A new nonstented balloon-expandable graft for straight or bifurcated endoluminal bypass.

Abstract

The aim of this study was to determine the feasibility of endoluminal grafting of aneurysms using a new design of nonstented endograft. Initial studies were undertaken in bench models and by implantation of endografts into animal vessels. Between May 1992 and June 1994, endoluminal repair of aneurysms was undertaken in 47 patients (44 male, 3 female). A new balloon-expandable endoluminal graft was developed and has now been studied in 25 of these 47 cases. This graft does not require adjunctive use of a vascular stent because of its unique construction, which incorporates metallic implants (graft attachment device or "GAD") into the graft material. The design is applicable to endovascular grafting of occlusive arterial disease, as well as aneurysms. All patients were investigated by duplex scan, calibrated angiogram, and angio-CT scan and then allocated into groups that we defined according to the following criteria: group I, considered suitable for transfemoral implantation of a straight tube graft (n = 12); group II, unsuitable for transfemoral tube graft because of short neck of aneurysm, absent distal neck, or diseased iliac arteries (n = 10); and group III, peripheral aneurysms (n = 3). All patients were followed by clinical examination, duplex scan, and CT scan, with selective use of angiography. Intraluminal deployment of the graft was achieved in all 25 patients; however, 3 patients from group II subsequently required conversion to open procedures because of the following complications: (1) partial graft thrombosis resulting from inadvertent omission of systemic anticoagulation during deployment (n = 1); and (2) unsuccessful deployment of the contralateral limb of a bifurcated graft in the iliac artery (n = 2). Successful endoluminal repair was achieved in 100% of patients in groups I and III, compared to 70% in group II. These preliminary results (in a series of high-risk patients) have demonstrated that endoluminal abdominal aortic aneurysms repair with this graft can be achieved reliably and with low morbidity in patients who fulfill the selection criteria (group I) and in peripheral aneurysms (group III) but the results were less satisfactory in aneurysms that do not have a good proximal or distal neck or in patients with diseased iliac arteries (group II). Further modification of the bifurcated version in this graft design, together with improvements in access techniques and graft materials, is required for successful endoluminal grafting in a wider range of patients.