Aortic Aneurysms: OSR, EVAR, Stent-Grafts, Migration and Endoleak—Current State of the Art and Analysis

Numerical, simulations of blood flow effects under the presence of abdominal aortic aneurysm

“…The collaboration of clinicians and bioengineers has boosted the innovation of stent-graft designs with varying stent material, graft fabric, fixation, deployment precision, ease of use, delivery sheath size, and flexibility. 19 The material of the stent-graft is subject to the pulsatile arterial blood flow. Polyethylene terephthalate (PET; e.g., Dacron) and polytetrafluoroethylene (PTFE; e.g., Teflon) are high strength, resilient, and lightweight polymers, of which most aortic stent-grafts are typically constructed.…”

“…It represents one or more of the following processes: incomplete sealing of the proximal or distal landing sites (type I); continued blood flow into the sac by collateral and lumbar vessels (type II); an incomplete seal at junctions of overlapping graft components or ruptured graft fabric (type III); or leakage of blood through a porous graft membrane (type IV), Figure 7. 19 The incidence of endoleak is approximately 20% and may be further classified as immediate, early, or late. Without treatment, the aneurysm may continue to expand, thus carrying the risk of rupture, although most cases seal spontaneously with thrombosis.…”