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Review
. 2021 Dec;107(23):1912-1919.
doi: 10.1136/heartjnl-2019-316242. Epub 2021 Sep 3.

Implementing an early rule-out pathway for acute myocardial infarction in clinical practice

Matthew T H Lowry  1 , Atul Anand  1 , Nicholas L Mills  2   3
Affiliations
Review

Implementing an early rule-out pathway for acute myocardial infarction in clinical practice

Matthew T H Lowry et al. Heart. 2021 Dec.
No abstract available

Keywords: acute coronary syndrome; chest pain; myocardial infarction.

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Conflict of interest statement

Competing interests: AA has received honoraria from Abbott Diagnostics. NLM reports research grants awarded to the University of Edinburgh from Abbott Diagnostics and Siemens Healthineers outside the submitted work, and honoraria from Abbott Diagnostics, Siemens Healthineers, Roche Diagnostics and LumiraDx. All other authors have no interests to declare.

Figures

Figure 1
Figure 1
Illustration of cardiac troponin release following the onset of chest pain in acute myocardial infarction. The use of high-sensitivity cardiac troponin assays with separate rule-out and diagnostic thresholds enables earlier clinical decisions. Due to the time delay of troponin detection, patients who present early (within 2 or 3 hours of symptom onset) require serial testing.
Figure 2
Figure 2
Thresholds to rule out and rule in the diagnosis of myocardial infarction with high-sensitivity cardiac troponin testing. The histogram illustrates the distribution of cardiac troponin in a healthy reference population. High-sensitivity assays can measure cardiac troponin in the majority of the reference population, but concentrations are right-skewed, with the majority of healthy persons having concentrations below the optimised rule-out threshold. The limit of detection (LoD) and optimised thresholds are used to rule out myocardial infarction, and the 99th centile and optimised rule-in thresholds are used to guide further investigations. UDMI, Universal Definition of Myocardial Infarction (the sex-specific 99th centile is the recommended UDMI diagnostic threshold).
Figure 3
Figure 3
Schematic diagram of an early rule-out pathway using separate rule-out and diagnostic thresholds. The High-STEACS early rule-out pathway is recommended by the ESC and NICE guidelines and uses separate rule-out and diagnostic thresholds with a second test in the ED if needed. Myocardial infarction is ruled out at presentation in patients with hs-cTn (Abbott Diagnostics, Siemens Healthineers, Roche Diagnostics) concentrations <5 ng/L, unless they presented within 2 hours of symptom onset, where testing is repeated. Patients with cardiac troponin concentrations ≥5 ng/L but below the 99th centile at presentation are retested in the ED 3 hours after presentation (~2 hours between samples), and myocardial infarction is ruled out if concentrations are unchanged (<3 ng/L) and remain below the 99th centile diagnostic threshold. A quarter of all patients with suspected acute coronary syndrome have hs-cTn concentrations above the diagnostic threshold or increasing in the reference range, and hospital admission should be considered for further investigation and testing 6–12 hours after symptom onset. ED, emergency department; ESC, European Society of Cardiology; High-STEACS, High-Sensitivity Troponin in the Evaluation of Acute Coronary Syndromes; hs-cTn, high-sensitivity cardiac troponin; NICE, National Institute for Health and Care Excellence.
Figure 4
Figure 4
Schematic diagram of an early rule-out pathway using multiple thresholds. This pathway is recommended by the ESC and NICE guidelines and has been validated for multiple hs-cTn assays (Roche Diagnostics, Abbott Diagnostics, Siemens Centaur, Beckman Coulter Access) using six assay-specific thresholds or change values to triage patients into rule-out, observe or rule-in groups. Myocardial infarction is ruled out if cardiac troponin concentrations are ‘very low’ (thresholds near or at the limit of detection) in patients presenting at least 3 hours from chest pain onset. Myocardial infarction is ruled in using a single ‘high’ cardiac troponin threshold at presentation, but serial testing is recommended and the diagnosis based on demonstrating a rise and/or fall in cardiac troponin with one value above the 99th centile diagnostic threshold. Patients with intermediate cardiac troponin concentrations between ‘very low’ and ‘high’ should have a second sample 1 or 2 hours after the first test. Myocardial infarction is ruled out at this second step if the repeat concentration is ‘low’ and there is no significant change using a ‘rule-out delta’ value. Myocardial infarction is ruled in if cardiac troponin concentrations are now ‘high’ or there has been an increase in concentrations above the ‘rule-in delta’ value. It should be noted that these thresholds and delta values differ depending on whether serial testing is performed at 1 or 2 hours. Patients with symptom onset <3 hours or intermediate hs-cTn concentrations following the second test between ‘low’ and ‘high’ or an intermediate delta change value between the ‘rule-out delta’ and the ‘rule-in delta’ are triaged to the observed zone, where a third test 3 hours from the first sample is recommended along with echocardiography. On review of these results clinicians should use clinical judgement to guide further management, and the diagnosis of myocardial infarction is based on documenting a rise and/or fall of hs-cTn with any value above the 99th centile, in line with the universal definition. ESC, European Society of Cardiology; hs-cTn, high-sensitivity cardiac troponin; NICE, National Institute for Health and Care Excellence.
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References

    1. Goodacre S, Cross E, Arnold J, et al. . The health care burden of acute chest pain. Heart 2005;91:229–30. 10.1136/hrt.2003.027599 - DOI - PMC - PubMed
    1. Collet J-P, Thiele H, Barbato E, et al. . 2020 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation. Eur Heart J 2021;42:1289–367. 10.1093/eurheartj/ehaa575 - DOI - PubMed
    1. National Institue for Health and Care Excellence . High-sensitivity tests for the early rule-out of NSTEMI [DG40]; 2020.
    1. Apple FS, Sandoval Y, Jaffe AS, et al. . Cardiac troponin assays: guide to understanding analytical characteristics and their impact on clinical care. Clin Chem 2017;63:73–81. 10.1373/clinchem.2016.255109 - DOI - PubMed
    1. Chew DP, Lambrakis K, Blyth A, et al. . A randomized trial of a 1-hour troponin T protocol in suspected acute coronary syndromes. Circulation 2019;140:1543–56. 10.1161/CIRCULATIONAHA.119.042891 - DOI - PubMed

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