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Editorial Comment Reconstructing Diseased Vein Grafts—Great Potential Raises Old Issues David A. Clark, MD Clinical Professor of Medicine Stanford University Stanford, California The deterioration of saphenous vein grafts has long been a discouraging sequela of coronary bypass surgery. Initial failure of a small percentage of bypasses is generally due to technical problems with the anastomoses, or to small caliber, poor run-off recipient vessels. The later deterioration of bypasses with resulting return of myocardial ischemia is generally a combination of intimal hypertro- phy, atherosclerosis, and thrombosis which presents the interven- tional cardiologist faced with an attempt to repair the diseased graft in an effort to avoid a second or third open chest bypass procedure with a technically difficult and dangerous challenge. The use of balloon angioplasty to repair diseased vein bypass grafts was described early and often, and in the early days of percutaneous transluminal coronary angioplasty (PTCA), it was felt that diffusely diseased grafts should be considered a relative contraindication to angioplasty [1]. The anatomically diffuse and friable material that often filled these bypass conduits was felt not to be amenable to the compression techniques of angioplasty in both the short and long term. The danger of distal embolization was enough to discourage even the most fearless interventionalists from performing a dangerous procedure that would probably only delay the inevitable need for repeat surgery as other areas of the graft gradually deteriorated. With the advent of stents, better initial and long-term results were achieved, and with the addition of abcibimax to the intrapro- cedural therapeutic regimen, less distal embolization occurred and better long-term results were achieved. The current report by Dr. Stefanadis and associates [2] builds on their previous experience using autologous coated stents in a variety of situations [3–5]. The article describes the successful reconstruction of a truly diffusely diseased old graft utilizing both conventional stenting and freshly prepared autologous vein and artery coated stents. The coated stent technique is infinitely more complex than conventional stenting but may be significantly better in terms of both initial results and long-term patency of the reconstructed graft. The reported multiple-stenosed, thrombus-filled totally occluded graft would cause even the bravest interventionalist to question the advisability of treating this graft with conventional balloon or stent-assisted angioplasty. The use of distal conventional stents to assure run-off and the placement of autologous vein and artery coated stents to cover the proximal thrombotic region provide an excellent control study of the initial and 6 month angiographic appearance of the reconstructed graft. The superior angiographic appearance of the graft in the coated stent segment as well as the strikingly smaller loss of the initially dilated diameter in the coated (1.4%) vs. the conventional stent segments (34.32%) suggest that, if larger series confirm this superior result, autologous coated stents may be the treatment of the future for diffusely diseased bypass grafts. The problems raised with the technique will probably parallel the skill and logistical problems that faced angiographers and their institutions in the early days of conventional angioplasty. How does an interventionalist become trained to harvest arteries and veins and to sew them onto the stent? Will vascular surgeons be available to do this, or will they be willing to train interventionalists to perform the procedures (see Turf Wars, latest chapter)? Will interventionalists have the surgical skills necessary to learn this new technique, and who will determine if those skills exist? And finally, will the catheterization laboratory be flexible (and sterile) enough to accommodate the prolonged procedural time necessary to perform the task? Hopefully, if this innovative procedure to reconstruct bypass grafts proves to be a superior alternative to repeat open chest bypass surgery, the issues that the new procedure raises will be solved (as the issues raised initially by coronary angioplasty were overcome) to provide the patient with a beneficial, less traumatic method to treat the presence of myocardial ischemia caused by the deterioration of bypass grafts. REFERENCES 1. Clark DA: ‘‘Coronary Angioplasty.’’New York: Wiley-Liss, 1991, pp 69–72. 2. Stefanadis C, Toutouzas K, Tsiamis E, Vlachopoulas C, Kallika- zaros I, Stratos C, Toutouzas P: Total reconstruction of a diseased saphenous vein graft by means of conventional and autologous tissue-coated stents. Cathet Cardiovasc Diagn (in press). 3. Stefanadis C, Toutouzas K, Vlachopoulos C, Tsiamis E, Kallika- zaros I, Stratos C, Vavurankis M, Toutouzas P: Autologous vein graft-coated stent for treatment of coronary artery disease. Cathet Cardiovasc Diagn 38:159–70, 1996. 4. Stefanadis C, Tsiamis E, Vlachopoulos C, Toutouzas K, Stratos C, Kallikazaros I, Vavuranakis M, Toutouzas P: Autologous vein graft-coated stents for the treatment of thrombus-containing coro- nary artery lesions. Cathet Cardiovasc Diagn 40:217–222, 1997. 5. Stefanadis C, Tsiamis E, Vlachopoulos C, Toutouzas K, Stratos C, Kallikazaros I, Giatrakos N, Toutouzas P: Arterial autologous graft-stent for treatment of coronary artery disease: A new tech- nique. Cathet Cardiovasc Diagn 40:302–307, 1997. Catheterization and Cardiovascular Diagnosis 43:322 (1998) r 1998 Wiley-Liss, Inc.

