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Dr Hasan Dosluoglu (Buffalo, NY). In light of the previous paper, it will be interesting to see what percent of your patients were in the high-risk category. So could you please break down those who were physiologically high risk vs those who weren't? What was your mortality in each group? I understand that it was 20% for the entire cohort. Was there a difference between groups and could you identify a subgroup that you, in retrospect, would have preferred not to have done anything?

Dr Thorarinn Kristmundsson. The definition of high risk is a little bit complicated, but that's a definition by the surgeon and the anesthesiologist. Many of these patients have had previous aortic surgery or severe comorbidities and the need for suprarenal clamping was also considered high risk. We haven't done any subgroup analysis to identify risk factors.

Dr Peter Gloviczki (Rochester, Minn). Your group should be congratulated for pushing the envelope and developing this procedure in patients who are really high risk or unfit for surgery repair.

My question is somewhat related to the previous one, because you said that these were all high-risk patients or unfit for surgery. Dr West, from our group, reported in 2006 in the Journal of Vascular Surgery about his 10 year Mayo Clinic experience with 247 patients with a perioperative mortality of 2.8% who had supraceliac clamping and required aortic aneurysm repair because of juxtarenal and suprarenal aneurysms. So there are quite a large number of patients who can undergo open surgery with a very decent mortality.

So I am wondering, when you take all your patients with this anatomy, how many of those did you do open, and how many did you do endo, during this period of time? If you could please give us guidelines on who are the patients suitable for your procedure and if the technology is there to do endovascular repair in good risk patients?

Dr Kristmundsson. During this period of time, we did about 50 patients with an open approach at our clinic. I want to congratulate you on these excellent results that you have at the Mayo Clinic. In our clinic, when we do open surgery with suprarenal clamping of patients that are anatomically unfit for conventional EVAR or infrarenal clamping, we have a mortality of about 10% to 15% in the first 30 days of the procedure. So it's a high risk.

Dr Gloviczki. The operation alone is high risk?

Dr Kristmundsson. Yes.

Dr Timothy Resch. Again, we've published the data from Malmö on our patients. And if you look at standard infrarenal repairs, the results are excellent for the open group with 0% mortality.

But as Dr Kristmundsson pointed out, if you look at the patient cohort included here, and I think that was why we went to this endeavor of doing fenestrated endografts with patients that had physiological high-risk criteria: renal or congestive heart failure, other complicating factors, or the mere risk of having a supraceliac clamp, we were, quite frankly, abhorred with our own experience. We would have liked to send most of our patients to the Mayo Clinic. Unfortunately, it's a fairly long trip. So in light of that, we've used the fenestrated endografts for most of those patients and we think they're doing reasonably well.

Dr Luiz Lanziotti (Rio de Janeiro, Brazil). We've been involved with fenestrated endografts for juxtarenal AAA, as well as branched endografts for thoracoabdominal aneurysm in Rio, and I noticed you had three SMA occlusions. One of the worries we have in our series is regarding visceral ischemia after stenting. Have you identified any possible technical issues that might have caused these occlusions? Regarding clinical outcomes on these patients, how have you identified them and did these patients have previous inferior mesenteric or celiac artery occlusion as well? Did that influence? What are your insights on that?

Dr Kristmundsson. I think that the main problem is that when you place the scallop for the SMA, there is a risk for a rotational misalignment. So you can get a portion of the fabric that lies over the ostia. And that has been reported by other groups as well. So what we do now is we use a liberal use of stents in deep scallops for the SMAs, and we tried to avoid this problem that way.

These patients that had SMA occlusions were asymptomatic, and we found them during routine follow-up at 1 year and 6 months.

Dr Lanziotti. So were any of those stented patients or all three SMA occlusions were scallop-related?

Dr Kristmundsson. All three were from scallops and all three were unstented.

Dr Resch. When we use covered stent, we use Atrium Adventa, and for the renal stents we use the Bridge Assurant, but you can use various kinds of stents.

For the SMA, the issue becomes a little bit trickier, as I'm sure others will mention, because of the sharp angle take-off, especially if you're going for the SMA from below. You'll have a very poor angle of approach and you run a fairly high risk of causing a dissection distally in the SMA when you do the procedure, so whether to use the self-expanding or balloon-expandable stent remains to be proven.

Dr Timothy Chuter (San Francisco, Calif). To clarify the point about selection of high-risk patients. I was fortunate enough to have the opportunity to see the paper on which this presentation was based. One of the things I noted was that 47 patients underwent open repair with suprarenal clamps during the period of this study, which indicates that roughly half the patients who required a suprarenal clamp underwent endovascular procedures and roughly half underwent open surgical procedures. Assuming that the primary triage criterion between open and endovascular treatment was anesthetic risk, the endovascular group truly were high-risk.

This series covered a long period of time and the insertion of a fenestrated stent graft can be a complex operation. I suspect that your skills evolved during that time. Did you notice any difference between early results and late results?

Dr Kristmundsson. During the time of the study, the first year, we only did 1 patient with one fenestration. The cases are getting more and more complicated every year, as we see as the average number of fenestrations in 2007 is 3.1 per patient. In addition, the patients are getting older and sicker. However, we didn't do any subanalysis on the outcomes between the different time periods.