Antiphospholipid antibodies in chronic thromboembolic pulmonary hypertension.

Acquired thrombophilia and in particular the presence of antiphospholipid antibodies (aPL) may play an important role in the development of chronic thromboembolic pulmonary hypertension (CTEPH). Young patients suffering from an episode of unprovoked pulmonary embolism (PE), or PE provoked by mild risk factors, should be tested for aPL. In case of a positive result, they should be closely followed up and lifelong anticoagulant treatment should be considered. Indeed, aPL-induced thrombophilia may favor PE recurrence with the consequence of possible CTEPH development. The aPL profiles play an important role in this pathway. Patients with PE and triple positivity (lupus anticoagulant, LAC, anti-cardiolipin, aCL, and anti-β2-glycoprotein I, aβ2GPI) are at the highest risk of recurrence and deserve maximum protection by anticoagulant treatment with warfarin.