Abstract 20259: Rapid Prototyping of the Aortic Root in Severe Aortic Stenosis for Pre-TAVR Planning
Introduction: Rapid prototyping 3D printing technique has emerged as a promising tool for device testing and treatment planning in cardiovascular surgery and intervention. We tested the feasibility of printing patient-specific and material-specific aortic valves in 3D, and evaluated the post-TAVR annular strain distribution on the printed model in-vitro.
Methods: We used 2 pre-TAVR CT scans, one had severe aortic stenosis (AS) with mild calcification, and the other had severe AS with severe calcification which extended into the LVOT; and one CTA scan that had a normal aortic valve (AV). The perimeter-derived annular diameters were all within the range of 21-22 mm. We reconstructed the patient-specific root models at peak AV opening from CT, and used an Object350 Connex polyjet printer (Stratasys, Rehovot Israel) to print them in 3D (Fig. A1-3) using specific printing materials that resembled the mechanical properties of the arterial wall, the valvular leaflets, and the calcified lesions (materials used: TangoPlus FLX930, FLX9940-DM, and VeroClear RGD810, respectively). Arrows in Fig. A showed the calcifications. Strain sensors were attached to the 3D printed models at the locations of the left, right, and non annular hinges (Fig. B), where strain values were digitally captured by a computer (Fig. D). We implanted a prosthetic valve (CoreValve, size: 26) into the patient-specific 3D printed models (Fig. C), and monitored the change of the strain values at the annular hinges, as the CoreValve expanded. Stabilized strain values were recorded.
Results: The 3D printed valves exhibited comparable material properties with human tissues. The strain values (Fig. E) in the severely calcified AV were much higher than in the normal and mildly calcified AV (0.12±0.03%, 0.00±0.00%, 0.00±0.00%, respectively).
Conclusions: Rapid prototyping and in-vitro strain assessment of the patient-specific aortic root using 3D printing may improve pre-TAVR planning.
Author Disclosures: Z. Qian: None. C. Wu: None. Y. Chang: None. C. Zhang: Research Grant; Modest; Department of Veterans Affairs. B. Wang: Research Grant; Modest; Department of Veterans Affairs. V. Rajagopal: None. S. Liu: None. X. Zhou: None. J. Kauten: None. R. Ionasec: None. H. Houle: None. R. Martin: None. M. Vannan: None.
- © 2014 by American Heart Association, Inc.