Chattington P, Clarke D, Neithercut W D
Department of Medicine for the Elderly, Wirral Hospital NHS Trust, Upton.
J Clin Pathol. 1994 Nov;47(11):995-8. doi: 10.1136/jcp.47.11.995.
To assess the value of timed sequential analysis of creatine kinase (CK) activity for the early diagnosis of acute myocardial infarction (AMI) in patients over 65 years of age.
Samples were collected on admission and eight to 12 hours later from 156 patients over 65 years of age. Routine cardiac enzyme activities were determined and serial electrocardiograms (ECGs) recorded. The predictive value of timed samples for CK activity, standard cardiac enzyme activities, and ECGs was compared with the final diagnosis on discharge.
Forty one patients had a discharge diagnosis of AMI, 83 of angina pectoris, and the remaining 32 patients had other diagnoses. Electrocardiograms had a sensitivity of 55% and a specificity of 96%, giving a predictive value of 86% for a negative and 84% for a positive ECG. Standard cardiac enzymes had a predictive value of 99% for a negative result but only 68% for a positive result. The logarithm of the rate of change of CK activity had a predictive value of 97% for a negative result and 95% for a positive result.
This study has shown that slope analysis of CK activity can be used for the early diagnosis of AMI in patients over 65 years of age, and that this was not affected by the presence of possible confounding diagnoses.
评估肌酸激酶（CK）活性的定时序贯分析对65岁以上急性心肌梗死（AMI）患者早期诊断的价值。
收集156例65岁以上患者入院时及8至12小时后的样本。测定常规心肌酶活性并记录系列心电图（ECG）。将CK活性定时样本、标准心肌酶活性及ECG的预测价值与出院时的最终诊断进行比较。
41例患者出院诊断为AMI，83例为心绞痛，其余32例患者有其他诊断。心电图的敏感性为55%，特异性为96%，ECG阴性预测值为86%，阳性预测值为84%。标准心肌酶阴性结果的预测值为99%，阳性结果的预测值仅为68%。CK活性变化率的对数阴性结果的预测值为97%，阳性结果的预测值为95%。
本研究表明，CK活性的斜率分析可用于65岁以上AMI患者的早期诊断，且不受可能存在的混淆诊断的影响。