Editorial Comment: Reconstructing diseased vein grafts—great potential raises old issues

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Editorial Comment

Reconstructing Diseased VeinGrafts—Great Potential RaisesOld Issues

David A. Clark, MD

Clinical Professor of MedicineStanford UniversityStanford, California

The deterioration of saphenous vein grafts has long been adiscouraging sequela of coronary bypass surgery. Initial failure of asmall percentage of bypasses is generally due to technical problemswith the anastomoses, or to small caliber, poor run-off recipientvessels. The later deterioration of bypasses with resulting return ofmyocardial ischemia is generally a combination of intimal hypertro-phy, atherosclerosis, and thrombosis which presents the interven-tional cardiologist faced with an attempt to repair the diseased graftin an effort to avoid a second or third open chest bypass procedurewith a technically difficult and dangerous challenge.

The use of balloon angioplasty to repair diseased vein bypassgrafts was described early and often, and in the early days ofpercutaneous transluminal coronary angioplasty (PTCA), it wasfelt that diffusely diseased grafts should be considered a relativecontraindication to angioplasty [1]. The anatomically diffuse andfriable material that often filled these bypass conduits was felt notto be amenable to the compression techniques of angioplasty inboth the short and long term. The danger of distal embolization wasenough to discourage even the most fearless interventionalists fromperforming a dangerous procedure that would probably only delaythe inevitable need for repeat surgery as other areas of the graftgradually deteriorated.

With the advent of stents, better initial and long-term resultswere achieved, and with the addition of abcibimax to the intrapro-cedural therapeutic regimen, less distal embolization occurred andbetter long-term results were achieved.

The current report by Dr. Stefanadis and associates [2] builds ontheir previous experience using autologous coated stents in avariety of situations [3–5]. The article describes the successfulreconstruction of a truly diffusely diseased old graft utilizing bothconventional stenting and freshly prepared autologous vein andartery coated stents. The coated stent technique is infinitely morecomplex than conventional stenting but may be significantly betterin terms of both initial results and long-term patency of thereconstructed graft.

The reported multiple-stenosed, thrombus-filled totally occludedgraft would cause even the bravest interventionalist to question theadvisability of treating this graft with conventional balloon orstent-assisted angioplasty. The use of distal conventional stents to

assure run-off and the placement of autologous vein and arterycoated stents to cover the proximal thrombotic region provide anexcellent control study of the initial and 6 month angiographicappearance of the reconstructed graft. The superior angiographicappearance of the graft in the coated stent segment as well as thestrikingly smaller loss of the initially dilated diameter in the coated(1.4%) vs. the conventional stent segments (34.32%) suggest that,if larger series confirm this superior result, autologous coated stentsmay be the treatment of the future for diffusely diseased bypassgrafts.

The problems raised with the technique will probably parallelthe skill and logistical problems that faced angiographers and theirinstitutions in the early days of conventional angioplasty. How doesan interventionalist become trained to harvest arteries and veinsand to sew them onto the stent? Will vascular surgeons be availableto do this, or will they be willing to train interventionalists toperform the procedures (see Turf Wars, latest chapter)? Willinterventionalists have the surgical skills necessary to learn thisnew technique, and who will determine if those skills exist? Andfinally, will the catheterization laboratory be flexible (and sterile)enough to accommodate the prolonged procedural time necessaryto perform the task?

Hopefully, if this innovative procedure to reconstruct bypassgrafts proves to be a superior alternative to repeat open chestbypass surgery, the issues that the new procedure raises will besolved (as the issues raised initially by coronary angioplasty wereovercome) to provide the patient with a beneficial, less traumaticmethod to treat the presence of myocardial ischemia caused by thedeterioration of bypass grafts.

REFERENCES

1. Clark DA: ‘‘Coronary Angioplasty.’’ New York: Wiley-Liss, 1991,pp 69–72.

2. Stefanadis C, Toutouzas K, Tsiamis E, Vlachopoulas C, Kallika-zaros I, Stratos C, Toutouzas P: Total reconstruction of a diseasedsaphenous vein graft by means of conventional and autologoustissue-coated stents. Cathet Cardiovasc Diagn (in press).

3. Stefanadis C, Toutouzas K, Vlachopoulos C, Tsiamis E, Kallika-zaros I, Stratos C, Vavurankis M, Toutouzas P: Autologous veingraft-coated stent for treatment of coronary artery disease. CathetCardiovasc Diagn 38:159–70, 1996.

4. Stefanadis C, Tsiamis E, Vlachopoulos C, Toutouzas K, Stratos C,Kallikazaros I, Vavuranakis M, Toutouzas P: Autologous veingraft-coated stents for the treatment of thrombus-containing coro-nary artery lesions. Cathet Cardiovasc Diagn 40:217–222, 1997.

5. Stefanadis C, Tsiamis E, Vlachopoulos C, Toutouzas K, Stratos C,Kallikazaros I, Giatrakos N, Toutouzas P: Arterial autologousgraft-stent for treatment of coronary artery disease: A new tech-nique. Cathet Cardiovasc Diagn 40:302–307, 1997.

Catheterization and Cardiovascular Diagnosis 43:322 (1998)

r 1998 Wiley-Liss, Inc.