Patient-specific image-based computer simulation for the prediction of valve morphology and calcium displacement after TAVI with the Medtronic CoreValve and the Edwards SAPIEN valve

Aims: Our aim was to validate patient-specific software integrating baseline anatomy and biomechanical properties of both the aortic root and valve for the prediction of valve morphology and aortic leaflet calcium displacement after TAVI. Methods and results: Finite element computer modelling was performed in 39 patients treated with a Medtronic CoreValve System (MCS; n=33) or an Edwards SAPIEN XT (ESV; n=6). Quantitative axial frame morphology at inflow (MCS, ESV) and nadir, coaptation and commissures (MCS) was compared between multislice computed tomography (MSCT) post TAVI and a computer model as well as displacement of the aortic leaflet calcifications, quantified by the distance between the coronary ostium and the closest calcium nodule. Bland-Altman analysis revealed a strong correlation between the observed (MSCT) and predicted frame dimensions, although small differences were detected for, e.g., Dmin at the inflow (mean +/- SD MSCT vs. model: 21.6 +/- 2.4 mm vs. 22.0 +/- 2.4 mm; difference +/- SD: -0.4 +/- 1.3 mm, p<0.05) and Dmax (25.6 +/- 2.7 mm vs. 26.2 +/- 2.7 mm; difference +/- SD: -0.6 +/- 1.0 mm, p<0.01). The observed and predicted calcium displacements were highly correlated for the left and right coronary ostia (R-2=0.67 and R-2=0.71, respectively p<0.001). Conclusions: Dedicated software allows accurate prediction of frame morphology and calcium displacement after valve implantation, which may help to improve outcome.