Page 1701 - Saunders Comprehensive Review For NCLEX-RN

1. Troponin level: Level rises within 3 hours and remains
elevated for up to 7 to 10 days.
2. Total CK level: Level rises within 6 hours after the
onset of chest pain and peaks within 18 hours after
damage and death of cardiac tissue.
3. CK-MB isoenzyme: Peak elevation occurs 18 hours
after the onset of chest pain and returns to normal 48
to 72 hours later.
4. Myoglobin: Level rises within 2 hours after cell death,
with a rapid decline in the level after 7 hours.
5. White blood cell count: An elevated white blood cell
count appears on the second day following the MI
and lasts up to 1 week.
6. Electrocardiogram
a. ECG shows either ST segment elevation
MI (STEMI), T-wave inversion, or
NSTEMI; an abnormal Q wave may
also present.
b. Hours to days after the MI, ST- and T-
wave changes will return to normal,
but the Q-wave changes usually
remain permanently.
7. Cardiac catheterization may be done emergently to
determine the extent and location of obstructions of
the coronary arteries; this allows for use of PTCA and
restoration of bloodflow to the myocardium.
8. Diagnostic tests following the acute stage
a. Exercise tolerance test or stress test to
assess for electrocardiographic changes
and ischemia and to evaluate for
medical therapy or identify clients who
may need invasive therapy.
b. Thallium scans to assess for ischemia or
necrotic muscle tissue.
c. Multigated cardiac blood pool imaging
scans may be used to evaluate left
ventricular function.
d. If not done urgently, cardiac
catheterization to determine the
coronary artery obstructions will be
done after the client is stabilized.

E. Assessment

1. Pain
a. Client may experience crushing
substernal pain.
b. Pain may radiate to the jaw, back, and
left arm.

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