What is transverse sinus pericardium?

The transverse sinus of the pericardium is a cavity located posteriorly to the ascending aorta and the pulmonary trunk and anteriorly to the superior vena cava. It is a potential space within the pericardial sac that forms a channel-like structure between the left and right sides of the heart. The transverse sinus is formed by the reflection of the pericardium between the arterial and venous blood vessels and allows for the free movement of the heart during contraction and relaxation. In certain surgical procedures, such as the placement of pacemakers and the removal of tumors, the transverse sinus can be used for safe access to the heart.