 studies initially identified, 14 met the inclusion criteria for data extraction. All 3 biomarkers were increased significantly after exercise. A decrease from postexercise to 24 hours was noted in cTnT and cTnI, although this decrease was only statistically significant for cTnT. The upper reference limit was exceeded by 76% of participants for cTnT, a 51% for cTnI, and a 13% for NT-proBNP. Furthermore, the cutoff value for acute myocardial infarction was exceeded by 39% for cTnT and a 11% for cTnI. Postexercise peak values of cTnT were associated with duration and intensity (Q(3) = 28.3, P < .001) while NT-proBNP peak values were associated with duration (Q(2) = 11.9, P = .003). Exercise results in the appearance of elevated levels of cTnT, cTnI, and NT-proBNP in children and adolescents. Postexercise elevations of cTnT and NT-proBNP are associated with exercise duration and intensity.

Cardiac Troponin-T as a Marker of Myocardial Dysfunction in Term Neonates with Perinatal Asphyxia.

To describe the diagnostic test properties of Cardiac Troponin-T (cTnT) in predicting myocardial dysfunction in asphyxiated term neonates by taking echocardiography as the gold standard and to establish the optimum cut-off values of cTnT for myocardial dysfunction, shock, severe hypoxic ischemic encephalopathy (HIE) and mortality by receiver operator characteristic (ROC) curve analysis. This was a prospective study based on diagnostic test evaluation. The study included 120 term asphyxiated neonates in a tertiary care neonatal intensive care unit (NICU) in Southern India from June 2011 through June 2015. All the neonates were clinically evaluated. Venous blood was taken at 4 h of life for cTnT estimation. Echocardiography was done within 24 h of birth. The mean cTnT level of asphyxiated term neonates was 0.207±0.289ng/ml (mean ± SD). Asphyxiated neonates with myocardial dysfunction had higher cTnT levels (0.277±0.231) as compared to those without myocardial dysfunction (0.061±0.036, p = 0.0001). Using ROC curve, the cut-off cTnT values for myocardial dysfunction was 0.1145ng/ml with sensitivity 92.4% and specificity 94.1%. Cardiac Troponin-T levels were significantly higher among asphyxiated neonates with shock (0.378±0.348, p = 0.0001) and the levels also correlated positively with increasing grades of HIE. The cut-off cTnT value for mortality was 0.2505ng/ml with sensitivity 83.9% and specificity 96.6%. In asphyxiated term neonates, early cTnT elevation is a marker for predicting myocardial dysfunction and elevated cTnT levels had high sensitivity and specificity. There was significant relation with increasing cTnT values and increasing grades of HIE.

Cardiac troponin for predicting all-cause mortality in patients with acute ischemic stroke: a meta-analysis.

Cardiac troponins are specific biomarkers of cardiac injury. However, the prognostic usefulness of cardiac troponin in patients with acute ischemic stroke is still controversial. The objective of this meta-analysis was to investigate the association of cardiac troponin elevation with all-cause mortality in patients with acute ischemic stroke. PubMed and Embase databases were searched for relevant studies up to April 31, 2017. All observational studies reporting an association of baseline cardiac troponin-T (cTnT) or troponin-I (cTnI) elevation with all-cause mortality risk in patients with acute ischemic stroke were included. Pooled adjusted risk ratio (RR) and corresponding 95% confidence interval (CI) were obtained using a random effect model. Twelve studies involving 7905 acute ischemic stroke patients met our inclusion criteria. From the overall pooled analysis, patients with elevated cardiac troponin were significantly associated with increased risk of all-cause mortality (RR: 2.53; 95% CI: 1.83–3.50). The prognostic value of cardiac troponin elevation on all-cause mortality risk was stronger (RR: 3.54; 95% CI: 2.09–5.98) during in-hospital stay. Further stratified analysis showed elevated cTnT (RR: 2.36; 95% CI: 1.47–3.77) and cTnI (RR: 2.79; 95% CI: 1.68–4.64) level conferred the similar prognostic value of all-cause mortality. Acute ischemic stroke patients with elevated cTnT or cTnI at baseline independently predicted an increased risk of all-cause mortality. Determination of cardiac troponin on admission may aid in the early death risk stratification in these patients.

