Open-heart surgery requires incising the pericardium - the fluid filled sac that surrounds the heart - to access the heart. Upon completion of treatment to the heart, the pericardium should be closed. However, due to it's complex structure this is difficult to achieve. Left open or the use of synthetic material to cloe the pericardium can lead to additional issues such as scarring and adhesions, calcifications and infections. In 2011 CoreMatrix received FDA clearance for it's ECM extracellular matrix. This material provides a scaffold enabling nutrients and cells from adjacent tissues to absorb and differentiate into tissue-specific cells. The result is that as new cells are created and build, the ECM matrix is resorbed and replaced by functional tissue as opposed to injured and scarred tissue. In the case of the pericardium, this means that an ECM matrix 'patch' can be sutured to the pericardium over the incision area and wth time and using the matrix to build upon, the matrix is absorbed and what is left is an intact, organized, healthy and functional pericardium.