Unilateral pulmonary edema. An unusual cause.

A patient presented with shortness of breath without fever, cough or sputum production. The patient was hypoxic without leukocytosis and a chest x-ray film demonstrated a right unilateral pulmonary infiltrate. A chest CT showed a large ascending thoracic aortic aneurysm with dissection. During surgical repair, the aneurysm was noted to be compressing the single right pulmonary vein. The infiltrate resolved postoperatively, and the patient has remained symptom-free for one year.