Oblique pericardial sinus

The oblique pericardial sinus is a blind-ending pericardial cul-de-sac behind the heart which opens into the pericardial space proper inferiorly.

Gross anatomy

Its boundaries are:

  • right (in ascending order): inferior vena cava, right inferior pulmonary vein and right superior pulmonary vein
  • superior: it is separated from the transverse pericardial sinus above by a double reflection of serous pericardium that extends transversely between the left and right superior pulmonary veins
  • left (in ascending order): left inferior pulmonary vein and left superior pulmonary vein

Anteriorly lies the heart, specifically the posterior wall of the left atrium and posteriorly the pericardium and esophagus.

Several pericardial recesses form small pockets that may extend from or towards the oblique sinus, which may mimic mediastinal lymph nodes or disease: