[Contrast echocardiography in the diagnosis of severe hypoxemia associated with liver cirrhosis].

Severe hypoxemia is an uncommon feature of hepatic cirrhosis. Its major cause are intrapulmonary arteriovenous shunts, both due to direct arteriovenous communications and abnormally dilated pulmonary capillaries. In the present study, a case of cirrhosis associated with severe hypoxemia is reported. Contrast echocardiography showed pulmonary arteriovenous shunts, and low values of mixed venous blood (15% or less were obtained with the method of 100% oxygen breathing). These data suggest that the basic mechanism of hypoxemia, in this case, were capillary dilatations rather than true pulmonary arteriovenous anastomoses. The pathophysiological mechanisms of hypoxemia in cirrhosis are discussed, with emphasis on the present relevance of echocardiography for a full evaluation of these patients, particularly when liver transplantation is contemplated.