Troponin T STAT (Short Turn Around Time), CARDIAC T

Catalog Number: 04660307190

INTENDED USE

Immunoassay for the in vitro quantitative determination of troponin T in human serum and plasma. This assay can be used as an aid in the differential diagnosis of acute coronary syndrome to identify necrosis, e.g. acute myocardial infarction. The test is further indicated for the risk stratification of patients presenting with acute coronary syndrome and for cardiac risk in patients with chronic renal failure. The test may also be useful for the selection of more intensive therapy and intervention in patients with elevated levels of cardiac troponin T.

The electrochemiluminescence immunoassay “ECLIA” is intended for use on Elecsys and cobas e immunoassay analyzers.

STORAGE AND STABILITY

Stability:
unopened at 2-8 °C up to the stated expiration date
after opening at 2-8 °C 12 weeks
on the analyzers 8 weeks

Store at 2-8 °C.

Do not freeze.

Store the Elecsys reagent kit upright in order to ensure complete availability of the microparticles during automatic mixing prior to use.

CALIBRATION

Traceability: The Troponin T STAT assay (4th generation, 04660307) has been standardized against the Troponin T STAT assay (3rd generation, 12017423). This in turn was originally standardized against the Enzymun-Test Troponin T (CARDIAC T) method.

Every Elecsys reagent set has a barcoded label containing specific information for calibration of the particular reagent lot. The predefined master curve is adapted to the analyzer using the relevant CalSet.

Calibration frequency: Calibration must be performed once per reagent lot using fresh reagent (i.e. not more than 24 hours since the reagent kit was registered on the analyzer).

Renewed calibration is recommended as follows:

LIMITS AND RANGES

Measuring range

0.010-25.00 µg/L or ng/mL (defined by the lower detection limit and the maximum of the master curve). Values below the lower detection limit are reported as < 0.010 µg/L (ng/mL). Values above the measuring range are reported as > 25.00 µg/L or ng/mL (or up to 250 µg/L or ng/mL for 10-fold diluted samples).

Lower limits of measurement

Lower detection limit of the test

Lower detection limit: 0.010 µg/L (ng/mL)

The lower detection limit represents the lowest measurable analyte level that can be distinguished from zero. It is calculated as the value lying three standard deviations above that of the lowest standard (master calibrator, standard 1 + 3 SD, repeatability study, n = 21).

³ 0.03 µg/L (ng/mL) is the troponin T concentration, which is read off from the trendline, that can be reproducibly measured with the intermediate precision CV of 10 %.

When taking lot to lot variability into consideration, at 0.030 ng/mL a CV of 18 % is achieved and at 0.060 ng/mL a CV of 10 % is achieved.

SPECIFIC PERFORMANCE DATA

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

PRECISION

Precision was determined using Elecsys reagents, pooled human sera and controls in a modified protocol (EP5-A) of the CLSI (Clinical and Laboratory Standards Institute): 6 times daily for 10 days (n = 60). The following results were obtained:

Precision was determined using Elecsys reagents, pooled human sera and controls in a separate study according to protocol EP5-A2 of the CLSI (Clinical and Laboratory Standards Institute): 2 runs per day in duplication each for 21 days (n = 84). The following results were obtained:

Elecsys 2010 and cobas e 411 analyzers
Repeatability Intermediate precision
Sample Mean SD CV SD CV
µg/L µg/L % µg/L %
(ng/mL) (ng/mL) (ng/mL)
Human serum 1 0.047 0.002 4.5 0.003 6.2
Human serum 2 0.652 0.013 2.0 0.030 4.6
Human serum 3 6.09 0.177 2.9 0.343 5.6
PreciControl TNT1 0.137 0.003 2.2 0.005 3.5
PreciControl TNT2 2.89 0.071 2.5 0.136 4.7

cobas e 601 and cobas e 602 analyzers
Repeatability Intermediate precision
Sample Mean SD CV SD CV
µg/L µg/L % µg/L %
(ng/mL) (ng/mL) (ng/mL)
Human serum 1 0.017 0.003 15.7 0.003 16.6
Human serum 2 0.020 0.002 11.4 0.002 12.2
Human serum 3 0.081 0.002 2.7 0.003 3.7
Human serum 4 0.118 0.003 2.7 0.004 3.3
Human serum 5 0.470 0.009 1.9 0.014 3.0
Human serum 6 2.89 0.060 2.1 0.091 3.1
Human serum 7 24.2 0.449 1.9 0.668 2.8
PreciControl TNT1 0.066 0.002 3.1 0.003 4.1
PreciControl TNT2 2.15 0.028 1.3 0.049 2.3

METHOD COMPARISON

A comparison of Elecsys Troponin T STAT assay (3rd generation; x) with Elecsys Troponin T STAT assay (4th generation; y) using clinical samples gave the following correlations:

Number of samples measured: 60

The sample concentrations were between approx. 0.08 and 18.5 µg/L (ng/mL).

Passing/Bablok48 Linear regression
y = 1.012x - 0.017 y = 1.03x - 0.03
t = 0.985 r = 1.000

ANALYTICAL SPECIFICITY

For the monoclonal antibodies used, the following cross-reactivities were found:

h-skeletal muscle troponin T 0.001 %, h-cardiac troponin I 0.002 %, h-skeletal muscle tropomyosin 0.001 %, h-cardiac tropomyosin 0.1 %, and h-cardiac myosin light chain 1 0.003 %.