• cardiac troponin T
• acute myocardial infarction
• impaired left ventricular function

• ACS, acute coronary syndrome
• AMI, acute myocardial infarction
• AUC, area under the curve
• CK, creatine kinase
• cTnT, cardiac troponin T
• CV, coefficient of variation
• DGH, district general hospital
• LVEF, left ventricular ejection fraction
• ROC, receiver operator characteristic curve

Serial measurements of creatine kinase (CK) and its MB isoenzyme (CK-MB) and calculation of area under the curve (AUC) or peak value can be used to estimate infarct size. Peak values usually occur 20–24 hours postinfarction but release kinetics are affected by reperfusion (spontaneous or therapeutic). Regular, frequent samples must be obtained following admission, not a convenient approach for busy clinical or nursing staff. In a previous retrospective study¹ we demonstrated that an angiographically determined left ventricular ejection fraction (LVEF) < 40 % could be identified by a single cardiac troponin T (cTnT) measurement at the diagnostically efficient time point of 12–24 hours from admission. We performed a larger prospective study and compared the measurement of cTnT and peak CK with early estimation of LVEF by echocardiography.