Pulmonary atelectasis from compression of the left main bronchus by an aortic aneurysm.

Pulmonary atelectasis may be caused by endobronchial lesions or by extrinsic compression of the bronchus. However, lung collapse due to compression from a thoracic aneurysm is uncommon. We report a 76-year-old hypertensive female patient who has pulmonary atelectasis due to an extrinsic compression from a descending thoracic aortic aneurysm, and discuss possible treatment options.