A Risk Assessment Score and Initial High-sensitivity Troponin Combine to Identify Low Risk of Acute Myocardial Infarction in the Emergency Department

Introduction: Ruling out acute myocardial infarction (AMI) using serial troponin testing is central to the care of many emergency department (ED) patients with chest pain. While diagnostic strategies using conventional troponin assays require repeat sampling over many hours to avoid missed diagnoses, serial high-sensitivity troponin (hs-cTn) assays may be able to exclude AMI in most patients within 1 or 2 hours. However, many of the initial studies deriving and validating these rapid diagnostic algorithms had all hs-cTn samples analyzed in a central core lab likely representing optimal assay performance. This objective of this study is to validate a 1-hour rapid diagnostic algorithm to exclude AMI in ED chest pain patients using an hs-cTn assay in real world practice. Methods: This prospective cohort study was conducted at a single urban tertiary center and regional percutaneous coronary intervention site in Calgary, Alberta. Patients were eligible for enrolment if they presented to the ED with chest pain, were 25-years or older and required biomarker testing to rule out AMI at the discretion of the attending emergency physician. Patients were excluded if they had clear acute ischemic ECG changes, new arrhythmia or renal failure requiring hemodialysis. A high-sensitivity troponin result (Roche Elecsys hs-cTnT) was obtained in all patients at ED presentation and 1-hour later. The primary outcome was AMI on the index visit. Secondary outcomes included 30-day AMI and 30-day major adverse cardiac events (MACE - including AMI, revascularization or cardiac death). Electronic medical records were reviewed and telephone follow-up was obtained for all patients at 30-days to ensure relevant events were captured. Two physician adjudication (board-certified emergency physician and cardiologist) was obtained for all outcomes. The study was REB approved. Results: A total of 350 patients were enrolled from August 2014 September 2016 with 1-hour serial hs-cTnT results, of which 219 (62.6%) met the 1-hour rapid diagnostic algorithm low risk criteria (time 0h hs-cTnT <12ng/L and delta 1h <3ng/L). The sensitivity of the 1-hour low risk criteria for index AMI was 97.2% (95% CI 85.5%-99.9%) and for 30-day AMI was 97.3% (95% CI 85.8-99.9%). The sensitivity of the low risk criteria for 30-day MACE was lower 80.9% (95% CI 66.7-90.9%) but maintained a high negative predictive value, 95.9% (95% CI 92.3-98.1%). Conclusion: A 1-hour rapid diagnostic algorithm using an hs-cTnT assay was highly sensitive for AMI on the index visit and successfully identified patients at low risk of 30-day AMI; however, sensitivity for 30-day MACE was much lower. Of note, the 1-hour algorithm appears to be less sensitive for both AMI and 30-day MACE than a 2-hour algorithm validated in the same population.

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LO59: External validation of a 2-hour rapid diagnostic algorithm for ruling out acute myocardial infarction in emergency department patients with chest pain using a high-sensitivity troponin-T assay

CJEM ◽

10.1017/cem.2018.121 ◽

2018 ◽

Vol 20 (S1) ◽

pp. S27-S28

Author(s):

J. E. Andruchow ◽

T. S. Boyne ◽

S. Vatanpour ◽

D. Wang ◽

A. D. McRae

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Emergency Department ◽

Chest Pain ◽

Emergency Physician ◽

Diagnostic Algorithm ◽

High Sensitivity ◽

Low Risk ◽

Index Visit ◽

High Sensitivity Troponin

Introduction: Ruling out acute myocardial infarction (AMI) using serial troponin testing is central to the care of many emergency department (ED) patients with chest pain. While diagnostic strategies using conventional troponin assays require repeat sampling over many hours to avoid missed diagnoses, serial high-sensitivity troponin (hs-cTn) assays may be able to exclude AMI in most patients within 1 or 2 hours. However, many of the initial studies deriving and validating these rapid diagnostic algorithms had all hs-cTn samples analyzed in a central core lab likely representing optimal assay performance. This objective of this study is to validate a 2-hour rapid diagnostic algorithm to exclude AMI in ED chest pain patients using an hs-cTn assay in real world practice. Methods: This prospective cohort study was conducted at a single urban tertiary center and regional percutaneous coronary intervention site in Calgary, Alberta. Patients were eligible for enrolment if they presented to the ED with chest pain, were 25-years or older and required biomarker testing to rule out AMI at the discretion of the attending emergency physician. Patients were excluded if they had clear acute ischemic ECG changes, new arrhythmia or renal failure requiring hemodialysis. A high-sensitivity troponin result (Roche Elecsys hs-cTnT) was obtained in all patients at ED presentation and 2-hours later. The primary outcome was AMI on the index visit. Secondary outcomes included 30-day AMI and 30-day major adverse cardiac events (MACE - including AMI, revascularization or cardiac death). Electronic medical records were reviewed and telephone follow-up was obtained for all patients at 30-days to ensure relevant events were captured. Two physician adjudication (board-certified emergency physician and cardiologist) was obtained for all outcomes. This study was REB approved. Results: A total of 549 patients were enrolled from August 2014 September 2016 with 2-hour serial hs-cTnT results, of which 349 (63.6%) met the 2-hour rapid diagnostic algorithm low risk criteria (time 0 h/2 h hs-cTnT <14 ng/L and delta 2 h <4 ng/L). The sensitivity of the 2-hour low risk criteria for index AMI was 98.4% (95% CI 91.3%-100%) and for 30-day AMI was 98.4% (95% CI 91.6-100%). The sensitivity for 30day MACE was lower 84.4% (95% CI 74.4-91.7%) but maintained a high negative predictive value, 96.6% (95% CI 94.1-98.2%). Conclusion: A 2-hour rapid diagnostic algorithm using an hs-cTnT assay was highly sensitive for AMI on the index visit and successfully identified patients at low risk of 30-day AMI. Sensitivity for MACE was lower, reminding us that while biomarker-only rapid diagnostic algorithms excel at ruling out AMI, careful clinical risk stratification is needed to avoid missed MACE events.

