Performance Evaluation of STRATUS CS200 for Cardiac Markers

The STRATUS CS200 (Siemens Healthcare Diagnostics Inc., USA) has recently been developed as an on-site diagnostic instrument for assaying several kinds of cardiac markers within a short duration. The precision, linearity, comparison, limit of quantification, and turnaround time (TAT) were evaluated for troponin I, creatine kinase-MB (CK-MB), N-terminal pro-brain natriuretic peptide (NT-proBNP), and myoglobin assays according to guidelines provided by the Clinical and Laboratory Standards Institute. The total coefficients of variation of the four items were between 1.90% and 4.25%. All markers showed a linearity that was ≥0.99, and the values were within the manufacturer's range. All items showed a close correlation with E170 (Roche Diagnostics, Germany). The limits of quantification for troponin I, CK-MB, myoglobin, and NT-proBNP were 0.03 ng/mL, 0.3 ng/mL, 1 ng/mL, and 15 pg/mL, respectively. The TAT was 14 minutes. The performance of the STRATUS CS200 for assaying cardiac markers was highly satisfactory in terms of the precision, linearity, limit of quantification, and TAT, and it showed a good correlation with the comparative method.

Annual Report on the External Quality Assessment Scheme for Immunoassay Tests in Korea (2015)

Two trials of external quality assessment were performed in 2015, with 13 test items grouped into four test categories. The first trial materials were sent on May 19, 2015 and the second trial was performed on November 9, 2015 with 13 items including tumor markers, thyroid hormones, cardiac marker troponin (troponin T or troponin I), and procalcitonin (PCT) as biomarkers by immunoassay methods. The bone marker, carboxy-terminal collagen crosslinks (CTX) was replaced by procalcitonin since 2014, because a limited number of institutions performed assays with CTX. External quality surveys of 13 immunoassay test items with 16 control materials were conducted, as scheduled. In total, 13 control materials were used, which consisted of six tumor markers, namely alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carcinoma antigen (CA) 125, carbohydrate antigen (CA) 19-9, human chorionic gonadotrophin (HCG), and prostate specific antigen (PSA). In addition to tumor markers, 5 thyroid markers, namely thyroid hormone (T)3, T4, thyroid stimulating hormone (TSH), free T4, and thyroglobulin (TG) were included. Furthermore, troponin, as a cardiac marker, and procalcitonin, as a new biomarker, have been adopted since 2014. Five home-made pooled sera and 3 commercial control sera were used as survey materials. MAS Tri-point Liquimmune level 3 (Medical Analysis Systems Inc., USA) was used for thyroid hormones. Procalcitonin and troponin control materials were from Elecsys Precis Control Varia and Elecsys Precis Control Troponin (Roche, Germany), respectively. The number of laboratories participating in the external quality assessment for Immunoassay Subcommittee was 719 institutions in the first trial survey (response rate 98.7%) and 730 institutions in the second survey (94.9%). The test items most frequently used in immunoassays were TSH (93.2%, 93.1%), free T4 (90.3%, 90.2%), and AFP (89.4%, 89.0%), whereas recently adopted biomarkers were less frequently used: troponin I (36.6%, 37.1%), procalcitonin (24.1%, 26.7%), and thyroglobulin (10.3%, 10.7%). The quality of the laboratories participating in the survey seems to be continuously improving, according to their peer group results.

Annual Report on External Quality Assessment Scheme for Immunoassay Tests in Korea (2014)

In 2014, two external quality assessment trials were performed on 13 test items grouped in four categories. The laboratories procured the materials for the first and second trials on 13 May 2014 and 11 November 2014, respectively. The trials were performed on 13 test items, including tumour markers, thyroid hormones, cardiac marker troponin (troponin T or troponin I), and procalcitonin as a new biomarker for immunoassay methods. The bone marker carboxy-terminal collagen crosslinks (CTX) has been replaced by procalcitonin this year because only a limited number of institutions used it. External quality surveys of the 13 immunoassay test items with 8 control materials were performed as scheduled. The 13 control materials included six tumour markers, alpha-fetoprotein, carcinoembryonic antigen, carcinoma antigen 125, carbohydrate antigen 19-9, human chorionic gonadotrophin, and prostate specific antigen, as well as five thyroid markers, thyroid hormone 3 (T3), T4, thyroid stimulating hormone, free T4, and thyroglobulin. This year, procalcitonin has been introduced as a new biomarker in addition to troponin, which was introduced last year. Five homemade pooled sera and three commercial control sera were used as survey materials. The MAS Tri-point Liquimmune level 3 (Medical Analysis Systems Inc., USA) was used for controls of thyroid hormones, while Elecsys PreciControl Varia and Elecsys PreciControl Troponin (Roche, Germany) were used for controls of the new biomarkers procalcitonin and troponin, respectively. In the external quality assessment by the Immunoassay Subcommittee, 712 institutions participated in the first trial survey (response rate 97.9%), while 715 participated in the second survey (response rate 97.9%). The quality of the participating laboratories seems to be continuously improving compared to the results of their peers. Additionally, this year procalcitonin has been introduced as a new biomarker instead of the CTX, which was used in 2013, while thyroglobulin and troponin-T/troponin-I, which were used for the 2013 samples, continue to be used in surveys by the Immunoassay Subcommittee.

