Non-uniform mixing of hepatic venous flow and inferior vena cava flow in the Fontan conduit

Non-uniform mixing of hepatic venous flow and inferior vena cava flow in the Fontan conduit

Rijnberg, Friso M. (Leiden University Medical Center)
van der Woude, S.F.S. (Erasmus MC)
van Assen, Hans C. (Leiden University Medical Center)
Juffermans, J.F. (Leiden University Medical Center)
Hazekamp, Mark G. (Leiden University Medical Center)
Jongbloed, Monique R.M. (Leiden University Medical Center)
Kenjeres, S. (TU Delft ChemE/Transport Phenomena)
Lamb, Hildo J. (Leiden University Medical Center)
Westenberg, Jos J.M. (Leiden University Medical Center)

2021

Fontan patients require a balanced hepatic blood flow distribution (HFD) to prevent pulmonary arteriovenous malformations. Currently, HFD is quantified by tracking Fontan conduit flow, assuming hepatic venous (HV) flow to be uniformly distributed within the Fontan conduit. However, this assumption may be unvalid leading to inaccuracies in HFD quantification with potential clinical impact. The aim of this study was to (i) assess the mixing of HV flow and inferior vena caval (IVC) flow within the Fontan conduit and (ii) quantify HFD by directly tracking HV flow and quantitatively comparing results with the conventional approach. Patient-specific, time-resolved computational fluid dynamic models of 15 total cavopulmonary connections were generated, including the HV and subhepatic IVC. Mixing of HV and IVC flow, on a scale between 0 (no mixing) and 1 (perfect mixing), was assessed at the caudal and cranial Fontan conduit. HFD was quantified by tracking particles from the caudal (HFDcaudal conduit) and cranial (HFDcranial conduit) conduit and from the hepatic veins (HFDHV). HV flow was non-uniformly distributed at both the caudal (mean mixing 0.66 ± 0.13) and cranial (mean 0.79 ± 0.11) level within the Fontan conduit. On a cohort level, differences in HFD between methods were significant but small; HFDHV (51.0 ± 20.6%) versus HFDcaudal conduit (48.2 ± 21.9%, p = 0.033) or HFDcranial conduit (48.0 ± 21.9%, p = 0.044). However, individual absolute differences of 8.2-14.9% in HFD were observed in 4/15 patients. HV flow is non-uniformly distributed within the Fontan conduit. Substantial individual inaccuracies in HFD quantification were observed in a subset of patients with potential clinical impact.

computational fluid dynamics
flow
Fontan
hepatic flow distribution
hepatic venous
mixing

http://resolver.tudelft.nl/uuid:7243ddf7-1889-4147-8a1f-1d03d8c12281

https://doi.org/10.1098/rsif.2020.1027

1742-5689

Journal of the Royal Society Interface, 18 (177)

Institutional Repository

journal article

© 2021 Friso M. Rijnberg, S.F.S. van der Woude, Hans C. van Assen, J.F. Juffermans, Mark G. Hazekamp, Monique R.M. Jongbloed, S. Kenjeres, Hildo J. Lamb, Jos J.M. Westenberg, More Authors