Cardiomyocytedominated

Cardiomyocytedominated describes a tissue composition in which cardiomyocytes are the predominant cell type relative to other cardiac resident cells. The term is used especially in discussions of heart tissue, cardiac muscle constructs, and regenerative models to indicate that the contractile, electrically active cells make up the major share of cells and tissue mass.

In the healthy mammalian heart, cardiomyocytes are the principal contractile unit and drive systolic function, while nonmyocytes such as fibroblasts, endothelial cells, smooth muscle cells, and resident immune cells are present in substantial numbers and provide structural support, vasculature, and paracrine interactions. The precise proportion of cardiomyocytes versus nonmyocytes varies by species, developmental stage, region, and measurement method, and is not identical across all contexts.

In tissue engineering and regenerative medicine, cardiomyocytedominated constructs aim to recapitulate native myocardium by enriching for cardiomyocytes, often derived from pluripotent stem cells. Achieving true dominance is challenging because supporting cell types and vascularization are needed for maturation and function.

In pathology, myocardial injury often leads to loss of cardiomyocytes and replacement by fibrous tissue; such scar tissue is noncardiomyocytedominated and correlates with impaired contractile function. Conversely, therapies that preserve or restore cardiomyocytes seek to re-establish cardiomyocytedominated tissue to recover function.

Assessment methods include histology with cardiomyocyte markers (e.g., cardiac troponin I or T, alpha-actinin) versus nonmyocyte markers, immunohistochemistry, and single-cell transcriptomics to quantify cell-type proportions.