SVS Publishes Updated AAA Guidelines
December 18, 2017—The Society for Vascular Surgery (SVS) announced the publication of the first update in 9 years to the SVS clinical practice guidelines for the care of patients with an abdominal aortic aneurysm (AAA), which address both endovascular aneurysm repair (EVAR) and open surgical repair. The guidelines, by Elliot Chaikof, MD, et al, are available online at vsweb.org/AAAGuidelines. Additionally, the document will be published in full in the January issue of the Journal of Vascular Surgery, accompanied by an editorial by the journal’s editors.
According to SVS, the guidelines include revisions to several older recommendations and address new topics. The guidelines are supported by three systematic reviews and meta-analyses prepared by the Evidence-Based Practice Center at the Mayo Clinic in Rochester, Minnesota. SVS noted that this is one of the longest set of guidelines the society has ever published. Previous AAA practice guidelines were published in 2003 and 2009 by SVS in the Journal of Vascular Surgery.
In the 2018 updated guidelines, authors made specific practice recommendations using the Grading of Recommendations Assessment, Development, and Evaluation system, a formal method to assess certainty of the underlying evidence, and concluded with recommendations for further research.
There are 111 recommendations in the document. For the first time, an SVS clinical practice guideline has recommended that procedures should be limited to centers that meet a specific case volume threshold and outcome target. These guidelines set a minimum number of AAA procedures per year at each hospital that offers the procedure. This recommendation was discussed at length and now represents a balance between the available evidence and the different practice patterns and environments in which SVS members work.
Under these recommendations:
1. Elective EVAR should be performed in hospitals with a documented mortality and conversion rate to open surgical repair of ≤ 2% and that perform at least 10 EVAR cases per year. Open AAA should be performed in hospitals with a mortality rate < 5% and that perform at least 10 open repairs per year.
Thomas Forbes, MD, Chair of the SVS Document Oversight Committee, commented in the announcement, "This volume requirement prompted much discussion among academic and community surgeons alike. The original suggestion was for higher volume numbers, but eventually epidemiologically sound and clinically relevant case volumes were set to recognize the excellent work that SVS members are doing in a variety of practice settings. We recognize that these case volume requirements are open to discussion and will likely be revisited in future updates to these guidelines.”
2. The guidelines recommend that surgeons should use the SVS Vascular Quality Initiative (VQI) mortality risk score to assist in making informed decisions and recommendations about aneurysm repair. Dr. Forbes explained, “This allows the physician to give a patient-centered and personalized risk prediction, rather than use mortality risks from trials involving other patients.
3. Endovascular repair is preferred over open repair for treating ruptured aneurysms if anatomically feasible. Dr. Forbes noted, "Randomized trials for this are very difficult to do. When this guideline was being developed, there [were] a paucity of randomized trial data to support this; however, there [were] a great deal of registry, single-center, and multicenter data in support, as well as expert opinion. Recently, the midterm data from the IMPROVE trial has been published and is in support of this recommendation.”
SVS also highlighted other recommendations:
- A door-to-intervention time of < 90 minutes for emergency repairs
- A one-time AAA ultrasound screening for men and women aged 65 to 75 years who have a history of tobacco use (several other societies recommend screenings for male smokers only)
- Recommendations for the treatment of endoleaks
- Appropriate use of antibiotic prophylaxis in patients with an aortic prosthesis undergoing dental and other invasive procedures
Vascular surgeons worldwide will welcome the updated guidelines, Dr. Forbes stated, adding, “It’s a huge resource. These guidelines are the new key reference for aneurysm therapy, and this update provides background and clear direction. There is nothing else like it. It is the hallmark of guidelines.”