Saphenous vein bypass grafts

Antiplatelet therapy reduces the risk of occlusion of saphenous grafts, and a low dose of aspirin (325 mg/d) is as effective as a higher dose (975 mg/d) or the combination of aspirin and dipyridamole. Rates of occlusion are similar for aspirin begun before or 6 h after surgery, but the incidence of hemorrhage is increased with preoperative administration. 

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The accumulation of apo(a) in the aorta wall and in saphenous vein bypass grafts in relation to Lp(a) levels was recently demonstrated (C14, R3). Subsequently, the preferential deposition of extracellular apo(a) in atherosclerotic lesions of aortic and coronary artery tissue, in conjunction with the intracellular localization of apo(a) in macrophage-derived foam cells, has been the focus of a number of studies (N6, P7, S34, S35, W17). These careful studies also demonstrated the avid binding of Lp(a) to extracellular matrix components and the colocalization of fibrin and apo(a) in atheromatous lesions (N8, W16). 

Waksman R, Ajani AE, White RL, et al, Intravascular gamma radiation for in-stent restenosis in saphenous-vein bypass grafts. N Engl J Med 2002 346 1194-11 99. 

Based on four randomized, double-blind trials aspirin is clearly effective in unstable angina (45-48). It reduces the risk of MI and cardiac death by 50 to 70% either alone or in concert with the anticoagulant heparin. Aspirin also has a role in reducing the incidence of early closure of saphenous vein bypass grafts of the coronary arteries and following coronary artery angioplasty (49-58). 

Saphenous Vein Bypass Graft Disease, edited by Eric R. Bates and David R. Holmes, Jr. 

N.B., Goormastic, M., Cosgrove, D.M., Vein graft disease the clinical impact of stenoses in saphenous vein bypass grafts to coronary arteries. J. Thorac. Cardiovasc. 

Campeau L, Enjalbert M, Lesperance J, et al. The relation of risk factors to the development of atherosclerosis in saphenous vein bypass grafts and the progression of disease in the native circulation a study 10 years after aortocoronary bypass surgery. N Engl J Med 1984 311 1329-32. 

Johnson WC, Lee KK, et al. A comparative evaluation of polytetrafluoroethylene, umbilical vein, and saphenous vein bypass grafts for femoral-popliteal above-knee revascularization a prospective randomized Department of Veterans Affairs cooperative study. J Vase Surg 2000 32 268-77. 

Fig. 19.2a-c. A 62-year-old man after coronary artery revascularization using two saphenous vein bypass grafts. MDCT clearly demonstrates the direct retrosternal course of a patent bypass vessel (arrow). The second bypass is occluded (arrowhead)... 

Bush HL Jr., Nadseth DC, Curl GR. In situ saphenous vein bypass grafts for limb salvage. Am 7 S rg 1985 148 477-480. 

A broad-based cardiomyoplasty market should emerge by the late 1990s. Successhil development of a small-diameter graft to use in coronary bypass surgery instead of the patient s saphenous vein or mammary artery seems likely to occur by the year 2000. Development of appropriate materials and manufacturing methods are needed to maintain patency without damaging blood in grafts below 4 mm in diameter. 

Coronary artery bypass graft surgery Thoracic surgery whereby parts of a saphenous vein from a leg or internal mammary artery from the arm are placed as conduits to restore blood flow between the aorta and one or more coronary arteries to bypass the coronary artery stenosis (occlusion). 

Goldman S, Copeland J, Moritz T, Hendo-sonW, Zadina K, Ovitt T, Doherty J, ReadR, ChederE. Sako Y Improvement in early saphenous vein graft patency after coronary artery bypass surgery with antiplatelet therapy Results of a Veterans Admin-istration Cooperative Study. Circulation 22 1324,1988... 

D. S. Baim, D. Wahr, B. George, M. B. Leon, J. Greenberg, D. E. Cutlip, U. Kaya, J. J. Popma, K. K. L. Ho and R. E. Kuntz, Randomized trial of a distal embolic protection device during percutaneous intervention of saphenous vein aorto-coronary bypass grafts, Circulation 105, 1285-1290 (2002). 

G. W. Stone, C. Rogers, J. Hermiller, R. Feldman, P. Hall, R. Haber, A. Masud, P. Cambier, R. P. Caputo, M. Turco, R. Kovach, B. Brodie, H. C. Herrmann, R. E. Kuntz, J. J. Popma, S. Ramec and D. A. Cox, Randomized comparison of distal protection with a filter-based catheter and a balloon occlusion and aspiration system during percutaneous intervention of diseased saphenous vein aorto-coronary bypass grafts, Circulation 108, 548-553 (2003). 

Following the introduction of saphenous vein graft replacement for the severely occluded coronary arteries by Favorolo and Garrett in 1967, coronary artery bypass grafting (CABG) became an accepted and commonly used approach for the management of IHD. The... 

Reversed segments of autologous saphenous vein can be used as appropriate conduits. Particularly in coronary revascularization, the internal mammary arteries and the radial arteries have widely been used [3]. However, autologous vessels may be insufficient for multiple or repeated bypasses and/or saphenous veins may have varicose degenerative alterations. Therefore, allograft arteries and veins as well as synthetic tubes have been developed, but they proved to be less satisfactory as conduits [4, 5] particularly, synthetic grafts with an internal diameter of 6 mm or less are prone to thrombus induction and occlusion [6]. 

Autograft Graft transplanted firom part of a patient s body to another Example saphenous vein graft for peripheral bypass... 

Desai ND, Cohen EA, Naylor CD, et al. A randomized comparison of radial-artery and saphenous vein coronary bypass grafts. NEngl J Med 2004 351 2302-9. 

Goldman S, Zadina K, Moritz T, et al. Long-term patency of saphenous vein and left internal mammary artery grafts after coronary artery bypass surgery results from a Department of Veterans Affairs cooperative study. J Am Coll Cardiol 2004 44 2149-56. 

Fig. 21.10a,b. CTA of coronary bypass grafts, a Cross-sectional image of a patent saphenous vein graft (arrows) exhibiting severe calcified wall changes. Data of another patient (b) who presented with acute chest pain shows two venous grafts, with thrombus formation (small arrows) and total occlusion of one graft (arrowhead)... 

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