We describe a 34 year old male patient with systemic lupus erythematosus (SLE) who developed pulmonary hypertension (PHT) associated with anticardiolipin antibodies. Ten years after diagnosis, an helical CT scan revealed thrombosis of the major pulmonary arteries, which was confirmed by digital pulmonary angiography. An inferior caval vein filter was placed and oral anticoagulation was begun. The patient refused pulmonary thromboendarterectomy and died soon thereafter. Even though PHT is widely described associated with SLE, proximal thrombosis of pulmonary arteries is exceptional. We describe such a patient review the different etiologies, incidence and diagnostic approach of PHT in SLE, focusing on those patients with an effective treatment.