Continuous prazosin administration in cirrhotic patients: effects on portal hemodynamics and on liver and renal function.
ABSTRACT Hepatic vascular resistance is influenced by alpha-adrenergic tone. The aim of this study was to investigate the effects of continuous blockade of alpha-adrenoceptors with prazosin on hemodynamics, liver function, and renal function and whether the association of propranolol or furosemide enhances the portal pressure lowering effect of prazosin.
Cirrhotic patients with portal hypertension were studied at baseline and after a 3-month course of prazosin (n = 18) or placebo (n = 10).
No changes were observed in the placebo group. Prazosin decreased the hepatic venous pressure gradient (HVPG) while increasing hepatic blood flow. Liver function improved as shown by an increase in hepatic and intrinsic hepatic clearances of indocyanine green and galactose elimination capacity. A significant reduction in mean arterial pressure and systemic vascular resistance was associated with increases in plasma renin activity and aldosterone concentration and a decrease in glomerular filtration rate. The plasma volume increased significantly, and 6 patients developed edema. The association of propranolol (n = 8) but not furosemide (n = 7) to prazosin increased the reduction in HVPG and attenuated the increase in plasma renin activity.
In cirrhotic patients, continuous prazosin administration reduces portal pressure and improves liver perfusion and function but favors sodium and water retention. The association of propranolol enhances the decrease in portal pressure, suggesting a potential benefit from this combined therapy.
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ABSTRACT: Portal hypertension, a major hallmark of cirrhosis, is defined as a portal pressure gradient exceeding 5 mm Hg. In portal hypertension, porto-systemic collaterals decompress the portal circulation and give rise to varices. Successful management of portal hypertension and its complications requires knowledge of the underlying pathophysiology, the pertinent anatomy, and the natural history of the collateral circulation, particularly the gastroesophageal varices.Medical Clinics of North America 06/2008; 92(3):551-74, viii. · 2.47 Impact Factor
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ABSTRACT: Cirrhotic cardiomyopathy is a recently identified pathological condition defined as "a chronic cardiac dysfunction in patients with cirrhosis characterized by blunted contractile responsiveness to stress and/or altered diastolic relaxation with electrophysiological abnormalities, in the absence of known cardiac disease". Overall there seems to be a link between the progression of liver function impairment, the development of portal hypertension and the degree of hyperdynamic circulation, the hallmark of the deranged cardiovascular function in advanced liver diseases. Although mechanical factors contribute to much of the increased resistance within the liver in portal hypertension, there is clearly a vasculogenic component to the development, perpetuation and progression of this syndrome as well. The vascular component of portal hypertension includes an increase in splanchnic blood flow, as well as an increase in intrahepatic vascular resistance. Dysregulation of the nitric oxide system appears to play a key role in both these processes with a paradoxical reduction of intrahepatic availability despite increased disposal in the splanchnic and other vascular districts with adverse effects on cardiac function and structure. Nevertheless, other putative mediators of cardiac damage in cirrhosis have been proposed and their role in the pathogenesis of cirrhotic cardiomyopathy investigated. This review involves a discussion of data achieved on pathogenesis and clinical features of cirrhotic cardiomyopathy but mainly focuses on considerations on potential therapeutic targets, in the light of the evidence that this mainly subclinical condition merges to clinical relevance when challenged with those therapeutic interventions and procedures currently employed to treat the major complications of cirrhosis that might produce a negative impact on the cardiovascular system.Cardiovascular & Haematological Disorders - Drug Targets(Formerly Current Drug Targets - Cardiovascular & Hematological Disorders) 04/2007; 7(1):21-6.
Article: Ascites and hepatorenal syndrome in cirrhosis: pathophysiological basis of therapy and current management.Journal of Hepatology 02/2003; 38 Suppl 1:S69-89. · 9.26 Impact Factor