Acute myocardial infarction in chest pain patients with nondiagnostic ECGs: Serial CK-MB sampling in the emergency department

Abstract Introduction According to ESC guidelines, an acute myocardial infarction (MI) can be excluded without serial troponin measurements in patients presenting with a single high-sensitive troponin below the 99th percentile and chest pain starting >6 hours prior to admission. However, it is unclear if single-testing of high-sensitive troponin can rule-out MI in early presenters. Purpose To investigate the diagnostic performance of a single value of high-sensitive cardiac troponin I (hs-cTnI) at presentation for ruling-out MI in patients presenting with chest pain to the Emergency Department irrespective of chest pain onset. Methods We conducted a substudy of preliminary data from the RACING-MI trial. We included patients presenting with chest pain suggestive of MI to the Emergency Department of a Regional Hospital. We used the Siemens hs-cTnI (Siemens Healthcare, TNIH, Limit of detection: 2.21 ng/L) and a diagnostic cut-off value <3 ng/L to rule-out MI at presentation. Two physicians independently adjudicated the final diagnosis based on all clinical information. Patients were stratified based on time from chest pain onset to hospital admission as very early (0–3 hours), early (3–6 hours) and late presenters (>6 hours). Results We included 989 patients with available hs-cTnI results at admission. MI was confirmed in 82 (8.3%) patients. Using hs-cTnI <3 ng/L as diagnostic cut-off value at presentation, 302 (30.5%) patients without MI were classified as rule-out. Overall, the negative predictive value (NPV) for MI was 100% (95% CI 98.7–100). Based on chest pain onset, 33.8% of patients were classified as very early, 12.8% as early, and 42.7% as late presenters, with 10.7% patients with unreported/unknown onset. NPV was 100% (95% CI 96.5–100) for very early, 100% (95% CI 88.3–100) for early and 100% (95% CI 97.3–100) for late presenters. Conclusions Using a single hs-cTnI value <3ng/L as diagnostic cut-off to rule-out MI seems to be safe and to allow rapid rule-out of MI in patients presenting with chest pain to the emergency department, even in very early presenters. ClinicalTrials.gov Identifier: NCT03634384. Acknowledgement/Funding Randers Regional Hospital, A.P Møller Foundation, Boserup Foundation, Korning Foundation, Højmosegård Grant, Siemens Healthcare (TNIH assays), etc.

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Incidence of Myocardial Infarction in Emergency Department Chest Pain Patients with a Recent Negative Stress Imaging Test

Academic Emergency Medicine ◽

10.1197/j.aem.2005.03.138 ◽

2005 ◽

Vol 12 (Supplement 1) ◽

pp. 51-51 ◽

Cited By ~ 3

Author(s):

S. W. Smith

Keyword(s):

Myocardial Infarction ◽

Emergency Department ◽

Chest Pain ◽

Stress Imaging ◽

Imaging Test ◽

Pain Patients

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Artificial neural network algorithms for early diagnosis of acute myocardial infarction and prediction of infarct size in chest pain patients

International Journal of Cardiology ◽

10.1016/j.ijcard.2005.12.019 ◽

2007 ◽

Vol 114 (3) ◽

pp. 366-374 ◽

Cited By ~ 32

Author(s):

Kai M. Eggers ◽

Johan Ellenius ◽

Mikael Dellborg ◽

Torgny Groth ◽

Jonas Oldgren ◽

...

Keyword(s):

Neural Network ◽

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Artificial Neural Network ◽

Chest Pain ◽

Early Diagnosis ◽

Infarct Size ◽

Network Algorithms ◽

Artificial Neural ◽

Pain Patients

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Predictive Value of a 6-Hour Ecg/Troponin Protocol in Patients with Chest Pain

Hong Kong Journal of Emergency Medicine ◽

10.1177/102490790301000303 ◽

2003 ◽

Vol 10 (3) ◽

pp. 146-152 ◽

Cited By ~ 1

Author(s):

CY Man ◽

PA Cameron ◽

WL Cheung

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Acute Coronary Syndrome ◽

Chest Pain ◽

Troponin T ◽

Low Risk ◽

Chinese Patients ◽

Initial Assessment ◽

Coronary Syndrome ◽

Pain Patients

Introduction Patients presenting with chest pain and considered to be at low risk of acute coronary syndrome (ACS) may still have coronary heart disease. The potential risk of sudden cardiac death due to arrhythmias or progression to acute myocardial infarction still exists. To minimize this risk, we have designed a 6-hour risk stratification protocol for patients with a low risk of acute myocardial infarction on initial assessment in the Accident and Emergency Department (AED). Materials & Methods This was a retrospective observational study with the aim of determining the risk of adverse cardiovascular events in chest pain patients attending an AED. These patients were subject to an ECG and cardiac troponin T tests (cTnT) at 0 hour and at 6 hours (if the two tests were negative at 0 hour), and were put under observation in the AED observation ward during the same period. The main outcome measures were adverse cardiac events at 30 days. Results A total of 371 Chinese patients considered to have low risk of ACS were recruited into the protocol. Troponin T tested positive in 19 patients (5.1%) at 0 hour and 8 patients (2.2%) at 6 hours. Amongst the 332 patients that were discharged directly from the AED, there were no re-admissions for cardiac-related deaths, acute myocardial infarction, arrhythmia or heart failure. Conclusion The 6-hour ECG and troponin T observation protocol is a useful tool to allow safe discharge of chest pain patients who are at low risk of acute coronary syndrome.

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Autoantibody prevalence with an improved immunoassay for detecting cardiac troponin-specific autoantibodies

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2013-0310 ◽

2014 ◽

Vol 52 (2) ◽

Cited By ~ 7

Author(s):

Tanja Savukoski ◽

Tuomo Ilva ◽

Juha Lund ◽

Pekka Porela ◽

Noora Ristiniemi ◽

...

Keyword(s):

Myocardial Infarction ◽

Emergency Department ◽

Chest Pain ◽

Cardiac Troponin ◽

Troponin I ◽

State Of The Art ◽

Cardiac Troponin I ◽

High Prevalence ◽

Sandwich Type ◽

Pain Patients

AbstractCardiac troponin-specific autoantibodies (cTnAAb) can interfere with the measurement of cardiac troponin I (cTnI) by immunoassays used for the diagnosis of myocardial infarction (MI). Here, an improved version of a previous autoantibody assay was validated and used to evaluate the cTnAAb prevalence in a cohort of consecutive chest pain patients presenting to an emergency department.Admission samples from 510 patients with suspected MI were analyzed in parallel with two sandwich-type cTnAAb assays based on different cTnI epitopes used to capture cardiac troponin-bound cTnAAbs.Sample-specific backgrounds were lower for the new assay than for the old assay (median 1225 vs. 2693 counts, p<0.001). Net signals of cTnAAb-positive samples were higher for the new assay than for the old assay (median 5076 vs. 3921 counts, p<0.001). Of all patients, 9.2% were cTnAAb-positive for the new assay and 7.3% for the old assay (p=0.013). Previous cardiac problems were not associated with cTnAAb status and cTnAAb status did not correlate with the 12-month outcome.With our new and more sensitive autoantibody assay, approximately one out of ten patients who presented to the initial cardiac triage had detectable amounts of cTnAAbs in the circulation. Because these cTnAAbs can interfere with state-of-the-art cTnI assays, their high prevalence should be acknowledged by clinical chemists, physicians, and kit manufacturers.

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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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