BACKGROUND:Patients with suspected acute coronary syndrome (ACS) in whom myocardial infarction has been ruled out are still at risk of having obstructive coronary artery disease (CAD).This rate is higher among patient...BACKGROUND:Patients with suspected acute coronary syndrome (ACS) in whom myocardial infarction has been ruled out are still at risk of having obstructive coronary artery disease (CAD).This rate is higher among patients with intermediate high-sensitivity troponin I (hsTnI) concentrations (5 ng/L to 99th percentile) than low concentrations (<5 ng/L).Therefore,an intermediate concentration has been suggested as a candidate for downstream investigation with computed tomography coronary angiography(CTCA).We tried to compare the HEART score-guided vs.hsTnI-guided approach for identifying obstructive CAD.METHODS:From a prospective cohort study of patients presenting to the emergency department with suspected ACS,433 patients without elevated hsTnI who also underwent CTCA were selected and analyzed.The performances of hsTnI concentration and HEART score were compared using sensitivity,specificity,positive predictive value (PPV),and negative predictive value (NPV).RESULTS:Overall,120 (27.7%) patients had obstructive CAD.Patients with intermediate hsTnI concentrations were more likely to have obstructive CAD than those with low hsTnI concentrations(40.0%vs.18.1%);patients with non-low-risk HEART scores (≥4 points) were also more likely to have obstructive CAD than those with low-risk scores (0 to 3 points)(41.0%vs.7.6%).The HEART score had higher sensitivity and NPV for detecting obstructive CAD in each classification than hsTnI concentration (sensitivity:89.2%vs.63.3%;NPV:92.4%vs.81.9%,respectively).CONCLUSION:After excluding myocardial infarction in patients with suspected ACS,adding the HEART score for selecting candidates for CTCA could improve patient risk stratification more accurately than relying on hsTnI concentration.展开更多
BACKGROUND There are indications that viral myocarditis,demand ischemia,and renin-angio-tensin-aldosterone system pathway activation play essential roles in troponin elevation in coronavirus disease 2019(COVID-19)pati...BACKGROUND There are indications that viral myocarditis,demand ischemia,and renin-angio-tensin-aldosterone system pathway activation play essential roles in troponin elevation in coronavirus disease 2019(COVID-19)patients.Antiviral medications and steroids are used to treat viral myocarditis,but their effect in patients with elevated troponin,possibly from myocarditis,has not been studied.AIM To evaluate the effect of dexamethasone,remdesivir,and angiotensin-converting enzyme(ACE)inhibitors(ACEI)on mortality in COVID-19 patients with elevated troponin.METHODS Our retrospective observational study involved 1788 COVID-19 patients at seven hospitals in Southern California,United States.We did a backward selection Cox multivariate regression analysis to determine predictors of mortality in our study population.Additionally,we did a Kaplan Meier survival analysis in the subset of patients with elevated troponin,comparing survival in patients that received dexamethasone,remdesivir,and ACEI with those that did not.RESULTS The mean age was 66 years(range 20-110),troponin elevation was noted in 11.5%of the patients,and 29.9%expired.The patients'age[hazard ratio(HR)=1.02,P<0.001],intensive care unit admission(HR=5.07,P<0.001),and ventilator use(HR=0.68,P=0.02)were significantly associated with mortality.In the subset of patients with elevated troponin,there was no statistically significant difference in survival in those that received remdesivir(0.07),dexamethasone(P=0.63),or ACEI(P=0.8)and those that did not.CONCLUSION Although elevated troponin in COVID-19 patients has been associated with viral myocarditis and ACE II receptors,conventional viral myocarditis treatment,including antiviral and steroids,and ACEI did not show any effect on mortality in these patients.展开更多
Introduction: Pulmonary embolism is a diagnostic and therapeutic emergency that can be life-threatening. Its mortality is largely attributable to severe forms classically defined by clinical and morphological criteria...Introduction: Pulmonary embolism is a diagnostic and therapeutic emergency that can be life-threatening. Its mortality is largely attributable to severe forms classically defined by clinical and morphological criteria. The aim of this study is to establish the role of two cardiac biomarkers (NT-proBNP and troponin) in assessing the severity of pulmonary embolism. Patients and Methods: We conducted a descriptive and analytical cross-sectional study. Data collection was retrospective over the period from January 1, 2011 to December 31, 2021. All patients hospitalized for pulmonary embolism in two cardiology referral clinics in Cotonou (Atinkanmey Polyclinic and CICA Clinic) were included. Results: The hospital prevalence of pulmonary embolism was 9.08%. The mean age was 52.6 years, with extremes of 18 and 92 years. The sex ratio was 0.73. Pulmonary embolism was severe according to hemodynamic, morphological and sPESI criteria in 12%, 24% and 39% of cases respectively, and mortality was 61.53%. Mean NT-ProBNP and troponin I levels were significantly higher in patients with severe criteria than in those without. NT-proBNP and troponin had good specificity for predicting cardiovascular arrest (99% and 90%), shock (100% and 98%), and hypotension (99% and 96%). NT-proBNP has the best positive predictive values in relation to the occurrence of shock (100%) and right ventricular dilatation (93%). The best correlation coefficient was obtained between right ventricular dilatation and NT-proBNP (0.78). Conclusion: NT-proBNP and troponin I are good biomarkers for predicting the severity of pulmonary embolism and allowing therapeutic adaptation when they are elevated.展开更多
