Outcomes following open aortic surgery in the endovascular era
The introduction of new surgical technology, however, usually adds to the surgeon's armamentarium rather than depleting it, but importantly may later drive a paradigm shift in the management of surgical disease. This often requires surgeons to adapt and become proficient in new skills throughout their career, possibly at the expense of others. Examples include robotic surgery in urology, arthroscopy in orthopaedics and laparoscopy in general surgery.
The evolution of endovascular techniques has revolutionized vascular surgery, resulting in a dramatic shift away from open surgery towards minimally invasive interventions, exemplified by the treatment of abdominal aortic aneurysms (AAA). Following the introduction of endovascular aneurysm repair (EVAR) in the early 1990s, the proportion of AAA treated with EVAR has risen to over 70%, with a consequential decline in open AAA repair (oAAA). Over this period of time established surgeons have had to learn new endovascular skills ‘on‐the‐job’, whilst newer vascular trainees have had the advantage of exposure to both open and endovascular procedures. Contemporary vascular trainees are predominantly exposed to endovascular interventions, with a dramatic reduction in the number of open aortic cases available to trainees. To compound matters, unfavourable anatomy precluding EVAR results in more challenging open surgery less appropriate for training. This has raised concerns regarding the ability of both current and future vascular surgeons to safely perform increasingly rare and complex open aortic surgery.1
Beiles and Walker2 addressed these concerns by investigating the mortality following oAAA by Australasian surgeons trained in the endovascular era compared to a more senior group. They interrogated the Australasian Vascular Audit analysing 11 455 aneurysm repairs, including 4046 oAAA. Using Australian Institute of Health and Welfare data, they confirmed that the proportion of open repairs had fallen from 72% in 2000 to 24% in 2014. However, they found no statistically significant difference in mortality in elective oAAA between the two groups. Although mortality was found to be higher in ruptured aneurysms repaired by the younger group, this failed to reach statistical significance in multivariate regression analysis. Furthermore, the study confirmed that the younger group was performing a higher proportion of more complex aneurysm surgery as demonstrated by the percentage of juxtarenal aneurysms repaired. The authors concluded that vascular training in aortic surgery in Australasia had not been significantly impaired by the introduction of endovascular techniques despite fewer open procedures.
These findings corroborate several earlier reports from single centres in the United States, Europe and Japan. They all reported a sharp decline in the frequency of oAAA, but with comparable and acceptable mortality rates before and after the introduction of EVAR programmes, despite an increase in complexity of oAAA. These consistent findings are particularly interesting considering inconsistencies in vascular training across the globe. In Australasia, vascular surgery separated from general surgery over 15 years ago, reflecting in part the early adoption and innovation of endovascular techniques. In the United States, pure vascular training programmes were introduced in 2006, with the majority still including general surgery rotations. In the UK, vascular surgery only became an independent surgical specialty in 2013. Despite these differences in vascular training, the introduction of EVAR worldwide appears not to have had a significant negative influence on outcomes following oAAA to date. However, it is worth reflecting that the endovascular era has been relatively short, with many contemporary vascular surgeons benefiting from training during the overlap between open and endovascular eras.