Idiopathic pulmonary arterial hypertension.

Despite improved understanding of the pathobiology of pulmonary arterial hypertension (PAH), it remains a severe and progressive disease, usually culminating in right heart failure, significant morbidity and early mortality. Over the last decade, some major advances have led to substantial improvements in the management of PAH. Much of this progress was pioneered by work in animal models. Although none of the current animal models of pulmonary hypertension (PH) completely recapitulate the human disease, they do provide insight into the cellular pathways contributing to its development and progression. There is hope that future work in model organisms will help to define its underlying cause(s), identify risk factors and lead to better treatment of the currently irreversible damage that results in the lungs of afflicted patients. However, the difficulty in defining the etiology of idiopathic PAH (IPAH, previously known as primary pulmonary hypertension) makes this subset of the disease particularly difficult to model. Although there are some valuable existing models that are relevant for IPAH research, the area would value from the development of new models that more closely mimic the clinical pathophysiology of IPAH.