Novel therapeutic perspectives in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) refers to a disease spectrum of the small pulmonary arteries leading to a progressive increase in pulmonary vascular resistance, right ventricular failure and, ultimately, death 1. It is usually accepted that a vasoconstrictive factor is involved in PAH 2. However, pure vasodilators, such as calcium channel blockers, have so far provided little or no beneficial effects on survival in the vast majority of patients, presumably because the pulmonary arteriopathy characteristic of PAH includes fibrotic and proliferative changes that predominate over vasoconstriction 3. Interestingly, novel therapeutic agents, such as prostacyclin and endothelin-receptor antagonists, have a better clinical efficacy than pure vasodilators in PAH, presumably because they have both vasodilator and antiproliferative properties 4–6. Prostaglandin I2 (prostacyclin, epoprostenol) has been the most widely studied drug in PAH 5. Epoprostenol has a short half-life in the blood (3 min) and is inactivated at low pH 9. Therefore, epoprostenol can only be administered by continuous …