Article
Endograft type is a risk factor for limb graft occlusion in patients treated with EVAR
Search Medline for
Authors
Published: | December 22, 2021 |
---|
Outline
Text
Background: Limb graft occlusion (LGO) is a serious complication after endovascular aneurysm repair (EVAR). In recent years, the vascular community has seen a rapid development of endograft devices enabling treatment of increasingly complex aortic anatomy yet little is published on how endograft type affects the risk of certain complications such as LGO. This retrospective study aimed to explore the incidence and risk factors associated with LGO after EVAR using the Cook Zenith Alpha, Gore Excluder and Medtronic Endurant devices.
Methods: We included all patients treated with standard EVAR, between January 2012 and December 2018, at five Swedish vascular surgery centres. LGO was defined as a total limb occlusion regardless of symptoms, or a treated significant stenosis. A nested case control (NCC) design with incidence density sampling of 1:3 was used for analysis of potential per-operative and morphological risk factors for LGO. Computed tomography angiography (CTA) imaging preoperatively and at occlusion/ postoperatively were analysed with 3Mensio Vascular for all patients included in the NCC. Conditional logistic regression was used to estimate multivariable odds ratios (OR) with 95% confidence intervals (CI). Further sub-analysis comparing outcome and morphological differences between cases and controls within the endograft device type with the highest occlusion rate was conducted.
Results: Of the 924 patients included (Zenith Alpha (n=315, ZISL limbs), Excluder (n=152, PLC/PXC limbs), and Endurant (n=457, ETLW/ ETEW limbs), 84% were male. The mean age was 76 years (7.5 SD), and median AAA diameter was 59 mm (IQR 55, 67). During median follow up of 37 months (IQR 21, 62), 55 occlusions were recorded (5.9%); of which 39 were seen with the Zenith Alpha device (12.4%), one with Excluder (0.7%), and 15 with Endurant (3.3%). In the NCC analysis, external iliac artery (EIA) landing (OR 5.91, 95% CI 1.30-26.7), EIA diameter <10 mm (OR 4.99, 95% CI 1.46-16.9) and the Zenith Alpha device (OR 5.31, 95% CI 1.97-14.3) were independent risk factors for LGO. Further detailed analysis of the cause of occlusions in patients with the Zenith Alpha device is ongoing.
Conclusion: This study concludes that endograft device type is an independent risk factor for LGO after EVAR. Specifically, the Zenith Alpha demonstrated an increased risk of LGO compared with the Endurant and Excluder devices. In addition, landing zone in the EIA and a narrow EIA and are also risk factors for LGO. Our study highlights the need for industry – independent investigations on outcomes after introduction of new medical devices.