Anomalies pulmonaires au cours des maladies hépatiques

Respiratory manifestations are common in cirrhotic patients, with dyspnea as the most frequent. In most cases, these manifestations are related to non specific disorders including bacterial infections or lung base atelectasia in case of large ascites. Less frequently, cirrhotic patients develop specific respiratory disorders: hepatic hydrothorax, hepatopulmonary syndrome and portopulmonary hypertension. Hepatic hydrothorax results from the passage of ascites into the pleural cavity. It can be observed even in the absence of large ascites. Hepatic hydrothorax may be responsible for dyspnea and hypoxemia. Despite diuretics, pleural effusion can restore rapidly after thoracentesis. Iterative thoracentesis should be avoided because of a high incidence of complications. Liver transplantation represents the best therapeutic option. TIPS placement or chemical pleurodesis are acceptable alternative therapies when liver transplantation is not possible, but their efficacy is inconstant. Hepatopulmonary syndrome is characterized by an intrapulmonary shunt resulting from massive microvascular dilatation. It occurs in about 5 % of cirrhotic patients and the main manifestation is hypoxemia. Hepatopulmonary syndrome significantly reduces life expectancy in cirrhotic patients. Oxygen therapy can improve manifestations but liver transplantation remains the only proven therapy based upon the total resolution of hypoxemia in almost all patients. Portopulmonary hypertension results from pulmonary arterial vasoconstriction and concentric intimal fibrosis leading to precapillary pulmonary hypertension. It occurs to 1 to 2% of cirrhotic patients and remains latent until mean pulmonary artery pressure exceeds 40 mmHg. Hypoxemia is absent or moderate. In the absence of any specific treatment, the prognosis is poor, and death is due in most cases to cardiac arrest or to end-stage cardiac insufficiency. Echocardiography is helpful for detecting portopulmonary hypertension but definitive diagnosis should be based on the results of right heart catheterization. Prostacyclin analogues may sometimes decrease durably pulmonary artery pressure. Liver transplantation can be performed when pulmonary artery pressure is only mildly elevated but post transplantation resolution seems inconstant. Severe portopulmonary hypertension represents a contraindication to transplantation because of a high rate of perioperative mortality.