Rapid troponin T measurement in whole blood for detection of myocardial damage.

Abstract

A dry chemistry system for rapid qualitative measurement of cardiac troponin T in whole blood, serum, EDTA and lithium heparin plasma was studied in 197 admissions to the coronary care unit and general wards of a typical district general hospital for whom troponin T was requested. This included patients with unexplained collapse, acute dysrythmia or elevated creatine kinase of unknown origin. EDTA whole blood and plasma proved the most satisfactory sample matrices. Lithium heparin whole blood was equally appropriate but lithium heparin plasma gave a false negative result. Serum was an unsatisfactory sample material. Comparison with the conventional wet chemistry quantitative enzyme-linked immunosorbent assay showed a positive bias for EDTA plasma, particularly in the range 0-1 microgram/L and a significant negative bias for lithium heparin plasma. There was no difference between serum from plain or gel separator tubes. The whole blood method allows troponin T measurement to be performed rapidly and simply in the laboratory, either as an emergency test to alter patient management, or for those laboratories that wish to offer troponin T for selected cases but do not have the ability to measure troponin T quantitatively.