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A congenital arteriovenous malformation originating from the aorta locating in the posterior mediastinum.

Vascular malformations located in the posterior mediastinum are extremely rare. Most of them are found coincidentally during routine examinations. Only a small percentage of these posterior mediastinal arteriovenous malformation cases may cause symptoms such as dyspnea due to compression of surrounding tissues. Radiologic imaging can be insufficient in some cases for differential diagnosis. Because of their vascular nature, diagnostic needle biopsy may have a high risk of bleeding. Open surgical resection is a safe treatment choice under many circumstances, and it helps the diagnosis as well. In this paper, a case of a 31-year-old male is presented with an incidentally diagnosed arteriovenous malformation, originating from the descending aorta and located in the posterior mediastinum.