Endograft Anaconda in Endovascular Aneurysm Repair: A Systematic Review of Literature and Meta-Analysis

Abstract

The number of endovascular abdominal aortic aneurysm repairs (EVARs) has surpassed the number of open surgical repair of AAAs worldwide with a great variety of endografts being available. The aim of this study is to conduct a systematic review of the literature and meta-analysis of studies reporting patients with infrarenal abdominal aortic aneurysm (AAA) subjected to EVAR with the Anaconda endograft. We performed a systematic review of multiple electronic databases for studies including patients with infrarenal AAA who were subjected to elective EVAR with Anaconda endograft exclusively. We conducted a proportional meta-analysis cumulating the results of the included studies. The endpoints were first month overall mortality, first and second-year survival after EVAR, AAA-related deaths, incidence of endoleaks, endograft migration, endograft occlusion, open conversion, and primary and secondary technical success. The mean valuefor each separate studied factor was calculated, and the respective percentage or incidence was extracted so that it can be compared to endograft outcome studies in the literature. We assessed the methodologic quality of studies by using the Briggs Institute critical appraisal tool. Seven observational studies were found including 954 patients (males 91.9%, mean age 73.38±6.97years). The mean transverse diameter of AAAs was 56.83±9.97mm. The mean proximal aortic neck diameter and length were 23.06±3.33mm and 24.14±12.16mm, respectively. Increased aortic neck calcification and aortic neck thrombus were present in 12.5% of patients. The 30-day overall mortality post-EVAR was 1.3%, 1 and 2-year survival rates were 95.9% and 91.4%, respectively. The mean follow-up period in the studies was 46.59±15.5months. AAA-related mortality was 1.3%. Primary technical success was 97.9% and secondary success was 99.3%. Open conversion was required in 3.4% of all patients (0.6% during the primary operation [Prim. Op]). The most common endoleak was type II, reported in 17.4% of all patients. Early type Ia endoleak was reported in 1.5% of patients andlate type Ia in 1.7%. Overall, 2 endoleaks type III and 1 type IV were reported. Endograftmigration occurred in 1.7% of patients. Main body and/or one/both iliac legs thrombotic occlusion was found totally in 7.6% of patients (5 main body occlusions and 64 iliac leg occlusions). The use of Anaconda endograft in electively treated patients with infrarenal AAAs presented good results with high technical success and low postoperative and mid-term complications, except for an increased incidence of stent-graft thrombosis, which seems to be the "Achilles heel" of the device.