Classification and Management of Pulmonary Hypertension

Abstract

Pulmonary arterial hypertension (PAH) is a disease characterized by progressive resistance to flow across the pulmonary vascular bed, resulting in death from progressive right heart failure. According to the most recent consensus conference, pulmonary hypertension (PH) is categorized into five maingroups. Group 1: PAH (Idiopathic, Hereditary, Drug induced, Associated with other diseases, Veno occlusive Disease); Group 2: PH associated with left sided heart diseases; Group 3: PH associated with chronic hypoxic lung diseases; Group 4: PH due to chronic thromboembolic disease; and Group 5: miscellaneous diseases of multifactorial or unclear origin, a variety of rare and not well characterized disorders1. Establishing diagnosis of PH is of utmost importance as this provides basis for making decision on management. During the 4th World Symposium (2008) on PH held in USA, new thresholdsfor mPAP (mean Pulmonary Artery Pressure) were introduced. An mPAP <21 mm Hg was defined as normal, from 21-25 mm Hg was categorized as borderline, and an mPAP >25 mm Hg was designated as manifest PH. The exercise induced pulmonary hypertension was removed from the definition.The therapy of pulmonary hypertension (PH) has changed substantially in the last 10 to 15 years. Historical survival of patients with idiopathic PH prior to availability of the pulmonary hypertension specific medications was dismal with the median life expectancy of only 2.8 years from the time of diagnosis. Current PAH specific medications, including prostanoids, endothelin receptor antagonists (ERA), and phosphodiesterase 5 inhibitors (PDE5i) have substancially changed the quality of life and survival of patients diagnosed with pulmonary arterial hypertension.