Images in Cardiovascular Medicine Long-Term Survivor With Pulmonary Veno-Occlusive Disease

51-year-old woman was admitted to our hospital becauseofshortnessofbreath.Hermeanpulmonaryarterypressurewas 52 mm Hg, and idiopathic pulmonary artery hypertensionwas diagnosed. She received beraprost sodium, imidapril, war-farin, and home-based oxygen therapy. At 67 years of age,dyspnea on effort worsened to New York Heart Associationfunctional class III. The plasma level of brain natriuretic peptidewas 57 pg/mL. Transthoracic echocardiography showed anenlarged right ventricle, severe tricuspid regurgitation, and alarge pericardial effusion. At 68 years of age, she was urgentlyadmitted to our hospital because of severe dyspnea at rest. Achest x-ray showed bilateral pulmonary artery enlargement(Figure1).Computedtomographyofthechestrevealedthatbothmain bronchi were compressed by the pulmonary artery aneu-rysms,withnomuralthrombusinthepulmonaryarteries(Figure2). The diameters of the right and left main pulmonary arterieswere 69.8 and 55.5 mm, respectively. Bronchoscopy duringmechanical ventilation confirmed nearly complete extrinsiccompression of the left and right main stem bronchi withoutpositive airway pressure (Figure 3). On hospital day 3, contin-uous administration of epoprostenol was begun. She receivedcontinuous positive airway pressure by mechanical ventilation.Because the pulmonary hypertension had been worsening, treat-ment with imatinib (50 mg/d) was started on hospital day 69.However,thepatientdiedofrecurrentobstructivepneumonia12months after admission, and autopsy was conducted.Histopathologically, pulmonary arteries/arterioles revealeddilatation, and alveolar walls were thickened with increasedcapillaries, deposition of hemosiderin, and loose fibrosis(Figure 4a and 4b). However, severe concentric medialhypertrophy,intimalfibrousthickening,andplexiformlesion,which are characteristic findings of idiopathic pulmonaryarteryhypertension,werenotfoundinthepulmonaryarteries/arterioles (Figure 4a and 4b). Normal pulmonary veins in thethickened interlobular septa mostly disappeared, and capillar-ies increased instead (Figure 4c and 4d).The pulmonary veins might have been destroyed during theprolongeddiseasecourse.Enlargedbronchialveins(Figure5)probably served as collateral vessels of the occluded pulmo-nary veins. On reviewing the computed tomography scansobtained at the patient’s initial admission, we found ground-glass opacities and smooth thickened intralobular septa,which are characteristic features of pulmonary veno-occlusive disease (PVOD; Figure 6).