Cardiac and vascular changes in cirrhosis： Pathogenic mechanisms

Cardiovascular abnormalities accompany both portal hy-pertension and cirrhosis.These consist of hyperdynamiccirculation,defined as reduced mean arterial pressureand systemic vascular resistance,and increased cardiacoutput.Despite the baseline increased cardiac output,ventricular inotropic and chronotropic responses tostimuli are blunted,a condition known as cirrhotic car-diomyopathy.Both conditions may play an initiating oraggravating pathogenic role in many of the complicationsof liver failure or portal hypertension including ascites,variceal bleeding,hepatorenal syndrome and increasedpostoperative mortality after major surgery or livertransplantation.This review briefly examines the majormechanisms that may underlie these cardiovascular ab-normalities,concentrating on nitric oxide,endogenouscannabinoids,central neural activation and adrenergicreceptor changes.Future work should address the com-plex interrelationships between these systems.

Cardiac and vascular changes in cirrhosis: pathogenic mechanisms

Cardiovascular abnormalities accompany both portal hy- pertension and cirrhosis.These consist of hyperdynamic circulation,defined as reduced mean arterial pressure and systemic vascular resistance,and increased cardiac output.Despite the baseline increased cardiac output, ventricular inotropic and chronotropic responses to stimuli are blunted,a condition known as cirrhotic car- diomyopathy.Both conditions may play an initiating or aggravating pathogenic role in many of the complications of liver failure or portal hypertension including ascites, variceal bleeding,hepatorenal syndrome and increased postoperative mortality after major surgery or liver transplantation.This review briefly examines the major mechanisms that may underlie these cardiovascular ab- normalities,concentrating on nitric oxide,endogenous cannabinoids,central neural activation and adrenergic receptor changes.Future work should address the com- plex interrelationships between these systems.