Department of Vascular Surgery, Rigshospitalet, University of Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. Electronic address: http://twitter.com/@Rigshospitalet.
Department of Vascular Surgery, Rigshospitalet, University of Copenhagen, Denmark.
Eur J Vasc Endovasc Surg. 2017 Oct;54(4):439-445. doi: 10.1016/j.ejvs.2017.06.016. Epub 2017 Jul 29.
Rupture risk in abdominal aortic aneurysms (AAAs) is assessed using AAA diameter; yet 10% of ruptures occur in a small aneurysm. This underlines the inadequacy of diameter as a standalone parameter. In this prospective follow-up study, ultrasound determined aneurysm diameter was compared with aneurysm volume determined by three dimensional ultrasound (3D-US) in a group of 179 AAAs.
This was a prospective cohort study with repeated diameter and volume measurements by 3D-US.
In total, 179 patients with small infrarenal AAAs (diameter 30-55 mm) were enrolled consecutively. At enrolment and at 12 month follow-up, maximum diameter, using dual plane technique, and three dimensional volume were measured. Based on a previous accuracy study, significant change in diameter and volume were defined as an increase exceeding the known range of variability (ROV) of each US technique; ±3.7 mm and ±8.8 mL, respectively. Post-hoc Kaplan-Meier analysis was performed to estimate time to conversion to treatment after the conclusion of the follow-up period between two groups.
In total, 125 patients (70%) had an unchanged diameter during follow-up. In this group, 50 patients (40%) had an increasing aortic volume. Forty-five (83%) of the 54 patients with an increasing aortic diameter showed a corresponding volume increase. During a median follow-up of 367 days (364-380 days), a mean increase in diameter of 2.7 mm (±2.6 mm) and a mean increase in volume of 11.6 mL (±9.9 mL) were recorded. In post-hoc analysis, it was found that more AAAs with a stable diameter and a growing volume than AAAs with a stable diameter and volume were undergoing aortic repair during follow-up, based on the maximum diameter.
In this cohort of small AAAs, 40% of patients with a stable diameter had an increasing volume at 12 month follow-up. From this perspective, 3D-US could have a future supplemental role in AAA surveillance programmes.
腹主动脉瘤（AAA）的破裂风险通过 AAA 直径来评估；然而，10%的破裂发生在小动脉瘤中。这突显出直径作为单一参数的不足。在这项前瞻性随访研究中，我们比较了 179 个 AAA 中通过超声确定的动脉瘤直径和通过三维超声（3D-US）确定的动脉瘤体积。
这是一项前瞻性队列研究，通过 3D-US 重复测量直径和体积。
总共连续纳入 179 例小肾下 AAA（直径 30-55mm）患者。在入组时和 12 个月随访时，使用双平面技术测量最大直径和三维体积。基于之前的准确性研究，将直径和体积的显著变化定义为增加超过每个 US 技术的已知变异性（ROV）范围；分别为±3.7mm 和±8.8mL。在两组随访结束后，进行事后 Kaplan-Meier 分析，以估计从随访期结束到治疗转换的时间。
在整个随访过程中，125 例患者（70%）的直径没有变化。在这一组中，50 例患者（40%）的主动脉体积增加。在 54 例主动脉直径增加的患者中，有 45 例（83%）有相应的体积增加。在中位随访 367 天（364-380 天）期间，直径平均增加 2.7mm（±2.6mm），体积平均增加 11.6mL（±9.9mL）。在事后分析中发现，与直径稳定且体积稳定的 AAA 相比，在随访期间，更多的 AAA 直径稳定但体积增大，需要进行主动脉修复。
在这个小 AAA 队列中，12 个月随访时 40%的直径稳定的患者体积增加。从这个角度来看，3D-US 在 AAA 监测计划中可能具有未来的补充作用。
