The AHA Guidelines and Scientific Statements Handbook

Chapter 3 ST-Elevation Myocardial Infarction

angina, MI, CABG, or PCI. Evaluation of the patient’s
complaints should focus on chest discomfort, associ-
ated symptoms, sex- and age-related differences in
presentation, hypertension, diabetes mellitus, possibil-
ity of aortic dissection, risk of bleeding, and clinical
cerebrovascular disease (amaurosis fugax, face/limb
weakness or clumsiness, face/limb numbness or sensory
loss, ataxia, or vertigo). (Level of Evidence: C)

2. Physical examination (Table 3.1)
   Class I
   1 A physical examination should be performed to
   aid in the diagnosis and assessment of the extent,
   location, and presence of complications of STEMI.
   (Level of Evidence: C)
   2 A brief, focused, and limited neurological exami-
   nation to look for evidence of prior stroke or cogni-
   tive defi cits should be performed on STEMI patients
   before administration of fi brinolytic therapy. (Level
   of Evidence: C)


3. Electrocardiogram
   Class I
   1 A 12-lead ECG should be performed and shown
   to an experienced emergency physician within 10
   minutes of ED arrival for all patients with chest dis-
   comfort (or anginal equivalent) or other symptoms
   suggestive of STEMI. (Level of Evidence: C)
   2 If the initial ECG is not diagnostic of STEMI but
   the patient remains symptomatic, and there is a high
   clinical suspicion for STEMI, serial ECGs at 5- to
   10-minute intervals or continuous 12-lead ST-
   segment monitoring should be performed to detect
   the potential development of ST elevation. (Level of
   Evidence: C)

3 In patients with inferior STEMI, right-sided ECG

leads should be obtained to screen for ST elevation

suggestive of right ventricular (RV) infarction. (See

Section 7.6.6 of the full-text guidelines and the ACC/

AHA/ASE 2003 Guideline Update for the Clinical

Application of Echocardiography.) (Level of Evi-

dence: B)

4. Laboratory examinations
   Class I
   Laboratory examinations should be performed as
   part of the management of STEMI patients but
   should not delay the implementation of reperfusion
   therapy. (Level of Evidence: C)


5. Biomarkers of cardiac damage
   Class I
   1 Cardiac-specifi c troponins should be used as the
   optimum biomarkers for the evaluation of patients
   with STEMI who have coexistent skeletal muscle
   injury. (Level of Evidence: C)
   2 For patients with ST elevation on the 12-lead ECG
   and symptoms of STEMI, reperfusion therapy should
   be initiated as soon as possible and is not contingent
   on a biomarker assay. (Level of Evidence: C)

Class IIa

Serial biomarker measurements can be useful to

provide supportive noninvasive evidence of reperfu-

sion of the infarct artery after fi brinolytic therapy in

patients not undergoing angiography within the fi rst

24 hours after fi brinolytic therapy. (Level of Evi-

dence: B)

Class III

Serial biomarker measurements should not be relied

on to diagnose reinfarction within the fi rst 18 hours

after the onset of STEMI. (Level of Evidence: C)

a. Bedside testing for serum cardiac biomarkers

Class I

1 Although handheld bedside (point-of-care) assays

may be used for a qualitative assessment of the pres-

ence of an elevated level of a serum cardiac bio-

marker, subsequent measurements of cardiac

biomarker levels should be performed with a quan-

titative test. (Level of Evidence: B)

2 For patients with ST elevation on the 12-lead ECG

and symptoms of STEMI, reperfusion therapy

Table 3.1 Brief physical examination in the Émergency
Department

1. Airway, Breathing, Circulation (ABC)


2. Vital signs, general observation


3. Presence or absence of jugular venous distension


4. Pulmonary auscultation for rales


5. Cardiac auscultation for murmurs and gallops


6. Presence or absence of stroke


7. Presence or absence of pulses


8. Presence or absence of systemic hypoperfusion (cool, clammy,
   pale, ashen)