Historical Perspective: A Century of Primary (Idiopathic) Pulmonary Hypertension.- Classification of Pulmonary Hypertension.- Diagnostic Approach to Pulmonary Arterial Hypertension.- Pathophysiology of Pulmonary Arterial Hypertension.- Pulmonary Hypertension Genes.- The Right Ventricle in Pulmonary Hypertension.- Congenital Heart Disease Associated with Pulmonary Arterial Hypertension.- Connective Tissue Disease Associated Pulmonary Hypertension.- Pulmonary Hypertension Associated with HIV, Liver Disease, Sarcoidosis, and Sickle Cell Disease.- Chronic Thromboembolic Pulmonary Hypertension.- General Therapeutic Approach and Traditional Therapies.- Prostacyclin Therapy for Pulmonary Arterial Hypertension.- Endothelin and Its Blockade in Pulmonary Arterial Hypertension.- PDE5 Inhibitors and the cGMP Pathway in Pulmonary Arterial Hypertension.- Statins for Treatment of Pulmonary Hypertension.- Transitions and Combination Therapy for Pulmonary Arterial Hypertension.- Acute Right Ventricular Dysfunction: Focus on Acute Cor Pulmonale.- Lung Transplantation and Atrial Septostomy for Pulmonary Arterial Hypertension.- New Directions in Pulmonary Hypertension Therapy.