Fascial reinforcement fixing the bronchi to the heart: its anatomy and clinical significance.

PURPOSE

The details of the mediastinal fascia have been scarcely described and the bronchopericardial membrane is the only known structure that is present between the bronchi and the pericardium. However, the anatomical description of this structure is unclear. This study aimed to investigate the fascial structures between the bronchi and the pericardium based on surgical findings.

METHODS

The connective tissues in the mid-mediastinum were observed surgically when lung lobectomy, including mediastinal lymph node dissection for lung cancer, was performed at our institute from April 2011 to March 2016.

RESULTS

In total, 96 lobectomies were performed in 94 patients. A firm fibrous structure connecting the tracheobronchus and the fibrous pericardium was observed. It fixes the central bronchi to the pericardium and is composed of three parts. The largest part exists in front of the carina, its appearance is membranous, and runs behind the pulmonary artery. The other parts run over the right pulmonary artery and diverge at its superior trunk. The location at which all these structures fuse to the pericardium is the venous part of the hilum cordis (VHC).

CONCLUSIONS

The results showed that connections of the dense fibrous tissues existed between the tracheobronchus and VHC. The structure not only works as a ligament that fixes the bronchi to the mid-mediastinum, but also divides the mid-mediastinum into two compartments: the Baréty and subcarinal spaces. The anatomy of the structure observed in this study differs from the previous description of the bronchopericardial membrane.