3%) had elevations of both markers, whereas the remaining 2 patients had elevations of cTnI
or cTnT alone.
Clinical assays for cardiac troponins are sandwich immunoassays directed to stable portions of cardiac cTnI
The ACPP now in use at our hospital uses medical history, ECG, and biomarkers CK-MB, total CK, myoglobin, and cTnI
to rule ACS in or out in a 9-hour algorithm.
More information on the high sensitivity Acute Care cTnI
is available at www.
and cTnT assays have replaced creatine kinase (CK) MB because of their myocardial tissue specificity (1, 10).
Although it is believed that cTnI
in the blood of AMI patients is mainly present in the form of binary cardiac troponin complex (I-C) (14, 15), most studies have used I--T--C to demonstrate the negative interference ofTnAAbs with the cTnI
assays (4, 7, 10).
Following institutional review board approval, we prospectively included consecutive, unselected patients presenting from February 4, 2014, through May 9, 2014, in whom initial preset serial cTnI
measurements at 0, 3, 6, and 9 h were ordered on clinical indication at Hennepin County Medical Center (Minneapolis, MN) to rule in and rule out AMI [Use of Abbott High Sensitivity Troponin I Assay In Acute Coronary Syndromes (UTROPIA); NCT02060760].
Patients were excluded if they met any of the following exclusion criteria before cTnI
testing: death (all-cause); ST-Elevation MI (STEMI) [AHA criteria (14), adjudicated independently by a cardiologist]; and serious ventricular cardiac dysrhythmia.
Fresh EDTA plasma samples were simultaneously measured with both the contemporary cTnI
assays on the Abbott ARCHITECT i1000SR or i2000SR analyzer.
How can you prove a false-negative cTnI
in this patient and determine the cause?
We investigated whether there had been any change in the frequency of testing, the frequency of cTnI
increases above the 99th percentile, the rate of admission, the frequency of diagnoses of AMI (NSTEMI and STEMI), and the rate of angiography in men and women across 6 months use of each assay.
The company said the Singulex Clarity cTnI
assay runs on the Singulex Clarity system, a fully-automated, in vitro diagnostics platform powered by Single Molecule Counting technology.