Hardikar Ashutosh, Harle Robin, Marwick Thomas H
Menzies Institute for Medical Research, University of Tasmania, Australia.
Department of Cardiothoracic Surgery, Royal Hobart Hospital, Hobart, Australia.
Aorta (Stamford). 2020 Oct;8(5):132-140. doi: 10.1055/s-0040-1715609. Epub 2020 Dec 23.
This study aimed at risk-stratifying aortic dilatation using aortic wall thickness (AWT) and comparing methods of AWT assessment.
Demographic, epidemiological, and perioperative data on 72 consecutive aortic surgeries (age = 62 years[standard deviation (SD) = 12] years) performed by a single surgeon were collected from hospital database. Aortic thickness was measured on computed tomography scans, as well as intraoperatively in four quadrants, at the level of aortic sinuses, as well as midascending aorta, using calipers. Aortic wall stress was calculated using standard mathematical formulae.
The ascending aorta was 48.2 (SD = 8) mm and the mean thickness at ascending aorta level was 1.9 (SD = 0.3) mm. There was congruence between imaging and intraoperative measurements of thickness, as well as between the radiologist and surgeon. Preoperatively, 16 patients had multiple imaging studies showing an average rate of growth of 1.2 mm per year without significant difference in thickness. The wider the aorta, the thinner was the lateral or convex wall. Aortic stenosis ( = 0.01), lateral to medial wall thickness ratio ( = 0.04), and history of hypertension ( = 0.00), all had protective effect on aortic root stress. The ascending aortic stress was directly affected by age ( = 0.03) and inversely related to lateral to medial wall thickness ratio ( = 0.03).
Aortic thickness can be measured preoperatively and easily confirmed intraoperatively. Risk stratification based on both aortic thickness and diameter (stress calculations) would better predict acute aortic events in dilated aortas and define aortic resection criteria more objectively.
本研究旨在利用主动脉壁厚度（AWT）对主动脉扩张进行风险分层，并比较AWT评估方法。
从医院数据库中收集了由一名外科医生连续进行的72例主动脉手术的人口统计学、流行病学和围手术期数据（年龄=62岁[标准差（SD）=12岁]）。在计算机断层扫描上测量主动脉厚度，并在术中使用卡尺在主动脉窦水平以及升主动脉中部的四个象限中测量。使用标准数学公式计算主动脉壁应力。
升主动脉为48.2（SD=8）mm，升主动脉水平的平均厚度为1.9（SD=0.3）mm。厚度的影像学测量与术中测量之间以及放射科医生与外科医生之间存在一致性。术前，16例患者进行了多项影像学研究，显示平均每年生长速度为1.2mm，厚度无显著差异。主动脉越宽，外侧或凸面壁越薄。主动脉狭窄（=0.01）、外侧与内侧壁厚度比（=0.04）和高血压病史（=0.00）均对主动脉根部应力有保护作用。升主动脉应力直接受年龄影响（=0.03），与外侧与内侧壁厚度比呈负相关（=0.03）。
主动脉厚度可在术前测量，并在术中轻松确认。基于主动脉厚度和直径（应力计算）的风险分层将能更好地预测扩张主动脉的急性主动脉事件，并更客观地定义主动脉切除标准。
