2016 Volume 27 Issue 1 Pages 21-26
A 72-year-old man who suffered from chronic thromboembolic pulmonary hypertension (CTEPH) for 6 years and treated by medication was admitted to undertake pulmonary endarterectomy (PEA). His pulmonary artery pressure and pulmonary vascular resistance before the operation were 75/28 (48) mmHg and 701 dyn/s/cm−5, respectively. Neither thrombotic predisposition nor deep vein thrombosis was detected. PEA was performed and the broad intima of the right pulmonary trunk along with massive organized thrombi were successfully extracted. He became hemorrhagic from the right respiratory tract during the operation and died from progressive pleural effusion at 85 days postoperation. Autopsy showed severe hypertrophy of the right ventricular muscle. The right pulmonary artery showed the central type of CTEPH. At the pulmonary trunk, the intima was broadly dissected and secondary thrombi were partially adherent to the dissected lumen. Some muscular arteries formed vein-like lesions, especially at the peripheral side of the completely occluded proximal artery. In contrast, the left pulmonary artery showed the peripheral type of CTEPH. At the left pulmonary artery, the intima was well preserved in the pulmonary trunk and a “band and web-like appearance” was broadly observed at various sizes of arteries from lobar to small elastic arteries. Intimal thickening and organized thrombi were observed at peripheral muscular arteries. The vein-like lesion was a specific finding of sustained pulmonary hypertension. In cases of CTEPH, vein-like lesions are thought to occur by severe obstruction of the proximal artery. These lesions suggest a poor prognosis, resulting in alveolar hemorrhage after PEA.
