[Liver diseases and pulmonary vascular disorders]

About 70% patients waiting for liver transplantation have a dyspnea. Two pulmonary vascular disorders can be associated with portal hypertension or chronic liver diseases: portopulmonary hypertension (PoPH) related to pulmonary small arteries remodeling and obstruction and hepatopulmonary syndrome (HPS) characterized by pulmonary capillaries dilatations and proliferations. PoPH is defined by the combination of pulmonary arterial hypertension (PAH) (mean pulmonary artery pressure [PAP]≥25mmHg, with normal pulmonary artery wedge pressure≤15mmHg and pulmonary vascular resistance [PVR]>3 Wood units [WU]) and portal hypertension. HPS is a triad of intrapulmonary vascular dilatations, hypoxemia (increased alveolar-arterial oxygen gradient) and liver disease or isolated portal hypertension. The pathophysiology of both syndromes is complex and poorly understood. PoPH and HPS have a negative impact on functional and vital prognosis in patients with portal hypertension. Liver transplantation is the established treatment standard in HPS. PoPH treatment is improved over the years with the use of specific PAH treatment despite the lack of randomized assay in this indication. Liver transplantation could be considered in PoPH leading to stabilization, improvement or recovery in selected patients (mean PAP<35mmHg without severe right ventricular dysfunction and PVR<4 WU).