High-sensitivity cardiac troponin(hs-cTn) assays are increasingly being used in many countries worldwide,however,a generally accepted definition of high-sen-sitivity is still pending.These assays enable cTn mea-sureme...High-sensitivity cardiac troponin(hs-cTn) assays are increasingly being used in many countries worldwide,however,a generally accepted definition of high-sen-sitivity is still pending.These assays enable cTn mea-surement with a high degree of analytical sensitivity with a low analytical imprecision at the low measuring range of cTn assays(coefficient of variation of < 10% at the 99th percentile upper reference limit).One of the most important advantages of these new assays is that they allow novel,more rapid approaches to rule in or rule out acute coronary syndromes(ACSs) than with previous cTn assay generations which are still more commonly used in practice worldwide.hs-cTn is also more sensitive for the detection of myocardial damage unrelated to acute myocardial ischemia.Therefore,the increase in early diagnostic sensitivity of hs-cTn assays for ACS comes at the cost of a reduced ACS specificity,because more patients with other causes of acute or chronic myocardial injury without overt myocardial isch-emia are detected than with previous cTn assays.As hs-cTn assays are increasingly being adopted in clinical practice and more hs-cTn assays are being developed,this review attempts to synthesize the available clinical data to make recommendations for their everyday clini-cal routine use.展开更多
BACKGROUND:Early reperfusion can effectively treat acute myocardial infarction(AMI) and reduce the mortality signif icantly. This study aimed to compare the role of plasma microRNA-1(miR-1) and cardiac troponin T(cTnT...BACKGROUND:Early reperfusion can effectively treat acute myocardial infarction(AMI) and reduce the mortality signif icantly. This study aimed to compare the role of plasma microRNA-1(miR-1) and cardiac troponin T(cTnT) in early diagnosis of AMI patients.METHODS:From May 2011 to May 2012,plasma samples were collected from 56 AMI patients and 28 non-AMI controls. The expression of plasma miR-1 was measured by quantitative reverse transcription-polymerase chain reaction(qRT-PCR),and the level of plasma cTnT was measured using electrochemiluminescence-based methods on an Elecsys 2010 Immunoassay Analyzer. SPSS 16.0 was used for the statistical analysis of the results. Data were expressed as mean±standard deviation unless otherwise described. The differences about clinical characteristics between the AMI patients and controls were tested using Student's t test or Fisher's exact test. The Mann-Whitney U test was conducted to compare the expression of microRNAs between the AMI patients and controls. MicroRNAs expression between different intervals of the AMI patients was compared using Wilcoxon's signed-rank test. The receiver operating characteristic(ROC) curve was established to discriminate the AMI patients from the controls.RESULTS:In the present study,the expression of plasma miR-1 was signifi cantly increased in the AMI patients compared with the healthy controls(P<0.01). The plasma miR-1 in the AMI patients decreased to the normal level at 14 days(P>0.05). The expression of plasma miR-1 was not related to the clinical characteristics of the study population(P>0.05). ROC curve analyses demonstrated that miR-1 was specifi c and sensitive for the early diagnosis of AMI,but not superior to cTnT.CONCLUSION:Plasma miR-1 could be used in the early diagnosis of AMI,but it is similar to cTnT.展开更多
BACKGROUND:The early diagnosis of acute myocardial infarction(AMI)remains challenging,especially for institutions without the high-sensitive cardiac troponin(hs-c Tn)assay.Herein,we aim to assess the value of creatine...BACKGROUND:The early diagnosis of acute myocardial infarction(AMI)remains challenging,especially for institutions without the high-sensitive cardiac troponin(hs-c Tn)assay.Herein,we aim to assess the value of creatine kinase-myocardial band isoenzyme(CK-MB)combined with different cardiac troponin(c Tn)assays in AMI diagnosis.METHODS:This multicenter,observational study included 3,706 patients with acute chest pain from September 1,2015,to September 30,2017.We classified the participants into three groups according to the c Tn assays:the point-of-care c Tn(POC-c Tn)group,the contemporary c Tn(c-c Tn)group,and hs-c Tn group.The diagnostic value was quantified using sensitivity and the area under the curve(AUC).RESULTS:Compared to the single POC-c Tn/c-c Tn assays,combining CK-MB and POC-c Tn/c-c Tn increased the diagnostic sensitivity of AMI(56.1%vs.63.9%,P<0.001;82.7%vs.84.3%,P=0.025).In contrast,combining CK-MB and hs-c Tn did not change the sensitivity compared with hs-c Tn alone(95.0%vs.95.0%,P>0.999).In the subgroup analysis,the sensitivity of combining CKMB and c-c Tn increased with time from symptom onset<6 h compared with c-c Tn alone(72.8%vs.75.0%,P=0.046),while the sensitivity did not increase with time from symptom onset>6 h(97.5%vs.98.3%,P=0.317).The AUC of the combination of CK-MB and POC-c Tn significantly increased compared to the single POC-c Tn assay(0.776 vs.0.750,P=0.002).The AUC of the combined CKMB and c-c Tn/hs-c Tn assays did not significantly decrease compared with that of the single c-c Tn/hs-c Tn assays within 6 h.CONCLUSIONS:The combination of CK-MB and POC-c Tn or c-c Tn may be valuable for the early diagnosis of AMI,especially when hs-c Tn is not available.展开更多
Convenient,rapid,and accurate detection of cardiac troponin I(cTnI)is crucial in early diagnosis of acute myocardial infarction(AMI).A paper-based electrochemical immunosensor is a promising choice in this field,becau...Convenient,rapid,and accurate detection of cardiac troponin I(cTnI)is crucial in early diagnosis of acute myocardial infarction(AMI).A paper-based electrochemical immunosensor is a promising choice in this field,because of the flexibility,porosity,and cost-efficacy of the paper.However,paper is poor in electronic conductivity and surface functionality.Herein,we report a paper-based electrochemical immunosensor for the label-free detection of cTnI with the working electrode modified by MXene(Ti_(3)C_(2))nanosheets.In order to immobilize the bio-receptor(anti-cTnI)on the MXene-modified working electrode,the MXene nanosheets were functionalized by aminosilane,and the functionalized MXene was immobilized onto the surface of the working electrode through Nafion.The large surface area of the MXene nanosheets facilitates the immobilization of antibodies,and the excellent conductivity facilitates the electron transfer between the electrochemical species and the underlying electrode surface.As a result,the paper-based immunosensor could detect cTnI within a wide range of 5-100 ng/mL with a detection limit of 0.58 ng/mL.The immunosensor also shows outstanding selectivity and good repeatability.Our MXene-modified paper-based electrochemical immunosensor enables fast and sensitive detection of cTnI,which may be used in real-time and cost-efficient monitoring of AMI diseases in clinics.展开更多
