Publication

Evaluating the utility of circulating biomarkers of collagen synthesis in hypertrophic cardiomyopathy

Journal Paper/Review - Jan 30, 2014

Units
PubMed
Doi

Citation
Ellims A, Taylor A, Mariani J, Ling L, Iles L, Maeder M, Kaye D. Evaluating the utility of circulating biomarkers of collagen synthesis in hypertrophic cardiomyopathy. Circ Heart Fail 2014; 7:271-8.
Type
Journal Paper/Review (English)
Journal
Circ Heart Fail 2014; 7
Publication Date
Jan 30, 2014
Issn Electronic
1941-3297
Pages
271-8
Brief description/objective

BACKGROUND
In hypertrophic cardiomyopathy (HCM), accumulation of myocardial collagen may play a central role in the pathogenesis of diastolic dysfunction and arrhythmia. Previous studies have suggested that peripheral levels of byproducts of collagen synthesis are reflective of myocardial extracellular matrix metabolism, although this has not been validated in detail. Given the potential clinical utility of such biomarkers, we sought to validate the assumed relationship between peripheral markers and myocardial fibrosis in HCM.

METHODS AND RESULTS
Fifty patients with HCM and 25 healthy controls underwent peripheral venous sampling to determine plasma concentrations of key collagen precursors (procollagen I and III N-terminal propeptides [PINP, PIIINP]). Contrast-enhanced cardiac magnetic resonance imaging was performed to quantify regional (by late-gadolinium enhancement) and diffuse (by T1 mapping) myocardial fibrosis. Nineteen subjects also underwent simultaneous arterial and coronary sinus blood sampling (to derive transcardiac concentration gradients of PINP, PIIINP, and C-terminal telopeptide of type I collagen) and right heart catheterization. Despite cardiac magnetic resonance evidence of regional (late-gadolinium enhancement quantity, 6.4±8.0%) and diffuse (T1 time, 478±79 ms) myocardial fibrosis in patients with HCM, peripheral levels of collagen precursors were similar compared with control subjects (PINP, 45.9±22.9 versus 53.4±25.9 μg/L; P=0.21; PIIINP, 4.8±1.7 versus 4.4±1.1 μg/L; P=0.26). No significant net positive transcardiac concentration gradient was detected for either biomarker of collagen synthesis.

CONCLUSIONS
The cardiac contribution to peripheral levels of byproducts of collagen synthesis in patients with HCM is insignificant. Furthermore, peripheral levels of these biomarkers do not accurately reflect myocardial collagen content in these patients.