[Treatment algorithm for pulmonary arterial hypertension]

During the last decade, we have witnessed substantial improvements in the therapeutic options for pulmonary arterial hypertension (PAH), including true innovations targeting some of the mechanisms involved in the pathogenesis of this devastating disease. Intravenous epoprostenol was the first drug to improve symptoms and survival of patients with PAH. Novel prostanoids including subcutaneous treprostinil and inhaled iloprost also have beneficial effects in many patients, although their long-term efficacy is less well known. Among the newer treatments for PAH, endothelin receptor antagonists and phosphodiesterase type 5 inhibitors have reshaped clinical practice. The endothelin receptor antagonist bosentan has been approved in many parts of the world and most current guidelines recommend this drug as first-line treatment for PAH. Novel endothelin receptor antagonists such as sitaxsentan and ambrisentan are currently being investigated. The phosphodiesterase type 5 inhibitor sildenafil is also being intensively studied in patients with pulmonary hypertension, and most of the available data look promising, although approval for PAH is still pending. Other phosphodiesterase type 5 inhibitors have not yet undergone extensive study in PAH. However, PAH is a complex disorder and targeting a single pathway cannot be expected to be uniformly successful. Thus, combining substances with different modes of action is expected to improve symptoms, hemodynamics and survival in PAH patients, although combination therapy has yet to undergo the scrutiny of large randomized clinical trials.Based on the available data, several guidelines for the diagnostic and therapeutic approach to PAH have been published recently. These guidelines have incorporated treatment algorithms, which, fortunately, are virtually identical. The present review article summarizes the current guidelines to the management of patients with PAH.