Background:Cardiac troponin assays have improved the ability to detect myocardial damage.However,ascertaining whether troponin elevation is due to myocardial infarction(MI) or secondary to another process can be chall...Background:Cardiac troponin assays have improved the ability to detect myocardial damage.However,ascertaining whether troponin elevation is due to myocardial infarction(MI) or secondary to another process can be challenging.Our aim is to evaluate provider-level variation in the diagnosis of MI and the use of invasive coronary angiography(ICA) among patients with undifferentiated elevations in cardiac troponin.Methods:We analyzed data from all patients with elevated troponin levels in a single Veterans Affairs(VA) Medical Center between 2006 and 2007.One of several cardiologists prospectively evaluated each patient's presentation and course of care.We compared the frequency of MI diagnosis and ICA use between physicians using univariate odds ratios(OR).Results:Among 761 patients,34.0% were diagnosed with MI and 25.9% underwent ICA.The unadjusted rates of MI(23.9% to 56.7%,P=0.02) and ICA(17.3% to 73.3%,P<0.001) differed between physicians.Comparing the patient cohorts for each physician,baseline characteristics were similar except for chest pain.In multivariate regression,factors associated with the use of cardiac ICA included an abnormal electrocardiograph(ECG)(OR=1.89,P=0.014),level of troponin(OR=1.71,P=0.004),chest pain(OR=8.60,P<0.001),and care by non-VA physicians(OR=4.45,P=0.006).One physician had a lower ICA use(OR=0.56,P=0.017).In multivariate regression of MI,no physician-level variation was observed.Conclusion:Among patients with elevated troponin,the likelihood of being diagnosed with MI and undergoing ICA is dependent on their clinical presentation.After adjustment,physician-level variation in care was observed for the use of ICA,but not for the diagnosis of MI.展开更多
AIM: To identify the typical shape of the rise and fall curve of troponin(Tn) following the different types of myocardial infarction(MI). METHODS: We conducted a systematic search in PubM ed and Embase including all s...AIM: To identify the typical shape of the rise and fall curve of troponin(Tn) following the different types of myocardial infarction(MI). METHODS: We conducted a systematic search in PubM ed and Embase including all studies which focused on the kinetics of Tn in MI type 1, type 4 and type 5. Tn levels were standardized using the 99 th percentile, a pooled mean with 95%CI was calculated from the weighted means for each time point until 72 h. RESULTS: A total of 34 of the 2528 studies identified in the systematic search were included. The maximum peak level of the Tn was seen after 6 h after successful reperfusion of an acute MI, after 12 h for type 1 MI and after 72 h for type 5 MI. In type 1 MI there were additional smaller peaks at 1 h and at 24 h. After successful reperfusion of an acute MI there was a second peak at 24 h. There was not enough data available to analyze the Tn release after MI associated with percutaneous coronary intervention(type 4).CONCLUSION: The typical rise and fall of Tn is different for type 1 MI, successful reperfusion of an acute MI and type 5 MI, with different timing of the peak levels and different slopes of the fall phase.展开更多
BACKGROUND Evaluation of suspected stable angina patients with probable coronary artery disease(CAD)in the community is challenging.In the United Kingdom,patients with suspected stable angina are referred by community...BACKGROUND Evaluation of suspected stable angina patients with probable coronary artery disease(CAD)in the community is challenging.In the United Kingdom,patients with suspected stable angina are referred by community physicians to be assessed by specialists within the hospital system in rapid access chest pain clinics(RACPC).The role of a highly sensitive troponin I(uscTnI)assay in the diagnosis of suspected CAD in a RACPC in a“real-life”setting in a non-academic hospital has not been explored.AIM To examine the diagnostic value of uscTnI(detection limit 0.12 ng/L,upper reference range 8.15 ng/L,and detected uscTnI in 96.8%of the reference population),in the evaluation of stable CAD in a non-selected patient group,with several co-morbidities,who presented to the RACPC.METHODS One hundred and seventy two RACPC patients were assigned to either functional or anatomical testing according to the hospital protocol.RESULTS The investigations offered to patients were exercise tolerance test 7.6%,24 h ECG 1.2%,Echocardiogram 14.5%,stress echocardiogram 8.1%,coronary computed tomography angiography(CCTA)12.8%,coronary angiogram 13.4%,17.4%were diagnosed with non-cardiac chest pain,3.5%treated as stable angina,8.2%reviewed by cardiologists,electronic medical records were not available in 10.4%.Receiver operating characteristic curves for CAD used uscTnI values measured in patients who underwent functional testing,angiogram or CCTA.Values>0.52 ng/L showed 100%sensitivity and at>11.6 ng/L showed 100%specificity.In the range>0.52-11.6 ng/L,uscTnI may not have the same diagnostic potential.In patients assigned to coronary angiogram higher concentrations of uscTnI was associated with severe CAD.Low levels of uscTnI and low pre-test probability of CAD(QRISK3)may decrease patient numbers assigned to CCTA.CONCLUSION The uscTnI diagnostic cut-off values in a RACPC will depend on patient population and their presenting co-morbidity.In the presence of clinical comorbidities and previous CAD the uscTnI needs to be used in conjunction with clinical assessment.展开更多
