Primary antiphospholipid syndrome and pulmonary hypertension.

Primary antiphospholipid syndrome (APS) is a disease characterized by the presence of autoantibodies reacting with proteins bound to phospholipids, leading to thrombosis and gestation abnormalities. Prothrombotic states and impaired clot dissolution are believed to contribute to the occurrence of chronic thromboembolic pulmonary hypertension (CTEPH) in APS. Whether preventive anticoagulation therapy in patients with antiphospholipid autoantibodies without a history of thrombosis reduces the risk of thrombosis is currently unclear. The diagnosis and treatment of CTEPH in APS is similar to CTEPH complicated by other predisposing conditions, with surgical treatment being the most effective. However, not every patient with CTEPH is suitable for pulmonary thromboendartarectomy and such individuals may benefit from pharmacotherapy of pulmonary hypertension, given the presence of pulmonary microvascular abnormalities similar to those in idiopathic pulmonary hypertension. Anticoagulation therapy is the mainstay of management because of the high risk of recurrent embolization and local in-situ thrombosis.