ABC | Volume 110, Nº1, January 2018

Original Article Soeiro et al Troponin vs. coronary lesion Arq Bras Cardiol. 2018; 110(1):68-73 1. Hollander JE, Than M, Mueller C. State-of-the-art evaluation of emergency department patients presenting with potential acute coronary syndromes. Circulation. 2016;134(7):547-64. doi: 10.1161/ CIRCULATIONAHA.116.021886. 2. Lipinski MJ, Baker NC, Escárcega RO , Torguson R, Chen F , Aldous SJ, et al. Comparison of conventional and high-sensitivity troponin in patients with chest pain: a collaborative meta-analysis. Am Heart J. 2015;169(1):6-16. e6. doi: 10.1016/j.ahj.2014.10.007. 3. Freund Y, Chenevier-Gobeaux C, Bonnet P , Claessens YE, Allo JC, Doumenc B, et al. High-sensitivity versus conventional troponin in the emergency department for the diagnosis of acute myocardial infarction. Crit Care. 2011;15(3):R147. doi: 10.1186/cc10270. 4. Zeller T, Tunstall-Pedoe H, Saarela O, Ojeda F, Schnabel RB, Tuovinen T, et al. High population prevalence of cardiac troponin I measured by a high-sensitivity assay and cardiovascular risk estimation: the MORGAM Biomarker Project Scottish Cohort. Eur Heart J. 2014;35(5):271-81. doi: 10.1093/eurheartj/eht406. 5. Aldous S, Mark Richards A, George PM, Cullen L, Parsonage WA, Flaws D , et al. Comparison of new point-of-care troponin assay with high sensitivity troponin in diagnosing myocardial infarction. Int J Cardiol. 2014;177(1):182-6. doi: 10.1016/j.ijcard.2014.09.026. 6. Carlton EW, Cullen L, Than M, Gamble J, Khattab A, Greaves K. A novel diagnostic protocol to identify patients suitable for discharge after a single high-sensitivity troponin. Heart. 2015;101(13):1041-6. doi: 10.1136/ heartjnl-2014-307288. 7. O´Gara PT, Kushner FG, Ascheim DD, Casey DE Jr, Chung MK, de Lemos JA, et al; American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2013;127(4):e362- 425. doi: 10.1161/CIR.0b013e3182742cf6. Erratum in: Circulation. 2013;128(25):e481. 8. Jneid H, Anderson JL, Wright RS, Adams CD, Bridges CR, Casey DE Jr, et al; American College of Cardiology Foundation; American Heart Association Task Force on Practice Guidelines. 2012 ACCF/AHA focused update of the guideline for the management of patients with unstable angina/non–ST-elevation myocardial infarction (updating the 2007 guideline and replacing the 2011 focused update): a report ofthe American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2012;126(7):875-910. doi: 10.1161/CIR.0b013e318256f1e0. References Finally, some studies have validated the new troponin assays. 1,19,20 The study conducted in 2015 compared seven assays of current sensitive troponins and high-sensitivity troponin in 2813 patients with chest pain, and with (16%) or without kidney dysfunction. Of the patients with nephropathy, in only 45-80% of those with positive troponin, the final diagnosis was myocardial infarction. The optimal cutoff point varied from 1.9 to 3.4 times that of the general population to detect acute coronary artery disease. Assessing only the same current sensitive troponin assay used in this study, in 27% of those with positive troponin, the final diagnosis of myocardial infarction was ruled out. The area under the curve of accuracy of that assay decreased from 0.92 to 0.87 (p = 0.013), comparing the general population with the patients with kidney dysfunction. 19 That cutoff point elevation is in accordance with our findings, showing a clear specificity reduction in the group of patients with nephropathy. Limitations Despite the large case series, this is a retrospective (hindering the blinded analysis) single-center study, with a much higher number of patients without chronic renal failure than with it. In addition, we used only one troponin assay, and most patients were of the male sex. Conclusion In the study population of patients with chest pain, sensitive troponin I showed a good correlation with significant coronary lesions when its level was greater than 0.605 ng/dL. In patients with chronic renal failure, a significant decrease in specificity was observed in the correlation of troponin levels and severe coronary lesions. Author contributions Conception and design of the research: Soeiro AM, Gualandro DM, Biselli B, Soeiro MCFA, Leal TCAT; Acquisition of data: Soeiro AM, Bossa AS, Zullino CN, Biselli B, Soeiro MCFA, Leal TCAT; Analysis and interpretation of the data: Soeiro AM, Gualandro DM; Statistical analysis: Soeiro AM, Gualandro DM, Soeiro MCFA; Obtaining financing: Soeiro AM; Writing of the manuscript: Soeiro AM, Leal TCAT; Critical revision of the manuscript for intellectual content: Soeiro AM, Serrano Jr. CV, Oliveira Junior MT. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associatedwith any thesis or dissertationwork. Ethics approval and consent to participate This study was approved by the Ethics Committee of the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo under the protocol number CAAE 38511114.7.0000.0068. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study. 72