Traumatic rupture of the pericardium with a peculiar chest radiographic finding

A 46-year-old man was admitted because of progressive exertional dyspnea and pulsating neck vein for 3 years. He had a history of car accident with his chest struck by the steering wheel 10 years previously. Physical checkup and laboratory studies revealed severe tricuspid regurgitation. The chest radiography disclosed mild cardiomegaly and shift of the heart towards the left hemithorax with a bizarre cardiac silhouette showing double contour over the left ventricular border, suggesting the possibility of partial absence of the left pericardium. The latter diagnosis was confirmed at open heart surgery for the associated severe tricuspid regurgitation.