J Thorac Cardiovasc Surg 2008;135:463
© 2008 The American Association for Thoracic Surgery
Optimal target vessel stenosis for radial artery grafting
Robert H. Habib, PhD
Cardiovascular and Pulmonary Research, Yvonne Viens, SGM, Research Institute, St Vincent Mercy Medical Center, Toledo, Ohio
Department of Surgery, University of Toledo College of Medicine, Toledo, Ohio
To the Editor:
The article by Bleiziffer and colleagues1
is the latest in a growing body of literature2-6 reporting worse radial artery graft patency when anastomosed to coronary targets with moderate disease (eg, 70%–90% stenosis) compared with targets with severe stenosis (>90% stenosis). This finding is highly reproducible, as evidenced by analyses of both retrospectively2-5 and prospectively1,6 collected angiographic data reported by multiple authors at multiple institutions spanning multiple continents. Arguably, the convergence of the published literature to the same target stenosis–radial patency relationship coupled with the available objective mechanistic explanation (competitive flow) for this finding should put this question to rest. More specifically, when one is faced with the choice, radial artery grafts should be preferentially anastomosed to the most severely diseased coronary targets (>90% stenosis). These studies, however, have not objectively addressed the question of which conduit type (vein vs radial) should be used for coronary targets with less severe disease (eg, <90% stenosis). Yet, in their article, Bleiziffer and coworkers concluded the following: "On the basis of our results, we attempt to use the radial artery only for target coronary arteries with 90% or greater stenosis." I contend that the graft patency data presented to date by these authors and others2-6 do not justify such a limitation on radial artery grafting, and that such a position represents a case of over-concluding. More specifically, some (perhaps including the authors1) may extrapolate this conclusion, which is based only on data for radial artery patency, to suggest that saphenous vein grafts would then be superior to radial artery grafts when placed in coronary targets with less than 90% disease. I am unaware of any such data. To the contrary, in their most recent report, Desai and colleagues7 analyzed prospectively collected radial and vein graft patency data and reported the following: 1) Radial patency increases with increased target stenosis; 2) vein patency does not vary with target stenosis; and, most important, 3) radial patency is superior to that of vein patency when placed in both moderately and severely diseased coronary targets. These data indicate that the radial artery should be preferred to the vein even for moderately diseased coronary targets, a conclusion that contradicts the authors' recommendation in this article.1
References
- Bleiziffer S, Hettich I, Eisenhauer B, Ruzicka D, Wottke M, Hausleiter J, et al. Patency rates of endoscopically harvested radial arteries one year after coronary artery bypass grafting. J Thorac Cardiovasc Surg 2007;134:649-656.[Abstract/Free Full Text]
- Royse AG, Royse CF, Tatoulis J, Grigg LE, Shah P, Hunt D, et al. Postoperative radial artery angiography for coronary artery bypass surgery. Eur J Cardiothorac Surg 2000;17:294-304.[Abstract/Free Full Text]
- Maniar HS, Sundt TM, Barner HB, Prasad SM, Peterson L, Absi T, et al. Effect of target stenosis and location on radial artery graft patency. J Thorac Cardiovasc Surg 2002;123:45-52.[Abstract/Free Full Text]
- Maniar HS, Barner HB, Bailey MS, Prasad SM, Moon MR, Pasque MK, et al. Radial artery patency: are aortocoronary conduits superior to composite grafting?. Ann Thorac Surg 2003;76:1498-1504.[Abstract/Free Full Text]
- Desai ND, Cohen EA, Naylor CD, Fremes SE. A randomized comparison of radial-artery and saphenous-vein coronary bypass grafts. N Engl J Med 2004;351:2302-2309.[Medline]
- Lemma M, Mangini A, Gelpi G, Innorta A, Spina A, Antona C. Is it better to use the radial artery as a composite graft? Clinical and angiographic results of aorto-coronary versus Y-graft. Eur J Cardiothorac Surg 2004;26:110-117.[Abstract/Free Full Text]
- Desai ND, Naylor CD, Kiss A, Cohen EA, Feder-Elituv R, Miwa S, et al. Impact of patient and target-vessel characteristics on arterial and venous bypass graft patency: insight from a randomized trial. Circulation 2007;115:684-691.[Abstract/Free Full Text]
