Creatine kinase-MB

protein

Creatine kinase-MB is released from necrotic cardiomyocytes, quantifying the extent of myocardial necrosis in acute myocardial infarction.

Pathway placement

Cascade stepMyocardial injury (shared endpoint)

Confidencehigh

RationaleCardiac-specific isoenzyme marking cardiomyocyte necrosis and infarct size; anchor for myocardial injury endpoint.

Druggability

Not assessed (no mapped human gene target).

Type I vs Type II discrimination

ScoresShared / rises in both

R — rupture / Type-I

100

C — confounder / Type-II

A — assay feasibility

E — evidence strength

T1DI (composite)

Specificity differential (R−C)+45.3

Direct evidence: higher in Type I (D=+1)

CK-MB rises in both T1MI and T2MI; pattern comparison shows T1MI elevation

Confounder panel (Type-II drivers)

1sepsis / systemic inflammationn/a

2anemia / acute blood lossn/a

3hypovolemia / dehydrationmag 2

4tachyarrhythmian/a

5hypoxemia / respiratory failuremag 2

6hypertensive emergencyn/a

7high-demand / peri-operative stressmag 2

Coverage: 3/7 confounders with evidence

Tier: deep-scored (abstract-extracted) · 7 supporting references. See the discrimination table for all markers.

Validated clinical assay

Specimen

Serum or plasma

Collection tube

Serum separator (gold/red-top, SST) · Lithium heparin (green-top)

Method / principle

Chemiluminescent sandwich immunoassay (mass); or enzymatic activity

Reagent / substrate

Anti-CK-MB antibody pair (mass); or CK-MB immunoinhibition + coupled hexokinase/G6PD (activity)

Platform

Automated core-lab analyzer

Turnaround · availability

STAT–routine · FDA-cleared