What is the consequence of an increase in fibroblasts within cardiac tissue?

An increase in fibroblasts within cardiac tissue leads to increased myocardial stiffness and fibrosis. Fibroblasts are a type of cell crucial for the maintenance and structural integrity of the extracellular matrix in the heart. When there is an increase in these cells, they contribute to the production of collagen and other extracellular matrix proteins, leading to a thickening and stiffening of the myocardial tissue. This process is often a response to damage or stress in the heart, such as that seen in heart failure.

As the extracellular matrix becomes more dense and fibrotic, the heart's ability to relax and fill with blood during diastole can be compromised, contributing to heart failure's symptoms. Thus, the stiffening of the myocardium due to excessive fibrosis disrupts normal heart function and worsens heart failure, making the connection between increased fibroblast activity and adverse outcomes in cardiac tissue very clear.