Evaluation of serum troponin-tar a new cardiac marker in cases of acute myocardial infarction

ABSTRACT

The study included 75 consecutive patients with chest pain and suspected for AMI, who comprises 46 patients having sustained AMI, 24 patients with AMI ruled out and 5 patients with non-cardiac chest pain. All were admitted to coronary care unit within 6 hours from the onset of chest pain. For comparative purposes the study also included 17 patients with either polytraumatized muscles or extrathoracic surgery, besides 15 healthy blood donors who were age comparable to patients. Blood samples were obtained from patients with chest pain on admission [0 - 6 hours] and in the range of 12 - 24 hours after onset of chest pain. In case of polytraumatized subjects blood samples were obtained after 12 hours from either the trauma or surgery. A single blood sample was obtained from controls. From each sample, serum was separated and used for determination of troponin-T myoglobin, creatine kinase [CK] and its isoenzyme [CK-MB], lactate dehydrogenase [LDH] and its isoenzyme [LDH-1]. At a cutoff value of 0.2 mug/L cardiac troponin-T measurements [0 - 6 hours and 12 - 24 hours] after the onset of chest pain were significantly higher in patients with AMI than in patients with non-AMI, traumatized patients or healthy controls. Such significant difference was not found in the other biochemical cardiac indices, i.e. myoglobin, CK, CK-MB, LD and LDH-1. Furthermore, cardiac troponin-T had the high sensitivity, specificity and diagnostic efficiency for the diagnosis of AMI in either 0 - 6 or 12 - 24 hours measurements after the onset of chest pain as compared with all the above other biochemical cardiac indices