Biomarkers of extracellular matrix turnover.

The extracellular cardiac matrix (ECCM) plays an important role in the support of myocytes and fibroblasts. ECCM turnover is influenced by ischemia, stretch, inflammation, and neurohormonal mediators. Myocardial fibrosis is the consequence of several pathologic processes mediated by mechanical, neurohormonal, and cytokine factors. It is a major determinant of diastolic dysfunction and pumping capacity and may result in tissue heterogeneity, dys-synchrony, and arrhythmias. The measurement of various serum peptides arising from the metabolism of collagen types 1 and 3, of degradation fragments, and of specific metalloproteinases may provide noninvasive assessment of fibrosis. ECCM biomarkers are clinically useful tools, particularly given the potential for cardioprotective and cardioreparative pharmacologic strategies.