Clinical implications of the hyperdynamic syndrome in cirrhosis.

The hyperdynamic syndrome is a late consequence of portal hypertension in cirrhosis. The principal hemodynamic manifestations of the hyperdynamic syndrome are high cardiac output, and increased heart rate and total blood volume, accompanied by reduced total systemic vascular resistance. Pathophysiology involves a complex of humoral and neural mechanisms that can determine hemodynamic changes, and lead to hyperdynamic circulation. In this review we focus our attention on the manifestations of the hyperdynamic syndrome. Some of these are well described and directly related to portal hypertension (varices, ascites, hepatic encephalopathy, and hepatorenal syndrome), while others, such as hepatopulmonary syndrome, portopulmonary hypertension, and cirrhotic cardiomyopathy, are less known as clinical manifestations related to cirrhosis and, therefore, merit further investigation.