Intravenous human umbilical cord blood improves elctrophysiological and metabolic properties in ISO induced myocardial necrosis in rats.

Rats treated with isoproterenol (ISO, 85 mg/kg, sc, twice at an interval of 24 h) showed a significant increase in heart rate, mean arterial blood pressure, pressure rate index, ST elevation on ECG, and a significant increase in the levels of cardiac marker enzymes- lactate dehydrogenase, and creatine kinase in serum and a significant reduction in superoxide dismutase, and catalase and increase in thiobarbituric acid reactive substance activity in heart tissue. Treatment with Human umbilical cord blood (hUCBC; 500 and 1000 µL, iv, via the tail vein; 2 h after the second dose of ISO) significantly restored back to normal levels and showed a lesser degree of cellular infiltration and infarct size in histopathological and planimetry studies respectively. Thus, hUCBC ameliorates cardiotoxic effects of isoproterenol and may be of value in the treatment of myocardial infarction.

Relationship between the cardiac markers in ST-segment elevation myocardial infarction and quality of life six months later / 中国医师进修杂志

Objective To study the relationship between the cardiac markers in ST-segment elevation myocardial infarction (STEMI) and quality of life (QOL) six months later.Methods N-terminal pro-B-type natriuretic peptide (NT-proBNP),cardiac troponin I (cTnI),creatine kinase isoenzyme-MB (CK-MB)and myoglobin(Myo) was tested in 76 patients with STEMI on admission(0 h) and 24 h after admission.QOL six months later was evaluated by using the SF-36 health survey questionnaire.The relationship between the cardiac markers and QOL was analyzed by multivariate linear regression analysis.Results The total SF-36 scores and the scores of physical function,body pain and general health showed negative linear correlation with NT-proBNP on admission (0 h) and 24 h after admission (P ＜ 0.05).The total SF-36 scores and the scores of physical function and body pain showed negative linear correlation with cTnI on admission (0 h)and 24 h after admission (P ＜ 0.05).The total SF-36 scores and the scores of body pain showed negative linear correlation with CK-MB on 24 h after admission (P ＜ 0.05).The scores of vitality showed negative linear correlation with Myo on admission (0 h) (P ＜ 0.05).Conclusion The higher levels of NT-proBNP,cTnl and CK-MB indicate the lower QOL six months later.

Effect of detection of cardiac markers on patients with acute coronary syndrome / 中国实用护理杂志

Objective To investigate changes in cardiac markers and its effect on instructing nursing of patients with acute coronary syndrome(ACS).Methods 100 ACS patients from cardiology department and CCU were randomly divided into the observation group and the control group. The control group was given routine care. the observation group was given intervention according to positive results of cardiac markers. Some indexes such as B-type natriuretic peptide, myoglobin, creatine kinase isoenzyme, cardiac troponin I, and EKG, congestive heart failure and cardiogenic shock as well as appraisal of patients and relatives to nurses were compared between the two groups. Results The observation group was better than the control group in subsequent indicators: B-type natriuretic peptide, myoglobin, creatine kinase isoenzyme, cardiac troponin I,EKG, congestive heart failure and cardiogenic shock, and appraisal of patients and relatives to nurses was also better than the control group. Conclusions Detection of cardiac markers not only has significance for diagnosis, risk stratification and prognosis of ACS, but also help to instruct nursing of ACS patients. It has an important role in raising the nurses ability to identify risk factors and take effective measures to reduce complications and mortality, improve satisfaction degree of patients and their family members.