Treprostinil

Pulmonary hypertension (PH) is a progressive disease that if left untreated, has very high morbidity and mortality due to right-sided heart failure. Pulmonary hypertension falls into five separate World Health Organization (WHO) groups based on the etiology, which has important ramifications for subsequent management. Group 1 is pulmonary arterial hypertension (PAH). PAH can be due to genetic causes, connective tissue diseases, HIV, schistosomiasis, portal hypertension or drugs and toxins. Group 2 is PH due to left heart disease. Group 3 is PH due to chronic lung disease and/or hypoxemia. Group 4 is PH due to pulmonary artery obstruction, most commonly from venous thromboembolism (VTE). Group 5 is PH due to multifactorial mechanisms. The clinician can diagnose PH via a right heart catheterization (RHC) showing a mean pulmonary artery pressure (mPAP) of over 25mm Hg or a pulmonary vascular resistance (PVR) greater than 3 Woods units. A normal pulmonary artery wedge pressure of under 15 mmHg is required to exclude group 2 PH. Currently, there are several pulmonary vasodilator agents with approval for the medical management of PAH, including endothelin receptors antagonists (ERA), phosphodiesterase-5 (PDE-5) inhibitors, and prostanoids.[1][2]