Serum Cardiac Troponin T in Unstable Angina Pectoris Patients
WATTANA LEOWATTANA, M.D.*, KIERTUAI BHURIPANYO, M.D.**, SUDCHAREE KIARTIVICH, M.Sc.* NITHI MAHANONDA, M.D.**, SASIKANT POKUM, B.Sc.*
Affiliation : * Department of Clinical Pathology, ** Her Majesty Cardiac Center, Faculty of Medicine Siriraj Hospital, Mahidol University. Bangkok 10700. Thailand.
Cardiac troponin T (cTnT) is a regulatory contractile protein not normally found in blood. Its detection in the circulation has been shown to be a sensitive and specific marker for myo- cardial cell damage. In this study, we used a second-generation enzyme immunoassay for cTnT to determine whether its presence in the serum of patients with unstable angina was a prognostic indicator. Thirty patients with unstable angina pectoris (UAP) and 30 patients with Q-wave acute myocardial infarction (AMI) were screened for serum CK-MB activity and cTnT at 6, 12, 24 and 48 hours after the onset of chest pain. All of the mean concentrations of CK-MB activity determined in UAP patients were less than the upper limit of normal (25 U/L). Meanwhile. the mean concentration of cTnT at 6, 12, 24 and 48 hours after onset of chest pain were higher than the cutoff values (0.1 J..lg!L). We found that one third of UAP patients had serum cTnT at the time of admission more than 0.1 J..lg/L and that these groups of patients were associated with a high risk for cardiac events. Our results suggested that patients with elevated serum cTnT could be considered as high-risk patients for developing myocardial infarction. Patients with normal cTnT levels and a low or intermediate clinical risk could be stabilized and further stratified noninvasively.
Keywords : Troponin T, Unstable Angina
