Biomarkers for risk stratification of patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention: Insights from the Platelet Inhibition and Patient Outcomes trial.

BACKGROUND: The incremental prognostic value of admission measurements of biomarkers beyond clinical characteristics and extent of coronary artery disease (CAD) in patients treated with primary percutaneous coronary intervention (PPCI) for ST-elevation myocardial infarction (STEMI) is unclear.

METHODS: Centrally analyzed plasma for biomarker measurements was available in 5,385 of the STEMI patients treated with PPCI in the PLATO trial. Extent of CAD was graded by operators in association with PPCI. We evaluated the prognostic value of high-sensitivity cardiac troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and growth differentiation factor 15 (GDF-15) beyond clinical characteristics and extent of CAD using Cox proportional hazards analyses, C-index, and net reclassification improvement (NRI). Outcomes were cardiovascular death (CVD) and spontaneous myocardial infarction (MI).

RESULTS: Angiographic data on extent of CAD improved the prediction of CVD compared to clinical risk factors alone, increasing the C-index from 0.760 to 0.778, total NRI of 0.31. Biomarker information provided additional prognostic value for CVD beyond clinical risk factors and extent of CAD, C-indices ranging from 0.792 to 0.795 for all biomarkers, but with a higher NRI for NT-proBNP. Extent of CAD and high-sensitivity cardiac troponin T were not associated with spontaneous MI. The prediction of spontaneous MI beyond clinical characteristics and extent of CAD (C-index 0.647) was improved by both NT-proBNP (C-index 0.663, NRI 0.22) and GDF-15 (C-index 0.652, NRI 0.05).

CONCLUSIONS: Biomarker measurement on admission is feasible and provides incremental risk stratification in patients with STEMI treated with PPCI, with NT-proBNP and GDF-15 being most valuable due to the association with both CVD and spontaneous MI.