Immersogeometric fluid-structure interaction modeling and simulation of transcatheter aortic valve replacement

Comput Methods Appl Mech Eng. 2019 Dec 1:357:112556. doi: 10.1016/j.cma.2019.07.025. Epub 2019 Aug 14.

Abstract

The transcatheter aortic valve replacement (TAVR) has emerged as a minimally invasive alternative to surgical treatments of valvular heart disease. TAVR offers many advantages, however, the safe anchoring of the transcatheter heart valve (THV) in the patients anatomy is key to a successful procedure. In this paper, we develop and apply a novel immersogeometric fluid-structure interaction (FSI) framework for the modeling and simulation of the TAVR procedure to study the anchoring ability of the THV. To account for physiological realism, methods are proposed to model and couple the main components of the system, including the arterial wall, blood flow, valve leaflets, skirt, and frame. The THV is first crimped and deployed into an idealized ascending aorta. During the FSI simulation, the radial outward force and friction force between the aortic wall and the THV frame are examined over the entire cardiac cycle. The ratio between these two forces is computed and compared with the experimentally estimated coefficient of friction to study the likelihood of valve migration.

Keywords: Bioprosthetic heart valves; Fluid–structure interaction; Immersogeometric analysis; Isogeometric beams and shells; TAVR; Transcatheter aortic valve replacement.