oblique sinus (pericardial cavity, anatomy)

Last reviewed 01/2018

The oblique sinus of the pericardial cavity is a blind ending passage posterior to the heart formed by the reflections of the visceral and parietal pericardium onto the vessels traversing the space.

With the heart in its anatomical position and the dorsal pericardium intact, it forms an inverted U-shaped recess that can be probed to reveal the structures forming its walls:

• anterior: left atrium
• posterior: parietal serous pericardium
• right and inferior: visceral peritoneum on inferior vena cava
• right: 2 right pulmonary veins
• left: 2 left pulmonary veins
• superior: reflection of visceral pericardium onto wall of pericardial sac
• inferior: opening of sinus