The Macklin effect causing a pneumopericardium.

Pleuropericarditis is a common clinical entity that has been reported in association with several diseases. However, pleuropericarditis following blunt thoracic trauma is very rare and difficult to diagnose. Here we present a case of a young man who presented to the emergency department with acute shortness of breath following a motor vehicle accident. He was found to have a pleuro-pericardial communication worsened by barotrauma, resulting in tension pneumopericardium.