Impact of Tricuspid Annuloplasty Device Shape and Size on Valve Mechanics - A Virtual Case Study

Abstract

Tricuspid valve disease significantly affects 1.6 million Americans. The gold-standard treatment for tricuspid disease is the implantation of annuloplasty devices. These ring-like devices come in various shapes and sizes. Choices for both shape and size are most often made by surgical intuition rather than scientific rationale. To understand the impact of shape and size on valve mechanics and to provide a rational basis for their selection, we used a subject-specific finite element model to conduct a virtual case study. That is, we implanted four different annuloplasty devices of six different sizes in our virtual patient. After each virtual surgery, we computed the coaptation area, leaflet end-systolic angles, leaflet stress, and chordal forces. We found that contoured devices are better at normalizing end-systolic angles, while the one flat device, the Edwards Classic, maximized coaptation area, and minimized leaflet stress and chordal forces. We further found that reducing device size led to increased coaptation area but also negatively impacted end-systolic angles, stress, and chordal forces. Our case study demonstrates the potential impact of device shape and size on measures of valve mechanics. Expanding our study to many more valves may, in the future, allow for universal recommendations.