As a necessary diagnostic criteria for acute myocardial infarction ,the sensitivity of cardiac troponin is of great significance in clinical diagnosis and treatment .Commercial kits also experienced several generations , and gradually entered the era of high sensitivity . High sensitivity era has brought us opportunities and challenges , the higher sensitivity greatly promotes the efficiency of early diagnosis , highlights the risk assessment and prognostic value , but it also leads to the reduction of diagnostic specificity, we must understand the application features so we can meet the challenges better .In this article we elaborated the application value of high-sensitivity troponin and some matters needing attention .

Objective To analyze the relation between glycosylated hemoglobin (HbA1c) and coronary heart disease (CHD) among diabetic and non-diabetic individuals.Methods A total of 1190 in patients from January 2009 to September 2009 were selected and divided into two groups:225 patients with diabete mellitus and 965 patients without.We collected the age,sex,triglyceride ( TG),total cholesterol ( CHO),high-density lipoprotein ( HDL-C),low-density lipoprotein ( LDL-C),fasting blood-glucose (FBG),glycosylated hemoglobin (HbA1c),high-sensitivity CRP (hs-CRP) and analyzed the relation between these indexes and CHD in diabetic and non-diabetic individuals respectively,then,analyzed the difference of HbA1c between patients with and without CHD after correcting the differentiating factor with a multivariable-adjusted model.Meanwhile,according the HbA1c level,we divided all participants into four groups:4.0％ -5.4％( Ⅰ),5.5％ -5.9％ ( Ⅱ),6.0％ -6.4％ ( Ⅲ),≥6.5％ ( Ⅳ),and observed the distribution of HbA1c and coronary heart disease in diabetic and non-diabetic individuals respectively.Results ( 1) In non-diabetic individuals,statistically significant difference of male( 80.5％ υs 62.7％),age [ ( 59 ±11) years υs (55 ± 11) years],FBG [(5.62 ± 1.48) mmol/L υs (5.30 ±0.84) mmol/L],HbA1c [(5.98±0.92)％ υs (5.65 ±0.53)％],CHO [(4.48 ±1.01) mmol/L υs (4.77 ±1.04) mmol/L],LDL-C [(2.59±0.87) mmol/L υs (2.79 ±0.86) mmol/L],HDL-C [(1.08 ±0.26) mmol/L υs(1.21 ±0.32) mmol/L] was observed between patients with and without CHD (P ＜0.01),however,in diabetic individuals,only LDL-C [ ( 2.56 ± 0.81) mmol/L υs ( 3.07 ± 0.90) mmol/L],CHO [ (4.44 ±0.95) mmol/L υs ( 5.08 ± 1.16) mmol/L] were observed ( P ＜ 0.0 1).(2) In all participants,the higher of HbA1c,the higher of CHD percent,compared to patients without CHD,the percent of high HbA1c in CHD patients was significantly higher.After adjusting for age,sex,HDL-C,HbA1c was an independent risk marker for CHD in non-diabetic individuals ( OR:1.935,95％ CI:1.356 - 2.762,P ＜ 0.05),however,links between FBG in the non-diabetic range and CHD appeared weaker after controlling indexes listed above( OR:1.507,95％CI:1.082 -2.098,P＜0.05).Conclusion HbA1c is an independent risk factor for CHD in nondiabetic individuals and prior to FBG.

Objective To investigate plasma levels of high-sensitivity C-reactive protein (hs-CRP) in patients with coronary heart disease (CHD) and relationship between hs-CRP levels and cardiac function. Methods The serum hs-CRP concentrations in 894 CHD patients diagnosed by coronary angiography and 141 healthy controls were measured by particle enhanced immunoturbidimetric assay. Results The median of hs-CRP levels was 1.70 (0.13-19.53 ) mg/L and abnormal ratio was 37.6% (336/894), that were significantly higher in CHD group than healthy controls [0. 99(0. 13-19. 53) rag/L, 7. 1% (10/141) ] (Z=-6. 476,X<'2> = 50. 882, P <0.01 ). The median of hs-CRP levels was 5.35 (0. 18-19. 10) mg/L and abnormal ratio was 63.9% (92/144), that were much higher in acute myocardial infarction (AMI) group than in old myocardial infarction (OMI) group [2.27 (0.13-19.19) mg/L, 43.7% (129/295) ] (Z = -3.353 ,X<'2> = 15. 732, P <0. 01 ). The median of hs-CRP levels was 1.45 (0.19-19.53) mg/L in unstable angina pectoris(UAP) group and abnormal ratio was 29.1% (73/251), that were was higher in stable angina pectoris (SAP) group [1.04 (0.13-16.31 ) mg/L, 20. 6% (42/204) ] (Z=-2.981, P = 0.003;X<'2> = 4.30, P=0.038 ) . Furthermore, Kruskal-Wallis test showed the concentrations of hs-CRP and NT-proBNP was increased along with increment of CHD severity (NYHA functional classification) (X<'2> = 120.185,424.945, P <0.001 ). Multivariate analysis showed that hs-CRP levels positively correlated with NYHA functional classification ( r = 0.328, P <0.01 ) as well as NT-proBNP levels (r=0.413, P <0.01 ). Conclusion Serum hs-CRP level increases along with CHD severity, indicating that hs-CRP may play a certain role in the occurrence and development of CHD.

