Comparative Study of Endovascular Aneurysm Repair in Patients with Narrow Aortic Bifurcation Using the Unibody AFX2 vs the Bifurcated ALTO Endoluminal System

<b>Objectives:</b> A narrow aortic bifurcation poses technical challenges during endovascular aneurysm repair (EVAR). We aim to compare the unibody AFX2 (Endologix, Irvine, CA, USA) vs the bifurcated ALTO (Endologix) system in EVAR patients with a narrow bifurcation. <b>Methods:</b> Retrospective single-center study, including patients undergoing standard EVAR over 3 years. Patients with a bifurcation diameter <20 mm were identified, and outcomes were compared between the AFX2 and ALTO groups. Primary endpoints were primary and overall technical success, primary and overall clinical success, rate of adverse limb events, rate of limb occlusion, and need for secondary interventions. The analysis was repeated using a diameter threshold of <18 mm. <b>Results:</b> Among 151 cases, 26 presented with bifurcations <20 mm and 12 with <18 mm. In the primary analysis, 15 patients were treated with the AFX2 and 11 with the ALTO endograft. Both groups achieved 100% technical and clinical success. No limb occlusions occurred, and no reinterventions were recorded. Preoperative anatomy was suitable for ALTO in all cases, while eligibility for AFX2 was 15 out of 26 cases. Secondary analysis displayed similar results. <b>Conclusions:</b> In patients with narrow aortic bifurcation, the AFX2 endograft can be safely used when appropriate anatomic conditions are met. If the AFX2 system is unsuitable due to other anatomic restrictions, the ALTO endograft is a viable alternative.