The AHA Guidelines and Scientific Statements Handbook

The AHA Guidelines and Scientifi c Statements Handbook

all patients who present with chest discomfort
consistent with ACS (see Figures 2.1, 2.2).
4 Patients with negative cardiac biomarkers within
6 h of the onset of symptoms consistent with ACS
should have biomarkers remeasured in the time
frame of 8 to 12 h after symptom onset. (Level of
Evidence: B) (see Figure 2.1).

Class IIa
1 Use of risk-stratifi cation models, such as the
Thrombolysis In Myocardial Infarction (TIMI) (see
Table 2.1) or Global Registry of Acute Coronary
Events (GRACE) risk score or the Platelet Glycopro-
tein IIb/IIIa in Unstable Angina: Receptor Suppres-
sion Using Integrilin Therapy (PURSUIT) risk
model, can be useful to assist in decision making
regarding treatment options in patients with sus-
pected ACS. (Level of Evidence: B)
2 It is reasonable to obtain supplemental ECG leads
V 7 through V 9 in patients whose initial ECG is non-
diagnostic to rule out MI due to left circumfl ex
occlusion. (Level of Evidence: B)

Class IIb

1 For patients who present within 6 h of symptoms

suggestive of ACS, a 2-h delta CK-MB mass in con-

junction with 2-h delta troponin may be considered.

(Level of Evidence: B)

2 Measurement of BNP or NT-pro-BNP may be

considered to supplement assessment of global risk in

patients with suspected ACS. (Level of Evidence: B)

c. Immediate management

Class I

1 The history, physical examination, 12-lead ECG,

and initial cardiac biomarker tests should be inte-

grated to assign patients with chest pain into one of

four categories: a noncardiac diagnosis, chronic

stable angina, possible ACS, and defi nite ACS. (Level

of Evidence: C)

2 In patients with suspected ACS in whom ischemic

heart disease is present or suspected, if the follow-up

12-lead ECG and cardiac biomarkers measurements

are normal, a stress test (exercise or pharmacologi-

cal) to provoke ischemia or a noninvasive coronary

imaging test should be performed in the ED, in a

5.7

4.1

9.0

5.8

2.2

7.3

0

1

2

3

4

5

6

7

8

9

10

OASIS 5 death,

MI, or refractory

ischemia at 9 days

OASIS 5 major

bleeding at 9 days

OASIS 5 composite

primary outcome and

major bleeding at 9 days

Absolute risk reduction

Hazard ratio

95% CI

P value

–0.1

1.01

0.90 to 1.13

0.007*

1.9

0.52

0.44 to 0.61

less than 0.001†

1.7

0.81

0.73 to 0.89

less than 0.001†

Enoxaparin

Fondaparinux

*P for noninferiority. †p for superiority. CI, confidence interval. MI, myocardial infarction.

OASIS 5, Fifth Organization to Assess Strategies for Ischemic Syndromes.

Percentage

Fig. 2.7 OASIS 5 Cumulative risks of death, MI or refractory ischemia [15].