Objective: To evaluate chemiluminescence immunoassay (CLIA) for detecting blood levels of aldosterone and rennin with its diagnostic value of primary aldosteronism (PA) with comparison to radio immunoassay (RIA). Methods: According to American protocols of CLSI, we conducted a veriifcation study between RIA and CLIA for their precision, accuracy, linearity and reference ranges; meanwhile, taking clinical diagnosis as golden standard, examined renin activity or concentration and aldosterone concentration in 20 healthy volunteers and 40 hypertension patients by both RIA and CLIA, compared the ratios of ARR (aldosterone concentration/renin activity) or ADRR (aldosterone concentration/renin concentration) for the speciifcity and sensitivity of PA diagnosis. Results: Within-lot and between-lot accuracies of CLIA for detecting aldosterone levels were below 5% and 10%, the recoveries were 102% and 95% respectively. There was a good linear correlation in the range of aldosterone at (3-74) ng/dl and renin at (0.99-330) μIU/ml. In healthy volunteers, renin level was higher in 2 subjects, while aldosterone level and ADRR ratio were within normal references in all subjects by the manufacturer. In hypertension patients, the sensitivity and speciifcity for aldosterone and rennin detections by CLIA were at 85.7% and 97.0%, by RIA were at 85.7% and 94.0%. Conclusion: CLIA has the superiority of simple performance, repeatable and without radioactive contamination; it is recommended for replacing RIA as necessity.

Objective To evaluate the utility of MMP9,MPO and sCD40L in detection of the character of coronary artery plaque.Methods From April 2008 to January 2010,118 patients from outpatient of Fu Wai Hospital with chest pain were enrolled.All of them underwent 64 Multiple-detector row spiral computer tomography (64-MDCT),the CT value ＜ 130 Hu patients were enrolled in non-calcified plaque group (71 cases),CT value ≥ 130 Hu patients were enrolled in the calcified plaque group (47 cases).Ninty healthy volunteers were selected as the control group.Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of serum markers,including MMP9,MPO and sCD40L.Levels of MMP9,MPO and sCD40L of each group were compared.ROC curve was used to evaluate the sensitivity and specificity of the markers in diagnosis of non-calcified plaque.Results MMP9,MPO and sCD40L levels of non-calcified were ( 762.25 ± 368.71 ),[ 844.10 (582.00 - 1220.70) ],(9.37 ± 3.15) μg/L,higher than the healthy control group (342.70 ± 178.53),[426.35 ( 283.20 - 592.00) ],(6.55 ± 2.96) μg/L and calcified plaque group ( 483.12 ± 219.09 ),[ 469.00 ( 302.45 - 723.55) ],( 7.24 ± 2.86) μg/L The difference was statistically significant ( F =42.47,H =50.28,F =17.94,all P ＜ 0.01 ). Areas of MMP9,MPO and sCD40L under the ROC curve to predict non-calcified plaque were 0.854,0.792,0.751 respectively,when the identification threshold for non-calcified plaque were 510.13,537.82,7.05 μg/L respectively,the diagnostic sensitivity was 80％,80％,80％ respectively,and specificity was 80％,67％ and 55％ respectively.Conclusion The serum MMP9,MPO and sCD40L levels can help to determine the　character of coronary plaque.

Objective To validate the analytical performance of a cardiac troponin I(cTnI)assay AccuTnI+3 on chemiluminescnet analyzer DXI800 and Access2;and to establish the 99th percentile of cTnI in an apparently healthy Chinese population.Methods The subjects are composed of 1 369 apparently healthy people and 20 acute myocardial infarction(AMI)patients from Wuhan Asian Heart Hospital and Fuwai Hospital from October 2014 to June 2015.The healthy people include 680 males and 689 females;with 340 subjects aged 18-30,674 subjects aged 31-64, and 355 subjects aged ≥65.The detection limits and imprecision of AccuTnI +3 assays were validated according to CLSI EP 15-A2 and EP17-A2 documents;the same samples were analyzed on DXI800 and Access2 to assess the consistency between the two analyzers using Bland Altman plot and Passing-Bablok regression.The correlation between different sample types (lithium heparin plasma, EDTA plasma & serum)were assessed using linear regression analysis.The lithium heparin plasmasamples from 1 369 apparently healthy people were analyzed to calculate the 99th percentile of cTnI.The cTnI concentrations were compared among age and sex groups.The 99th percentile of cTnI were also calculated for each group.The detection rate of cTnI in apparently healthy people was calculated using SPSS23.0.Results The limit of blank(LoB), limit of detection(LoD), and limit of quantification(LoQ)where CV%=10% were 0.007 ng/ml,0.010 ng/ml and 0.016 ng/ml on DXI800;0.008 ng/ml,0.012 ng/ml and 0.026 ng/ml on Access2,respectively.The cTnI measurements on DXI800 and Access2 were consistent and comparable.The cTnI concentrations of lithium heparin plasma, EDTA plasma and serum samples were linearly correlated pairwise: EDTA plasma measuremen t =0.76 heparin plasma measurement, R2=0.999(n=40, P<0.001); serum measuremen t =1.05 heparin plasma measurement,R2=0.996(n=40,P<0.001); serum measuremen t=1.38 EDTA plasma measurement, R2=0.993(n=40,P<0.001).The 99th percentiles were 0.030 ng/ml and 0.035 ng/ml on DXI800 and Access2,respectively,from 1 369 apparently healthy Chinese people.cTnI is significantly higher in elder group than in younger group.The 99th percentiles in 18-30 years old group,31-64 years old group,and≥65 years old group are:0.011 ng/ml,0.029 ng/ml,and 0.035 ng/ml respectively for DXI800;0.023 ng/ml,0.034 ng/ml, and 0.045 ng/ml respectively for Access2.cTnI is significantly higher in men than in women.The 99th percentiles in men and women are: 0.034 ng/ml and 0.032 ng/ml respectively for DXI800;0.043 ng/ml and 0.031 ng/ml respectively for Access2.cTnI was measurable in 62%and 87%of healthy subjects on DXI800 and Access2 systems,respectively.Conclusions The analytical performance of AccuTnI+3 assay fulfills the need of clinical use and the criteria of high-sensitive cardiac troponin assay.