CREATINE KINASE MB FRACTION (CK-MB), PLASMA

 

 

Synonyms:

CK-MB

Lab Test Code:

CKMB

Test Performed In:

Chemistry (Rapid Response)

Test Methodology:

Chemiluminescence

Reported:

STAT - 60 minutes

Routine: 2 - 4 hours

Test Set Up Frequency: Daily (Monday-Friday)

Patient Preparation:

 

Specimen Requirements:

Collect: 4 mL blood in light green-top (lithium heparin) tube(s), or send 1 mL of plasma refrigerated or frozen.

Transport: Refrigerated

Minimum volume: 1 mL plasma

Rejection Criteria: Specimens received beyond stated stability

Specimen Stability: After separation from cells: Ambient: 8 hours; Refrigerated: 12 hours; frozen: 24 hours.

Reference Values:

CKMB > 5 RI > 2.5:  Strongly suggests myocardial involvement

CKMB > 5 RI < 1:  Suggests skeletal muscle involvement

CKMB > 5 RI > 1 but < 2.5:  Uncertain; requires a second specimen 4-8 hours later

CKMB < 5 RI > 2.5:  Suggests early myocardial infarction or chronic renal, pulmonary, or hepatic disease, or could be within normal range. Investigation of myocardial infarction requires second specimen 4 to 8 hours later.

CKMB < 5 RI < 2.5:  Normal range

Note:

1.      After non-recurrent myocardial infarction (MI), CKMB levels increase typically 3 to 6 hours after onset of chest pain and return to normal after 48 to 72 hours. Multiple CKMB determinations 4 to 8 hours apart provide the most detailed information.

2.      This will confirm peaks (approximately 16 hours) and the fall of CKMB following MI.

3.      When there is a combination myocardial and skeletal muscle injury, caution is suggested in interpreting results (CKMB > 5, RI equal to approximately 1.0).

Additional Information:

 

CPT Code(s):

82550, 82553