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Immediate Rule-Out of Acute Myocardial Infarction Using Electrocardiogram and Baseline High-Sensitivity Troponin I

Clinical Chemistry ◽

10.1373/clinchem.2016.262659 ◽

2017 ◽

Vol 63 (1) ◽

pp. 394-402 ◽

Cited By ~ 34

Author(s):

Johannes Tobias Neumann ◽

Nils Arne Sörensen ◽

Francisco Ojeda ◽

Tjark Schwemer ◽

Jonas Lehmacher ◽

...

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Troponin I ◽

High Sensitivity ◽

Low Risk ◽

High Sensitivity Troponin ◽

Testing Trial ◽

Pain Symptoms ◽

Electrocardiogram Ecg ◽

Rule Out

Abstract AIMS Serial measurements of high-sensitivity troponin are used to rule out acute myocardial infarction (AMI) with an assay specific cutoff at the 99th percentile. Here, we evaluated the performance of a single admission troponin with a lower cutoff combined with a low risk electrocardiogram (ECG) to rule out AMI. METHODS Troponin I measured with a high-sensitivity assay (hs-TnI) was determined at admission in 1040 patients presenting with suspected AMI (BACC study). To rule out AMI we calculated the negative predictive value (NPV) utilizing the optimal hs-TnI cutoff combined with a low risk ECG. The results were validated in 3566 patients with suspected AMI [2-h Accelerated Diagnostic Protocol to Assess Patients With Chest Pain Symptoms Using Contemporary Troponins as the Only Biomarker (ADAPT) studies]. Patients were followed for 6 or 12 months. RESULTS 184 of all patients were diagnosed with AMI. An hs-TnI cutoff of 3 ng/L resulted in a NPV of 99.3% (CI 97.3–100.0), ruling out 35% of all non-AMI patients. Adding the information of a low risk ECG resulted in a 100% (CI 97.5–100.0) NPV (28% ruled out). The 2 validation cohorts replicated the high NPV of this approach. The follow-up mortality in the ruled out population was low (0 deaths in BACC and Stenocardia, 1 death in ADAPT). CONCLUSIONS A single hs-TnI measurement on admission combined with a low risk ECG appears to rule out AMI safely without need for serial troponin testing. Trial Registration: www.clinicaltrials.gov (NCT02355457).

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Point-of-care troponin T is inferior to high-sensitivity troponin T for ruling out acute myocardial infarction in the emergency department

European Journal of Emergency Medicine ◽

10.1097/mej.0000000000000225 ◽

2016 ◽

Vol 23 (2) ◽

pp. 95-101 ◽

Cited By ~ 15

Author(s):

Ewoud ter Avest ◽

Anniek Visser ◽

Bram Reitsma ◽

Rob Breedveld ◽

Albert Wolthuis

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Emergency Department ◽

Troponin T ◽

Point Of Care ◽

High Sensitivity ◽

High Sensitivity Troponin ◽

High Sensitivity Troponin T

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LO61: Test characteristics of high sensitivity troponin T performed at emergency department arrival for acute myocardial infarction in patients with reduced kidney function

CJEM ◽

10.1017/cem.2018.123 ◽

2018 ◽

Vol 20 (S1) ◽

pp. S28-S28

Author(s):

A. D. McRae ◽

S. Vatanpour ◽

J. Ji ◽

H. Yang ◽

D. Southern ◽

...

