Portal hypertension and cirrhosis can result in complex changes in the pulmonary vascular bed, the most important among them being the hepatopulmonary syndrome and portopulmonary hypertension. When pulmonary hypertension accompanies cirrhosis and portal hypertension, it is seldom diagnosed. Its prevalence is estimated to range from 1% to 2% in patients with portal hypertension or cirrhosis, regardless of gender, and the condition is predominantly seen in patients in their 40s. Etiologic factors have not been sufficiently well defined to explain the increase in pulmonary artery pressure and pulmonary vascular resistance. Most patients are asymptomatic until developing dyspnea on exertion, which generally occurs when the mean pulmonary artery pressure exceeds 40 mmHg. Concomitant hepatic disease with progressive hypoxemia or right ventricular failure increase mortality rates. Further studies are needed in order to determine the benefits of using oral, inhaled or intravenous vasodilators, as well as to evaluate the outcomes of liver transplant, which may be the sole definitive therapeutic option.
Oxygen free radicals; Antioxidant substances; Oxidative stress; Lung diseases
