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Dr Peter Gloviczki (Rochester, Minn). I enjoyed your paper very much and would like to congratulate you on an in-depth analysis of data of mortality at 1 year. You mentioned that you included 49 surgeons of 11 centers, and what I wanted to hear is if your data depended on surgeon's expertise. What has happened is that more recently we do less open repairs in more complex patients. We do more suprarenal or supraceliac clamping because most of the usual bread-and-butter infrarenal aneurysms are repaired endovascularly. So I am wondering if surgeon's experience is important or not in the outcome.

When we looked recently at results of 126 juxtarenal aneurysms, we found that the level of aortic clamp replacement (supravisceral vs suprarenal: supravisceral vs inter-renal) had no significant effect on the development of cardiac, pulmonary, or renal complications nor on mortality. I am wondering if you found a difference or whether you had enough patients who had supraceliac clamping who maybe had a higher mortality.

Otherwise your 1-year outcome data are very similar to ours, we had a 6% mortality by 1 year after juxtarenal aneurysm repair and a 0.8% mortality at 30 days, which is very similar to our results with infrarenal aortic aneurysm.

Dr Adam W. Beck. Although we have the capability of looking at surgeon effect, we did not do so for this particular study. I saw your publication regarding juxtarenal aneurysms. We included all patients who had an aortic clamp above both renal arteries, but we did not differentiate suprarenal vs supraceliac. If we looked at just a clamp above one renal artery, those patients had a similar outcome to the infrarenal clamp group in our database.

Dr Jack Cronenwett. When we look at these data, we find some apparent impact of surgeon volume, but the numbers become very small and impossible to accurately analyze yet in multivariate analysis. We are using the registry primarily for quality improvement efforts. But overall, the 30-day mortality results in both the open and endovascular groups were quite excellent.

Dr Tara Mastracci (Cleveland, Ohio). Thank you for your very thoughtful analysis. This is an area of interest for us at the Cleveland Clinic as well. I was wondering about your choice of a 1-year endpoint. In an era where we are now achieving very acceptable perioperative outcomes for endovascular repair even in high-risk patients who have multiple comorbidities threatening their longevity, should we be focusing on long-term outcomes, instead of 1-year mortality, to better inform the decision to operate on only the high-risk patients in whom we can actually prolong survival?

Dr Beck. This is an important point. If you look at most published risk prediction models for AAA surgery, they look primarily at perioperative mortality. There are also a number of publications that have identified independent risk factors for mortality at 3 and 5 years, but no risk prediction models. Further, many other factors such as subsequent cancer or heart disease affect 5-year mortality. We chose the 1-year time point because it corresponds well with 1-year rupture risk, which is often discussed with patients during decision making.

Dr John Hallett (Charleston, SC). This is really an important study because the methodology that you are using for vascular has been used to improve cardiac care in your region of the country. And, I am interested in how you are going to use this information now with the surgeons to improve care. Are you going to use this methodology in a prospective way so the surgeon can advise the patient? Are you going to use it to advise the surgeon in decision-making? How are you going to use these data in quality improvement that has been used so well for cardiac surgery?

Dr Beck. We presented these data at the recent meeting of the Vascular Study Group and it was believed to be important for future clinical decision making. To facilitate this, it was decided to make small pocket cards so VSGNNE members could easily remember these risk factors.

Dr Maciej Dryjski (Buffalo, NY). What is striking for me is that congestive heart failure (CHF) is a predictive factor for mortality in the endovascular group but not in the open group. It seems to me that we perhaps do something different when we treat endovascularly a patient with an aneurysm. The question is if the dye given in perioperative evaluation, during the operation, and then on the follow-up CTs, has an influence on 1-year postoperative mortality?

Dr Beck. We did look at the amount of contrast that patients received during EVAR in this study. We were trying to look at preoperative data so that it could help the surgeon and the patient make decisions before the operation. But in other analyses, we have not found that contrast volume affected mortality after EVAR.

There were more patients in the EVAR group that had CHF by percentile, and there were more patients that had more severe CHF in the EVAR group. This may be why CHF was an independent predictor of outcome in the EVAR patients and not in the open repair patients.

Dr Jerry Goldstone (Cleveland, Ohio). One of the issues that you did not discuss was gender differences. Were there any differences male vs female, and in particular, aneurysm size? There has been some suggestion that women's aneurysms may rupture at a smaller size and, therefore, the threshold for operating might be lower than what we.

Dr Beck. We did look at gender. There was no difference in outcomes between men and women, although your point is well taken about aneurysm size and rupture risk. Certainly we cannot prescribe fixed diameter thresholds for elective repair. However, for patients with three to four identified risk factors for mortality after open repair, it would appear that repair should be delayed until a larger diameter is reached. On a patient-by-patient basis, you definitely would have to consider gender in setting the optimal diameter threshold for elective repair.