Device-related thrombus in transcatheter aortic valve implantation: a fluid-structure interaction study

Abstract

Transcatheter aortic valve implantation (TAVI) is a minimally invasive heart procedure that has emerged as a safe and effective treatment for patients with severe symptomatic aortic stenosis (AS). This is a common heart pathology consisting of the aortic valve’s narrowing leading to an obstruction of the left ventricular outflow tract. Recently, TAVI has been approved for all AS risk groups given the low complication rates reported. However, there are many post-TAVI complications such as device-related thrombus (DRT). This is a multi-factorial problem that lacks comprehensive understanding and effective treatment. In this context, numerical simulations have emerged as alternative tools to assess and predict thrombus formation. Therefore, the objective of this study was to present a computational workflow for modelling patient-specific TAVI under a fluid-structure interaction (FSI) approach to study the risk of developing DRT post-TAVI. Clinical data of one patient who underwent TAVI was provided by Hospital de la Santa Creu i Sant Pau (Barcelona, Spain). The proposed workflow consisted of the following steps: (1) acquiring patient-specific data; (2) developing the model including patient-specific geometry and TAVI prosthesis; (3) setting up the FSI simulation; (4) validating the results obtained; and (5) analyzing haemodynamic thrombus indices to assess the risk of DRT after TAVI. Sensitivity analyses were conducted to evaluate parameter influence on the FSI simulation setup. This study lead to relevant conclusions to set the basis for future work regarding the study of patient-specific TAVI modelling under an FSI approach to address DRT.