P135. Improved Hemodynamic Performance with a 3-Dimensional Reinforced Ringed-Graft for Valve-Sparing Aortic Root Replacement in Bicuspid Aortic Valve
Stanford University
Sunnyvale, CA
United States - Contact Me
I am a board-certified cardiothoracic surgeon in Japan and a visiting instructor in the Department of Cardiothoracic Surgery at Stanford University School of Medicine.
I am a board-certified cardiothoracic surgeon in Japan and am serving as a visiting instructor in the Department of Cardiothoracic Surgery at Stanford University School of Medicine. My professional expertise centers around cardiovascular surgery, encompassing procedures such as aortic valve replacement (AVR), transcatheter aortic valve replacement (TAVR), coronary artery bypass graft (CABG) surgery, thoracic and endovascular aortic repair (EVAR and TEVAR), and surgical intervention for end-stage heart failure.
My academic background includes Ph.D. studies in cardiovascular surgery, with a specific focus on Platelet-Rich Plasma (PRP) and its role in promoting angiogenesis and enhancing tissue regeneration. I conducted research applying PRP to a rabbit ischemic sternum model, employing a combination of gelatin hydrogel. The findings demonstrated that the controlled release of PRP from locally applied gelatin hydrogel significantly improved sternal healing.
Currently, my research endeavors involve tissue imaging utilizing the Light Sheet Microscope (LSM), where I analyze microstructures and angiogenesis. My career aspiration is to achieve leadership in the field of academic cardiovascular surgery. In my current role, I am dedicated to expanding my academic contributions and furthering my impact in the realm of cardiovascular surgical research.
Description
Methods: A semi-rigid 3D-printed photopolymer frame (A) replicating the valvulo-aortic junction was integrated into a 28-mm woven polyester graft (B). Five porcine hearts were studied in a validated ex-vivo left heart simulator after creation of a BAV model by fusing two cusps to form a pseudo-raphe. For the novel procedure, multiple mattress sutures were placed around the trimmed aortic root (C), passed through the device, and tied to seat it onto the root, requiring only a single-layer suture line (D). Each root underwent both the novel VSARR and David reimplantation in randomized order to equalize baseline conditions. Hemodynamic performance - including aortic regurgitation (AR), effective orifice area (EOA), transvalvar pressure gradient, and leaflet kinematics - was analyzed by left-heart simulator and with high-speed leaflet tracking.
Results: The novel VSARR demonstrated significantly lower AR fraction (7.8 ± 2.9% vs 18.5 ± 7.3%, p = 0.03, E), larger EOA (1.47 ± 0.19 cm² vs 1.19 ± 0.21 cm², p = 0.03, F) and a trend toward lower transvalvar pressure gradient (5.1 ± 1.4 mmHg vs 8.6 ± 2.3 mmHg, p = 0.16, G) compared with conventional reimplantation. Leaflet opening, closing, and acceleration dynamics were comparable between groups.
Conclusions: In an ex-vivo BAV model, VSARR using the novel 3D reinforced ringed-graft achieved superior hemodynamic outcomes with lower AR fraction and larger EOA compared with the conventional reimplantation technique. By enabling seating of the graft with a simplified single-layer suture line, this device may streamline VSARR, enhance reproducibility beyond only the most experienced surgeons. Further in vivo and clinical studies are warranted.
Authors
Masafumi Shibata (1), Perry Choi (2), Amit Sharir (3), Chris Huynh (4), Riya Nilkant (5), Matthew Park (6), Sarah Chen (7), Michael Ma (8), Y. Joseph Woo (3), Joon Bum Kim (9)
Institutions
(1) Stanford University, Sunnyvale, CA, (2) Stanford University, Palo Alto, CA, (3) Stanford University, Stanford, CA, (4) Stanford University School of Medicine, Campbell, CA, (5) Stanford University School of Medicine, CA, (6) Stanford University School of Medicine, Palo Alto, CA, (7) University of Michigan, Ann Arbor, MI, (8) Stanford University School of Medicine, Stanford, CA, (9) Asan Medical Center, Seoul, NA