Objective:To study the usefulness of traditional lipid profile levels in screening subjects who had developed chest pain due lo cardiac event as indicated by a positive troponin I test.Methods:In this retrospective st...Objective:To study the usefulness of traditional lipid profile levels in screening subjects who had developed chest pain due lo cardiac event as indicated by a positive troponin I test.Methods:In this retrospective study data of ihe 430 patients presented lo the emergency department with symptoms of cardiac ischemia who underwent both troponin and lipid profiles tests were compared with the lipid profiles of 165 normal healthy subjects(controls).The troponin was detected qualitatively when a specimen contains troponin I(cTnI)above the 99th percentile(TnI>0.5 ng/mL).The total cholesterol,high density lipoproteins cholesterol,very low density lipoproteins and Iriacvl glycerol levels were also analyzed and Ion densilv lipoprotein level was calculated using Friedewald's formula.Results:Patients with chest pain and positive troponin test(with confirmed cardiac event)were found lo have significantly elevated levels of total cholesterol,triacyl glycerol levels,low density lipoprotein level and significantly reduced high densilv lipoproteins cholesterol levels when compared lo the patients who experienced only chesl pain(negative troponin)and healthy controls.Conclusions:Traditional lipid profile levels is still can be used in screening popiilalions lo identify the subjecis with high risk of developing cardiacevent in case if the laboratory set up has not troponin test facilities.展开更多
BACKGROUND Release of cardiac biomarkers is common after strenuous endurance exercise,but data on intermittent exercise are scarce.It has not been investigated whether cardiac troponin elevation is influenced dependin...BACKGROUND Release of cardiac biomarkers is common after strenuous endurance exercise,but data on intermittent exercise are scarce.It has not been investigated whether cardiac troponin elevation is influenced depending on the type of exercise that an athlete is adapted to perform.We hypothesized that intermittent but not continuous exercise induces cardiac troponin elevation in professional athletes adapted to high-intensity intermittent exercise.AIM To examine how training specificity impacts high-sensitivity cardiac troponin T(hs-cTnT)release.METHODS Nine professional floorball players participated in the study,which comprised two different exercise tests:a continuous incremental cycle ergometer test and a Yo-Yo Intermittent Recovery 2(Yo-Yo IR2)test.Serial assessment of hs-cTnT was performed after the cycle ergometer test and the Yo-Yo IR2 test(baseline,0,2,6,and 24 h).RESULTS No hs-cTnT elevation above the myocardial damage cutoff(≥14 ng/L)was shown after the cycle ergometer test,whereas hs-cTnT levels rose over the cutoff in three of nine participants after the Yo-Yo IR2 test.The hs-cTnT levels peaked at 6 h after both tests,but were significantly higher after the Yo-Yo IR2 test compared to the cycle ergometer test(median hs-cTnT concentration 10.6 ng/L vs 7.8 ng/L,P=0.038).All levels returned to baseline within 24 h.CONCLUSION In professional athletes adapted to high-intensity intermittent exercise,hs-cTnT was significantly elevated after intermittent but not continuous exercise.This principle of specificity training should be considered when designing future studies to avoid misinterpretation of hs-cTnT elevation.展开更多
Troponin is a complex of three proteins (troponin I, troponin C, and troponin T) that binds Ca2+ and is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of troponin I (TnI) ...Troponin is a complex of three proteins (troponin I, troponin C, and troponin T) that binds Ca2+ and is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of troponin I (TnI) in vertebrates has been extensively characterized, but its role in molluscan muscles has not yet been elucidated. Our previous work suggested that the troponin C subunit has a role in adductor phasic muscle but not in catch muscle. Here, we investigated the molecular characteristics of TnI from the bivalve Japanese pearl oyster, Pinctada fucata to aid the elucidation of the function of molluscan muscle troponin. We determined the primary structure of the full-length TnI protein from the P. fucata adductor muscle (Pifuc-TnI) and found that it is composed of 286 amino acid residues with a predicted molecular weight of 33,737. Motif structure predictions and multiple sequence alignments revealed that Pifuc-TnI has a 138 residue extension at its N-terminus compared with rabbit TnI. This is analogous to characterized TnIs from other mollusks. However, unlike scallop TnI, Pifuc-TnI is predicted to contain two cAMP-dependent protein kinase phosphorylation sites, at residues 39 - 45 (RRGTEDD) and 145 - 151 (KKKSKRK). Phylogenetic analysis indicated that Pifuc-TnI and molluscan TnIs were grouped into the same clade. Pifuc-TnI gene structure predictions using Splign alignment of our obtained cDNA and genome sequences indicated that Pifuc-TnI consists of fifteen exons, with the start and stop codons located in exon 2 and exon 11, respectively. Using quantitative real-time PCR, we determined that the Pifuc-TnI gene is predominantly expressed in adductor phasic muscle, weakly in adductor catch muscle, and is not expressed in the gill, mantle or foot. These findings suggest that TnI, as a component of the troponin complex, plays a regulatory role in adductor phasic muscle contraction, but not in catch contraction.展开更多
Acute myocardial infarction(AMI)is a major health problem leading to high rates of mortality and morbidity.Biomarker cardiac troponin I(cTnI)has shown high sensitivity and specificity towards AMI detection,and has bee...Acute myocardial infarction(AMI)is a major health problem leading to high rates of mortality and morbidity.Biomarker cardiac troponin I(cTnI)has shown high sensitivity and specificity towards AMI detection,and has been regarded as"gold standard".An ultrasensitive method to detectcTnI with low concentration in human fluid is essential.In this paper,we developed an aptamer-based assay coupled with rolling circle amplification(RCA)and molecular beacon probe for sensitive detection ofcTnI.In this strategy,aptamer acts as a bridge to communicate between oligonucleotides andcTnI.RCA reaction produces a single-stranded tandem repeated copy of the circular template,which are recognized by fluorescence molecular beacon probe.With this strategy,highly sensitive and specific detection of cTnI was realized with the lowest detectable concentration of 7.24 pg/m L.The developed aptamer-RCA assay can be a promising tool in clinical samples analysis.The assay can also analyze other disease-related biomarkers by replacing the aptamer.展开更多
