ABSTRACT
Pulmonary hypertension (PH) comprises a spectrum of diseases characterized by elevated pulmonary artery pressure leading to right-heart failure and death (1,2). A recent clinical classification (2) distinguishes pulmonary arterial hypertension (PAH), PH due to left-heart diseases, chronic respiratory diseases, and chronic thromboembolic disease (obstructive PH). PAH includes various forms of PH of different etiologies but similar clinical presentation, and in many cases similar response to medical treatment: idiopathic PAH (IPAH), familial PAH, PAH associated with other conditions (connective tissue disease, congenital heart diseases with systemic to pulmonary shunts, portal hypertension, human immunodeficiency virus infection, and exposure to drugs and/or toxins), and PAH associated with significant venous (pulmonary veno-occlusive disease, PVOD) or capillary involvement (pulmonary capillary hemangiomatosis, PCH). Among these various causes of PAH, it is very important to distinguish PVOD because the classic treatment of PAH can induce life-threatening pulmonary edema. The diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) is also critical as this disease may be potentially curable by pulmonary thromboendarterectomy (PTE).