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Emergency Department ◽

Chest Pain ◽

Troponin T ◽

High Sensitivity ◽

Test Characteristics ◽

High Sensitivity Troponin ◽

High Sensitivity Troponin T ◽

Rule Out

Introduction: Patients with chronic kidney disease (CKD) are at high risk of cardiovascular events, and have worse outcomes following acute myocardial infarction (AMI). Cardiac troponin is often elevated in CKD, making the diagnosis of AMI challenging in this population. We sought to quantify test characteristics for AMI of a high-sensitivity troponin T (hsTnT) assay performed at emergency department (ED) arrival in CKD patients with chest pain, and to derive rule-out cutoffs specific to patient subgroups stratified by estimated glomerular filtration rate (eGFR). We also quantified the sensitivity and classification performance of the assays limit of detection (5 ng/L) and the FDA-approved limit of quantitation (6 ng/L) for ruling out AMI at ED arrival. Methods: Consecutive patients in four urban EDs from the 2013 calendar year with suspected cardiac chest pain who had a Roche Elecsys hsTnT assay performed on arrival were included f. This analysis was restricted to patients with an eGFR< 60 ml/min/1.73m2. The primary outcome was 7-day AMI. Secondary outcomes included major adverse cardiac events (death, AMI and revascularization). Test characteristics were calculated and ROC curves were generated for eGFR subgroups. Results: 1416 patients were included. 7-day AMI incidence was 10.1%. 73% of patients had an initial hsTnT concentration greater than the assays 99th percentile (14 ng/L). TCurrently accepted cutoffs to rule out MI at ED arrival ( 5 ng/L and 6 ng/L) had 100% sensitivity for AMI, but no patients with an eGFR less than 30 ml/min/1.73M had hsTnT concentrations below these thresholds. We derived eGFR-adjusted cutoffs to rule out MI with sensitivity >98% at ED arrival, which were able to rule out 6-42% of patients, depending on eGFR category. The proportion of patients able to be accurately ruled-in with a single hsTnT assay was substantially lower among patients with an eGFR <30 ml/min/1.73m2 (6-20% vs 25-43%). We also derived eGFR-adjusted cutoffs to rule-in AMI with specificity >90%, which accurately ruled-in up to 18% of patients. Conclusion: Cutoffs achieving acceptable diagnostic performance for AMI using single hsTnT sampling on ED arrival may have limited clinical utility, particularly among patients with very low eGFR. The ideal diagnostic strategy for AMI in patients with CKD likely involves serial high-sensitivity troponin testing with diagnostic thresholds customized to different eGFR categories.

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PCV43 High Sensitivity Troponin POINT of Care Testing for Cost-Effective EARLY Rule out of ACUTE Myocardial Infarction within the Emergency Department: An EARLY Economic Evaluation

Value in Health ◽

10.1016/j.jval.2020.08.534 ◽

2020 ◽

Vol 23 ◽

pp. S494

Author(s):

M. Bajre ◽

J. Hart ◽

A. Stainthorpe

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Emergency Department ◽

Economic Evaluation ◽

Point Of Care ◽

High Sensitivity ◽

Cost Effective ◽

Point Of Care Testing ◽

High Sensitivity Troponin ◽

Rule Out

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Serial high-sensitivity troponin measurements for the rapid exclusion of acute myocardial infarction in low-risk patients: Table 1

Emergency Medicine Journal ◽

10.1136/emermed-2012-201574 ◽

2012 ◽

Vol 30 (7) ◽

pp. 593-594 ◽

Cited By ~ 2

Author(s):

Charlotte Dawson ◽

Jonathan R Benger ◽

Graham Bayly

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

High Sensitivity ◽

Low Risk ◽

High Sensitivity Troponin ◽

Risk Patients

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The performance of high sensitivity troponin for the diagnosis of acute myocardial infarction is underestimated

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2011.830 ◽

2012 ◽

Vol 50 (4) ◽

Cited By ~ 2

Author(s):

Sally J. Aldous ◽

Chris M. Florkowski ◽

Ian G. Crozier ◽

Martin P. Than

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Emergency Department ◽

Acute Coronary Syndrome ◽

Diagnostic Performance ◽

High Sensitivity ◽

Clinical Use ◽

Coronary Syndrome ◽

High Sensitivity Troponin

AbstractMany papers evaluating high sensitivity troponin assays make the diagnosis of myocardial infarction based on conventional troponin assays in clinical use at the time of recruitment. Such analyses often do not show superiority of high sensitivity assays compared with contemporary assays meeting precision guidelines.Three hundred and twenty-two patients presenting to the emergency department between November 2006 and April 2007 for evaluation for acute coronary syndrome had serial (0 h and >6 h) bloods taken to compare troponin assays (Roche hsTnT, Abbott TnI, Roche TnT and Vitros TnI). The diagnosis of myocardial infarction was made using each troponin assay separately with which that same assay was analysed for diagnostic performance.The rate of myocardial infarction would be 38.9% using serial hsTnT, 31.3% using serial Abbott TnI, 27.1% using serial TnT and 26.4% using serial Vitros TnI. The baseline sensitivities (0 h) are 89.9% (85.2–93.3) for hsTnT, 77.9% (71.0–87.5) for Abbott TnI, 73.0% (65.6–78.7) for TnT and 86.8% (74.6–94.4%) for Vitros TnI. The specificities (peak 0 h and >6 h samples) are 93.1% (91.2–93.1) for hsTnT, 88.3% (86.5–88.3) for Abbott TnI, 92.2% (90.5–92.2) for TnT and 90.6% (70.1–90.6) for Vitros TnI.hsTnT has superior sensitivity for myocardial infarction than even assays at or near guideline precision requirements (Abbott and Vitros TnI). The specificity of hsTnT assay is not as poor as previous analyses suggest.

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