Choi Perry S, Sharir Amit, Ono Yoshikazu, Shibata Masafumi, Kaiser Alexander D, Palagani Yellappa, Marsden Alison L, Ma Michael R
Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, Stanford University, Palo Alto, Calif.
Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Palo Alto, Calif.
JTCVS Open. 2024 Sep 17;22:395-404. doi: 10.1016/j.xjon.2024.09.008. eCollection 2024 Dec.
The study objective was to investigate the effect of free-edge length on valve performance in bicuspidization repair of congenitally diseased aortic valves.
In addition to a constructed unicuspid aortic valve disease model, 3 representative groups-free-edge length to aortic diameter ratio 1.2, 1.57, and 1.8-were replicated in explanted porcine aortic roots (n = 3) by adjusting native free-edge length with bovine pericardium. Each group was 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 used to compare outcomes across groups.
The diseased control group had a mean transvalvular gradient of 28.3 ± 5.5 mm Hg, regurgitation fraction of 29.6% ± 8.0%, and orifice area of 1.03 ± 0.15 cm. In ex vivo analysis, all repair groups had improved regurgitation and transvalvular gradient compared with the diseased control group ( < .001). Free-edge length to aortic diameter of 1.8 had the highest amount of regurgitation among the repair groups ( < .001) and 1.57 the least ( < .001). Free-edge length to aortic diameter of 1.57 also exhibited the lowest mean gradient ( < .001) and the largest orifice area ( < .001).
Free-edge length to aortic diameter ratio significantly impacts valve function in bicuspidization repair of congenitally diseased aortic valves. As the ratio departs from 1.57 in either direction, effective orifice area decreases and both transvalvular gradient and regurgitation fraction increase.
本研究旨在探讨在先天性病变主动脉瓣双叶化修复中，游离缘长度对瓣膜性能的影响。
除构建单叶主动脉瓣疾病模型外，通过用牛心包调整天然游离缘长度，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直径之比分别为1.2、1.57和1.8。每组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结果。
病变对照组的平均跨瓣压差为28.3±5.5 mmHg，反流分数为29.6%±8.0%，瓣口面积为1.03±0.15 cm²。在离体分析中，与病变对照组相比，所有修复组的反流和跨瓣压差均有所改善（P <.001）。修复组中，游离缘长度与主动脉直径之比为1.8时反流最多（P <.001），1.57时最少（P <.001）。游离缘长度与主动脉直径之比为1.57时，平均压差也最低（P <.001），瓣口面积最大（P <.001）。
在先天性病变主动脉瓣双叶化修复中，游离缘长度与主动脉直径之比显著影响瓣膜功能。当该比值向任何一个方向偏离1.57时，有效瓣口面积减小，跨瓣压差和反流分数均增加。
