Immunoenzymometric assay of human glycogen phosphorylase isoenzyme BB in diagnosis of ischemic myocardial injury

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 41; no. 7; pp. 966 - 978
• Main Authors: Rabitzsch, G, Mair, J, Lechleitner, P, Noll, F, Hofmann, U, Krause, EG, Dienstl, F, Puschendorf, B
• Format: Journal Article
• Language: English
• Published: Washington, DC Am Assoc Clin Chem 01.07.1995; American Association for Clinical Chemistry
• Subjects: Adult; Aged; Antibodies, Monoclonal - immunology; Antibody Specificity; Biological and medical sciences; Cardiology. Vascular system; Clinical Enzyme Tests; Coronary heart disease; Creatine Kinase - blood; Female; Heart; Humans; Immunoenzyme Techniques - statistics & numerical data; Isoenzymes - blood; Kinetics; Male; Medical sciences; Middle Aged; Myocardial Infarction - diagnosis; Myocardial Infarction - enzymology; Myoglobin - blood; Phosphorylases - blood; Reference Values; Sensitivity and Specificity; Troponin - blood; Troponin T; Human; Infarct; Enzyme; Creatine kinase; Glycogen; Isozyme; Transferases; Glycosyltransferases; Biological marker; Cardiovascular disease; Enzyme immunoassay; Coronary heart disease; Phosphorylase; Clinical biology; Myocardium; Hexosyltransferases; Diagnosis
• ISSN: 0009-9147; 1530-8561
• DOI: 10.1093/clinchem/41.7.966

With a new immunoenzymometric assay we measured human glycogen phosphorylase isoenzyme BB (GPBB) in 116 healthy individuals, 14 patients with stable angina, 107 nontraumatic chest pain patients on admission to the emergency department [45 acute myocardial infarction (AMI), 49 unstable angina, 13 other diseases], and in serial samples from 41 AMI patients. GPBB was compared with creatine kinase (CK), CKMB mass, myoglobin, and cardiac troponin T. Receiver-operating characteristic plots demonstrated the significantly greater (P < or = 0.012) discriminatory power of GPBB to detect acute ischemic coronary syndromes compared with all other tested markers. GPBB was the most sensitive marker for detection of AMI during the first 4 h after onset of chest pain, and only GPBB was increased above the upper reference limit (7 micrograms/L) on admission in patients who had unstable angina at rest and reversible ST-T alterations. This and the high early sensitivity of GPBB are most likely explained by its function as a key enzyme of glycogenolysis.