Endovascular repair with abdominal endograft devices is used primarily to treat infrarenal abdominal aortic aneurysm. Endovascular aortic repair requires that specific anatomic criteria be fulfilled, and for those with appropriate anatomy, this technique has become a preferred approach and allows the treatment of patients who might not otherwise be candidates for aortic repair.
Endovascular aortic repair involves the insertion of endovascular graft components, usually via a femoral approach. The endovascular graft is constructed in vivo by the delivery and deployment of these components in an established order. Upon deployment, the endograft expands, contacting the aortic wall proximally and aorta or iliac vessels distally to exclude the native, dilated portion of the aortic wall from aortic blood flow and pressure.
Although there are significant variations in endovascular graft design, three types of components are common to all: the delivery system, main body device, and device extensions. Devices available in the United States to treat the abdominal aorta include the AneuRx®, Zenith®, Excluder®, AFX and Powerlink®, Talent™, and Endurant® grafts. The characteristics for each graft are described above. (See 'Abdominal devices' above.)
When aortic disease is more extensive and involves branch vessels, the complexity of the repair and risk of complications increases. Approaches to manage more complicated anatomy include debranching procedures and the use of fenestrated and branched endografts. These endografts preserve blood flow into specific aortic branches depending upon the level of repair, but are available only for investigational use in the United States.
Several trials have compared endovascular aneurysm repair with open surgical repair using a variety of endografts for the treatment of infrarenal abdominal aortic aneurysm. These trials have consistently demonstrated significantly reduced perioperative (30-day) morbidity and mortality (1 to 2 versus 3 to 5 percent) for endovascular compared with open surgical repair; however, long-term mortality is not significantly different. Secondary intervention is frequently needed in patients who receive an abdominal endograft. As such, these devices require lifelong surveillance; the long-term outcomes for these devices continue to be studied.
The few comparisons that are available for specific endograft designs for the treatment of abdominal aortic aneurysm (AAA) have found no significant differences between devices for important outcomes. Because the graft design doesn’t appear to have a major impact on the outcomes of straightforward endovascular aneurysm repair, most operators choose one endograft for routine use, reserving others for one or more features that might be better suited to a specific patient.
Characteristics of abdominal endovascular devices
| Endograft | Materials graft/support | Suprarenal fixation | Active proximal fixation/hooks | Native aortic neck diameter
(range in mm) | Native iliac diameter
(range in mm) | Maximum bifurcated main body device/introducer sheath diameter
(French, OD*) | Potential advantages |
| AneuRx® (Medtronic) | Polyester/nitinol | No | No | 20 to 26 | 8 to 22 | 21 | Hydrophilic delivery system |
| Endurant® (Medtronic) | Polyester/ electropolished nitinol | Yes | Yes | 19 to 32 | 8 to 25 | 20 | Indications include short (10 mm) aortic neck, angulated neck |
| Powerlink® (Endologix) | PTFE/cobalt chromium alloy | Yes | No | 18 to 32 | 10 to 23 | 17 | Anatomic fixation at iliac bifurcation, low profile |
| Excluder® (Gore) | PTFE/nitinol | No | Yes | 19 to 29 | 10 to 18.5 | 20 | C3 delivery system, ability to recapture and reposition body, delivery sheath with hemostatic seal |
| Talent® (Medtronic) | Polyester/nitinol | Yes | No | 18 to 32 | 8 to 22 | 24 | Indication for short (10 mm) aortic neck, angulated necks |
| Zenith® (Cook Medical) | Polyester/stainless steel | Yes | Yes | 18 to 32 | 8 to 20 | 26 | Spiral Z flexible limbs |
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