Kindon Andrew J, McCombie Andrew M, Frampton Chris, Khashram Manar, Clarke Glynnis, Roake Justin
Geo-Health Laboratory, University of Canterbury, New Zealand; Department of Radiology, Christchurch Public Hospital, Canterbury District Health Board, New Zealand; Christchurch Vascular Group, Christchurch, New Zealand.
Department of Surgery, University of Otago, New Zealand.
Eur J Vasc Endovasc Surg. 2023 Dec;66(6):797-803. doi: 10.1016/j.ejvs.2023.08.006. Epub 2023 Aug 9.
This study aimed to test whether the relative growth rate of subthreshold abdominal aortic aneurysms (AAAs) in the first 24 months of surveillance predicts the risk of future rupture or repair.
This was a single centre retrospective observational analysis of all small (< 45 mm diameter) and medium (45 - 54 mm in men, 45 - 50 mm in women) AAAs entered into ultrasound surveillance between January 2002 and December 2019, which received ≥ 24 months of surveillance. Relative growth rates were calculated from measurements taken in the first 24 months of surveillance. The Kaplan-Meier method was used to estimate intervention and rupture free proportions five years following diagnosis for AAAs growing by < 5% and by ≥ 5% in the first 24 months of surveillance. Multivariable Cox regression analysis was used to further analyse this relationship by adjusting for factors found to be significantly associated with outcome in univariable analysis.
A total of 556 patients with AAAs (409 men, 147 women) were followed for ≥ 24 months. This included 431 small AAAs. Of these, 109 (25.3%) grew by < 5% in the first 24 months of surveillance and had a cumulative event free proportion of 0.98 ± 0.05 at five years compared with 0.78 ± 0.05 for the ≥ 5% growth group (p < .001). Of 125 medium AAAs, 26 (20.8%) grew by < 5% in the first 24 months of surveillance and had a cumulative event free proportion of 0.73 ± 0.11 at five years compared with 0.29 ± 0.13 for the ≥ 5% growth group (p = .024). Baseline diameter and early relative growth rate were strongly and independently predictive of future intervention or rupture with hazard ratios of 9.16 (95% CI 5.98 - 14.03, p < .001) and 4.46 (95% CI 2.45 - 8.14, p < .001), respectively.
The results suggest that slow expansion of small (< 45 mm) AAAs observed over an isolated 24 month period is indicative of a very low risk of rupture or repair in the medium term. Isolated growth rates may be a useful tool with which to triage low risk AAAs and prevent unnecessary surveillance.
本研究旨在测试亚阈值腹主动脉瘤（AAA）在监测的前24个月内的相对生长速率是否能预测未来破裂或修复的风险。
这是一项单中心回顾性观察分析，对象为2002年1月至2019年12月期间接受超声监测且监测时间≥24个月的所有小（直径<45mm）和中（男性45 - 54mm，女性45 - 50mm）型AAA。相对生长速率根据监测前24个月的测量值计算得出。采用Kaplan-Meier方法估计在监测的前24个月内生长<5%和≥5%的AAA在诊断后五年的干预和无破裂比例。多变量Cox回归分析用于通过调整单变量分析中发现与结局显著相关的因素来进一步分析这种关系。
共有556例AAA患者（409例男性，147例女性）接受了≥24个月的随访。其中包括431例小型AAA。在这些小型AAA中，109例（25.3%）在监测的前24个月内生长<5%，五年时累积无事件比例为0.98±0.05，而生长≥5%的组为0.78±0.05（p<0.001）。在125例中型AAA中，26例（20.8%）在监测的前24个月内生长<5%，五年时累积无事件比例为0.73±0.11，而生长≥5%的组为0.29±0.13（p = 0.024）。基线直径和早期相对生长速率对未来干预或破裂具有强烈且独立的预测性，风险比分别为9.16（95%CI 5.98 - 14.03，p<0.001）和4.46（95%CI 2.45 - 8.14，p<0.001）。
结果表明，在单独的24个月期间观察到的小（<45mm）型AAA的缓慢扩张表明中期破裂或修复风险非常低。单独的生长速率可能是一种有用的工具，可用于对低风险AAA进行分类并防止不必要的监测。
