Prognostic significance of troponin T in acute myocardial infarction
Keywords:Ejection fraction, STEMI, Streptokinase, Troponin T, Thrombolysis
Background: Cardiac markers traditionally have been used only to establish the diagnosis in patients with acute coronary syndromes. In those with suspected acute STEMI, markers have been deemed to have little value, although smaller studies have suggested that troponin T may be valuable for risk stratification. Study aim was to study the prognostic significance of admission Troponin T in acute STEMI and also the relation between Troponin positivity and ST segment resolution after thrombolysis and also relationship with ejection fraction by echocardiogram.
Methods: This was a descriptive study conducted in 50 patients admitted with acute STEMI within eight hours in the department of medicine in a tertiary care centre in South Kerala. A blood sample was sent for assessing troponin T. All Patients underwent thorough clinical examination and investigations including echocardiogram was done and were managed with thrombolysis. They were closely followed up for in hospital and 30 days mortality and complications. ST segment resolution after thrombolysis with streptokinase was also assessed.
Results: In present study 48% of the patients were troponin T positive. Total six patients died of which all were Troponin T positive. There was a significant increase in the complications in troponin T positive group (46% vs 16%). 44% of the patients had an anterior wall myocardial infarction of which 46% had complications. ST segment resolution after thrombolysis was below 30% in 66.7% of the troponin T positive patients. Ejection fraction was below 50% in 80% of troponin T positive patients.
Conclusions: There was a statistically significant correlation between admission troponin T levels and in hospital complications and also mortality rates at 30 days. Troponin T positivity at admission was significantly associated with lower rates of reperfusion after thrombolysis with streptokinase and also lower rate of ejection fraction on echocardiogram. Troponin T positive anterior wall myocardial infarction was associated with more complications than non-anterior wall myocardial infarction.
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