Pathophysiology Behind Cardiopulmonary Complications of Cirrhosis and Portal Hypertension

Development of portal hypertension is a serious complication of cirrhosis. In addition to liver-related complications, extrahepatic functional disturbances are often seen in multiple organs including the cardiovascular and respiratory systems. Progressive fibrosis of the liver and subsequent metabolic impairment lead to a systemic and splanchnic arteriolar vasodilatation. This affects both the haemodynamic and functional homeostasis of many organs and largely determines the course of the disease. With the progression of the disease, the circulation becomes hyperdynamic with cardiac and respiratory consequences leading to organ dysfunction and reduced survival. Changed cardiac function known as cirrhotic cardiomyopathy may be involved in further aggravation of other complications such as renal failure precipitating the hepatorenal syndrome. The cirrhotic cardiomyopathy encompasses systolic, diastolic, as well as electromechanical dysfunctions of the heart. Besides, the abnormal haemodynamic and humoral balance are involved in development of the hepatopulmonary syndrome with pulmonary vascular dilatations resulting in arterial hypoxaemia in the presence of liver disease. Porto-pulmonary hypertension is a condition of increased pulmonary artery pressure in the presence of portal hypertension, which is a condition associated with a high mortality. In decompensated cirrhotic patients pleural effusions as hepatic hydrothorax often cause respiratory discomfort. The present book chapter highlights contemporary aspects of pathophysiology and related diagnostic and therapeutic aspects of these serious cardio-respiratory complications of cirrhosis and portal hypertension.