[Pulmonary hypertension in liver diseases].

Portopulmonary hypertension (PoPH) is defined by the combination of portal hypertension and precapillary pulmonary hypertension (mPAP ≥ 25 mmHg, PCWP < 15 mmHg and PVR > 3 Wood units). PoPH is characterised by pathobiological mechanisms that are similar to other forms of pulmonary arterial hypertension. Prevalence of PoPH is estimated at 0.5-5% among patients with portal hypertension with or without cirrhosis. Treatment strategies most commonly employed for PoPH patients are based on recommendations for idiopathic PAH management. Indeed, the choice of specific PAH treatment must take account the severity of the underlying liver disease. Prognosis of PoPH patients is dependent on both the severity of PAH and of the underlying liver disease. PoPH may be a contraindication for orthotopic liver transplantation (OLT) if mean pulmonary arterial pressure is > 35 mmHg associated with severe right ventricular dysfunction or high level of pulmonary vascular resistance (> 3-4 Wood units). Bridge therapy with specific PAH therapies should be considered in those patients in an attempt to improve pulmonary hemodynamic and thereby allow OLT with acceptable risk. Recent data suggest that stabilize, improve or cure PoPH seems to be possible by combining specific PAH therapies and liver transplantation in selected patients. Clinical and experimental evidences suggest that IFN therapy may be a possible risk factor for PAH.