Family and Community Medicine, School of Medicine, University of Missouri–Columbia (Dr. LeFevre); Cascades East Family Medicine, Oregon Health & Science University, Klamath Falls (Dr. Chase) nlefevre@health.missouri.edu
The authors reported no potential conflict of interest relevant to this article.
Management options: Immediate repair or surveillance?
After diagnosing AAA, important decisions must be made regarding management, including indications for surgical repair, appropriate follow-up surveillance, and medications for secondary prevention and cardiovascular risk reduction.
EVAR vs open repair
The 2 main surgical strategies for aneurysm repair are open repair and endovascular repair (EVAR). In the United States, EVAR is becoming the more common approach and was used to repair asymptomatic aneurysms in > 80% of patients and ruptured aneurysms in 50% of patients.6There have been multiple RCTs assessing EVAR and open repair for large and small aneurysms.29-34 Findings across these studies consistently show EVAR is associated with lower immediate (ie, 30-day) morbidity and mortality but no longer-term survival benefit compared to open repair.
EVAR procedures require ongoing long-term surveillance for endovascular leakage and other complications, resulting in an increased need for re-intervention.31,33,35 For these reasons, the National Institute for Health and Care Excellence (NICE) guidelines suggest open repair as the preferred modality.7 However, SVS and the American College of Cardiology Foundation/American Heart Association guidance support either EVAR or open repair, noting that open repair may be preferable in patients unable to engage in long-term follow-up surveillance.36
Indications for repair.In general, repair is indicated when an aneurysm reaches or exceeds 5.5 cm.4,7Both SVS and NICE also recommend clinicians consider surgical repair of smaller, rapidly expanding aneurysms (> 1 cm over a 1-year period).4,7Based on evidence suggesting a higher risk for rupture in women with smaller aneurysms,14,37SVS recommends clinicians consider surgical repair in women with an AAA ≥ 5.0 cm. Several RCTs evaluating the benefits of immediate repair for smaller-sized aneurysms (4.0-5.5 cm) favored surveillance.38,39 Accepted indications for surgical repair are summarized in TABLE 3.4,7,34Surgical repair recommendations also are based on aneurysm morphology, which can be fusiform or saccular (FIGURE). More than 90% of AAAs are fusiform.40Although saccular AAAs are less common, some studies suggest they are more prone to rupture than fusiform AAAs, and SVS guidelines suggest surgical repair of saccular aneurysms regardless of size.4,41,42
Perioperative and long-term risks. Both EVAR and open repair of AAA carry a high perioperative and long-term risk for death, as patients often have multiple comorbidities. A 2019 trial comparing EVAR to open repair with 14 years of follow-up reported death in 68% of patients in the EVAR group and 70% in the open repair group. 31Among these deaths, 2.7% in the EVAR group and 3.7% in the open repair group were aneurysm related.31The study also found a second surgical intervention was required in 19.8% of patients in the open repair group and 26.7% in the EVAR group.31