Objective

The aim of our study was to evaluate the impact of aortic root replacement by graft on the elastic properties of the descending thoracic aorta using cardiac magnetic resonance imaging (MRI) and automatic post-processing.

Materials and methods

Nineteen patients were operated for an aortic root aneurysm. Cardiac MRI was performed before and after surgery to measure aortic compliance. Images were acquired on a 1.5 T MRI with a conventional aortic MRI protocol plus one additional kinetic sequence orientated perpendicularly to the aorta at the level of pulmonary trunk. The contours of the ascending and descending aortas were detected automatically for each phase with homemade software.

Results

Mean time between surgical procedure and earliest post-operative MRI was 18.2 ± 7.1 months. There was no significant difference between the pre- and earliest post-operative mean descending aorta areas and no significant modification in descending aortic compliance after aortic root replacement (1.43 ± 0.84 vs 1.37 ± 0.58 mm²/mmHg, p = 0.47). Pre- and post-operative systolic and diastolic blood pressure were similar. There was a significant decrease in ascending aortic compliance after surgery (2.52 ± 1.24 vs 0.91 ± 0.52 mm²/mmHg; p < 0.0001).

Discussion

The aortic root replacement by graft was not associated with changes in elastic properties of the descending aorta at short term.

Clinical registration number

NCT03817008.

中文翻译：

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心脏磁共振成像评价移植升主动脉置换对胸降主动脉弹性特性的影响。

客观的

我们研究的目的是使用心脏磁共振成像 (MRI) 和自动后处理评估移植主动脉根部置换对胸降主动脉弹性特性的影响。

材料和方法

19 名患者因主动脉根部动脉瘤接受了手术治疗。在手术前后进行心脏 MRI 以测量主动脉顺应性。图像是在 1.5 T MRI 上获得的，采用传统的主动脉 MRI 协议加上一个额外的动力学序列，在肺干水平垂直于主动脉。使用自制软件自动检测每个阶段的升主动脉和降主动脉轮廓。

结果

手术和最早的术后 MRI 之间的平均时间为 18.2 ± 7.1 个月。术前和术后最早的平均降主动脉面积之间没有显着差异，主动脉根部置换术后降主动脉顺应性也没有显着变化（1.43 ± 0.84 vs 1.37 ± 0.58 mm ² /mmHg，p  = 0.47）。术前和术后收缩压和舒张压相似。手术后升主动脉顺应性显着下降（2.52 ± 1.24 vs 0.91 ± 0.52 mm ² /mmHg；p  < 0.0001）。

讨论

移植物主动脉根部置换与短期内降主动脉弹性特性的变化无关。

临床注册号

NCT03817008。