title: Total Cavopulmonary Connection is Superior to Atriopulmonary Connection Fontan in Preventing Thrombus Formation: Computer Simulation of Flow-Related Blood Coagulation.
abstract: The classical Fontan route, namely the atriopulmonary connection (APC), continues to be associated with a risk of thrombus formation in the atrium. A conversion to a total cavopulmonary connection (TCPC) from the APC can ameliorate hemodynamics for the failed Fontan; however, the impact of these surgical operations on thrombus formation remains elusive. This study elucidates the underlying mechanism of thrombus formation in the Fontan route by using a two-dimensional computer hemodynamic simulation based on a simple blood coagulation rule. Hemodynamics in the Fontan route was simulated with Navier-Stokes equations. The blood coagulation and the hemodynamics were combined using a particle method. Three models were created: APC with a square atrium, APC with a round atrium, and TCPC. To examine the effects of the venous blood flow velocity, the velocity at rest and during exercise (0.5 and 1.0 W/kg) was measured. The total area of the thrombi increased over time. The APC square model showed the highest incidence for thrombus formation, followed by the APC round, whereas no thrombus was formed in the TCPC model. Slower blood flow at rest was associated with a higher incidence of thrombus formation. The TCPC was superior to the classical APC in terms of preventing thrombus formation, due to significant blood flow stagnation in the atrium of the APC. Thus, local hemodynamic behavior associated with the complex channel geometry plays a major role in thrombus formation in the Fontan route.
authors.affiliation: Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia.
authors.forename: Koichi
authors.initials: K
authors.lastname: Sughimoto
authors.affiliation: Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, Chiba, Japan.|Hitachi Construction Machinery, Tokyo, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Okauchi
authors.affiliation: Murdoch Childrens Research Institute, Melbourne, Australia.
authors.forename: Diana
authors.initials: D
authors.lastname: Zannino
authors.affiliation: Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia.|Murdoch Childrens Research Institute, Melbourne, Australia.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Brizard
authors.affiliation: School of Naval Architecture, Ocean and Civil Engineering (NAOCE), Shanghai Jiao Tong University, Shanghai, China.|Shanghai Jiao Tong University and Chiba University International Cooperative Research Centre (SJTU-CU ICRC), Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Fuyou
authors.initials: F
authors.lastname: Liang
authors.affiliation: Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, Chiba, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Sugawara
authors.affiliation: Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, Chiba, Japan.|Shanghai Jiao Tong University and Chiba University International Cooperative Research Centre (SJTU-CU ICRC), Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Mechanical Engineering, Graduate School of Engineering, Chiba University, Chiba, Japan. tsubota@faculty.chiba-u.jp.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D001777:Blood Coagulation; D001783:Blood Flow Velocity / Q000502:physiology*; D003198:Computer Simulation / Q000706:statistics & numerical data*; D018729:Fontan Procedure / Q000009:adverse effects*; D006439:Hemodynamics; D006801:Humans; D008955:Models, Cardiovascular; D011651:Pulmonary Artery / Q000601:surgery; D012039:Regional Blood Flow; D013927:Thrombosis / Q000517:prevention & control*; D014682:Vena Cava, Inferior / Q000601:surgery
keywords: Computer simulation; Congenital heart disease; Fontan; Hemodynamics; Thrombus