ABSTRACT
Objective To evaluate the value of glycogen phosphorylase isoenzyme BB (GPBB) in the diagnosis of early acute myocardial infarction (AMI). Methods The plasma levels of GPBB were mea-sured by sandwich ELISA in 115 patients with suspected AMI at admission within 6 hours after onset of chest pain and 55 normal healthy subjects. The plasma concent of cardiac troponin-Ⅰ (cTnI), creatine kinase-MB (CK-MB) and myoglobin (MYO) was assayed at the same time by using corpuscle chemiluminescence. The patients were classified retrospectively into AMI group (n = 45) , unstable angina pectoris (UAP) group (n =40) , stable angina pectoris (SAP) group (n = 13) and non-cardiac chest pain (NCCP) group (n =17).The diagnostic validity was evaluated in terms of sensitivity and specificity. Results The diagnostic sensitivity of GPBB for AMI was 64.29 % within 3 hours and 88.89 % within 6 hours after onset of chest pain,which is significantly higher than that of cTnI (28.57 %, 60.00 %) and CK-MB (21.43 %, 64.44 % ). There was no significant difference in specificity among the four markers. The diagnostic accuracy of GPBB within 3hours and 6 hours (80.77 %, 89.57% ) was significantly higher than that of cTnI (61.54%, 81.74% ),CK-MB (50.00%, 75.65%) and MYO (73.08% ,73.91%). Conclusions GPBB seems to be a sensitive and specific biochemical cardiac marker for AMI in the early stage. Its diagnostic accuracy is higher than that of cTnI, CK-MB, MYO.