Pulmonary vascular pathology forms an important challenge in daily clinical practice; pulmonary embolism (PE) is the third leading cause of cardiovascular mortality in North America and is responsible for 5-10% of all in-hospital deaths. Furthermore, the diagnosis of PE remains one of the most difficult problems confronting clinicians. Timely diagnostic testing must be performed to enable the initiation of antithrombotic therapy for patients proven to have this condition while avoiding the risks of anticoagulation for patients without PE. The widespread adoption of right heart catherisation in the 1950s, for the study of heart and lung disease in humans, allows identification of patients suffering from pulmonary hypertension (PH). In case of exclusion of other causes of PH, this unexplained PH is designated as primary. The present monograph "Pulmonary Vascular Pathology: A Clinical Update" reviews the current knowledge in this field of pulmonary medicine. In particular, a better understanding of the actual pathogenesis of these pathologies offers perspectives of optimism in the future management of these patients.