The influence of coronary ostia positioning on leaflet fluttering in biological heart valve prostheses investigated through a fluid–structure computational model

Since the coronary ostia positioning affects local hemodynamics, it may also influence the leaflet oscillation features. It is essential to understand the parameters that influence leaflet fluttering, as this phenomenon intensifies the structural deterioration of biological heart valves. Therefore, this study aims to evaluate, through computational modeling, the effect of coronary ostia positioning on leaflet fluttering. A computational domain was developed consisting of leaflets, straight tubes at the inlet and outlet, the Valsalva sinuses, and coronary arteries. Six cases were examined: coronary arteries distant from the left ventricle and Newtonian blood; coronary arteries in the middle of the Valsalva sinuses and Newtonian blood; coronary arteries close to the left ventricle and Newtonian blood; without coronary arteries and Newtonian blood; coronary arteries distant from the left ventricle and non-Newtonian blood; and one case with fixed leaflets. The results indicated that oscillations were initiated and sustained due to the pressure field acting on leaflets, with dominant frequencies predominantly around 32.6 Hz. Moreover, the dynamic recirculation within the Valsalva sinuses caused by leaflet fluttering also influenced the flow entering the coronary arteries. The coronary ostia positioning did not have a significant impact on oscillations, but it did change the position of recirculation within the Valsalva sinuses. This study contributes to improving the understanding of variables influencing leaflet oscillations and may support the development of control strategies.