Complete left-sided absence of the pericardium in association with ruptured type A aortic dissection complicated by severe left hemothorax.

We report an unusual clinical presentation of an acute type A aortic dissection as a left hemothorax in a patient with a congenital pericardial defect. Although the pericardial defect was diagnosed preoperatively, we could not exclude the possibility of a ruptured descending aorta until we discovered the site of the rupture during operation. The presence of a pericardial defect would at first appear to be a fatal disadvantage in such a situation as this, due to massive bleeding into the pleural space; but we believe that in our patient spontaneous drainage of blood into the pleural cavity prevented severe cardiac tamponade. The only reason for his deteriorating hemodynamic status was hypovolemia, which was corrected with volume replacement.