DOI: http://dx.doi.org/10.18203/2349-3933.ijam20170119

Sensitivity and specificity of cardiac troponin-T in diagnosis of acute myocardial infarction

Dharmveer Sharma, Poonam Gupta, Sagar Srivastava, Harshit Jain

Abstract


Background: Myocardial Infarction is the irreversible necrosis of the heart muscle secondary to prolong lack of oxygen supply. Troponin T is a structurally bound protein found in striated muscle cells. They have rapidly attained central role in diagnosis, prognostication and planning of therapeutic strategies in MI patients. The objective of this study was to evaluate the status of Troponin T in MI patients and its role in diagnosis compare to normal subjects.

Methods: The study was conducted at M. L .N. Medical College, Allahabad, Uttar Pradesh India. A total of 136 cases were included in our study. Out of these, 86 were patients of AMI and 50 were healthy controls. They were evaluated by measurement of various parameters including enzymatic markers such as CPK-MB, SGOT, LDH1, and LDH2 and non-enzymatic markers such as troponin-T and myoglobin. Apart from these, LDL, VLDL and HDL levels were also kept under evaluation.

Results: Troponin-T test was better than CPK-MB or SGOT in diagnosing myocardial infarction. In our study, sensitivity (67.3%) and specificity (73.8%) of troponin-T test was higher than CPK-MB (56.2% and 45.7%) and SGOT (34.2% and 58.3%) respectively. Troponin-T test was better than CPK-MB or SGOT after 2 hours of onset of myocardial infarction. Troponin- T and I: both kind of evaluations are available and are well evaluated. However troponin T estimation is more standardized and thus more popular. The positivity of troponin-T test also varied with area of infarct.

Conclusions: High LDL and VLDL were seen while at the same time HDL level was lowered. An Increase in the level of myoglobin (non-specific marker), Cardiac troponin I and T and among the enzymatic markers elevated levels of CPK-MB, LDH and SGOT were observed in patients of MI against the normal subjects. In case of LDH both LDH 1 and LDH 2 were observed and a flipped pattern was noted. Bedside troponin-T test is highly sensitive and specific in the diagnosis of acute myocardial infarction and can be used in emergency and ambulatory settings. Qualitative troponin-T test is reliable above serum level of ≥ 0.10 ng/ml.


Keywords


MI, TnT, CPK-MB, LDH

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