Kinetics of high-sensitivity cardiac troponin T and I differ in patients with ST-segment elevation myocardial infarction treated by primary coronary intervention

Abstract

Purpose

Cardiac biomarkers including troponins are the cornerstone of the biological definition of acute myocardial infarction. New high-sensitivity cardiac assays determining troponin T (hs-cTnT) as well as I ((hs-cTnI) from Abbott and s-cTnI from Siemens) raise concerns because of their unclear kinetics following the peak.

Aims

This study aims to compare kinetics of creatine kinases, hs-cTnT, hs-cTnI and s-cTnI in patients with ST-segment elevation myocardial infarction (STEMI) treated by percutaneous coronary intervention.

Methods

We prospectively studied 106 consecutive patients admitted in our institution for STEMI and treated by percutaneous coronary intervention. We evaluated for all the patients simultaneously kinetics of creatine kinases, hs-cTnT (Roche) and two different cTnIs (hs-cTnI from Abbott and s-cTnI from Siemens). Modelling of kinetics was realized using mixed effects with cubic splines.

Results

Kinetics of markers showed a first peak at 10.7h (8.0–12.0) for creatine kinases, 11.8h (10.4–13.3) for hs-cTnT (Roche); 11.8h (10.7–11.8) for hs-cTnI from Abbott and 10.2h (8.7–11.6) for s-cTnI from Siemens, respectively. This peak was followed by a nearly log linear decrease for hs-cTnI/s-cTnI and creatine kinases in contrast to hs-cTnT, which appeared with a biphasic shape curve marked by a second peak at 76.9h (69.5–82.8). The analysis of the decrease in percentage of the peak value at 77h showed that hs-cTnT follows a twice lower decrease than other markers.

Conclusion

Kinetics of hs-cTnT, hs-cTnI and s-cTnI differ significantly with a linear decrease regarding both cTnI assays contrasting with a biphasic shape curve for hs-cTnT. This is of importance for clinical management of patients in routine settings especially in follow-up after STEMI including the suspicion of reinfarction.

Acute myocardial infarction, percutaneous coronary intervention, high-sensitivity troponin, creatine kinase, troponin I, troponin T, kinetics