Neurohormonal modulation in pulmonary arterial hypertension

Pulmonary hypertension is a fatal condition of elevated pulmonary pressures, complicated by right heart failure. Pulmonary hypertension appears in various forms; one of those is pulmonary arterial hypertension (PAH) and is particularly characterized by progressive remodelling and obstruction of the smaller pulmonary vessels. Neurohormonal imbalance in these patients is associated with worse prognosis and survival. In this back-to-basics review on neurohormonal modulation in PAH, we provide an overview of the pharmacological and non-pharmacological strategies that have been tested preclinically and clinically. The benefit of neurohormonal modulation strategies in PAH patients has been limited by lack of insight in how the neurohormonal system is changed throughout the disease and difficulties in translation from animal models to human trials. We propose that longitudinal and individual assessments of neurohormonal status are required to improve timing and specificity of neurohormonal modulation strategies. Ongoing developments in imaging techniques such as positron emission tomography (PET) may become helpful to determine neurohormonal status in PAH patients in different disease stages and optimize individual treatment responses.