Andrzej Juraszek1, Tomasz Dziodzio2, Martin Stoiber2, Daniel Fechtig3, Verena Gschlad2, Philipp Aigner2, Martin Czerny4, Heinrich Schima5. 1. 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. 2. Center for Medical Physics and Biomedical Engineering, Vienna, Austria Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria. 3. Center for Medical Physics and Biomedical Engineering, Vienna, Austria. 4. Department of Cardiovascular Surgery, University Hospital Berne, Berne, Switzerland martin.czerny@insel.ch. 5. 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.
Abstract
OBJECTIVES: 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.
OBJECTIVES: 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: Hector W L de Beaufort; Margherita Coda; Michele Conti; Theodorus M J van Bakel; Foeke J H Nauta; Ettore Lanzarone; Frans L Moll; Joost A van Herwaarden; Ferdinando Auricchio; Santi Trimarchi Journal: PLoS One Date: 2017-10-05 Impact factor: 3.240