Cardiac Cell System

The cardiac fibroblasts (CF) are the principal cell type of the heart. They provide structural support for cardiac myocytes and are responsible for extracellular matrix synthesis in the heart during growth and pathophysiological conditions. CF are an important cellular component of myocardial responses to injury and the source of paracrine growth factors. They are also responsible for scar formation.

The cardiac myocyte is the most physically energetic cell in the body. Its contraction is myogenic, i.e. it is independent of nervous stimulation. Cardiac myocytes occupy as much as 75% of cardiac mass but constitute only about one third of the total cell number in the heart. Cardiac myocyte hypertrophy and apoptosis have been implicated in the loss of contractile function during heart failure. Cardiac myocytes have a complex network of signals that regulates their essential role in the rhythmic pumping of the heart.