Peak CKMB and cTnT accurately estimates myocardial infarct size after reperfusion

OBJECTIVES: To find the time-to-peak for creatine kinase MB(mass) (CKMB) and cardiac troponin T (cTnT) after acute reperfusion, to compare peak and cumulative values to estimate infarct size (IS), and to evaluate clinical routine sampling for assessment of IS. DESIGN: Acute primary percutaneous coronary intervention (PCI) was performed in 38 patients with first-time myocardial infarction. In 21 patients, CKMB and cTnT were acquired before PCI and at 1.5, 3, 6, 12, 18, 24, and 48 hours thereafter. In 17 patients, clinical routine samples were acquired at arrival, and at 10 and 20 h. IS was assessed by delayed contrast-enhanced MRI (DE-MRI). RESULTS: Time-to-peak was 7.6+/-3.6 h for CKMB and 8.1+/-3.4 h for cTnT. Peak values correlated strongly to cumulative values (r(s)=0.97-0.98) as well as to DE-MRI (r(s)=0.8-0.82). Clinical routine sampling showed lower rs values (0.47-0.60). CONCLUSIONS: Peak values are likely captured if CKMB and cTnT are acquired at 3, 6, and 12 h after acute PCI. These peak values can be used to estimate myocardial infarct size after acute PCI.