This is the current release of the guideline.

Definitions for the strength of evidence (Class I-III) and strength of recommendations (Level A-C) are repeated at the end of the "Major Recommendations" field.

1. Are serial electrocardiograms (ECGs) useful during the emergency department (ED) evaluation of patients with suspected acute coronary syndromes?

   Level A recommendations. None specified.

   Level B recommendations. Perform repeat ECG or automated serial ECGs during the ED evaluation of patients in whom the initial ECG is nondiagnostic for injury and who have symptoms consistent with ongoing or recurrent ischemia.

   No recommendations can be made in regards to the exact timing of repeat ECGs. Studies suggest that 30 to 60 minutes after baseline may be a reasonable time interval for repeat ECG.

   Level C recommendations. None specified.

2. Is there a preferred regimen of serum marker testing in the ED for the exclusion of non–ST-segment elevation acute myocardial infarction (AMI)?

   Inclusion Criteria. Patients with symptoms suggestive of acute coronary syndromes presenting less than or equal to 12 hours of symptom onset.

   Level A recommendations. Do not utilize cardiac serum marker tests to exclude non-AMI acute coronary syndromes (i.e., unstable angina).

   Level B recommendations. Utilize any of the following cardiac serum marker tests to exclude non–ST-segment elevation AMI as defined by the World Health Organization (WHO) or modified WHO criteria (see below):*

   1. A single negative creatine kinase MB band (CK-MB) mass, Troponin I, or Troponin T measured 8 to 12^a hours after symptom onset^b
   2. A negative myoglobin in conjunction with a negative CK-MB mass, or negative Troponin^c when measured at baseline and 90 minutes in patients presenting less than 8 hours after symptom onset^b
   3. A negative 2-hour delta^d CK-MB mass in conjunction with a negative 2-hour delta^d Troponin^c in patients presenting less than 8 hours after symptom onset^b

   Level C recommendations. None specified.

   *There is insufficient evidence at this time to make any recommendations in regards to utilization of cardiac serum markers to exclude non–ST-segment elevation AMI using current Joint European Society of Cardiology (ESC)/ACC criteria for AMI (see Figure 2 in the original guideline document).

   ^aThe exact timing of serum marker measurement as it relates to time of symptom onset should take into account the sensitivity, precision, and institutional norms of the assay being utilized, as well as the release kinetics of the marker being measured.

   ^bIf time of symptom onset is unknown, unreliable, or more consistent with preinfarctional angina, then time of symptom onset should be referenced to the time of ED presentation.

   ^cOnly Troponin I has been investigated in the serial 90 minute multimarker protocol and the 2-hour delta protocol.

   ^dThe appropriate delta values for exclusion of AMI should take into account the sensitivity and precision of the assay utilized and confirmed by in-house studies. It is also important that delta serum marker levels are measured on the same instrument due to subtle variations in calibration among individual instruments of the same model.

3. What are the indications for ED administration of glycoprotein IIb/IIIa inhibitors in patients with non-ST-segment elevation acute coronary syndromes?

   Exclusion Criteria: Contraindications for a glycoprotein inhibitor (bleeding disorder, renal insufficiency, etc).

   Level A recommendations. None specified.

   Level B recommendations. Consider administration of glycoprotein IIb/IIIa inhibitors (abciximab, tirofiban, or eptifibatide) prior to percutaneous coronary intervention to patients with positive troponin or ischemic ST-segment depression in whom an early interventional strategy is anticipated.* Studies suggest that benefit is greatest in patients in whom treatment was initiated within 6 hours of symptom onset and in patients in whom there will be a delay in percutaneous coronary intervention.

   Level C recommendations. Consider administration of glycoprotein IIb/IIIa inhibitors (tirofiban or eptifibatide) to patients with positive troponin or ischemic ST-segment depression in whom a non-interventional strategy is planned.*

   *There is insufficient information at this time to make any recommendations in regards to the exact location or timing for initiation of glycoprotein IIb/IIIa inhibitor therapy (i.e., ED versus inhospital).

4. What are the indications for ED administration of clopidogrel in patients with non-ST-segment elevation acute coronary syndromes?

   Exclusion Criteria: Aspirin allergy; contraindications for clopidogrel therapy (e.g., bleeding disorder, other).

   Level A recommendations. None specified.

   Level B recommendations. Administer a loading dose of clopidogrel in patients with elevated troponin or ischemic ST-segment depression*:

   1. In whom a non-interventional approach is planned
   2. Prior to percutaneous coronary intervention in patients in whom an interventional approach is planned and who are not at significant risk for urgent coronary artery bypass graft.

