Low-level troponin elevations following a reduced troponin I cutoff: Increased resource utilization without improved outcomes

Published:February 03, 2018DOI:



      The study sought to evaluate changes in mortality and resource utilization in patients with low level troponin elevations following a reduction in the cutoff for normal troponin I (TnI) from 0.5 ng/mL to the 99th percentile (0.06 ng/mL).


      This was an interrupted time series comparing emergency department (ED) patients with possible acute coronary syndrome (ACS) and TnI values 0.06–0.5 ng/mL before and after an institutional decrease in the TnI cutoff. The primary outcome was overall mortality at 90 days. Secondary outcomes included rates of rehospitalization, subsequent ACS, and coronary intervention within 90 days, as well as rates of anticoagulation, cardiology consultation, cardiac testing, and coronary intervention during the index visit. Outcomes for the pre-cutoff change group (control) and post-cutoff change group (post) were compared using tests of proportions and odds ratios.


      The study included a total of 1058 subjects with 529 in each cohort. No significant differences in 90 day outcomes were observed between groups, including mortality (13.2% post vs 14.1% control, OR 0.93 [95% CI: 0.65–1.34], p = 0.705). During the index visit, the post-group demonstrated higher rates of cardiology consultation (55.4% vs 41.2%, OR 1.77 [1.39–2.26], p < 0.0001) and cardiac stress testing (16.4% vs 10.6%, OR 1.66 [1.16–2.38], p = 0.006), but no significant differences in coronary intervention or short-term mortality were observed.


      A reduction in the TnI cutoff to the 99th percentile did not change mortality or rates of coronary intervention in ED patients with low level troponin elevations, but significantly increased the use of cardiology resources.


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        • Amsterdam E.A.
        • Wenger N.K.
        • Brindis R.G.
        • Casey Jr., D.E.
        • Ganiats T.G.
        • Holmes Jr., D.R.
        • et al.
        2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.
        J Am Coll Cardiol. 2014; 64: e139-228
        • Newby L.K.
        • Jesse R.L.
        • Babb J.D.
        • Christenson R.H.
        • De Fer T.M.
        • Diamond G.A.
        • et al.
        ACCF 2012 expert consensus document on practical clinical considerations in the interpretation of troponin elevations: a report of the American College of Cardiology Foundation task force on Clinical Expert Consensus Documents.
        J Am Coll Cardiol. 2012; 60: 2427-2463
        • Thygesen K.
        • Alpert J.S.
        • White H.D.
        • Joint ESCAAHAWHFTFftRoMI
        • Jaffe A.S.
        • Apple F.S.
        • et al.
        Universal definition of myocardial infarction.
        Circulation. 2007; 116: 2634-2653
        • Bonaca M.
        • Scirica B.
        • Sabatine M.
        • Dalby A.
        • Spinar J.
        • Murphy S.A.
        • et al.
        Prospective evaluation of the prognostic implications of improved assay performance with a sensitive assay for cardiac troponin I.
        J Am Coll Cardiol. 2010; 55: 2118-2124
        • Kim J.
        • Gaddam S.
        • Wu W.C.
        • Behera V.
        • Sharma S.
        • Choudhary G.
        Stratified reporting of high sensitivity troponin I assay is associated with suboptimal management of patients with acute coronary syndrome and intermediate troponin elevation.
        J Clin Lab Anal. 2013; 27: 402-406
        • Mills N.L.C.
        • D. A.M.
        • Lee K.K.
        • Anand A.
        • Gamble D.
        • Shah A.S.V.
        • et al.
        Implementation of a sensitive troponin I assay and risk of recurrent myocardial infarction and death in patients with suspected acute coronary syndrome.
        JAMA. 2011; 305: 1210-1216
        • van de Kerkhof D.
        • Peters B.
        • Scharnhorst V.
        Performance of the Advia Centaur second-generation troponin assay TnI-ultra compared with the first-generation cTnI assay.
        Ann Clin Biochem. 2008; 45: 316-317
        • von Elm E.
        • Altman D.G.
        • Egger M.
        • Pocock S.J.
        • Gotzsche P.C.
        • Vandenbroucke J.P.
        • et al.
        The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies.
        J Clin Epidemiol. 2008; 61: 344-349
        • Kaji A.H.
        • Schriger D.
        • Green S.
        Looking through the retrospectoscope: reducing bias in emergency medicine chart review studies.
        Ann Emerg Med. 2014; 64: 292-298
        • Gilbert E.H.
        • Lowenstein S.R.
        • Koziol-McLain J.
        • Barta D.C.
        • Steiner J.
        Chart reviews in emergency medicine research: where are the methods?.
        Ann Emerg Med. 1995; 27: 305-308
        • Bjurman C.
        • Zywczyk M.
        • Lindahl B.
        • Carlsson T.
        • Johanson P.
        • Petzold M.
        • et al.
        Decreased admissions and hospital costs with a neutral effect on mortality following lowering of the troponin T cutoff point to the 99th percentile.
        Cardiol J. 2017; 24: 612-622
        • Shah A.S.
        • McAllister D.A.
        • Mills R.
        • Lee K.K.
        • Churchhouse A.M.
        • Fleming K.M.
        • et al.
        Sensitive troponin assay and the classification of myocardial infarction.
        Am J Med. 2015; 128 ([e3]): 493-501
        • Meigher S.
        • Thode H.C.
        • Peacock W.F.
        • Bock J.L.
        • Gruberg L.
        • Singer A.J.
        Causes of elevated cardiac troponins in the emergency department and their associated mortality.
        Acad Emerg Med. 2016; 23: 1267-1273
        • Neumann J.T.
        • Sorensen N.A.
        • Schwemer T.
        • Ojeda F.
        • Bourry R.
        • Sciacca V.
        • et al.
        Diagnosis of myocardial infarction using a high-sensitivity troponin I 1-hour algorithm.
        JAMA Cardiol. 2016; 1: 397-404
        • Mueller M.
        • Celik S.
        • Biener M.
        • Vafaie M.
        • Schwoebel K.
        • Wollert K.C.
        • et al.
        Diagnostic and prognostic performance of a novel high-sensitivity cardiac troponin T assay compared to a contemporary sensitive cardiac troponin I assay in patients with acute coronary syndrome.
        Clin Res Cardiol. 2012; 101: 837-845
        • Kaambwa B.
        • Ratcliffe J.
        • Horsfall M.
        • Astley C.
        • Karnon J.
        • Coates P.
        • et al.
        Cost effectiveness of high-sensitivity troponin compared to conventional troponin among patients presenting with undifferentiated chest pain: a trial based analysis.
        Int J Cardiol. 2017; 1: 144-150