Troponin C (TnC) is one of the subunits of troponin. Troponin, which is activated by Ca2+ binding, is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of TnC in vertebrates ...Troponin C (TnC) is one of the subunits of troponin. Troponin, which is activated by Ca2+ binding, is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of TnC in vertebrates has been characterized in detail, but the role of TnC in molluscan muscles is still unclear. In this work, we investigated whether TnC plays a role in the catch contraction of molluscan smooth muscle in the bivalve Japanese pearl oyster Pinctada fucata. We determined the full-length primary structure of the TnC protein from the P. fucata adductor muscle (Pifuc-TnC), and found it is composed of 150 amino acid residues with a predicted molecular weight of 17,400. Multiple sequence alignments indicated that it had four EF-hand motifs, but only one (site IV) was predicted to have Ca2+-binding ability. This is analogous to characterized TnCs from other mollusks. Three-dimensional modeling of Pifuc-TnC using SWISS-MODEL indicated the presence of a short loop within the α-helix connecting the site II and III EF-hand motifs. We predicted the gene structure of Pifuc-TnC using Splign alignment of our obtained cDNA and genome sequences and elucidated that Pifuc-TnC consists of five exons, with the start and stop codons located in exon 1 and exon 5, respectively. Using quantitative real-time PCR, we determined that the Pifuc-TnC gene is predominantly expressed in adductor phasic muscle and rarely in adductor catch muscle, gill, mantle and foot. These findings suggest that TnC may not have a role in catch muscle contraction.展开更多
文摘BACKGROUND:Patients with suspected acute coronary syndrome (ACS) in whom myocardial infarction has been ruled out are still at risk of having obstructive coronary artery disease (CAD).This rate is higher among patients with intermediate high-sensitivity troponin I (hsTnI) concentrations (5 ng/L to 99th percentile) than low concentrations (<5 ng/L).Therefore,an intermediate concentration has been suggested as a candidate for downstream investigation with computed tomography coronary angiography(CTCA).We tried to compare the HEART score-guided vs.hsTnI-guided approach for identifying obstructive CAD.METHODS:From a prospective cohort study of patients presenting to the emergency department with suspected ACS,433 patients without elevated hsTnI who also underwent CTCA were selected and analyzed.The performances of hsTnI concentration and HEART score were compared using sensitivity,specificity,positive predictive value (PPV),and negative predictive value (NPV).RESULTS:Overall,120 (27.7%) patients had obstructive CAD.Patients with intermediate hsTnI concentrations were more likely to have obstructive CAD than those with low hsTnI concentrations(40.0%vs.18.1%);patients with non-low-risk HEART scores (≥4 points) were also more likely to have obstructive CAD than those with low-risk scores (0 to 3 points)(41.0%vs.7.6%).The HEART score had higher sensitivity and NPV for detecting obstructive CAD in each classification than hsTnI concentration (sensitivity:89.2%vs.63.3%;NPV:92.4%vs.81.9%,respectively).CONCLUSION:After excluding myocardial infarction in patients with suspected ACS,adding the HEART score for selecting candidates for CTCA could improve patient risk stratification more accurately than relying on hsTnI concentration.
文摘BACKGROUND There are indications that viral myocarditis,demand ischemia,and renin-angio-tensin-aldosterone system pathway activation play essential roles in troponin elevation in coronavirus disease 2019(COVID-19)patients.Antiviral medications and steroids are used to treat viral myocarditis,but their effect in patients with elevated troponin,possibly from myocarditis,has not been studied.AIM To evaluate the effect of dexamethasone,remdesivir,and angiotensin-converting enzyme(ACE)inhibitors(ACEI)on mortality in COVID-19 patients with elevated troponin.METHODS Our retrospective observational study involved 1788 COVID-19 patients at seven hospitals in Southern California,United States.We did a backward selection Cox multivariate regression analysis to determine predictors of mortality in our study population.Additionally,we did a Kaplan Meier survival analysis in the subset of patients with elevated troponin,comparing survival in patients that received dexamethasone,remdesivir,and ACEI with those that did not.RESULTS The mean age was 66 years(range 20-110),troponin elevation was noted in 11.5%of the patients,and 29.9%expired.The patients'age[hazard ratio(HR)=1.02,P<0.001],intensive care unit admission(HR=5.07,P<0.001),and ventilator use(HR=0.68,P=0.02)were significantly associated with mortality.In the subset of patients with elevated troponin,there was no statistically significant difference in survival in those that received remdesivir(0.07),dexamethasone(P=0.63),or ACEI(P=0.8)and those that did not.CONCLUSION Although elevated troponin in COVID-19 patients has been associated with viral myocarditis and ACE II receptors,conventional viral myocarditis treatment,including antiviral and steroids,and ACEI did not show any effect on mortality in these patients.
文摘Introduction: Pulmonary embolism is a diagnostic and therapeutic emergency that can be life-threatening. Its mortality is largely attributable to severe forms classically defined by clinical and morphological criteria. The aim of this study is to establish the role of two cardiac biomarkers (NT-proBNP and troponin) in assessing the severity of pulmonary embolism. Patients and Methods: We conducted a descriptive and analytical cross-sectional study. Data collection was retrospective over the period from January 1, 2011 to December 31, 2021. All patients hospitalized for pulmonary embolism in two cardiology referral clinics in Cotonou (Atinkanmey Polyclinic and CICA Clinic) were included. Results: The hospital prevalence of pulmonary embolism was 9.08%. The mean age was 52.6 years, with extremes of 18 and 92 years. The sex ratio was 0.73. Pulmonary embolism was severe according to hemodynamic, morphological and sPESI criteria in 12%, 24% and 39% of cases respectively, and mortality was 61.53%. Mean NT-ProBNP and troponin I levels were significantly higher in patients with severe criteria than in those without. NT-proBNP and troponin had good specificity for predicting cardiovascular arrest (99% and 90%), shock (100% and 98%), and hypotension (99% and 96%). NT-proBNP has the best positive predictive values in relation to the occurrence of shock (100%) and right ventricular dilatation (93%). The best correlation coefficient was obtained between right ventricular dilatation and NT-proBNP (0.78). Conclusion: NT-proBNP and troponin I are good biomarkers for predicting the severity of pulmonary embolism and allowing therapeutic adaptation when they are elevated.
