Comparison between cardiac troponin T and creatinine kinase MB mass in the diagnosis of myocardial infarction.

To the Editor: Recently, Paul Collinson and colleagues reported some results and perspectives about the diagnosis of myocardial infarction (MI). Here, we want to show some results in a public hospital of the State of Rio Grande do Sul, Brazil. Cardiac troponin T (cTnT) is considered the ‘gold standard’ in the diagnosis of MI since 2000, because of its high specificity for the heart muscle; however, due to high complexity and high cost of all services in Nether, the diagnosis for MI is done according to the symptomatology. 3 Creatinine kinase MB (CK-MB) mass is a biomarker with a little less specificity, nevertheless with low cost and more accessibility, useful in places with less technology. Information about the diagnosis of MI in public services in Brazil has so far not been published. Our aim is to present some data in a public hospital and establish a comparison between cTnT and CK-MB mass, evaluating the correlation and analysing the benefits for a public service. During the period of 1 year (October 2010 until September 2011) we analysed 148 patients of both genders. It was found that there is a significant correlation between the biomarkers. The correlation between cTnT and CK-MB mass was stronger in women. Strong correlation (p<0.005) was also demonstrated in patients in the age group of 60e69 years and 80e89 years. So, both biomarkers were effective for the diagnosis of MI. It is important to note that the time of MI was not analysed. In conclusion, when in the scarcity of cTnT, the use of CK-MB is acceptable. We agree with Paul Collinson and colleagues that the additional measurement of myoglobin and CK-MB does not provide further information in the diagnosis but we propose the use of CK-MB in centres that do not have cTnI or cTnT.