P145. Optimal Commissural Height-to-Annular Diameter Ratio in Valve-Sparing Root Replacement: Ex-Vivo Evaluation with a Novel Ringed Graft
Presented During: Adult Cardiac Poster Session II
Stanford University School of Medicine
Campbell, CA
United States - Contact Me
Chris Huynh, BS, is a Life Science Research Professional in the Stanford Advanced Therapeutics and Surgical Biomechanics Research Laboratory where he conducts research on the biomechanics of mitral and aortic valve surgery. He received his undergraduate degree in Chemical and Biomedical Engineering from Carnegie Mellon University and is currently applying to medical school.
Monday, May 4, 2026: 9:00 AM - 4:00 PM
McCormick Place Lakeside Center
Room: Exhibit Hall, Poster Area
Description
Objective: In valve-sparing aortic root replacement (VSARR), the restoration of physiologic hemodynamics necessitates accurate reconstruction of the aortic root to its native geometry. Specifically, the commissural height relative to the annular diameter is critical to establishing proper aortic leaflet coaptation. This ratio, however, has not been well defined and is typically guided by surgeon experience. To address this, we investigated the optimal ratio using a novel 3D-printed coronet-shaped ring sewn into a woven polyester graft to standardize commissural positioning relative to annular diameter.
Methods: Five porcine aortic roots (median annular diameter 25 mm, ranging 23-27 mm) were reimplanted into our novel ringed grafts with height-to-diameter ratios of 0.85, 1.00, and 1.15 (Figure A, B) in a randomized order. Hemodynamic testing was performed on an ex vivo left heart simulator under physiologic conditions. The primary variable of interest was aortic regurgitation fraction (ARF). Secondary measurements included mean transaortic gradient, effective orifice area (EOA), and transvalvular energy loss throughout the cardiac cycle. Leaflet kinematics (opening/closing velocity and relative force) were also assessed.
Results: Across all measured variables, the 1.00 ratio consistently outperformed the 0.85 and 1.15 ratios: ARF was lowest with 1.00 (1.52±0.88%) compared with 0.85 (4.39±4.45%) and 1.15 (2.95±2.42%) (P<0.001, Figure C); mean transaortic gradient was most favorable at 1.00 (21.1±8.1 mmHg vs. 29.3±11.4 and 27.7±12.6 mmHg, P<0.001); EOA was largest with 1.00 (1.74±0.70 cm² vs. 1.50±0.43 and 1.29±0.18 cm², P<0.001); transvalvular energy loss was minimized at 1.00 (127.2±84.8 mJ vs. 192.9±91.7 and 281.5±29.9 mJ, P<0.001). Leaflet velocities and forces were comparable among groups (P>0.05).
Conclusions: A commissural height-to-annular diameter ratio of 1.00 best minimizes ARF, optimizes pressure gradients and EOA, and reduces energy loss without impairing leaflet dynamics. These findings establish 1.00 as a geometric target for VSARR and support the development of standardized ringed grafts engineered to restore physiologic hemodynamics.
Figure. (A) The 3D-printed novel rings with commissural height-to-annular diameters of 0.85, 1.00, and 1.15. (B) The porcine aortic root is reimplanted into a 1.00 ringed graft using mattress sutures and subsequently mounted on our ex vivo evaluation platform. (C) ARF among 0.85, 1.00, and 1.15 ringed grafts.
Authors
Chris Huynh (1), Seung Hyun Lee (1), Masafumi Shibata (1), Matthew Park (1), Stefan Elde (1), Michael Paulsen (2), Joon Bum Kim (3), Y. Joseph Woo (1)
Institutions
(1) Stanford University, Stanford, CA, (2) Cottage Health, Santa Barbara, CA, (3) Asan Medical Center, Seoul, Korea
Methods: Five porcine aortic roots (median annular diameter 25 mm, ranging 23-27 mm) were reimplanted into our novel ringed grafts with height-to-diameter ratios of 0.85, 1.00, and 1.15 (Figure A, B) in a randomized order. Hemodynamic testing was performed on an ex vivo left heart simulator under physiologic conditions. The primary variable of interest was aortic regurgitation fraction (ARF). Secondary measurements included mean transaortic gradient, effective orifice area (EOA), and transvalvular energy loss throughout the cardiac cycle. Leaflet kinematics (opening/closing velocity and relative force) were also assessed.
Results: Across all measured variables, the 1.00 ratio consistently outperformed the 0.85 and 1.15 ratios: ARF was lowest with 1.00 (1.52±0.88%) compared with 0.85 (4.39±4.45%) and 1.15 (2.95±2.42%) (P<0.001, Figure C); mean transaortic gradient was most favorable at 1.00 (21.1±8.1 mmHg vs. 29.3±11.4 and 27.7±12.6 mmHg, P<0.001); EOA was largest with 1.00 (1.74±0.70 cm² vs. 1.50±0.43 and 1.29±0.18 cm², P<0.001); transvalvular energy loss was minimized at 1.00 (127.2±84.8 mJ vs. 192.9±91.7 and 281.5±29.9 mJ, P<0.001). Leaflet velocities and forces were comparable among groups (P>0.05).
Conclusions: A commissural height-to-annular diameter ratio of 1.00 best minimizes ARF, optimizes pressure gradients and EOA, and reduces energy loss without impairing leaflet dynamics. These findings establish 1.00 as a geometric target for VSARR and support the development of standardized ringed grafts engineered to restore physiologic hemodynamics.
Figure. (A) The 3D-printed novel rings with commissural height-to-annular diameters of 0.85, 1.00, and 1.15. (B) The porcine aortic root is reimplanted into a 1.00 ringed graft using mattress sutures and subsequently mounted on our ex vivo evaluation platform. (C) ARF among 0.85, 1.00, and 1.15 ringed grafts.
Authors
Chris Huynh (1), Seung Hyun Lee (1), Masafumi Shibata (1), Matthew Park (1), Stefan Elde (1), Michael Paulsen (2), Joon Bum Kim (3), Y. Joseph Woo (1)
Institutions
(1) Stanford University, Stanford, CA, (2) Cottage Health, Santa Barbara, CA, (3) Asan Medical Center, Seoul, Korea
Presentation Duration
There is no formal presentation for posters. Your poster will be on display on your assigned day from 9:00AM - 4:00PM
View Submission
ADULT CARDIAC
Aortic Valve