文摘High-sensitivity cardiac troponin(hs-cTn) assays are increasingly being used in many countries worldwide,however,a generally accepted definition of high-sen-sitivity is still pending.These assays enable cTn mea-surement with a high degree of analytical sensitivity with a low analytical imprecision at the low measuring range of cTn assays(coefficient of variation of < 10% at the 99th percentile upper reference limit).One of the most important advantages of these new assays is that they allow novel,more rapid approaches to rule in or rule out acute coronary syndromes(ACSs) than with previous cTn assay generations which are still more commonly used in practice worldwide.hs-cTn is also more sensitive for the detection of myocardial damage unrelated to acute myocardial ischemia.Therefore,the increase in early diagnostic sensitivity of hs-cTn assays for ACS comes at the cost of a reduced ACS specificity,because more patients with other causes of acute or chronic myocardial injury without overt myocardial isch-emia are detected than with previous cTn assays.As hs-cTn assays are increasingly being adopted in clinical practice and more hs-cTn assays are being developed,this review attempts to synthesize the available clinical data to make recommendations for their everyday clini-cal routine use.
基金supported by grants from the National Natural Science Foundation of China(81071030)the Science and Technology Foundation of Guangdong Province(2011B080701006)
文摘BACKGROUND:Early reperfusion can effectively treat acute myocardial infarction(AMI) and reduce the mortality signif icantly. This study aimed to compare the role of plasma microRNA-1(miR-1) and cardiac troponin T(cTnT) in early diagnosis of AMI patients.METHODS:From May 2011 to May 2012,plasma samples were collected from 56 AMI patients and 28 non-AMI controls. The expression of plasma miR-1 was measured by quantitative reverse transcription-polymerase chain reaction(qRT-PCR),and the level of plasma cTnT was measured using electrochemiluminescence-based methods on an Elecsys 2010 Immunoassay Analyzer. SPSS 16.0 was used for the statistical analysis of the results. Data were expressed as mean±standard deviation unless otherwise described. The differences about clinical characteristics between the AMI patients and controls were tested using Student's t test or Fisher's exact test. The Mann-Whitney U test was conducted to compare the expression of microRNAs between the AMI patients and controls. MicroRNAs expression between different intervals of the AMI patients was compared using Wilcoxon's signed-rank test. The receiver operating characteristic(ROC) curve was established to discriminate the AMI patients from the controls.RESULTS:In the present study,the expression of plasma miR-1 was signifi cantly increased in the AMI patients compared with the healthy controls(P<0.01). The plasma miR-1 in the AMI patients decreased to the normal level at 14 days(P>0.05). The expression of plasma miR-1 was not related to the clinical characteristics of the study population(P>0.05). ROC curve analyses demonstrated that miR-1 was specifi c and sensitive for the early diagnosis of AMI,but not superior to cTnT.CONCLUSION:Plasma miR-1 could be used in the early diagnosis of AMI,but it is similar to cTnT.
基金This study was supported by grants from the National Key R&D Program of China (2017YFC0908700, 2017YFC0908703)National S&T Fundamental Resources Investigation Project (2018FY100600, 2018FY100602)+2 种基金Taishan Pandeng Scholar Program of Shandong Province (tspd20181220)Taishan Young Scholar Program of Shandong Province (tsqn20161065, tsqn201812129)Key R&D Program of Shandong Province (2020SFXGFY03, 2019GSF108073)
文摘BACKGROUND:The early diagnosis of acute myocardial infarction(AMI)remains challenging,especially for institutions without the high-sensitive cardiac troponin(hs-c Tn)assay.Herein,we aim to assess the value of creatine kinase-myocardial band isoenzyme(CK-MB)combined with different cardiac troponin(c Tn)assays in AMI diagnosis.METHODS:This multicenter,observational study included 3,706 patients with acute chest pain from September 1,2015,to September 30,2017.We classified the participants into three groups according to the c Tn assays:the point-of-care c Tn(POC-c Tn)group,the contemporary c Tn(c-c Tn)group,and hs-c Tn group.The diagnostic value was quantified using sensitivity and the area under the curve(AUC).RESULTS:Compared to the single POC-c Tn/c-c Tn assays,combining CK-MB and POC-c Tn/c-c Tn increased the diagnostic sensitivity of AMI(56.1%vs.63.9%,P<0.001;82.7%vs.84.3%,P=0.025).In contrast,combining CK-MB and hs-c Tn did not change the sensitivity compared with hs-c Tn alone(95.0%vs.95.0%,P>0.999).In the subgroup analysis,the sensitivity of combining CKMB and c-c Tn increased with time from symptom onset<6 h compared with c-c Tn alone(72.8%vs.75.0%,P=0.046),while the sensitivity did not increase with time from symptom onset>6 h(97.5%vs.98.3%,P=0.317).The AUC of the combination of CK-MB and POC-c Tn significantly increased compared to the single POC-c Tn assay(0.776 vs.0.750,P=0.002).The AUC of the combined CKMB and c-c Tn/hs-c Tn assays did not significantly decrease compared with that of the single c-c Tn/hs-c Tn assays within 6 h.CONCLUSIONS:The combination of CK-MB and POC-c Tn or c-c Tn may be valuable for the early diagnosis of AMI,especially when hs-c Tn is not available.
基金financially supported by the National Key R&D Program of China(2017YFA0204700)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(2020GXLH-Z-021)+1 种基金the China-Sweden Joint Mobility Project(51811530018)the Fundamental Research Funds for the Central Universities.
文摘Convenient,rapid,and accurate detection of cardiac troponin I(cTnI)is crucial in early diagnosis of acute myocardial infarction(AMI).A paper-based electrochemical immunosensor is a promising choice in this field,because of the flexibility,porosity,and cost-efficacy of the paper.However,paper is poor in electronic conductivity and surface functionality.Herein,we report a paper-based electrochemical immunosensor for the label-free detection of cTnI with the working electrode modified by MXene(Ti_(3)C_(2))nanosheets.In order to immobilize the bio-receptor(anti-cTnI)on the MXene-modified working electrode,the MXene nanosheets were functionalized by aminosilane,and the functionalized MXene was immobilized onto the surface of the working electrode through Nafion.The large surface area of the MXene nanosheets facilitates the immobilization of antibodies,and the excellent conductivity facilitates the electron transfer between the electrochemical species and the underlying electrode surface.As a result,the paper-based immunosensor could detect cTnI within a wide range of 5-100 ng/mL with a detection limit of 0.58 ng/mL.The immunosensor also shows outstanding selectivity and good repeatability.Our MXene-modified paper-based electrochemical immunosensor enables fast and sensitive detection of cTnI,which may be used in real-time and cost-efficient monitoring of AMI diseases in clinics.
