Objectives: Non-ST elevation myocardial infarction (NSTEMI) is one of the most common manifestations of acute coronary syndromes (ACS). We evaluated the prognostic role of cardiac troponin I (cTnI) at presentation and peak cardiac troponin I in patients with NSTEMI. Methods: We consecutively enrolled 215 subjects presenting with NSTEMI. Subjects were followed up for 1 year. cTnI at presentation and the peak value of cTnI were measured. The primary end point was defined as cardiovascular death, readmission to hospital with heart failure and new ACS. Results: The subjects who presented the primary end point (49 subjects) had significantly increased values of peak cTnI compared to subjects free of cardiovascular events [7.19 (2.97-21.32) vs. 4.09 (1.18-11.85) ng/l; p = 0.002]. Nevertheless, cTnI at presentation did not differ between subjects who presented the primary end point and those free of events (p = 0.39). Multivariate Cox regression analysis after adjustment for confounders revealed by the univariate analysis showed that for an increase in peak cTnI from 1 to 10 ng/l, there is a 60% anticipated increase in the relative risk to present the primary end point (p = 0.04). Conclusion: These findings documented the different prognostic significance of cTnI at presentation and peak cTnI in patients presenting with NSTEMI, and highlighted the importance of monitoring the levels of cTnI in this high-risk population.

Keywords:
Non-ST elevation myocardial infarction, Cardiac troponin I, Acute coronary syndromes
1.
Roffi M, et al: 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: Task Force for the Management of Acute Coronary Syndromes in Patients Presenting without Persistent ST-Segment Elevation of the European Society of Cardiology (ESC). Eur Heart J 2016;37:267-315.
2.
Thygesen K, et al: How to use high-sensitivity cardiac troponins in acute cardiac care. Eur Heart J 2012;33:2252-2257.
3.
Thygesen K, et al: Third universal definition of myocardial infarction. J Am Coll Cardiol 2012;60:1581-1598.
4.
Apple FS, et al: Multicenter clinical and analytical evaluation of the AxSYM troponin-I immunoassay to assist in the diagnosis of myocardial infarction. Clin Chem 1999;45:206-212.
5.
Antman EM, et al: Cardiac-specific troponin I levels to predict the risk of mortality in patients with acute coronary syndromes. N Engl J Med 1996;335:1342-1349.
6.
Heidenreich PA, et al: The prognostic value of troponin in patients with non-ST elevation acute coronary syndromes: a meta-analysis. J Am Coll Cardiol 2001;38:478-485.
7.
Giannitsis E, et al: Admission troponin T level predicts clinical outcomes, TIMI flow, and myocardial tissue perfusion after primary percutaneous intervention for acute ST-segment elevation myocardial infarction. Circulation 2001;104:630-635.
8.
Macrae AR, et al: Assessing the requirement for the 6-hour interval between specimens in the American Heart Association Classification of Myocardial Infarction in Epidemiology and Clinical Research Studies. Clin Chem 2006;52:812-818.
9.
Kruse JM, et al: Weak diagnostic performance of troponin, creatine kinase and creatine kinase-MB to diagnose or exclude myocardial infarction after successful resuscitation. Int J Cardiol 2014;173:216-221.
10.
Iversen K, et al: Troponin T is a strong marker of mortality in hospitalized patients. Int J Cardiol 2013;168:818-824.
11.
Biener M, Katus HA, Giannitsis E: Challenges of serial troponin testing: a symphony in need for harmony. Int J Cardiol 2013;168:4542.
12.
Tousoulis D, et al: Assessment of acute coronary syndromes: focus on novel biomarkers. Curr Med Chem 2012;19:2572-2587.
13.
Tousoulis D, et al: New biochemical markers in acute coronary syndromes. Curr Med Chem 2008;15:1288-1296.
14.
Shah AS, et al: High-sensitivity cardiac troponin I at presentation in patients with suspected acute coronary syndrome: a cohort study. Lancet 2015;386:2481-2488.
15.
Hallén J: Troponin for the estimation of infarct size: what have we learned? Cardiology 2012;121:204-212.
16.
Thielmann M, et al: Prognostic value of preoperative cardiac troponin I in patients with non-ST-segment elevation acute coronary syndromes undergoing coronary artery bypass surgery. Chest 2005;128:3526-3536.
17.
Chin CT, et al: Comparison of the prognostic value of peak creatine kinase-MB and troponin levels among patients with acute myocardial infarction: a report from the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get with the Guidelines. Clin Cardiol 2012;35:424-429.
18.
Gonzalez MA, et al: Quartiles of peak troponin are associated with long-term risk of death in type 1 and STEMI, but not in type 2 or NSTEMI patients. Clin Cardiol 2009;32:575-583.
19.
Miller CD, et al: Stress CMR reduces revascularization, hospital readmission, and recurrent cardiac testing in intermediate-risk patients with acute chest pain. JACC Cardiovasc Imaging 2013;6:785-794.
20.
Fuernau G, et al: Osteoprotegerin in ST-elevation myocardial infarction: prognostic impact and association with markers of myocardial damage by magnetic resonance imaging. Int J Cardiol 2013;167:2134-2139.
© 2016 S. Karger AG, Basel
2016
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.