[Study on the clinical value of serum cardiac troponin T in early diagnosing of acute non-Q-wave myocardial infarction and prognostic evaluation].

Objective: To investigate the value of serum cardiac troponin T (cTnT) in diagnosing earlier acute non-Q-wave myocardial infarction (NQMI) and judging the prognosis.

Methods: Seventy-four NQMI patients and 118 Q-wave myocardial infarction (QMI) patients were studied. Serum cTnT and MB isoenzyme of creatine kinase (CK-MB) levels were monitored on fixed time. On the 15th day of hospitalization, 99 mTc-MIBI myocardial single photon emission computed tomography (SPECT) was performed to assess the infarct size index. Clinical informations of the two groups such as cardiac dysfunction, re-infarction, fatal cadiac arrhythmia, sudden death were collected.

Results: The time for serum cTnT beginning to rise was earlier than CK-MB. Its peak time value was paralled to that of CK-MB, and cTnT elevation lasted longer than CK-MB. Serum cTnT and CK-MB peak value showed positive correlation with the infarct size index (both P<0.01). The peak values of cTnT and CK-MB in NQMI group were lower than those in QMI group, and the infarct size was smaller than QMI group (all P<0.05). The frequencies of cardiac events were significantly raised in both groups when there was a high level of serum cTnT. But the proportion in NQMI group was less than those in QMI group (P<0.05). The cardiac events in NQMI group were less than that in QMI group (P<0.05).

Conclusion: Serum cTnT is an effective marker for diagnosing earlier NQMI, detecting myocardial damage, estimating infarct size and prognosis in the nearly future.