Andrew Holden, Auckland, New Zealand, presented results from the preliminary clinical experience with the Ventana off-the-shelf fenestrated endovascular graft (Endologix) yesterday.
“Between 25 and 40% of infra-renal abdominal aortic aneurysms are not amenable to endovascular aneurysm repair (EVAR) using currently available devices,” Holden told delegates at an Endologix sponsored event. “The most common reason is inadequate infra-renal aortic neck anatomy (short neck or neck with adverse features such as reverse conical shape or thrombus,” he said.
Fenestrated EVAR devices (FEVAR) have been developed to treat a greater number of juxta-renal abdominal aortic aneurysm morphologies by extending the graft sealing zone into the supra-renal visceral artery segment. “Published data have shown that FEVAR is associated with lower 30-day mortality and post-procedure renal impairment when compared to open repair,” Holden stated.
Current FEVAR devices are customised for individual patients. The planning, construction and delivery of these devices inevitably results in procedural delays, he said. “To manage this problem, Endologix has developed the first ‘off-the-shelf’ FEVAR device with steerable fenestrations to be used in clinical practice, the Ventana fenestrated endograft.”
Holden explained that the Ventana device has two 3mm diameter renal fenestrations with renal sheaths pre-loaded through the fenestrations. The fenestrations can be dilated up to 8mm diameter and can be moved up to 35mm from their nominal locations. There is a 4cm deep scallop for the coeliac artery and superior mesenteric artery. The Ventana Fenestrated Proximal Extension Graft is delivered after an Endologix Powerlink bifurcated graft has been deployed with anatomic fixation at the aortic bifurcation.
“There are some anatomic eligibility requirements, the most important being an ‘infra-superior mesenteric artery neck’ length of 15mm or longer,” Holden said. “A key feature of the device is that it is fully constrained while the renal arteries are being cannulated – this facilitates quick and easy cannulation of even challenging renal artery anatomies. Covered balloon expandable stents are deployed into the renal arteries to create what are essentially branch grafts. In recent cases, the Endologix Xpand covered stents have been used.”
To date, nine patients have been treated with the Ventana system (six in Auckland and three in Santiago, Chile). There have been no major adverse events, 100% technical success, 0% mortality and 0% conversion to open repair.
“Procedural times have been very satisfactory given a ‘first in man’ trial. Seven patients have had a CT scan one month after repair – there has been 100% freedom from type I or type III endoleak and all branch arteries are patent. Interestingly, all patients have received a Ventana model where the renal fenestrations are ‘aligned’ – six have received a device with a proximal diameter of 28mm and three with a proximal diameter of 24mm,” Holden said.
In conclusion, he said, “the Endologix Ventana Fenestrated Graft offers an exciting ‘off-the-shelf’ FEVAR device for the management of juxta-renal abdominal aortic aneurysms. Early clinical experience has been excellent.”
Two designs fit 90% of patients
Another off-the-shelf fenestrated graft is Cook Medical’s device. “It is safe to say that an off-the-shelf design would alleviate a lot of issues,” Timothy Resch, Malmo, Sweden, told the audience during the Cook satellite symposium yesterday.
He said that Cook’s off-the-shelf fenestrated device has a three-piece modular design: the proximal component which is tubular with fenestrations; the second component which is bifurcated without a top cap; and the contralateral limb.
“The device is based on the fenestrated platform that we have used successfully for elective patients. It is very similar in design and incorporates a lot of those features that we know have created stability over time,” Resch said.
“There is a good advantage in having only unilateral access for the renal arteries and all the small sheaths. With two designs we can fit about 90% of patients.
The preloaded wire through the renal fenestrations is very helpful, and the self retrieving top cap makes the procedure easier as well.”
Resch said the device may be available by the end of the year.