FINDINGS:
Portable semi-upright radiograph of the chest demonstrates low lung volumes,
 which results in bronchovascular crowding. There has been interval removal of
 the endotracheal tube, nasogastric tube, two mediastinal drainage catheters,
 and epicardial pacing wires.  The cardiac portion of the mediastinum is
 moderately larger and a much larger triangular gas and debris collection
 projecting over the left lower lobe bronchus could be in the stomach,
 esophagus, mediastinum or pericardium. . The left hemidiaphragm is
 asymmetrically elevated. There is some left lower lobe atelectasis. No
 pneumothorax.

IMPRESSION:
Air and debris collection it could be in the pericardium, mediastinum, or in
 the esophagus or herniated stomach. Recommend PA and lateral radiographs of
 the chest for further evaluation.