Cardiac myosin-binding protein C in ST-elevation myocardial infarction

Area of Science:

• Cardiology
• Biomarker Discovery
• Myocardial Infarction Research

Background:

• Cardiac myosin-binding protein C (cMyC) is a novel biomarker for myocardial injury.
• cMyC kinetics are faster than cardiac troponins, suggesting earlier diagnostic potential.
• Its utility in reperfused ST-segment elevation myocardial infarction (STEMI) requires evaluation against established biomarkers.

Purpose of the Study:

• To assess the correlation of cMyC with acute and final myocardial infarction (MI) size using late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR).
• To determine if cMyC levels are associated with acute microvascular obstruction (MVO) detected by CMR.
• To compare cMyC performance against high-sensitivity cardiac troponin I (hs-cTnI) and CMR findings.

Main Methods:

• Blood samples were collected for cMyC and hs-cTnI measurements at 6-hour intervals for 24 hours post-reperfusion in STEMI patients.
• Late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) was performed at approximately 3-5 days and 4 months post-reperfusion.
• Correlation and discriminatory analyses were conducted to compare cMyC and hs-cTnI with MI size and MVO.

Main Results:

• Acute cMyC levels significantly correlated with acute and final MI size, with the strongest correlation at 6 hours post-reperfusion (r=0.7).
• cMyC at 6, 12, 18, and 24 hours showed discriminatory power for acute MVO, with the 6-hour level being most effective.
• Hs-cTnI showed stronger correlations with MI size and superior discriminatory ability for MVO at later time points (12, 18, 24 hours).

Conclusions:

• cMyC serves as a quantitative biomarker of myocardial injury in reperfused STEMI.
• Further research with optimized high-sensitivity assays is needed to fully explore cMyC's potential as a novel post-MI biomarker.
• Hs-cTnI remains a stronger biomarker for assessing MI size and MVO in the early hours post-reperfusion.