Aortic Valve: investigation by engineering tools Universit degli - PowerPoint PPT Presentation

Biomechanics Aortic Valve: investigation by engineering tools Università degli Studi di Pavia - Structural Mechanics Department 1

Aortic Valve AORTIC VALVE SPARING PROCEDURE Effects of Aortic root delation - Coaptazion area reduction - Valve incompetence 1) Excision of aortic root in 3) Whole re-implanted aortic 2) Anchoring of the prosthesis order to achieve an ad hoc valve, within prosthesis tube, tube, replacing ascending structure containing the presenting mercedes star like aorta, and excised aortic native valve shape valve The procedure requires high technical expertise Procedure Planning 2

Aortic Valve GENERATION OF GEOMETRIC MODEL Patient Medical images Finite element Geometric K1,..,Kn Output analysis model Boundary Image analysis conditions Approach 1: closed configuration 3 Approach 2: open configuration

Aortic Valve METHOD FOR THE MESH GENERATION Finally, by a circular replication � � � � Parametric model Mirroring operation � � 1/3 � � whole model of the aortic valve in reproduces 1/6 of of the aortic valve open configuration the aortic valve 4

Aortic Valve PARAMETERS OF THE MODEL (1/6 OF VALVE) Different views of the same element: Ht Ht � � Hr F F Rb Rb • base radius, Rb [13 mm] * • total height, Ht [16.8 mm] • maximum height of the aortic root, Hr [10.8 mm] • slope of the aortic root, � [6° ] • slope of the leaflet, � [7° ] • parameters of the “intermediate-line” function 5 * Parameter Values based on Labrosse et al . 2006

Aortic Valve NUMERICAL SIMULATIONS – “HEALTH” VALVE Patient Medical images Finite Geometric Output element model analysis Boundary Image analysis conditions Bottom view Side view 6

Aortic Valve NUMERICAL SIMULATIONS – PATHOLOGIC VALVE Pathologic aortic valve model is generated enlarging aortic root Bottom view Side view Side view Top view Bottom view Valve is not able to close completely 7