Choi Perry S, Sharir Amit, Ono Yoshikazu, Shibata Masafumi, Kaiser Alexander D, Zhu Yuanjia, Marsden Alison L, Woo Y Joseph, Ma Michael R, Kim Joon Bum
Department of Cardiothoracic Surgery, Stanford University, Palo Alto, Calif.
Department of Pediatrics, Division of Pediatric Cardiology, Stanford University, Palo Alto, Calif.
JTCVS Tech. 2024 Apr 16;25:1-7. doi: 10.1016/j.xjtc.2024.03.025. eCollection 2024 Jun.
To investigate the effect of graft sizing on valve performance in valve-sparing aortic root replacement for bicuspid aortic valve.
In addition to a diseased control model, 3 representative groups-free-edge length to aortic/graft diameter (FELAD) ratio <1.3, 1.5 to 1.64, and >1.7-were replicated in explanted porcine aortic roots (n = 3) using straight grafts sized respective to the native free-edge length. They were run on a validated ex vivo univentricular system under physiological parameters for 20 cycles. All groups were tested within the same aortic root to minimize inter-root differences. Outcomes included transvalvular gradient, regurgitation fraction, and orifice area. Linear mixed effects model and pairwise comparisons were employed to compare outcomes across groups.
The diseased control had mean transvalvular gradient 10.9 ± 6.30 mm Hg, regurgitation fraction 32.5 ± 4.91%, and orifice area 1.52 ± 0.12 cm. In ex vivo analysis, all repair groups had improved regurgitation compared with control ( < .001). FELAD <1.3 had the greatest amount of regurgitation among the repair groups ( < .001) and 1.5-1.64 the least ( < .001). FELAD <1.3 and >1.7 exhibited greater mean gradient compared with both control and 1.5 to 1.64 ( < .001). Among the repair groups, 1.5 to 1.64 had the largest orifice area, and >1.7 the smallest ( < .001).
For a symmetric bicuspid aortic valve, performance after valve-sparing aortic root replacement shows a bimodal distribution across graft size. As the FELAD ratio departs from 1.5 to 1.64 in either direction, significant increases in transvalvular gradient are observed. FELAD <1.3 may also result in suboptimal improvement of baseline regurgitation.
研究在保留瓣膜的主动脉根部置换术治疗二叶式主动脉瓣时，移植物尺寸对瓣膜性能的影响。
除了一个病变对照模型外，使用根据天然游离缘长度定制尺寸的直形移植物，在离体猪主动脉根部（n = 3）中复制3个代表性组——游离缘长度与主动脉/移植物直径（FELAD）之比<1.3、1.5至1.64和>1.7。它们在经过验证的离体单心室系统上，在生理参数下运行20个周期。所有组均在同一个主动脉根部内进行测试，以尽量减少根部间差异。结果包括跨瓣压差、反流分数和瓣口面积。采用线性混合效应模型和两两比较来比较各组的结果。
病变对照组的平均跨瓣压差为10.9±6.30 mmHg，反流分数为32.5±4.91%，瓣口面积为1.52±0.12 cm²。在离体分析中，与对照组相比，所有修复组的反流均有所改善（P <.001）。在修复组中，FELAD <1.3的反流程度最大（P <.001），1.5 - 1.64的反流程度最小（P <.001）。与对照组和1.5至1.64组相比，FELAD <1.3和>1.7组的平均压差更大（P <.001）。在修复组中，1.5至1.64组的瓣口面积最大，>1.7组的瓣口面积最小（P <.001）。
对于对称性二叶式主动脉瓣，保留瓣膜的主动脉根部置换术后的性能在移植物尺寸上呈现双峰分布。当FELAD比值在任一方向偏离1.5至1.64时，观察到跨瓣压差显著增加。FELAD <1.3也可能导致基线反流的改善不理想。
