Quantifying the Release of Biomarkers of Myocardial Necrosis from Cardiac Myocytes and Intact Myocardium.
Clin Chem
; 63(5): 990-996, 2017 05.
Article
en En
| MEDLINE
| ID: mdl-28377413
ABSTRACT
BACKGROUND:
Myocardial infarction is diagnosed when biomarkers of cardiac necrosis exceed the 99th centile, although guidelines advocate even lower concentrations for early rule-out. We examined how many myocytes and how much myocardium these concentrations represent. We also examined if dietary troponin can confound the rule-out algorithm.METHODS:
Individual rat cardiac myocytes, rat myocardium, ovine myocardium, or human myocardium were spiked into 400-µL aliquots of human serum. Blood was drawn from a volunteer after ingestion of ovine myocardium. High-sensitivity assays were used to measure cardiac troponin T (cTnT; Roche, Elecsys), cTnI (Abbott, Architect), and cardiac myosin-binding protein C (cMyC; EMD Millipore, Erenna®).RESULTS:
The cMyC assay could only detect the human protein. For each rat cardiac myocyte added to 400 µL of human serum, cTnT and cTnI increased by 19.0 ng/L (95% CI, 16.8-21.2) and 18.9 ng/L (95% CI, 14.7-23.1), respectively. Under identical conditions cTnT, cTnI, and cMyC increased by 3.9 ng/L (95% CI, 3.6-4.3), 4.3 ng/L (95% CI, 3.8-4.7), and 41.0 ng/L (95% CI, 38.0-44.0) per µg of human myocardium. There was no detectable change in cTnI or cTnT concentration after ingestion of sufficient ovine myocardium to increase cTnT and cTnI to approximately 1 × 108 times their lower limits of quantification.CONCLUSIONS:
Based on pragmatic assumptions regarding cTn and cMyC release efficiency, circulating species, and volume of distribution, 99th centile concentrations may be exceeded by necrosis of 40 mg of myocardium. This volume is much too small to detect by noninvasive imaging.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Biomarcadores
/
Miocitos Cardíacos
/
Infarto del Miocardio
/
Miocardio
Tipo de estudio:
Guideline
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Clin Chem
Asunto de la revista:
QUIMICA CLINICA
Año:
2017
Tipo del documento:
Article
País de afiliación:
Reino Unido