12-Month Results
Rodolfo Pini, Claudio Bianchini Massoni, Gianluca Faggioli, Stefania Caputo, Gemmi Sufali, Stefano Ancetti, Andrea Vacirca, Enrico Gallitto, Paolo Perini, Antonio Freyrie, Mauro Gargiulo, Kimihiro Komori, MD, PHD, Shinsuke Nanto, MD, PHD, Erin E. O’Leary, PHD, Aaron E. Lottes, PHD, Scott A. Snyder, PHD, Michael D. Dake, MDh
WHAT THIS PAPER ADDS
In the literature, many experiences with different rates of limb graft occlusion (LGO) in endovascular aortic
aneurysm repair (EVAR) are reported. Some authors have identified the Cook Zenith Alpha endograft as an
independent risk factor for LGO. The present study analysed the rate of LGO according to a standard protocol for
minimising limb complications. With a mean follow up of 44 months, four LGOs occurred in 233 Zenith Alpha
grafts (1.7%) resulting in a 97% freedom from LGO at five years, with no differences compared with other types
of endograft. Two independent risk factors associated with LGO were identified with Cook Zenith Alpha
endograft: the external iliac artery distal landing zone and the use of a large main body (ZIMB 32 e 36).
Objective: Numerous articles have reported an increased incidence of limb graft occlusion (LGO) with the Cook Zenith Alpha endograft compared with other endografts in endovascular aortic aneurysm repair (EVAR). The present study aimed to assess the rate of LGO after EVAR in particular with the Cook Zenith Alpha device when adhering to a standardised protocol designed to prevent limb related complications.
Methods: This was a non-sponsored retrospective study performed in two university vascular surgery centres employing the same protocol for limb complication prevention during EVAR from 2016 to 2019. The protocol encompassed: (1) angioplasty of any common or external iliac artery with > 50% stenosis before endograft navigation; (2) proximal sealing zone of limbs at the same level of the flow divider with minimum overlap, which is more restrictive than the Cook Zenith Alpha instructions for use; (3) semi-compliant kissing ballooning of limbs; (4) limb stenting for any residual tortuosity, kinking, or stenosis; and (5) adjunctive common and external iliac stenting for residual stenosis or dissection after EVAR. Patients enrolled in this study were treated with standard aortobi-iliac EVAR. Follow up was performed by clinical visit and duplex ultrasonography at discharge, six months, and yearly thereafter. The primary endpoint was to evaluate the LGO rate with different EVAR devices (Cook Zenith Alpha, Gore C3, and Medtronic Endurant) and to determine potential risk factors for LGO associated with the Zenith Alpha.
Results: In the study period, 547 EVARs were considered: 233 (42.6%) Cook Zenith Alpha, 196 (35.8%) Gore Excluder, and 118 (21.6%) Medtronic Endurant. The mean follow up was 44 23 months, and the five year freedom from LGO was 97 3%, without differences between groups (97 2%, 95 3%, and 100% with Cook Zenith Alpha, Medtronic Endurant, and Gore Excluder, respectively; p ¼ .080). In the Zenith Alpha group, intraoperative adjunctive iliac artery angioplasty, iliac artery stenting, or iliac limb stenting was performed in 8%, 3.4%, and 9.7% of cases, respectively. Analysis of potential risk factors for LGO identified external iliac artery distal landing and large main bodies (ZIMB 32 e 36) to be independently associated with LGO during follow up (hazard ratio [HR] 18, 95% confidence interval [CI] 3 e 130, p ¼ .004; and HR 12, 95% CI 1.2 e 130, p ¼ .030, respectively).
Conclusions: The present experience with a protocol for limb complication prevention allows achievement of a low rate of LGO at five years with Zenith Alpha endografts similar to other endografts. Specific risk factors for the Cook Zenith Alpha endograft are external iliac artery distal landing and the use of a large main body (ZIMB 32 e 36).
