Liver stiffness modifications shortly after total cavopulmonary connection

Area of Science:

• Pediatric Cardiology
• Hepatology
• Medical Imaging

Background:

• Hepatic damage, primarily fibrosis, is a known complication in Fontan circulation patients, though its mechanisms are not fully understood.
• Transient hepatic elastography (Fibro-Scan) is a non-invasive method for assessing liver stiffness and fibrosis.
• Increased inferior vena cava pressure post-total cavopulmonary connection may affect Fibro-Scan accuracy.

Purpose of the Study:

• To investigate the impact of increased venous pressure on Fibro-Scan results in patients undergoing total cavopulmonary connection.
• To quantify perioperative changes in liver stiffness using Fibro-Scan.
• To correlate liver stiffness changes with perioperative clinical and biochemical data.

Main Methods:

• A prospective observational study involving 9 pediatric patients undergoing extracardiac total cavopulmonary connection.
• Fibro-Scan assessments of hepatic stiffness were performed immediately before and 4 months after surgery.
• Results were analyzed in conjunction with perioperative data, including pulmonary pressures, conduit characteristics, hepatic enzymes, and coagulation parameters.

Main Results:

• Hepatic stiffness significantly increased from a mean of 6.2 ± 1.5 kPa preoperatively to 11.2 ± 4 kPa at 4 months post-surgery (P < 0.01).
• Perioperative changes in alanine aminotransferase (ALT) and aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio showed significant correlations with liver stiffness increase.
• Pearson Correlation Indexes for ALT and AST/ALT ratio with liver stiffness raise were 0.8 (P < 0.01) and -0.7 (P < 0.01), respectively.

Conclusions:

• Liver stiffness rises rapidly after total cavopulmonary connection, likely due to hepatic congestion rather than true fibrosis in the early stages.
• Fibro-Scan is effective for monitoring liver stiffness changes over time in this population.
• Conventional interpretation of Fibro-Scan results in Fontan patients may be misleading due to elevated venous pressure, necessitating careful evaluation of changes over time.