Reviews of the Lombard Medical Aorfix AAA Stent Graft System | Which Medical Device

Introduction

Early experience with the Aorfix^TM graft has been described in a previous review. Since then a large worldwide experience has been gained with the graft and initial learning curve issues with graft planning and deployment techniques overcome. 

Design/construction

Aorfix^TM is a 2 part modular graft with a helical circular nitinol frame covered by a woven polyester fabric, resulting in an extremely flexible and conformable graft.
The proximal and distal graft rings form a fishmouth shape when appropriately oversized.There are proximal hooks  for infra renal fixation.The graft has limited column strength which enhances its flexibility but needs to be supported during deployment with longitudinal push rods.

In use

1) Graft planning 

Sizing of the Aorfix is more critical than with many other grafts as over sizing of greater than 15% may lead to incomplete opening of the proximal or distal fish mouth and potential luminal narrowing.Graft oversizing to a maximum of 10-15% is recommended.

Given the grafts flexibility it may shorten in tortuous anatomy.Generous limb lengths are therefore recommended particularly as the legs can be shortened by 1-2 cm during deployment.
 
2) Graft deployment 

Proximal graft deployment should start high above the renal vessels with careful orientation of the fishmouth configuration of the top of the graft.The graft can be pulled down but not easily advanced upwards.Experience has show that the push rods which support the proximal graft during deployment should not be advanced to dilate the proximal graft in angulated anatomy as they can distort the proximal graft.
With experience the graft can be placed accurately below the renal arteries often with the peaks of the fishmouth extending superiorly to allow a degree of trans-renal fixation.

Results so far

There has been an initial learning curve with the Aorfix mainly related to avoiding oversizing the graft and avoiding using the push rods in angulated anatomy.
Despite this patient outcomes have been good. In our centre over 35 cases have been performed to date often in difficult anatomy-(neck angles >60⁰ in 17/35 and iliac angulation >90⁰ in 18/35). No 30 day mortality, late endoleaks or limb occlusions have occurred.
 
Wordwide over 1000 implants have been performed.
The latest RADAR registry data (753 patients) showed a 30d mortality of 1.6%, with low type 1 endoleak rates and a incidence of limb occlusions of less than 0.3%.

Following a prospective multi centre observational study (ARBITER2) for patients with 60-90⁰ necks Aorfix now has CE marking to treat neck angles up to 90⁰

Conclusions

Pros:
Highly flexible graft that enables EVAR to be performed safely and with good clinical outcomes in angled and standard anatomy
 
Cons:
limited size range.
accurate proximal deployment in short necks is not as reliable as some other grafts.

Dr John Hardman, Consultant Interventional Radiologist
Bath, UK

Conflict of Interest:

Dr John Hardman has been paid fees for speaking and consulting by Lombard Medical