Pulmonary hypertension due to chronic pulmonary thromboembolism is frequently underdiagnosed and has a very poor prognosis if untreated. When the presence of central pulmonary artery thrombus is confirmed, thromboendarterectomy is the treatment of choice, with very good results. We report a 28 years old male with two previous episodes of deep venous thrombosis (DVT) who was admitted due to 8 months of progressive shortness of breath and a syncope. He underwent a CT pulmonary angiogram and an echocardiogram. Severe pulmonary hypertension was confirmed, secondary to a chronic pulmonary thromboembolism with an overlapped acute component. He received systemic thrombolysis with partial thrombus disappearance. Therefore a pulmonary thromboendarterectomy was performed and an inferior vena cava filter was placed. The patient was discharged with marked improvement in his functional capacity.