Brain Natriuretic Peptide in Liver Cirrhosis and Fatty Liver: Correlation with Cardiac Performance

OBJECTIVE: The aims of the present study were to assess the serum BNP level in patients with post hepatitis C liver cirrhosis and patients with fatty liver and to determine the correlation between BNP and the severity of liver disease and cardiac performance. METHODS: The study was conducted on 140 subjects subdivided into 3 groups: group 1 included 60 patients having post hepatitis C virus (HCV) liver cirrhosis; group 2 included 60 patients with nonalcoholic fatty liver disease (NAFLD); and group 3 included 20 healthy volunteers serving as a control group. All patients and volunteers were subjected to full physical examinations, laboratory evaluation of hemoglobin percent, liver and renal function tests, serum electrolytes, cholesterol, triglyceride, HBs antigen, HCV antibody and serum BNP levels, ECG, abdominal ultrasonography, and echocardiography. RESULTS: There was a significant increase in the BNP level in cirrhotic patients compared to the other two groups (p = 0.000), and it was correlated with the severity of liver disease assigned as Child’s classification (p = 0.000). Also, there was a significant increase in the BNP level in cirrhotic patients with decompensation components compared to those without decompensation components (p = 0.000), history of hepatic encephalopathy (p = 0.000), history of variceal bleeding (p = 0.000), history of spontaneous bacterial peritonitis (p = 0.000), presence of ascites (p = 0.000) and portal vein diameter > 11 mm in abdominal ultrasound (p = 0.000), and prolonged QTc interval in ECG (p = 0.011). There was a significant increase in serum BNP in patients with cirrhosis with the following echocardiographic findings: IVST > 11 mm, PWT > 11 mm, LA diameter > 40 mm, EF% < 54%, and E/A ratio < 1 compared to those without these echocardiographic findings (p = 0.000). CONCLUSION: BNP level increases in post hepatitis C cirrhotic patients and tends to decrease in fatty liver disease patients, and it is correlated with both the severity of liver disease and the morpho-functional cardiac changes. Given the ever-increasing prevalence of liver cirrhosis and fatty liver disease worldwide, it is important to understand the benefits and limitations of BNP as a heart failure biomarker in hepatic patients, where the relationship between BNP level and myocardial function is complex and is altered by the liver disease.