Abstract 19568: Hemodynamic Assessment of an Augmented Aorta: a Rapid Prototyping Technique
Introduction: Interest in high fidelity aortic flow phantoms remains significant even with advancements in computational fluid dynamic methods. We present a process for creating a patient-specific, compliant aortic arch and valve (AoV) along with our corresponding validation efforts.
Methods: A rendered aortic volume was created by threshold-based segmentation in Mimics (Materialise, Leuven, Belgium) and edited in 3-matic to create a 3D printed mold (Object Connex 5000, Stratasys, Edina, Minnesota) into which a polyurethane based resin (Smooth-on, Easton, Pennsylvania) was cast. The AoV was created in a similar manner and ultimately seated in the distal end of an inlet port designed to induce laminar flow. The arch, with fixed inlet, was then constrained to the correct anatomical conformation by a custom rapid prototyped chamber. An MRI-compatible pump programmed to match the patient’s flow profile managed flow of a 40% glycerin-aqueous solution. Both through-plane and 4D phase contrast velocity mapping MRI sequences were acquired and compared to the patient data with time-elapse flow streamlines calculated by GTFlow version 2.0.1 (GyroTools, Zurich Switzerland).
Results: The phantom remained robust and compliant throughout the dynamic loading occurring under pulsatile flow. Registration revealed good alignment of the phantom lumen to the segmented patient aorta. 4D flow analysis showed an unusual left-handed helical flow pattern in both the in vivo patient data and derived phantom flows. Flow measurements in the ascending and descending aorta of the model agreed within 5% of the actual patient measured flow.
Conclusions: We have demonstrated a viable method to create patient-specific flow phantoms, which closely mimic the physiological system for which they are modeled. Further studies are needed to optimize the valve anatomy and wall compliance.
Author Disclosures: K.A. Gralewski: None. K.K. Whitehead: None. Y. Dori: None.
- © 2014 by American Heart Association, Inc.