[Macromolecular complex of cardiac troponin I: differences of reactivity with DPC and Dade-Behring assays].
We have recently identified a macromolecular 440-kDa cardiac troponin I (cTnI) complex after successful percutaneous transluminal coronary angioplasty (PTCA) (Clin Chem 2003; 49: 505-7). The aim of the work was to confirm the existence of such a complex by using another cTnI assay (Dimension RXL, Dade-Behring). We have first studied the correlation between the two assays by using heparinized samples [cTnI(Immulite) = 2.00 cTnI(Dimension) - 0.01 (n = 176; r = 0,987)]. Then, cTnI taken 120 minutes after PTCA for two patients was measured with the two assays after fractionation by FPLC. The obtained results confirmed the existence of the 440-kDa cTnI complex and showed that the reactivity between the assays (DPC/Dade-Behring ratio) depended on the nature of the complex: the ratio increased from 0.7 (440-kDa cTnI complex) to 3 (80-kDa cTnI complex) therefore suggesting caution in the comparison between the different cTnI assays in the context of reperfusion therapy.
Lavoinne
A
A
Laboratoire de biochimie médicale, Hôpital Charles Nicolle, Centre hospitalier universitaire et régional de Rouen. alain.lavoinne@chu-rouen.fr
Cauliez
B
B
Duflo-Leroy
A
A
Tron
C
C
Eltchaninoff
H
H
D015906:Angioplasty, Balloon, Coronary; D015415:Biomarkers / Q000097:blood; D006801:Humans; D015425:Myocardial Reperfusion; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I