The extracellular matrix plays an important role in biological processes, for example cellular adhesion, proliferation, migration and differentiation. Many of the cell-cell and cell-matrix interactions are mediated by extracellular matrix components and by their respective membrane receptors. Important pathophysiological processes occur through these interactions of which ontogenesis tissue differentiation and reconstruction, many inflammatory and immunological events and metastatic processes and invasion. The myocardium is made of muscular, vascular and connective components that exist in a state of equilibrium based on their relative proportions, integral structures, and on their physical and chemical characteristics. The Authors have described molecular events that lead to the organization of the cardiac tissue in physiological conditions and to its reorganization in pathological situation. Furthermore they have evaluated the role of fibronectin, a glycoprotein of the extracellular matrix in the initial phase of cardiac ischemia.