Correlation of elevated cardiac troponin T level with severity and in-hospital outcomes in patients with acute ischemic stroke

Background: Although elevated cardiac troponin T (cTnT) is a specific marker of acute coronary syndrome, its increment in patients with acute ischemic stroke is not clear. The aim of this study is to identify the relationship between high cTnT levels and stroke severity as well as in-hospital outcomes. Materials and Methods: This observational, cross-sectional study was conducted on 100 patients with acute ischemic stroke in Rizgary teaching hospital from January 2016 to January 2017. Patients were divided into two groups: Group 1 patients (n = 61) with normal cTnT level and Group 2 patients (n = 39) with elevated cTnT level. The relationships between cTnT levels and stroke severity as well as in-hospital outcomes were assessed and compared between the two groups. Results: In this study, cTnT was raised in 39 patients (39%). Patients with elevated cTnT levels were mainly males, had a significantly higher prevalence of hypertension and diabetes mellitus than the normal cTnT group (P

Cardiac Troponin Release is Associated with Biomarkers of Inflammation and Ventricular Dilatation During Critical Illness.

ABSTRACTIntroduction:Troponin release is common during critical illness. We hypothesized that there was an association between cardiac troponin T (cTnT) and biomarkers of systemic inflammation and ventricular dilatation.Methods:In an observational prospective cohort study, we enrolled consecutive adult patients admitted for noncardiac reasons to the intensive care unit (ICU) in two tertiary care centers. We measured cTnT, C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT), and N-terminal pro brain natriuretic peptide (NT-proBNP) daily in the first week, and on alternate days in the second week. Using a peak cTnT cutoff ≥15 ng/L and concomitant changes on electrocardiogram, patients were categorized as “definite myocardial infarction (MI),” “possible MI,” “cTnT rise only,” or “no cTnT rise.” Within each group, associations between CRP, IL-6, PCT, NT-proBNP, and cTnT were investigated using mixed effect models.Results:One hundred seventy-two patients were included in the analysis of whom 84% had a cTnT rise ≥15 ng/L. Twenty-one patients (12%) had a definite MI, 51 (30%) had a possible MI, and 73 (42%) had a cTnT rise only. At the time of peak cTnT, 71% of patients were septic and 67% were on vasopressors.Multivariable analysis showed a significant association between cTnT and IL-6 in all patients with a cTnT rise independent of age, gender, renal function, and cardiovascular risk factors. In patients without a definite MI, cTnT levels were significantly associated with PCT and NT-proBNP values. In patients without elevated cTnT levels, there was no associated NT-proBNP rise.Conclusions:In ICU patients admitted for non-cardiac reasons, serial cTnT levels were independently associated with markers of systemic inflammation and NT-proBNP.

High-sensitivity cardiac troponin T predicts mortality after hospitalization for community-acquired pneumonia.

Mortality after hospitalization with community-acquired pneumonia (CAP) is high, compared with age-matched controls. Available evidence suggests a strong link with cardiovascular disease. Our aim was to explore the prognostic value of high-sensitivity cardiac troponin T (cTnT) for mortality in patients hospitalized with CAP. CTnT level on admission was measured (assay conducted in 2015) in 295 patients hospitalized with CAP who participated in a randomized placebo-controlled double-blind trial on adjunctive dexamethasone treatment. Outcome measures were short- (30-day) and long-term (4.1-year) mortalities. CTnT levels were elevated (≥14 ng/L) in 132 patients (45%). Pneumonia severity index (PSI) class was 4-5 in 137 patients (46%). Short- and long-term mortality were significantly higher in patients with elevated cTnT levels. cTnT level on admission combined with PSI classification was significantly better in predicting short-term mortality (area under the operating curve (AUC) = 0.903; 95% CI = 0.847-0.960), compared with PSI classification alone (AUC = 0.818; 95% CI = 0.717-0.919). An optimal cTnT cut-off level of 28 ng/L was independently associated with both short- and long-term mortality (OR = 21.9; 95% CI = 4.7-101.4 and 10.7; 95% CI = 5.0-22.8, respectively). Elevated cTnT level on admission is a strong predictor of short- and long-term mortalities in patients hospitalized with CAP.

