Pulmonary arterial hypertension (PAH) is a term used to classify a variety of conditions that
share in common an injury to the pulmonary vasculature that produces elevations in
pulmonary arterial pressure. However, it is the integrity of right ventricular function, rather
than the degree of vascular injury, that is the major determinant of symptoms and survival in
PAH. The article will review the normal structure and function of the right ventricle and
summarize the impact of PAH and its treatments on right ventricular function.