Pharmacotherapeutic management of pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a disabling chronic disorder of the pulmonary vasculature, which is characterized by increased pulmonary artery pressure as a result of increased pulmonary vascular resistance. The pathology of PAH is characterized by pulmonary vascular vasoconstriction, smooth muscle cell proliferation, and thrombosis. These changes are a result of an imbalance between vasodilators (prostacyclin, nitric oxide, vasoactive intestinal peptide) and vasoconstrictors (thromboxane A2, endothelin, serotonin), growth inhibitors and mitogenic factors, and antithrombotic and prothrombotic factors. Recent advances in treatment are directed at restoring the balance between these systems. Endothelin receptor antagonists (bosentan, ambrisentan, sitaxsentan), phosphodiesterase type 5 inhibitors (sildenafil, tadalafil), and prostacylin (epoprostenol, iloprost, treprostinil, beraprost) represent the different classes of medications that are currently used in monotherapy and in combination to treat PAH. The purpose of this drug highlight is to provide the reader with an update of the pharmacotherapeutic treatment of PAH.