Strong diurnal rhythm of troponin T, but not troponin I, in a patient with renal dysfunction

Cardiac troponin T (cTnT) and I (cTnI), measured with high-sensitive assays, are the preferred biomarkers for the diagnosis of acute myocardial infarction [ 1 Roffi M. Patrono C. Collet J.P. Mueller C. Valgimigli M. Andreotti F. et al. 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: Task Force for the Management of Acute Coronary Syndromes in Patients Presenting without Persistent ST-Segment Elevation of the European Society of Cardiology (ESC). Eur. Heart J. 2016; 37: 267-315 Crossref PubMed Scopus (4337) Google Scholar , 2 Mills N.L. Churchhouse A.M. Lee K.K. Anand A. Gamble D. Shah A.S. et al. Implementation of a sensitive troponin I assay and risk of recurrent myocardial infarction and death in patients with suspected acute coronary syndrome. JAMA. 2011; 305: 1210-1216 Crossref PubMed Scopus (271) Google Scholar ]. Serial cardiac troponin measurements, and the interpretation of a “troponin rise-or-fall” in patients with chest pain discriminate between acute and chronic troponin elevations [ [1] Roffi M. Patrono C. Collet J.P. Mueller C. Valgimigli M. Andreotti F. et al. 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: Task Force for the Management of Acute Coronary Syndromes in Patients Presenting without Persistent ST-Segment Elevation of the European Society of Cardiology (ESC). Eur. Heart J. 2016; 37: 267-315 Crossref PubMed Scopus (4337) Google Scholar ]. This diagnostic concept assumes that troponin levels in patients without acute cardiac injury fluctuate randomly around an individual's homeostatic setpoint. However, it has recently been demonstrated that cTnT exhibits a diurnal rhythm [ 3 Klinkenberg L.J. van Dijk J.W. Tan F.E. van Loon L.J. van Dieijen-Visser M.P. Meex S.J. Circulating cardiac troponin T exhibits a diurnal rhythm. J. Am. Coll. Cardiol. 2014; 63: 1788-1795 Abstract Full Text Full Text PDF PubMed Scopus (65) Google Scholar , 4 Aakre K.M. Roraas T. Petersen P.H. Svarstad E. Sellevoll H. Skadberg O. et al. Weekly and 90-minute biological variations in cardiac troponin T and cardiac troponin I in hemodialysis patients and healthy controls. Clin. Chem. 2014; 60: 838-847 Crossref PubMed Scopus (75) Google Scholar ]. The amplitude of the diurnal cTnT rhythm and its diagnostic implication in patients with chronically elevated cTnT levels are unexplored. Also, whether cTnT and cTnI are equally affected by rhythmic diurnal oscillation is unknown.

Does cardiac rhythm monitoring in patients with elevated troponin levels lead to changes in management?

We sought to identify the frequency of arrhythmias in patients with elevated cardiac troponin levels and without ST-segment elevation myocardial infarction or a primary arrhythmia, and to determine whether detection of an arrhythmia leads to management changes. A review of 1381 consecutive patients admitted from the emergency department for rhythm monitoring with an elevated cardiac troponin T (cTnT) level was performed. Patients admitted to an intensive care unit and those with an initial primary arrhythmia were excluded. Troponin values were obtained on admission, at 3 hours and at 6 hours. Electronic medical records and all rhythm recordings were reviewed for documentation of an arrhythmia and any changes in management. An arrhythmia was detected in 26% of the 330 patients who met the inclusion criteria. Those with arrhythmias had higher rates of coronary artery disease and prior percutaneous coronary intervention ( p = 0.02 and p = 0.01, respectively). Those with arrhythmias had higher mean cTnT values compared to those without arrhythmias ( p = 0.02 at 3 hours and p = 0.006 at 6 hours) even after controlling for a discharge diagnosis of acute coronary syndrome. Changes in management in response to the detection of arrhythmias were infrequent (6.3%) and usually included only changes in medication doses. Patients admitted with an elevated cTnT level to a non-intensive care unit rhythm-monitored bed without ST-segment elevation myocardial infarction or primary arrhythmia have a high incidence of arrhythmias; however, changes in management are infrequent.