基金supported by resources provided by the North Florida/South Georgia Veterans Health System,Gainesville,FL
文摘Background:Cardiac troponin assays have improved the ability to detect myocardial damage.However,ascertaining whether troponin elevation is due to myocardial infarction(MI) or secondary to another process can be challenging.Our aim is to evaluate provider-level variation in the diagnosis of MI and the use of invasive coronary angiography(ICA) among patients with undifferentiated elevations in cardiac troponin.Methods:We analyzed data from all patients with elevated troponin levels in a single Veterans Affairs(VA) Medical Center between 2006 and 2007.One of several cardiologists prospectively evaluated each patient's presentation and course of care.We compared the frequency of MI diagnosis and ICA use between physicians using univariate odds ratios(OR).Results:Among 761 patients,34.0% were diagnosed with MI and 25.9% underwent ICA.The unadjusted rates of MI(23.9% to 56.7%,P=0.02) and ICA(17.3% to 73.3%,P<0.001) differed between physicians.Comparing the patient cohorts for each physician,baseline characteristics were similar except for chest pain.In multivariate regression,factors associated with the use of cardiac ICA included an abnormal electrocardiograph(ECG)(OR=1.89,P=0.014),level of troponin(OR=1.71,P=0.004),chest pain(OR=8.60,P<0.001),and care by non-VA physicians(OR=4.45,P=0.006).One physician had a lower ICA use(OR=0.56,P=0.017).In multivariate regression of MI,no physician-level variation was observed.Conclusion:Among patients with elevated troponin,the likelihood of being diagnosed with MI and undergoing ICA is dependent on their clinical presentation.After adjustment,physician-level variation in care was observed for the use of ICA,but not for the diagnosis of MI.
文摘AIM: To identify the typical shape of the rise and fall curve of troponin(Tn) following the different types of myocardial infarction(MI). METHODS: We conducted a systematic search in PubM ed and Embase including all studies which focused on the kinetics of Tn in MI type 1, type 4 and type 5. Tn levels were standardized using the 99 th percentile, a pooled mean with 95%CI was calculated from the weighted means for each time point until 72 h. RESULTS: A total of 34 of the 2528 studies identified in the systematic search were included. The maximum peak level of the Tn was seen after 6 h after successful reperfusion of an acute MI, after 12 h for type 1 MI and after 72 h for type 5 MI. In type 1 MI there were additional smaller peaks at 1 h and at 24 h. After successful reperfusion of an acute MI there was a second peak at 24 h. There was not enough data available to analyze the Tn release after MI associated with percutaneous coronary intervention(type 4).CONCLUSION: The typical rise and fall of Tn is different for type 1 MI, successful reperfusion of an acute MI and type 5 MI, with different timing of the peak levels and different slopes of the fall phase.
文摘BACKGROUND Evaluation of suspected stable angina patients with probable coronary artery disease(CAD)in the community is challenging.In the United Kingdom,patients with suspected stable angina are referred by community physicians to be assessed by specialists within the hospital system in rapid access chest pain clinics(RACPC).The role of a highly sensitive troponin I(uscTnI)assay in the diagnosis of suspected CAD in a RACPC in a“real-life”setting in a non-academic hospital has not been explored.AIM To examine the diagnostic value of uscTnI(detection limit 0.12 ng/L,upper reference range 8.15 ng/L,and detected uscTnI in 96.8%of the reference population),in the evaluation of stable CAD in a non-selected patient group,with several co-morbidities,who presented to the RACPC.METHODS One hundred and seventy two RACPC patients were assigned to either functional or anatomical testing according to the hospital protocol.RESULTS The investigations offered to patients were exercise tolerance test 7.6%,24 h ECG 1.2%,Echocardiogram 14.5%,stress echocardiogram 8.1%,coronary computed tomography angiography(CCTA)12.8%,coronary angiogram 13.4%,17.4%were diagnosed with non-cardiac chest pain,3.5%treated as stable angina,8.2%reviewed by cardiologists,electronic medical records were not available in 10.4%.Receiver operating characteristic curves for CAD used uscTnI values measured in patients who underwent functional testing,angiogram or CCTA.Values>0.52 ng/L showed 100%sensitivity and at>11.6 ng/L showed 100%specificity.In the range>0.52-11.6 ng/L,uscTnI may not have the same diagnostic potential.In patients assigned to coronary angiogram higher concentrations of uscTnI was associated with severe CAD.Low levels of uscTnI and low pre-test probability of CAD(QRISK3)may decrease patient numbers assigned to CCTA.CONCLUSION The uscTnI diagnostic cut-off values in a RACPC will depend on patient population and their presenting co-morbidity.In the presence of clinical comorbidities and previous CAD the uscTnI needs to be used in conjunction with clinical assessment.
基金Supported by Confederation of Epidemiological Associations registered under Govt of Kerala.Grant No.30-955/2012 CEA
文摘Objective:To study the usefulness of traditional lipid profile levels in screening subjects who had developed chest pain due lo cardiac event as indicated by a positive troponin I test.Methods:In this retrospective study data of ihe 430 patients presented lo the emergency department with symptoms of cardiac ischemia who underwent both troponin and lipid profiles tests were compared with the lipid profiles of 165 normal healthy subjects(controls).The troponin was detected qualitatively when a specimen contains troponin I(cTnI)above the 99th percentile(TnI>0.5 ng/mL).The total cholesterol,high density lipoproteins cholesterol,very low density lipoproteins and Iriacvl glycerol levels were also analyzed and Ion densilv lipoprotein level was calculated using Friedewald's formula.Results:Patients with chest pain and positive troponin test(with confirmed cardiac event)were found lo have significantly elevated levels of total cholesterol,triacyl glycerol levels,low density lipoprotein level and significantly reduced high densilv lipoproteins cholesterol levels when compared lo the patients who experienced only chesl pain(negative troponin)and healthy controls.Conclusions:Traditional lipid profile levels is still can be used in screening popiilalions lo identify the subjecis with high risk of developing cardiacevent in case if the laboratory set up has not troponin test facilities.
