Painless left hemorrhagic pleural effusion: An unusual presentation of dissecting ascending aortic aneurysm.

Aortic dissection is a catastrophic event that is commonly associated with severe pain, massive hemorrhage, and high mortality. In this report, we present the case of a 31-year-old man who presented with painless, hemorrhagic left pleural effusion. Further investigation revealed a 9-cm dissecting ascending aortic aneurysm that was thought to be due to a congenitally bicuspid aortic valve. We suggest that ascending aortic aneurysm be included in the differential diagnosis of hemorrhagic pleural effusion, even in the absence of the classic features of aortic dissection, such as chest pain, advanced age, or history of hypertension.