[Hemothorax due to Idiopathic Rupture of Pulmonary Artery with Defect of Tunica Media].

A 47-years-old man with hemodynamic shock was refered to our hospital by an ambulance. Chest computed tomography(CT)showed left hemothorax and the extravasation of contrast media in his left lung. Emergency operation was done. A lot of intrathoracic hematoma and pulsating bleeding from the lung was found, and lingular segmentectomy was performed. Pathologically, the rupture of pulmonary artery of 2.2 mm in diameter was found without the finding of imflammation nor degeneration due to any basal diseases. Around the lesion, some artery of 0.3~3.0 mm in diameter showed defect of tunica media. This vascular anomaly was considered to lead his hemothorax.