FibroScan as a surveillance marker post-cavopulmonary anastomosis for single-ventricle physiology

Single-ventricle physiology encompasses a group of congenital cardiac malformations with only one functional ventricle. The Fontan procedure is the final palliation of this pathway and has its complications. One of these is Fontan-associated liver disease (FALD). It is known that all patients with Fontan will have FALD, due to the physiology of the Fontan circuit, and only the severity will vary. The pathophysiology of hepatic damage in FALD is unique and not easily detectable by routine non-invasive investigations. Therefore, this study is aimed to identify if FibroScan can be used as a surveillance marker to detect and assess the progression of FALD.

Patients who attended the Cardiothoracic and Vascular Surgery Outpatient Department (OPD) for follow-up post-cavopulmonary anastomosis (bidirectional Glenn and Fontan) were enrolled in this study. They underwent routine examinations and tests, and in addition a FibroScan was performed.

FibroScan showed that the liver stiffness measurement (LSM) was increased in all patients who had undergone Fontan and a couple of patients who had undergone bidirectional (BD) Glenn. The LSM was 12.29 (± 3.59) kPa in patients post-Fontan and 6.64 (± 4.24) kPa in patients post-BD Glenn. This raised LSM was not associated with a parallel rise in liver enzymes or other laboratory markers associated with liver function. This emphasizes the suitability of FibroScan as an early and non-invasive surveillance tool for monitoring the progression of hepatic venous congestion and FALD.

We have found that LSM via FibroScan can effectively be a surveillance or screening test for FALD. Serial FibroScans can be used to monitor the progress of liver disease. Raised LSM may also have a role in predicting the morbidity for completion of Fontan post-BD Glenn operation. Large-scale studies are needed to validate our findings.