ABSTRACT
Tetrahydrobiopterin (BH4) is an essential cofactor in NO synthesis by endothelial nitric oxide synthase (eNOS) enzymes. It has been previously suggested that reduced intrahepatic BH4 results in a decrease in intrahepatic NO and contributes to increased hepatic vascular resistance and portal pressure in animal models of cirrhosis. The main aim of the present study was to evaluate the relationship between BH4 and portal hypertension (PHT). One hundred ninety-three consecutive patients with chronic liver disease were included in the study. Liver biopsy, measurement of BH4 and hepatic venous pressure gradient (HVPG) were performed. Hepatic fibrosis was classified using the Laennec fibrosis scoring system. BH4 levels were determined in homogenized liver tissues of patients using a high performance liquid chromatography (HPLC) system. Statistical analysis was performed to evaluate the relationship between BH4 and HVPG, grade of hepatic fibrosis, clinical stage of cirrhosis, Child-Pugh class. A positive relationship between HVPG and hepatic fibrosis grade, clinical stage of cirrhosis and Child-Pugh class was observed. However, the BH4 level showed no significant correlation with HVPG or clinical features of cirrhosis. BH4 concentration in liver tissue has little relation to the severity of portal hypertension in patients with chronic liver disease.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Biopterins/analogs & derivatives , Chromatography, High Pressure Liquid , Chronic Disease , Elasticity Imaging Techniques , Hepatic Veins/physiology , Hypertension, Portal/complications , Liver/pathology , Liver Cirrhosis/diagnostic imaging , Liver Diseases/complications , Nitric Oxide/metabolism , Portal Pressure , Regression Analysis , Severity of Illness IndexABSTRACT
Portal hypertension is a severe consequence of chronic liver diseases and is responsible for the main clinical complications of liver cirrhosis. Hepatic venous pressure gradient (HVPG) measurement is the best available method to evaluate the presence and severity of portal hypertension. Clinically significant portal hypertension is defined as an increase in HVPG to >10 mmHg. In this condition, the complications of portal hypertension might begin to appear. HVPG measurement is increasingly used in the clinical fields, and the HVPG is a robust surrogate marker in many clinical applications such as diagnosis, risk stratification, identification of patients with hepatocellular carcinoma who are candidates for liver resection, monitoring of the efficacy of medical treatment, and assessment of progression of portal hypertension. Patients who had a reduction in HVPG of > or =20% or to < or =12 mmHg in response to drug therapy are defined as responders. Responders have a markedly decreased risk of bleeding/rebleeding, ascites, and spontaneous bacterial peritonitis, which results in improved survival. This review provides clinical use of HVPG measurement in the field of liver disease.
Subject(s)
Humans , Chronic Disease , Hemodynamics , Hemorrhage/etiology , Hepatic Veins/physiology , Hypertension, Portal/complications , Liver Cirrhosis/diagnosis , Liver Diseases/complications , Portal PressureABSTRACT
Exponemos nuestra experiencia en una pequeña serie de casos con la toma de presiones en las venas suprahepáticas en posición de atascamiento. Señalamos su técnica y recalcamos su importancia en el diagnóstico diferencial de las hipertensiones portales suprahepáticas, infrahepáticas e intrahepáticas(AU)