Discussion

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Dr. Mark Farber (Chapel Hill, NC). Dr. Hingorani and his colleagues hypothesize that completion angiography during endovascular aneurysm repair (EVAR) is inadequate in detecting distal external iliac and common femoral artery complications from EVAR. In an effort to determine the true incidence of this complication they incorporated intra-operative duplex to interrogate access artery complications after successful EVAR. Since 2002, they examined 134 patients who underwent EVAR with duplex ultrasound at the completion of the procedure. Additional biplanar imaging was performed in patients whose peak systolic velocities (PSV) was half that of the contra-lateral artery to determine if iliac artery pathology existed. Additionally common femoral artery (CFA) exploration was undertaken when mobile flaps of greater than 3.5 mm were detected. Rigorous duplex follow-up was also performed in the postoperative period.

The authors report that they identified iliac artery complications in 33% of this entire cohort. Among this group, dissections causing severe stenosis of greater than 80% accounted for 77% of these lesions requiring intervention while the remaining 23% were not felt to be hemodynamically significant. Several techniques were employed to repair these injuries including flap excision, tacking sutures, revision, or patch angioplasty. Surprisingly, the authors did not report the use of stents to resolve the inflow issues. The adequacy of repair was confirmed with repeat completion duplex.

Although the duration of follow-up was omitted in the manuscript, the authors report no limb complications associated with this approach during the postoperative period.

Statistical analysis did not demonstrate any associated of injuries with device type, insertion site location, age, or gender. It has been previously reported that access artery diameter is an important determinate in identifying patients developing access artery complication. There was no mention in the analysis section however of CFA or iliac artery diameter or the evaluation of pre-existing disease.

The authors also state that completion angiogram did not reveal any defects because the introducer sheath hindered adequate evaluation. In our experience, routine use of 8 Fr sheaths with floppy wires during completion angiogram accurate detects iliac artery complications. Careful inspection of the common femoral artery with particular attention to any posterior wall plaque prior to repair has essentially eliminated undiagnosed insertion site complications.

I have several questions for the authors:

I would like to thank the society for the privilege of discussing this manuscript and the floor.

Dr. Anil Hingorani. Thank you very much, Dr. Farber, for those insightful questions and I will take them in reverse order. The diameter we thought actually would correlate with which side the larger sheath would be placed and we found that did not correlate at all with what side the larger sheath was being placed probably because we were trying to place the larger sheath on the side that we thought, based on CAT scan, would have a larger artery. Nonetheless, even with the smaller sheath, if you place this in a smaller artery, you can still end up with a problem, so I am not certain that the diameter reduction or the diameter criteria are actually what is going on. I think that it is the relationship between the diameter and the sheath that you are placing in as much. I am not sure that assessing the diameter in as much as the data we have thus far suggests that it is not questionably native disease or the diameter, but rather the damage that the sheath does to the artery. In terms of defining our hemodynamic significant, usually we have a volume flow of less than 100cc, but the ratio is 2.5 lesion in the distal artery, we become quite concerned that there is a hemodynamic problem. We did have stents placed in after two patients who had iliac artery lesions that were detected by completion duplex, so yes, we did place stents. Twenty-five percent of the cases were changed by duplex imaging, 13% of the arteries had some type of intervention based on the completion duplex, which is actually consistent with the 2007 data from the European Journal of Surgery from France and Moldenato's series where 13% of the patients had problems with late limb complications after EVAR from NYU in 2004 in the Journal of Vascular Surgery. So, while we may have different terminology, our results in terms of the number of arteries that actually filmed are actually similar.