文摘BACKGROUND Release of cardiac biomarkers is common after strenuous endurance exercise,but data on intermittent exercise are scarce.It has not been investigated whether cardiac troponin elevation is influenced depending on the type of exercise that an athlete is adapted to perform.We hypothesized that intermittent but not continuous exercise induces cardiac troponin elevation in professional athletes adapted to high-intensity intermittent exercise.AIM To examine how training specificity impacts high-sensitivity cardiac troponin T(hs-cTnT)release.METHODS Nine professional floorball players participated in the study,which comprised two different exercise tests:a continuous incremental cycle ergometer test and a Yo-Yo Intermittent Recovery 2(Yo-Yo IR2)test.Serial assessment of hs-cTnT was performed after the cycle ergometer test and the Yo-Yo IR2 test(baseline,0,2,6,and 24 h).RESULTS No hs-cTnT elevation above the myocardial damage cutoff(≥14 ng/L)was shown after the cycle ergometer test,whereas hs-cTnT levels rose over the cutoff in three of nine participants after the Yo-Yo IR2 test.The hs-cTnT levels peaked at 6 h after both tests,but were significantly higher after the Yo-Yo IR2 test compared to the cycle ergometer test(median hs-cTnT concentration 10.6 ng/L vs 7.8 ng/L,P=0.038).All levels returned to baseline within 24 h.CONCLUSION In professional athletes adapted to high-intensity intermittent exercise,hs-cTnT was significantly elevated after intermittent but not continuous exercise.This principle of specificity training should be considered when designing future studies to avoid misinterpretation of hs-cTnT elevation.
文摘Troponin is a complex of three proteins (troponin I, troponin C, and troponin T) that binds Ca2+ and is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of troponin I (TnI) in vertebrates has been extensively characterized, but its role in molluscan muscles has not yet been elucidated. Our previous work suggested that the troponin C subunit has a role in adductor phasic muscle but not in catch muscle. Here, we investigated the molecular characteristics of TnI from the bivalve Japanese pearl oyster, Pinctada fucata to aid the elucidation of the function of molluscan muscle troponin. We determined the primary structure of the full-length TnI protein from the P. fucata adductor muscle (Pifuc-TnI) and found that it is composed of 286 amino acid residues with a predicted molecular weight of 33,737. Motif structure predictions and multiple sequence alignments revealed that Pifuc-TnI has a 138 residue extension at its N-terminus compared with rabbit TnI. This is analogous to characterized TnIs from other mollusks. However, unlike scallop TnI, Pifuc-TnI is predicted to contain two cAMP-dependent protein kinase phosphorylation sites, at residues 39 - 45 (RRGTEDD) and 145 - 151 (KKKSKRK). Phylogenetic analysis indicated that Pifuc-TnI and molluscan TnIs were grouped into the same clade. Pifuc-TnI gene structure predictions using Splign alignment of our obtained cDNA and genome sequences indicated that Pifuc-TnI consists of fifteen exons, with the start and stop codons located in exon 2 and exon 11, respectively. Using quantitative real-time PCR, we determined that the Pifuc-TnI gene is predominantly expressed in adductor phasic muscle, weakly in adductor catch muscle, and is not expressed in the gill, mantle or foot. These findings suggest that TnI, as a component of the troponin complex, plays a regulatory role in adductor phasic muscle contraction, but not in catch contraction.
基金Supported by the National Key Scientific Instrument and Equipment Development Projects of China(2012YQ04014005)。
文摘Acute myocardial infarction(AMI)is a major health problem leading to high rates of mortality and morbidity.Biomarker cardiac troponin I(cTnI)has shown high sensitivity and specificity towards AMI detection,and has been regarded as"gold standard".An ultrasensitive method to detectcTnI with low concentration in human fluid is essential.In this paper,we developed an aptamer-based assay coupled with rolling circle amplification(RCA)and molecular beacon probe for sensitive detection ofcTnI.In this strategy,aptamer acts as a bridge to communicate between oligonucleotides andcTnI.RCA reaction produces a single-stranded tandem repeated copy of the circular template,which are recognized by fluorescence molecular beacon probe.With this strategy,highly sensitive and specific detection of cTnI was realized with the lowest detectable concentration of 7.24 pg/m L.The developed aptamer-RCA assay can be a promising tool in clinical samples analysis.The assay can also analyze other disease-related biomarkers by replacing the aptamer.
文摘Troponin C (TnC) is one of the subunits of troponin. Troponin, which is activated by Ca2+ binding, is a thin filament-associated regulator of vertebrate striated muscle contraction. The function of TnC in vertebrates has been characterized in detail, but the role of TnC in molluscan muscles is still unclear. In this work, we investigated whether TnC plays a role in the catch contraction of molluscan smooth muscle in the bivalve Japanese pearl oyster Pinctada fucata. We determined the full-length primary structure of the TnC protein from the P. fucata adductor muscle (Pifuc-TnC), and found it is composed of 150 amino acid residues with a predicted molecular weight of 17,400. Multiple sequence alignments indicated that it had four EF-hand motifs, but only one (site IV) was predicted to have Ca2+-binding ability. This is analogous to characterized TnCs from other mollusks. Three-dimensional modeling of Pifuc-TnC using SWISS-MODEL indicated the presence of a short loop within the α-helix connecting the site II and III EF-hand motifs. We predicted the gene structure of Pifuc-TnC using Splign alignment of our obtained cDNA and genome sequences and elucidated that Pifuc-TnC consists of five exons, with the start and stop codons located in exon 1 and exon 5, respectively. Using quantitative real-time PCR, we determined that the Pifuc-TnC gene is predominantly expressed in adductor phasic muscle and rarely in adductor catch muscle, gill, mantle and foot. These findings suggest that TnC may not have a role in catch muscle contraction.