Elevated Plasma Cardiac Troponin T Levels Caused by Skeletal Muscle Damage in Pompe Disease.

Elevated plasma cardiac troponin T (cTnT) levels in patients with neuromuscular disorders may erroneously lead to the diagnosis of acute myocardial infarction or myocardial injury. In 122 patients with Pompe disease, the relationship between cTnT, cardiac troponin I, creatine kinase (CK), CK-myocardial band levels, and skeletal muscle damage was assessed. ECG and echocardiography were used to evaluate possible cardiac disease. Patients were divided into classic infantile, childhood-onset, and adult-onset patients. cTnT levels were elevated in 82% of patients (median 27 ng/L, normal values <14 ng/L). Cardiac troponin I levels were normal in all patients, whereas CK-myocardial band levels were increased in 59% of patients. cTnT levels correlated with CK levels in all 3 subgroups (P<0.001). None of the abnormal ECGs recorded in 21 patients were indicative of acute myocardial infarction, and there were no differences in cTnT levels between patients with and without (n=90) abnormalities on ECG (median 28 ng/L in both groups). The median left ventricular mass index measured with echocardiography was normal in all the 3 subgroups. cTnT mRNA expression in skeletal muscle was not detectable in controls but was strongly induced in patients with Pompe disease. cTnT protein was identified by mass spectrometry in patient-derived skeletal muscle tissue. Elevated plasma cTnT levels in patients with Pompe disease are associated with skeletal muscle damage, rather than acute myocardial injury. Increased cTnT levels in Pompe disease and likely other neuromuscular disorders should be interpreted with caution to avoid unnecessary cardiac interventions.

Correlations of arterial stiffness/central hemodynamics with serum cardiac troponin T and natriuretic peptide levels in a middle-aged male worksite cohort

BackgroundElevated serum levels of cardiac troponin T (cTnT) and N-terminal fragment of B-type natriuretic peptide (NT-proBNP), and also increased arterial stiffness/abnormal central hemodynamics, are well-known risk factors for future cardiovascular events. The present study was conducted to clarify which of the two – the serum level of cTnT or that of NT-proBNP – might be more closely associated with the arterial stiffness/central hemodynamics. MethodsIn 2374 male employees of a company (46±9 years), the following parameters were measured: second peak of the radial systolic pressure waveform (SP2), radial augmentation index (rAI), PP2 (SP2 minus the diastolic blood pressure), brachial-ankle pulse wave velocity (baPWV), and serum levels of cTnT and NT-pro BNP. ResultsAfter adjustments for confounding variables, binary logistic regression analyses demonstrated that baPWV was associated with a significant odds ratio for serum NT-proBNP ≥125pg/mL (1.690; 95% confidence interval=1.136–2.514, p=0.002) and rAI was associated with a significant odds ratio for serum NT-proBNP ≥55pg/mL (1.205; 95% confidence interval=1.012–1.435, p=0.036). The baPWV, rAI, SP2, and PP2 were not associated with significant odds ratios for elevated serum cTnT levels (≥0.014ng/mL and ≥0.010ng/mL). ConclusionsIn the middle-aged male worksite cohort studied, increased arterial stiffness/abnormal central hemodynamics appeared to be associated with elevated serum NT-proBNP levels, rather than with minimally elevated serum cTnT levels. This difference may be one of the plausible explanations for the independency of the predictive values of the two serum markers for future cardiovascular events.