Discordant Cardiac Biomarker Levels Independently Predict Outcome in ST-segment Elevation Myocardial Infarction

Aims: To investigate the prognostic relevance of elevated Troponin T (cTnT) levels in patients with ST-segment elevation myocardial infarction (STEMI) without significant creatine kinase (CK) elevation on admission.

Methods And Results: From January 1, 2002 to December 31, 2006 patients with STEMI without significant CK elevation (<2-fold) on admission treated with percutaneous coronary intervention (PCI) were included and stratified according to cTnT plasma levels. Univariate and multivariate regression analyses were used to find independent predictors for mortality. During the 5-year period 514 patients with STEMI and normal CK plasma levels were included. 308 (59.9 %) patients had cTnT levels <0.1 μg/l and 206 (40.1 %) patients had cTnT levels ≥0.1 μg/l. Multivariate logistic regression analysis identified cTnT levels ≥0.1 μg/l and 3-vessel disease as positive, and hemoglobin levels as negative independent predictors for long-term mortality. Discordantly elevated cTnT plasma levels independently predicted higher mortality rates in the first year (HR 3.9, 95 % CI 1.7-9.1, p = 0.002) and during 5 years (HR 2.3, 95 % CI 1.4-3.9, p = 0.002) after PCI for STEMI.

Conclusions: Discordant elevation of cTnT in the presence of normal CK plasma levels on admission is associated with increased mortality in STEMI patients undergoing primary PCI. This may be due to preceding microembolization.