Department of Surgery, Aswan Heart Centre, Cairo, Egypt; National Heart and Lung Institute, Imperial College London, London, United Kingdom; Harefield Heart Science Centre, Harefield, Middlesex, United Kingdom.
Biomedical Engineering and Innovation Laboratory, Aswan Heart Centre, Cairo, Egypt; National Heart and Lung Institute, Imperial College London, London, United Kingdom.
J Thorac Cardiovasc Surg. 2018 Sep;156(3):951-962.e2. doi: 10.1016/j.jtcvs.2018.03.157. Epub 2018 Apr 13.
Valve-conserving operations for aneurysms of the ascending aorta and root offer many advantages, and their use is steadily increasing. Optimizing the results of these operations depends on providing the best conditions for normal function and durability of the new root.
Multimodality imaging including 2-dimensional echocardiography, multislice computed tomography, and cardiovascular magnetic resonance combined with image processing and computational fluid dynamics were used to define geometry, dynamism and aortic root function, before and after the remodeling operation. This was compared with 4 age-matched controls.
The size and shape of the ascending aorta, aortic root, and its component parts showed considerable changes postoperatively, with preservation of dynamism. The postoperative size of the aortic annulus was reduced without the use of external bands or foreign material. Importantly, the elliptical shape of the annulus was maintained and changed during the cardiac cycle (Δ ellipticity index was 15% and 28% in patients 1 and 2, respectively). The "cyclic" area of the annulus changed in size (Δarea: 11.3% in patient 1 and 13.1% in patient 2). Functional analysis showed preserved reservoir function of the aortic root, and computational fluid dynamics demonstrated normalized pattern of flow in the ascending aorta, sinuses of Valsalva, and distal aorta.
The remodeling operation results in near-normal geometry of the aortic root while maintaining dynamism of the aortic root and its components. This could have very important functional implications; the influence of these effects on both early- and long-term outcomes needs to be studied further.
保留瓣膜的升主动脉和根部动脉瘤手术具有许多优势,其应用也在稳步增加。优化这些手术的结果取决于为新根部的正常功能和耐久性提供最佳条件。
采用多模态成像技术(包括二维超声心动图、多层 CT 和心血管磁共振),结合图像处理和计算流体动力学,在重塑手术前后定义几何形状、动力学和主动脉根部功能,并与 4 名年龄匹配的对照组进行比较。
升主动脉、主动脉根部及其各组成部分的大小和形状在手术后发生了显著变化,但仍保持了动力学特征。术后主动脉瓣环的大小缩小,但未使用外部带或异物。重要的是,瓣环的椭圆形形状得到维持,并在心动周期中发生变化(患者 1 和 2 的椭圆指数分别变化了 15%和 28%)。瓣环的“循环”面积发生了变化(患者 1 和 2 的变化面积分别为 11.3%和 13.1%)。功能分析显示主动脉根部保留了储器功能,计算流体动力学显示升主动脉、瓦尔萨尔瓦窦和远端主动脉的血流模式正常化。
重塑手术使主动脉根部的几何形状接近正常,同时保持了主动脉根部及其各组成部分的动力学特征。这可能具有非常重要的功能意义;这些影响对早期和长期结果的影响需要进一步研究。