title: The influence of bicuspid aortic valves on the dynamic pressure distribution in the ascending aorta: a porcine ex vivo model.
abstract: OBJECTIVE
  The aim of the study was to simulate the effect of different bicuspid aortic valve configurations on the dynamic pressure distribution in the ascending aorta.
  
  
  METHODS
  Aortic specimens were harvested from adult domestic pigs. In Group 1, bicuspidalization was created by a running suture between the left and the right coronary leaflets (n = 6) and in Group 2 by a running suture between the left and the non-coronary leaflets (n = 6). Eleven tricuspid specimens served as controls. Two intraluminal pressure catheters were positioned at the concavity and the convexity of the ascending aorta. The specimens were connected to a mock circulation (heart rate: 60 bpm, target pressure: 95 mmHg). A comparison of the different conditions was also done in a numerical simulation.
  
  
  RESULTS
  At a distal mean aortic pressure of 94 ± 10 mmHg, a mean flow rate of 5.2 ± 0.3 l/min was achieved. The difference of maximal dynamic pressure values (which occurred in systole) between locations at the convexity and the concavity was 7.8 ± 2.9 mmHg for the bicuspid and 1.0 ± 0.9 mmHg for the tricuspid specimens (P < 0.001). The numerical simulation revealed an even higher pressure difference between convexity and concavity for bicuspid formation.
  
  
  CONCLUSIONS
  In this hydrodynamic mock circulation model, we were able to demonstrate that bicuspid aortic valves are associated with significant pressure differences in different locations within the ascending aorta compared with tricuspid aortic valves. These altered pressure distributions and flow patterns may further add to the understanding of aneurismal development in patients with bicuspid aortic valves and might serve to anticipate adverse aortic events due to a better knowledge of the underlying mechanisms.
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria Department of Cardiac Surgery and Transplantation, The Cardinal Stefan Wyszynski Institute of Cardiology, Warsaw, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Juraszek
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Dziodzio
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Stoiber
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria.
authors.forename: Daniel
authors.initials: D
authors.lastname: Fechtig
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria.
authors.forename: Verena
authors.initials: V
authors.lastname: Gschlad
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Aigner
authors.affiliation: Department of Cardiovascular Surgery, University Hospital Berne, Berne, Switzerland martin.czerny@insel.ch.
authors.forename: Martin
authors.initials: M
authors.lastname: Czerny
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria Department of Cardiac Surgery, Medical University, Vienna, Austria.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Schima
mesh_terms: D000818:Animals; D001011:Aorta / Q000502:physiology*; D001021:Aortic Valve / Q000002:abnormalities* / Q000503:physiopathology; D062186:Arterial Pressure / Q000502:physiology; D000082882:Bicuspid Aortic Valve Disease; D003198:Computer Simulation; D006349:Heart Valve Diseases / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology*; D008955:Models, Cardiovascular; D013552:Swine
keywords: Aneurysm; Bicuspid aortic valve; Circulation model; Dynamic pressure; Haemodynamics