   Level C recommendations. None specified.

   *There is insufficient information at this time to make any recommendations in regard to the exact location or timing for administration of the initial clopidogrel loading dose (i.e., ED versus inhospital administration). Studies in elective percutaneous coronary intervention suggest benefit is greatest if clopidogrel is administered at least 6 hours prior to percutaneous coronary intervention.

Definitions:

Literature Classification Schema^

^ Some designs (e.g., surveys) will not fit this schema and should be assessed individually.

*Objective is to measure therapeutic efficacy comparing >2 interventions.

**Objective is to determine the sensitivity and specificity of diagnostic tests.

*** Objective is to predict outcome including mortality and morbidity.

Approach to Downgrading Strength of Evidence*

*See "Description of Methods Used to Analyze the Evidence" field for more information.

Strength of Recommendations

Level A recommendations. Generally accepted principles for patient management that reflect a high degree of clinical certainty (i.e., based on strength of evidence Class I or overwhelming evidence from strength of evidence Class II studies that directly address all the issues)

Level B recommendations. Recommendations for patient management that may identify a particular strategy or range of management strategies that reflect moderate clinical certainty (i.e., based on strength of evidence Class II studies that directly address the issue, decision analysis that directly addresses the issue, or strong consensus of strength of evidence Class III studies)

Level C recommendations. Other strategies for patient management based on preliminary, inconclusive, or conflicting evidence, or, in the absence of any published literature, based on panel consensus

There are certain circumstances in which the recommendations stemming from a body of evidence should not be rated as highly as the individual studies on which they are based. Factors such as heterogeneity of results, uncertainty about effect magnitude and consequences, strength of prior beliefs, and publication bias, among others, might lead to such a downgrading of recommendations.

None provided

The type of supporting evidence is identified and graded for each recommendation (see "Major Recommendations").

Not applicable: The guideline was not adapted from another source.

2006 Sep

American College of Emergency Physicians - Medical Specialty Society

American College of Emergency Physicians

Clinical Policies Subcommittee on Non–ST-Segment Elevation Acute Coronary Syndromes

ACEP Clinical Policies Committee

Clinical Policies Subcommittee (Writing Committee) on Non–ST-Segment Elevation Acute Coronary Syndromes: Francis M. Fesmire, MD (Subcommittee Chair); Wyatt W. Decker, MD; Deborah B. Diercks, MD; Chris A. Ghaemmaghami, MD; Devorah Nazarian, MD; William J. Brady, MD; Sigrid Hahn, MD; Andy S. Jagoda, MD (Clinical Policies Committee Chair)

American College of Emergency Physicians (ACEP) Clinical Policies Committee (Oversight Committee) Members: Andy S. Jagoda, MD (Chair 2003-2006); Wyatt W. Decker, MD; Jonathan A. Edlow, MD; Francis M. Fesmire, MD; Steven A. Godwin, MD; Sigrid A. Hahn, MD (EMRA Representative 2003-2004, Committee member 2005-2006); John M. Howell, MD; J. Stephen Huff, MD; JoAnn Lazarus, RN, MSN, CEN (ENA Representative 2003); Thomas W. Lukens, MD, PhD; Donna L. Mason, RN, MS, CEN (ENA Representative 2004-2006); Michael Moon, RN, CNS, MSN, CEN (ENA Representative 2004); Anthony M. Napoli, MD (EMRA Representative 2004-2006); Devorah Nazarian, MD; Scott M. Silvers, MD; Edward P. Sloan, MD, MPH; Robert L. Wears, MD, MS (Methodologist); Stephen J. Wolf, MD; John T. Finnell, II, MD, MSc (Liaison for Emergency Medical Informatics Section 2004-2006); Cherri D. Hobgood, MD (Board Liaison 2004-2006); John Skiendzielewski, MD (Board Liaison 2003-2004); Susan M. Nedza, MD, MBA (Board Liaison 2001-2003); Rhonda R. Whitson, RHIA, Staff Liaison, Clinical Policies Committee and Subcommittees

Not stated

This is the current release of the guideline.

None available

None available

This NGC summary was completed by ECRI on September 28, 2006. The information was verified by the guideline developer on January 5, 2007. This summary was updated by ECRI Institute on July 12, 2007 following the U.S. Food and Drug Administration (FDA) advisory on Troponin-1 Immunoassay.