Aneurysm sac shrinkage greater with fenestrated grafts


A comparison of endovascular aneurysm repair of abdominal aortic aneurysms with suprarenal fixation devices or fenestrated devices showed no difference in terms of survival and re-intervention rates. However, greater sac shrinkage was observed in the group of patients who received fenestrated grafts.

The results were presented by Filippo Maioli, Department of Vascular Surgery, Policlinico Santa Orsola-Malpighi, Bologna, Italy, at the European Society for Vascular Surgery annual meeting.


Maioli told delegates that aim of the study is to compare early and midterm outcomes of endovascular repair of abdominal aortic aneurysm with short necks performed either with standard suprarenal fixation devices (EVAR) or fenestrated devices (FEVAR). The study was conducted in the Policlinico Santa Orsola-Malpighi, in Bologna, and in the Hospital Cardiologique, CHRU, in Lille, France.


The study consisted of a review of prospectively maintained databases at these two high-volume European vascular surgery units, one performing EVAR, the other fenestrated endovascular repair. Patients with aneurysm greater than 50mm diameter and proximal neck length between 5 and 10mm treated between February 2004 and November 2009 were included. Aortic anatomy was assessed using 3D reconstruction of CT images. Follow-up imaging using ultrasound or CT angiogram was performed at one, six, 12, 18 and 24 months and yearly thereafter.


The study endpoints were survival, freedom from proximal type I endoleak, freedom from renal artery thrombosis, freedom from re-intervention and sac shrinkage.


Thirty eight EVAR and 32 fenestrated endovascular repair were performed. The EVAR devices used in the study were Cook Zenith (25), Medtronic Talent (six) and Medtronic Endurant (seven). The FEVAR cohort was treated with the Cook Zenith fenestrated device.


Fenestrated repair was more frequently associated with >50% neck circumferential thrombus and calcification (p=0.009), and short mean neck length (6.78+/-1.99mm vs. 8.53+/-1.78mm, p<0.001) and a larger mean neck diameter (27.13+/-2.45mm vs. 23.34+/-2.99mm, p<0.001).


Mean follow-up was 19.9+/-17.1 and 25.8+/-17.2 months in the EVAR and fenestrated devices groups, respectively. The one, 12, 24 and 36-month survival rate was respectively 100%, 96.3%, 86.2% and 57.4% in the EVAR group, and 96.9%, 87.4%, 78.6% and 78.6% in the fenestrated endovascular repair group (non-significant).


In the EVAR group, two (5.2%) peri-operative proximal type Ia endoleaks were detected. In the FEVAR group, one (3.1%) type Ia endoleak was diagnosed at 18 months. Renal artery thrombosis was diagnosed twice on completion angiogram in the EVAR group (5.2%). In the FEVAR group, one renal artery thrombosis was depicted on 60-month CT angiogram. Secondary intervention rates were similar in both groups. Both type Ia endoleak and secondary intervention rates were associated with critical neck angulation on multi-variate analysis. Mean aneurysm sac shrinkage during follow-up was 6.39+/-6.06mm and 10.72+/-10.79mm in the EVAR and FEVAR groups respectively (p=0.014).


Maioli said that the limitations of the investigations were that this is not a prospective randomised trial and the necks were more hostile in the FEVAR cohort.


In conclusion, he said, early and midterm outcomes results were satisfactory with both devices. “Both techniques seem to be safe and efficient in midterm follow-up. There was no difference in terms of survival and re-intervention rates,” he added. Angulation >60º and calcified and thrombosed necks are at higher risk of type Ia endoleak and re-interventions in EVAR. “Significantly more sac shrinkage was observed in the FEVAR group. Longer term follow-up is required to determine which device is more appropriate to treat aneurysms with short necks,” Maioli said.