University of Florida College of Medicine, Division of Vascular Surgery & Endovascular Therapy, Gainesville, FL, USA.
Division of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, AL, USA.
Eur J Vasc Endovasc Surg. 2021 May;61(5):747-755. doi: 10.1016/j.ejvs.2021.02.018. Epub 2021 Mar 12.
As open abdominal aortic aneurysm (AAA) repair (OAR) rates decline in the endovascular era, the endorsement of minimum volume thresholds for OAR is increasingly controversial, as this may affect credentialing and training. The purpose of this analysis was to identify an optimal centre volume threshold that is associated with the most significant mortality reduction after OAR, and to determine how this reflects contemporary practice.
This was an observational study of OARs performed in 11 countries (2010 - 2016) within the International Consortium of Vascular Registry database (n = 178 302). The primary endpoint was post-operative in hospital mortality. Two different methodologies (area under the receiving operating curve optimisation and Markov chain Monte Carlo procedure) were used to determine the optimal centre volume threshold associated with the most significant mortality improvement.
In total, 154 912 (86.9%) intact and 23 390 (13.1%) ruptured AAAs were analysed. The majority (63.1%; n = 112 557) underwent endovascular repair (EVAR) (OAR 36.9%; n = 65 745). A significant inverse relationship between increasing centre volume and lower peri-operative mortality after intact and ruptured OAR was evident (p < .001) but not with EVAR. An annual centre volume of between 13 and 16 procedures per year was associated with the most significant mortality reduction after intact OAR (adjusted predicted mortality < 13 procedures/year 4.6% [95% confidence interval 4.0% - 5.2%] vs. ≥ 13 procedures/year 3.1% [95% CI 2.8% - 3.5%]). With the increasing adoption of EVAR, the mean number of OARs per centre (intact + ruptured) decreased significantly (2010 - 2013 = 35.7; 2014 - 2016 = 29.8; p < .001). Only 23% of centres (n = 240/1 065) met the ≥ 13 procedures/year volume threshold, with significant variation between nations (Germany 11%; Denmark 100%).
An annual centre volume of 13 - 16 OARs per year is the optimal threshold associated with the greatest mortality risk reduction after treatment of intact AAA. However, in the current endovascular era, achieving this threshold requires significant re-organisation of OAR practice delivery in many countries, and would affect provision of non-elective aortic services. Low volume centres continuing to offer OAR should aim to achieve mortality results equivalent to the high volume institution benchmark, using validated data from quality registries to track outcomes.
在血管腔内时代，开放性腹主动脉瘤（AAA）修复（OAR）的比例下降，因此对于 OAR 最小容量阈值的认可越来越有争议，因为这可能会影响认证和培训。本分析的目的是确定与 OAR 后死亡率降低最显著相关的最佳中心容量阈值，并确定这如何反映当前的实践。
这是国际血管登记处数据库（2010-2016 年）中 11 个国家（n=178302）进行的 OAR 的观察性研究。主要终点是术后住院死亡率。使用两种不同的方法（接受者操作特征曲线下面积优化和马尔可夫链蒙特卡罗程序）来确定与死亡率显著改善最相关的最佳中心容量阈值。
总共分析了 154912 例（86.9%）完整和 23390 例（13.1%）破裂的 AAA。大多数（63.1%；n=112557）接受了血管内修复（EVAR）（OAR 36.9%；n=65745）。完整和破裂的 OAR 后，中心容量增加与围手术期死亡率降低呈显著负相关（p<0.001），但 EVAR 则不然。每年中心容量在 13 至 16 例之间与完整 OAR 后死亡率降低最显著相关（调整后的预测死亡率<13 例/年为 4.6%[95%置信区间 4.0%-5.2%]，≥13 例/年为 3.1%[95%CI 2.8%-3.5%]）。随着 EVAR 的日益采用，每个中心的 OAR 数量（完整+破裂）显著减少（2010-2013 年=35.7；2014-2016 年=29.8；p<0.001）。只有 23%的中心（n=240/1065）达到了≥13 例/年的容量阈值，各国之间存在显著差异（德国 11%；丹麦 100%）。
每年 13-16 例 OAR 的中心容量是与完整 AAA 治疗后死亡率降低最显著相关的最佳阈值。然而，在当前的血管腔内时代，要达到这一阈值，需要在许多国家对 OAR 实践的实施进行重大调整，并会影响非选择性主动脉服务的提供。继续提供 OAR 的低容量中心应努力达到与高容量机构基准相当的死亡率结果，使用来自质量登记处的经过验证的数据来跟踪结果。
