Discussion

Dr Gregory Pearl (Dallas, Tex). In your initial diagram you showed a nice configuration of two superficial femoral veins with an anastomosis between those two segments. Did you have any patients that required more than two segments sewn together? Did that impact your outcomes at all?

Dr Adam W. Beck (Dallas, Tex). Yes, I believe so. There were a few patients that had to have patched together vein grafts, but none of those patients have developed stenoses.

Dr John Ricotta (Stony Brook, NY). I have three questions for you.

First, could you tell us what the sites of recurrence were? Were they at anastomotic sites, sites of vein valves?

Second, in your last slides it seemed to me that if you did not have coronary disease, you still did quite well even with a small vein. And given that, what are your feelings about vein size?

And last, in your definition of smoking, was that any history of smoking or was it persistent smoking after the procedure was done?

Dr Beck. I will answer your last question first. The smoking was nearly 100% prevalent in this population. We did look at persistent smoking after the NAIS, and it was not statistically significant. The P value of stenosis in persistent smokers was 0.12 versus patients that quit smoking after NAIS. The relative risk increase for every 10 pack year history of smoking is 0.27, so there is a 27% increase in relative risk.

Regarding where the lesions were in the NAIS graft, they were distributed everywhere. We had one that was immediately at an anastomotic site. Most of them were either close to the anastomosis or in the mid graft.

I think you bring up a very good point that even though we dichotomized the patients into above or below 7.2 mm, in point of fact, there are a large number of patients that had grafts less than 7.2 mm in diameter who have done fine and have not had any stenoses to date. Because of this, we do not use size less than 7 mm as a contraindication for this procedure.