Pulmonary venoocclusive disease

Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension caused by progressive blockage of the small veins in the lungs. The blockage raises the blood pressure in the pulmonary arteries, which in turn leads to heart failure. The disease is progressive and fatal, with a median survival of about two years from diagnosis, and the definitive therapy is lung transplantation. Mutations in the EIF2AK4 gene are the genetic cause, and viral infection and toxic chemicals such as chemotherapy drugs are other possible contributors. A firm diagnosis generally needs a lung biopsy, although CT scans can show suggestive findings such as ground-glass opacities and enlarged mediastinal lymph nodes. Treatments used for primary pulmonary hypertension, such as prostacyclins and endothelin receptor antagonists, can be dangerous in PVOD because they may cause severe pulmonary edema. The disease is rare and probably often misdiagnosed as idiopathic pulmonary arterial hypertension, it affects men and women about equally, and it has been reported after bone marrow transplantation and with several chemotherapy regimens.