CHICAGO – Real-world 30-day outcomes with the Zenith fenestrated endovascular graft compared well with those in the U.S. fenestrated trial for the treatment of juxtarenal aortic aneurysms, based on a multicenter, retrospective study of 57 patients.
The good results were seen despite higher rates of comorbidities and more challenging anatomy in the patients treated post approval. But "these are short-term outcomes and, ultimately, we’re going to need to know the long-term durability of this type of repair," Dr. Chandu Vemuri said at the annual meeting of the Midwestern Vascular Surgical Society.
The Zenith fenestrated AAA endovascular graft (zFEN) has been commercially available outside the United States since November 2002, and it gained federal approval in April 2012 based on the results of the pivotal U.S. fenestrated trial (USFT). The graft is indicated for the treatment of patients with abdominal aortic or aortoiliac aneurysms that have an infrarenal aortic neck at least 4 mm in length.
Notably, 47% of patients in the current analysis did not meet the USFT anatomic criteria of a 4- to 15-mm infrarenal neck. There were also significantly more mesenteric stents used in this group than in the USFT (13 vs. 0; P < .05), reflecting the higher anatomic complexity of these patients, said Dr. Vemuri, of Washington University, St. Louis.
Compared with the 42 USFT patients, study patients also had significantly higher rates of preoperative coronary artery disease (79% vs. 52%), myocardial infarction (60% vs. 24%), and renal insufficiency (26% vs. 9.5%); all P < .05).
Dr. Vemuri was quick to point out, however, that the results of the study may not broadly translate. The trial was conducted at institutions that had a high aortic volume, and involved highly experienced surgeons, many of whom took part in the USFT and were familiar with the zFEN device.
The technical success rate, with regard to aneurysm exclusion, was 100% in both the study and the USFT. In two study patients, the left renal artery (RA) fenestration was not able to be aligned. One patient had a kinked renal stent that was successfully restented, and one patient was converted to a unibody prosthesis with femoral-femoral bypass and an iliac plug, he said.
Other 30-day outcomes were similar between the study and USFT patients, including mortality (1 vs. 0), renal insufficiency (4 vs. 0), postoperative dialysis (1 vs. 0), and endoleak (10 vs. 9). Two of the 10 endoleaks were type III and 8 were type II.
The most common graft configuration was a scallop of the superior mesenteric artery (SMA) and bilateral RA fenestration in 40 patients, followed by bilateral RA fenestrations alone in 8, and a celiac scallop, SMA fenestration, and bilateral RA fenestration in 3, Dr. Vemuri observed.
One patient each had the following: right RA scallop plus left RA fenestration, right RA fenestration, right accessory RA fenestration, left RA fenestration, celiac scallop and SMA fenestration with a right RA fenestration, and an SMA scallop with left RA fenestration.
Total operative time averaged 250 minutes.
Audience members pressed Dr. Vemuri for details on the 47% of patients who did not meet the USFT anatomic criteria and whether the current cohort was really anatomically challenging or just consisted of on-label cases that were harder than usual.
Dr. Vemuri responded that the intervention was off-label in 27% of patients who did not have the minimum 4-mm infrarenal neck. One graft configuration was more complex than in the device’s instructions for use (IFU) document. All of the patients had a sufficient infrarenal neck for appropriate seal.
"I don’t think the purpose of this study is to endorse use outside the IFU of the device, but to report that when people do, this is what happens," he added.
Dr. Vemuri reported having no financial disclosures. His coauthors reported relationships including serving as consultants or researchers for Cook, which produces the Zenith graft.