Response to Letter to Editor

Abstract

We would like to thank Dr Chaudhuri for his in-depth response on our recent publication “Dacron or ePTFE for femoro-popliteal above-knee bypass grafting: short and long-term results of a multicentre randomised trial.” Eur J Vasc Endovasc Surg 2009; 37: 457–463. Indeed it was mentioned that the patency rates with large-caliber prosthetic grafts in the fem-distal position (8 mm instead of 6 mm) were maybe better.1Abbott W.M. Green R.M. Matsumoto T. Wheeler J.R. Miller N. Veith F.J. et al.Prosthetic above-knee femoropopliteal bypass grafting: results of a multicenter randomized prospective trial. Above-Knee Femoropopliteal Study Group.J Vasc Surg. 1997 Jan; 25: 19-28Google Scholar, 2Green R.M. Abbott W.M. Matsumoto T. Wheeler J.R. Miller N. Veith F.J. et al.Prosthetic above-knee femoropopliteal bypass grafting: five-year results of a randomized trial.J Vasc Surg. 2000 Mar; 31: 417-425Google Scholar Unfortunately all these studies were flawed by nonrandomised design and potential selection bias. There is no level 1 evidence which clearly showed the better results of 8 mm prostheses in the femoro-distal position. We agree that new graft technologies might give better results compared to both, the standard Dacron and ePTFE, we used in our study. The older vascular surgeons remembered the “strong expert opinion” that patency rates with PTFE femoro-popliteal bypass above and below the knee were equal to or better than those with the same operation performed with saphenous vein.3Veith F.J. Moss C.M. Fell S.C. Rhodes B.A. Somberg E. Weiss P. et al.Expanded polytetrafluorethylene grafts in reconstructive arterial surgery. Preliminary report of the first 110 consecutive cases for limb salvage.JAMA. 1978 Oct 20; 240: 1867-1869Google Scholar This “evidence” was the background of our prospective RCT which clearly showed the opposite of the opinion of the experts in the 80th. Our group was also involved in the prospective non-consecutive cohort study of the Gore–Tex Propaten Vascular Graft in the femoro-distal position. The design of this study lodged all the potential risks of bias.4Gurusamy K.S. Gluud C. Nikolova D. Davidson B.R. Assessment of risk of bias in randomised clinical trials in surgery.Br J Surg. 2009; 96: 342-349Google Scholar The primary patency result of 91% of the Gore Propaten resembles our 1-year patency result of Dacron.5Walluscheck K.P. Bierkandt S. Brandt M. Cremer J. Infrainguinal ePTFE vascular graft with bioactive surface heparin bonding. First clinical results.J Cardiovasc Surg (Torino). 2005; 46: 425-430Google Scholar The two-year primary patency was also comparable with our Dacron result.6Peeters P. Verbist J. Deloose K. Bosiers M. Results with heparin bonded polytetrafluoroethylene grafts for femorodistal bypasses.J Cardiovasc Surg (Torino). 2006 Aug; 47: 407-413Google Scholar We agree with Dr Chaudhuri that we should not ignore possible renewals of allograft materials but he should also agree with us that we should learn from the past. Only proper designed RCTs without a mix of above-knee and below-knee bypass grafts could prove that heparin bounding ePTFE grafts should become the first choice allograft material in the femoro-distal position. Lacking this evidence so far we still conclude that Dacron is the preferential graft material in the above-knee fem-pop position if a suitable saphenous vein is absent. Re: Dacron or ePTFE for Femoro-popliteal Above-Knee Bypass Grafting: Short- and Long-term Results of a Multicentre Randomised Trial, van Det et al. in Eur J Vasc Endovasc Surg (2009) 37, 457–463European Journal of Vascular and Endovascular SurgeryVol. 38Issue 2PreviewI read with interest the paper by the above authors that challenges the more conventional use of ePTFE for prosthetic above-knee femoropopliteal bypasses. A few issues arise: firstly, the use of grafts of 6 mm diameter when an 8 mm graft is an option, which is not an unconventional one. The authors have also ignored the issue of heparin-bonded ePTFE grafts such as the Gore Propaten vascular graft in the discussion, which has demonstrated 84% and 91% 1-year primary patency rates,1,2 which is also supported on a haematological basis. Full-Text PDF Open Archive