Blood samples should be collected and assayed in intervals. ESC/ACC guidelines stress the importance of serial sampling. They recommend sampling at presentation of chest pain (baseline), then at 6 - 9 hours, and if these samples are negative and necrosis is still suspected, repeat samples at 12 - 24 hours. Some studies recommend sampling at presentation, 2 - 4 hours, 6 - 8 hours, and at 12 hours.
Biomarker measurement should be available 24 hours a day and the results presented within 30 - 60 minutes after sample collection.