Pulmonary artery intimal sarcoma masquerading as pulmonary embolism.

A 33-year-old man noted increasing dyspnea over a period of 6 weeks. Initial evaluation with transthoracic echocardiography demonstrated severe right ventricular dilation and systolic contractile dysfunction along with moderately severe tricuspid valve regurgitation on color Doppler with an estimated right ventricular systolic pressure of 108 mm Hg based on continuous wave Doppler assessment of the tricuspid regurgitant jet (Figure 1 and online-only Data Supplement Movies I and II). Subsequent evaluation for the cause of pulmonary hypertension included contrast-enhanced computed tomography of the chest that demonstrated a large homogeneous filling defect within the main pulmonary artery extending into the proximal right and left branches (Figure 2). Bilateral lower-extremity venous duplex scan was negative for acute deep venous thrombosis. Intravenous thrombolytics were subsequently administered without change in size of the pulmonary artery filling defect on follow-up chest computed tomography performed the next day. Cardiac magnetic resonance imaging demonstrated a mildly expansile, heterogeneous, partially enhancing mass (Figure 3 and online-only Data Supplement Movie III). The patient underwent surgical resection of a large, fleshy tumor within the main pulmonary artery. The tumor was attached to the main pulmonary artery and had invaded through the wall. The pulmonary valve was replaced with a homograft. Histological examination revealed a high-grade intimal sarcoma with osteosarcomatous differentiation (Figure 4). The patient was discharged from the hospital 1 week after surgery with plans to follow-up with oncology as an outpatient.