Compression of the right pulmonary artery by aortic aneurysms: CT demonstration

Compression of the right pulmonary artery by a massive descending aortic aneurysm causing bilateral perfusion defects on pulmonary scintigraphy

A 67-year-old woman, who presented with a 2 month history of dyspnea, had a ventilation and perfusion lung scan that showed absent perfusion of the entire right lung with normal ventilation, as well as a rounded matched defect in the left lower lung adjacent to midline, suspicious for an aortic aneurysm or dissection. CT pulmonary angiography revealed a massive descending aortic aneurysm compressing the right pulmonary artery as well as the left lung parenchyma, accounting for the bilateral perfusion scan defects. We present the Xe-133 ventilation, Tc-99m MAA perfusion and CT pulmonary angiography imaging findings of this rare case.

Breathlessness and a widened mediastinum

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Right ventricular obstruction in aortic dissection: a mechanism of hemodynamic collapse

The main and right pulmonary arteries may be compressed by the false lumen of a type I aortic dissection. We report a 73-year-old women with a dissection of the aorta in whom echocardiographic examination revealed acute pulmonary arterial compression causing right ventricular failure and hemodynamic collapse.