Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, IL, USA; Université Paris Centre, PARCC INSERM, 75015 Paris, France.
Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston 60208, IL, USA.
Diagn Interv Imaging. 2022 Sep;103(9):418-426. doi: 10.1016/j.diii.2022.04.003. Epub 2022 May 4.
The purpose of this study was to investigate the relationships between hemodynamic parameters and longitudinal changes in aortic dimensions on four-dimensional (4D) flow magnetic resonance imaging (MRI) in patients with bicuspid aortic valve (BAV) and repaired coarctation.
The study retrospectively included patients with BAV and childhood coarctation repair who had at least two cardiothoracic MRI examinations including 4D flow MRI at baseline and follow-up. Analysis included the calculation of aortic peak velocities, wall shear stress (WSS), pulse wave velocity (PWV), aortic dimensions and annual growth rates. Differences between examinations were assessed using paired t-test or Wilcoxon signed rank test. Relationships between growth rate and 4D flow metrics were assessed using Pearson or Spearman correlation tests.
The cohort included 15 patients (mean age 35 ± 8 [SD] years, 9 men) with a median follow-up time of 3.98 years (Q1: 2.10; Q3: 4.96). There were no significant differences in aortic mean WSS, peak velocities, and PWV between baseline and follow-up values. Greater baseline peak velocities at the site of the coarctation were strongly associated with aortic narrowing (follow-up vs. baseline diameter) at coarctation zone (r = -0.64; P = 0.010) and moderately in descending aorta (r = -0.53; P = 0.042). In addition, increased baseline WSS in the aortic arch was strongly related with narrowing of the coarctation zone at follow-up (r = -0.64, P = 0.011).
Measures of aortic hemodynamics and aortic WSS are stable over time in patients with BAV with coarctation repair. Increased peak velocity was associated with a progressive narrowing at the site of the coarctation repair.
本研究旨在探讨二维（4D）流磁共振成像（MRI）中血流动力学参数与升主动脉尺寸纵向变化之间的关系，研究对象为患有二叶式主动脉瓣（BAV）和修复性主动脉缩窄的患者。
本研究回顾性纳入了至少两次心胸 MRI 检查（包括基线和随访时的 4D 流 MRI）的 BAV 和儿童期主动脉缩窄修复患者。分析包括计算主动脉峰值速度、壁面切应力（WSS）、脉搏波速度（PWV）、主动脉尺寸和年增长率。使用配对 t 检验或 Wilcoxon 符号秩检验评估检查之间的差异。使用 Pearson 或 Spearman 相关检验评估生长率与 4D 流指标之间的关系。
该队列纳入了 15 名患者（平均年龄 35 ± 8 [SD] 岁，9 名男性），中位随访时间为 3.98 年（Q1：2.10；Q3：4.96）。在基线和随访时，主动脉平均 WSS、峰值速度和 PWV 之间无显著差异。在缩窄部位的基线峰值速度越大，与缩窄区域（随访时与基线直径相比）的主动脉狭窄（r=-0.64；P=0.010）呈强相关，与降主动脉的相关性中等（r=-0.53；P=0.042）。此外，主动脉弓的基线 WSS 增加与随访时缩窄区域的狭窄密切相关（r=-0.64，P=0.011）。
在 BAV 伴主动脉缩窄修复患者中，主动脉血流动力学和 WSS 随时间推移而稳定。峰值速度增加与缩窄修复部位的进行性狭窄有关。
