Introduction:
Cystic echinocccosis also known as hydatid cyst is caused by tapeworm of the echinococcus type; The cysts most commonly found in liver (70%), lung (20%) and in other organs such as spleen and kidney (10-15%).1, 2 Cardiac and cerebral involvements by the hydatid disease are rarely reported. Regarding pulmonary artery, there are few reports on intramural involvement of pulmonary artery, with subsequent obstructive symptoms such as chronic exertional dyspnea.1 These cysts are the result of disseminated larvae of the parasite from other primary sites such as lung that enter bloodstream (secondary echinococcosis). To our knowledge in the previous literature no reports of primary extra luminal hydatic cyst with signs and symptoms of pulmonary artery compression and stenos have been made.