Pulmonary arterial hypertension (PAH) is a rare and severe condition characterised by vascular proliferation and remodelling of the small pulmonary arteries, resulting in a progressive increase in pulmonary vascular resistance leading to right ventricular failure and premature death [1]. Two decades ago, patients with idiopathic PAH had a dismal median survival rate from diagnosis of <3 yrs, despite available supportive treatment [2]. Since then, meaningful randomised controlled trials have been conducted thanks to a worldwide collaboration of expert centres operating with a similar standard of medical care [3, 4]. Eight drugs belonging to three pharmacological classes (endothelin receptor antagonists, phosphodiesterase type-5 inhibitors and prostanoids) administered by four different routes (oral, inhaled, subcutaneous and intravenous) have been approved [5]. None of these therapies is curative, but they contributed to allow PAH to evolve from a uniformly fatal condition to a chronic disease in some cases [6].
Because of the rarity of PAH and the need for specific management of …