Graft designs hot topic at Critical Issues Symposium


The latest issues surrounding endovascular aortic repair and carotid stenting was discussed at the recent 9th International Symposium on Critical Issues in Endovascular Grafting in Frankfurt, Germany. In a lively discussion entitled, ‘Different Grafts – different designs: What you do not read in brochures’, world-renowned surgeons provided their views on various stents designs.

Stefano Gennai, Ospedale S.Agostino, Modena, Italy, presented the results of the PowerLink (Endologix) AAA stentgrafts. The results demonstrated that the PowerLink system had excellent stability (no migrations) and resistance of materials to fatigue. In addition, rapid deployment was seen in favourable anatomies. However, deployment does require a learning curve and use of the stent graft in bad anatomies (angulated necks) is not advisable.

Despite this, Gennai said the stent graft had low endoleak and conversion rate and the new short limbs (4cm) allowed landing on the bifurication. In addition, it was noted that an improvement in the flexibility and tip of the delivery system would permit an extension of the device in more tortuous anatomies.

Following Gennai, Dr Dieter Raithal, Vasculare und Endovasculare Chirurgie, Nurnberg, Germany, presented the results from his experience with the Ancure (Guidant) AAA stent graft. He reported a primary technical success rate of 99.4% with 0% mortality, low endoleakage rate and no significance in the limb occlusion rate. Raithal concluded that the Ancure system was safe and effective for endovascular AAA repair and its design (endo-hook-system) achieved adequate hemostatic seal and sufficient endogaft fixation. There have been no attachment system failure to date and there are more advantages than disadvantages.

Next, Hardy Schumacher, Department of Vascular Surgery, Heidelberg, Germany, discussed the LifePath system (Edwards Lifesciences) designed to be to be an optimised balloon expandable endograft. Incorporated in to the design were a compression seal with an established force equilibrium between the stent and the arterial wall. The results for a multicentre trial assessing the system revealed an implantation success rate of 98.7% (224/227), with a 30-day mortality rate of 1.3% (n=3). The trial also revealed no post-operative aneurysm ruptures or modular separation.

Following the presentations, Dr Peter Harris, Royal Liverpool Hospital, UK, commented that although there have been good results for two devices that were withdrawn (Ancure and LifePath) and good results for two additional devices (Anaconda [Vascutek] and PowerLink), these devices have not set the world alight.

Also speaking at the Critical Issues Symposium was Professor Giovanni Torsello of St Franziskus-Hospital, Muenster, Germany, who discussed seven-year durability of Medtronic’s Talent stent-graft.

Speaking on behalf of the Talent abdominal aortic aneurysms (AAA) Retrospective Long-Term (TARL) study group, Torsello presented on ‘One graft beyond five years: The German Talent Registry’.

He began by discussing the study background for the TARL study, explaining that less data is available on long-term clinical outcomes of endovascular aneurysm repair (EVAR) using still available stent-grafts. Due to availability of larger sizes and its column strength, the Talent stent-graft has frequently been used in Germany since 1996, Torsello explained. The TARL study aims to assess the long-term clinical and radiographic outcome after implantation of Talent stent-graft for AAA, as well as investigating the durability of EVAR for treatment of AAA with available stent-grafts.

The retrospective, multicenter study followed-up patients who had a Talent stent-graft implanted before the end of 1998. Over the seven year period, patient outcomes saw two (1.2%) lost to 30-day mortality and 28 (17%) to late mortality, 12 (7.2%) lost to follow-up, two (1.2%) lost to aneurysm rupture during follow-up and one (0.6%) lost to aneurysm related mortality. Of the causes of death, 15 (50%) were due to cardiac failure, five to a tumor, one to AAA rupture, eight to other reasons and one (3.3%) to unknown reasons.

Torsello concluded that after a follow-up of up to seven years, AAA rupture death was prevented in all but one case. In comparison with grafts of the first generation, the device showed good durability as long as five to seven years after implantation.

He also said the Talent stent-graft was successfully in patients with short and wide necks; that old patients should not refused for treatment; and that because of the potential need for secondary interventions, life-long follow-up is recommended.