Endovascular aortic aneurysm repair in patients with narrow aortas using bifurcated stent grafts is safe and effective

Abstract

Narrowing of the distal aortic bifurcation can result in stent graft compression or arterial disruption during endovascular aortic aneurysm repair (EVAR). The aim of our study was to evaluate results of EVAR in patients with narrow distal aortic bifurcations. We reviewed the clinical data of 1070 patients who underwent EVAR between 2000 and 2011. Digital computed tomography angiograms were analyzed using centerline of flow measurements to determine aortic diameters. Patients with a distal aortic bifurcation diameter <18 mm were included in the study. End points were technical success, aortic disruption with retroperitoneal hemorrhage, stent graft complications (endoleaks, migration, sac enlargement, stenosis), reintervention, and iliac limb patency. EVAR was used to treat 112 patients (84 men and 28 women; mean age, 75 years) with aortic bifurcation <18 mm, including 34 (30%) who had diameter of <14 mm. Mean outer and inner aortic bifurcation diameter was 16 ± 3 and 14 ± 2 mm, respectively. Bifurcated stent grafts were used in 106 patients (95%). Six patients (5%) had planned aortouniiliac converters with femoral crossover graft. The aortic bifurcation was dilated after placement of bifurcated stent grafts using kissing balloon angioplasty in 80 patients (75%). All bifurcated stent grafts were successfully implanted, with no conversions to open repair or aortouniiliac converters. There were two early deaths (1.8%), and 12 patients (11%) developed early complications. No aortic disruptions or retroperitoneal hematomas occurred in the group treated with bifurcated grafts. After a median follow-up of 35 months, 11 patients (11%) treated by bifurcated stent grafts required reintervention to treat endoleak (n = 6) or iliac limb stenosis/occlusion (n = 5). One patient (17%) treated by aortouniiliac converter developed critical stenosis of an aortouniiliac graft limb, which was successfully treated with balloon angioplasty 29 months after the initial surgery. At 1 and 5 years, freedom from reintervention was 91% ± 3% and 84% ± 4%, respectively, for bifurcated stent grafts and 100% and 83% ± 10%, respectively, for aortouniiliac converters. Primary and secondary iliac limb patency was 98% ± 3% and 100%, respectively, for bifurcated stent grafts and 83% ± 10% and 100%, respectively, for aortouniiliac converters. EVAR with bifurcated stent grafts is safe and effective in patients with a narrow distal aortic diameter, even when the aortic bifurcation measures <14 mm. Adjunctive balloon dilatation did not result in any bleeding complications from aortic disruption, and limb patency was excellent. Aortouniiliac converters are rarely needed for this indication.