A computational tool to support pre-operative planning of stentless aortic valve prosthesis

In some cases of aortic valve leaflet disease, the implant of a stentless biological prosthesis represents an excellent option for aortic valve replacement (AVR). In particular, if compared to more classical surgical approaches, it provides a more physiological hemodynamic performance and a minor trombogeneticity avoiding the use of anticoagulants. The clinical outcomes of AVR are strongly dependent on an appropriate choice of both prosthesis size and replacement technique, which are, at present, strictly related to surgeon's experience and skill. Therefore, also this treatment, like most reconstructive procedures in cardiac surgery, remains "more art than science" [1]. Nowadays computational methodologies represent a useful tool both to investigate the aortic valve behavior, in physiologic and pathologic conditions and to reproduce virtual post-operative scenarios. The present study aims at supporting the AVR procedure planning through a patient-specific Finite Element Analysis (FEA) of stentless valve implantation. Firstly, we perform FEA to simulate the prosthesis placement inside the patient-specific aortic root; then, we reproduce, again by means of FEA, the diastolic closure of the valve to evaluate both the coaptation and the stress/strain state. The simulation results prove that both the valve size and the anatomical asymmetry of the Valsalva sinuses affect the prosthesis placement procedure.