Total Viabahn Endoprosthesis Collapse

Objectives: Although open surgical repair remains the standard, endovascular repair of popliteal artery aneurysms with covered stent-grafts is increasingly being utilized. Emerging technologies present unique complications. We present the first case of total Viabahn endoprosthesis collapse during the treatment of a PAA.
Methods: An elderly male with severe comorbidities presented with a left PAA 34mm in maximum diameter. Pre-operative CTA demonstrated 11mm and 9mm proximal and distal landing sites respectively. Intraoperative angiography correlated with pre-operative CTA. Five Viabahn grafts were deployed. Post-deployment angiography revealed no endoleak but a filling defect in the distal popliteal graft with poor flow on delayed images. Angiography with the knee bent revealed cessation of flow. Balloon dilatation failed. The procedure was converted to an open femoral-to-popliteal bypass with aneurysm ligation. Transection of the distal popliteal vessel demonstrated infolding with incomplete expansion of the Viabahn graft.
Results: Our choice of grafts represented 15%-18% proximal and distal oversizing, well within the device IFU. We speculate that areas of scattered, non-circumferential calcification, not fully appreciated on imaging, led to relative vessel narrowing. This focal gross oversizing of the Viabahn graft ultimately led to infolding and failure. Liberal use of pre-deployment angioplasty may have been useful.
Conclusion: Meticulous sizing of the entire target vessel is critical to successful deployment. Focal areas of relative vessel narrowing may lead to graft failure and careful attention to these areas prior to device deployment may improve technical success.