The outcome of endovascular repair of small abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) affects approximately 5% of men and 1% of women over 60 years, and the incidence is increasing.1 The principal complication of AAA is aortic rupture, which usually results in death.2 Rupture risk is presently best predicted by aortic diameter, with AAAs >6 cm having a rupture risk of approximately 10% per year.3 Since AAA is usually asymptomatic, the condition is often diagnosed as an incidental finding during abdominal imaging. Recently, a number of randomized controlled trials have demonstrated that ultrasound screening of selected population can reduce deaths associated with AAA.4,5 The more widespread use of ultrasound screening and abdominal imaging has led to an increase in the number of small AAAs referred for management. Two randomized trials have supported a conservative policy for small AAAs, whereby following identification aneurysms are followed by ultrasound surveillance unless the aneurysm expands to >5.5 cm in maximal diameter when surgery is advised.6,7 The introduction of endovascular aneurysm repair (EVAR) has made available a less invasive surgical option, which had been demonstrated to be associated with lower perioperative mortality than open surgery for the repair of large aneurysms.8,9 However, EVAR has a number of complications that only become apparent during longer-term follow-up, such as late aortic rupture, endoleak, graft migration, and graft limb occlusion.10,11 Intermediate follow-up of patients randomized to EVAR for the treatment of large AAAs demonstrated no reduction in all-cause mortality in comparison to open surgery and increased requirement for reintervention.10,11 The favorable perioperative results, the greater anatomic suitability and the belief that the outcome of EVAR is better have all encouraged the extension of this technique to patients normally treated conservatively with small AAAs. The aim of this study was to examine the perioperative and intermediate results of EVAR for AAAs of ≤5.5 cm.