Pathway / Myocardial injury (shared endpoint)

Calpain

protein

Calpain mediates calcium-dependent proteolysis of cardiomyocyte structural and contractile proteins during acute myocardial ischemia and necrosis.

Pathway placement

Cascade stepMyocardial injury (shared endpoint)

Confidencemedium

RationaleCa²⁺-activated protease; cardiomyocyte ischemic proteolysis.

Druggability

Not assessed (no mapped human gene target).

Type I vs non-Type I discrimination

ScoresNon-Type-I-associated

R — rupture / Type-I

—

C — non-Type-I

A — assay feasibility

E — evidence strength

T1DI (composite)

Specificity differential (R−C)-36.9

Non-Type-I axis panel

Does this marker also move in each non-Type-I setting? mag 0–3; higher means less Type-I-specific. n/a = no evidence retrieved, which is not the same as no change.

2sepsis / systemic inflammationmag 2

2anemia / acute blood lossn/a

2hypovolemia / dehydrationmag 1

2tachyarrhythmiamag 2

2hypoxemia / respiratory failuremag 1

2hypertensive emergencyn/a

2high-demand / peri-operative stressmag 1

3sudden cardiac deathmag 2

4aPCI-related periproceduralmag 1

4bstent thrombosisn/a

4cin-stent restenosismag 2

5CABG-relatedmag 2

Coverage: 9/12 axes with evidence

Tier: deep-scored (abstract-extracted) · 21 supporting references. See the discrimination table for all markers.

Assay & specimen

Class-level default (no specific cleared assay)— generic method inferred from analyte class; confirm against a specific product insert before use.

Specimen

Serum or plasma

Collection tube

Serum separator (gold/red-top, SST) · K2/K3-EDTA (lavender-top)

Method / principle

Sandwich immunoassay (ELISA) — research-grade unless a cleared assay exists

Reagent / substrate

Matched anti-target antibody pair (capture + labeled detection)

Platform

ELISA microplate or multiplex (Luminex/MSD)

Turnaround · availability

Send-out / research · Research-grade (no universal clinical assay)

Literature evidence(1)

Degradation of troponin I in serum or plasma: mechanisms, and analytical and clinical implications.
Seminars in thrombosis and hemostasis · 2012 · PMID 22422336 · doi