Arq. Bras. Cardiol. 2024; 121(12): e20240735

Challenges and Perspectives of Cardiac Fibrosis Biomarkers: From Diagnosis to Clinical Application

Priscila Portugal dos Santos , Ricardo Luiz Damatto

DOI: 10.36660/abc.20240735i

This Short Editorial is referred by the Research article "Potential Biomarkers in Myocardial Fibrosis: A Bioinformatic Analysis".

As reported by Cheng-Mei et al. myocardial fibrosis is present in various cardiac diseases and can negatively impact the heart. It plays a central role in cardiac dysfunction and failure across different pathologies, serving as a strong predictor of poor clinical outcomes and mortality. However, it is essential to recognize that fibrosis is a complex and heterogeneous process, which can sometimes play a beneficial role, such as after a myocardial infarction. In this context, fibrosis acts as a reparative mechanism, replacing dead cardiomyocytes with scar tissue. This initial fibrotic response is crucial to prevent cardiac rupture, a severe and often fatal complication and one of the leading causes of death in patients with acute myocardial infarction.

Cardiac fibrosis is characterized by the excessive accumulation of extracellular matrix (ECM) components, especially collagens, within the myocardium. Understanding this process involves more than just collagen quantity; the characterization of fibrosis also considers collagen quality, the ratio of different fiber types, and the degree of collagen cross-linking. Type I collagen, which predominates in cardiac and vascular ECM, contributes to tissue strength and stiffness due to its thick, dense structure. Type III collagen, being more flexible, aids in ECM compliance. Thus, myocardial elasticity is determined by the ratio of type I to type III collagen fibers.^, Moreover, the degree of covalent cross-linking among the constituent microfibrils is critical to collagen fiber rigidity, increasing their resistance to degradation and significantly contributing to tissue stiffening.^, Therefore, a comprehensive understanding of cardiac fibrosis, aimed at developing new therapies and diagnostic methods, requires evaluating collagen quantity, quality, and cross-linking levels.

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