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Traditional Vein Harvest Yields the Best Graft Patency Rate
CORRESPONDENCE
We read with interest the article by Ouzounian and colleagues [1] about the effect of endoscopic vs open saphenous vein harvest techniques on outcomes after coronary artery bypass grafting. Several studies [2] have focused on the reduction of wound infection and the cosmetic effect of endoscopic vein harvest. Ouzounian and colleagues concluded in their observational report that endoscopic saphenous vein harvest is associated with a lower rate of leg infection and reduced readmission to the hospital for acute coronary syndromes. The lack of histopathologic and angiographic data is the main limitation to this excellent report. Other contradicting reports by Rousou [3] and Lopes [4] and their colleagues showed saphenous vein endothelial injury and decreased graft patency rate after endoscopic vein harvest. Lopes and colleagues [4] also reported higher rates of death, myocardial infarction, and repeat revascularization at 3 years. Endoscopic harvesting requires extra training and higher cost in addition to carbon dioxide embolic risk [5]. Several harvesting techniques have evolved during the last decade, including laryngoscopic and skin bridging. All share the same deleterious technical element of excessive traction and tension causing the well-documented detrimental effect on saphenous vein endothelium and consequently affecting the graft patency rate, which is the most important issue in our daily coronary bypass grafting procedures. Time has proven that the best graft patency rate is achieved by conventional vein harvesting techniques because minimal traction is exerted during the dissection. Complications in the lower extremity, such as cellulitis and wound infection, hematoma, seroma, edema, and saphenous neuropathy and neuralgia, are less common using the endoscopic vein harvest compared with the open technique. Most of these complications are avoidable when we respect this procedure. Saphenous vein harvesting is a clean surgery, so why do we get too many infections? The concept that the vein harvesting is performed by the most junior member of the team has to be changed. Perfection of technical skills of careful and clean dissection, proper hemostasis, avoiding excessive diathermy, and gentle handling of skin and tissues during closure must be emphasized and practiced in every case. Leg compression and proper bandaging using occlusive wrap dressings for several days with leg elevation are equally important, especially in high-risk groups. Wound closure results are best achieved either before heparinization or after its neutralization with protamine. Fine details of this procedure must be addressed and dealt with. Only experienced residents or physician assistants are privileged to perform harvesting and closure. Khaled Al-Ebrahim, FRCSC Department of Cardiac Surgery University Hospital PO Box 80215 Jeddah, 21589 Saudi Arabia e-mail: [email protected] Abdelrahman M. Abdelrahman, MD Department of Cardiothoracic Surgery Alazhar University Hospital Cairo, Egypt © 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
References 1. Ouzounian M, Hassan A, Buth K, et al. Impact of endoscopic versus open saphenous vein harvest techniques on outcomes after coronary artery bypass grafting. Ann Thorac Surg 2010; 89:403– 8. 2. Marker S, Kutty R, Edmonds L, Sadat U, Nair S. A meta analysis of minimally invasive versus traditional vein harvest technique for coronary artery bypass surgery. Interact CardioVasc Thorac Surg 2010;10:266 –70. 3. Rousou LJ, Taylor KB, Lu XG, et al. Saphenous vein conduits harvested by endoscopic technique exhibit structural and functional damage. Ann Thorac Surg 2009;87:62–70. 4. Lopes R, Hafley G, Allen KB, et al. Endoscopic versus open vein-graft harvesting in coronary-artery bypass surgery. N Engl J Med 2009;361:235– 44. 5. Lin TY, Chiu KM, Wang MJ, Chu SH. Carbon dioxide embolism during endoscopic saphenous vein harvesting in coronary artery bypass surgery. J Thorac Cardiovasc Surg 2003;126:2011–5.
Reply To the Editor: We thank Drs Al-Ebrahim and Abdelrahman [1] for their comments on our article examining outcomes after endoscopic vs traditional saphenous vein harvesting for coronary artery bypass grafting [2]. We certainly agree with the authors that attention to sterile technique, careful hemostasis, and gentle dissection are critical elements to successful open vein harvesting. Indeed, we believe that these principles should be applied to all surgical procedures, regardless of degree of invasiveness. We also agree that vein harvesting should be performed, or at least closely supervised, by an experienced physician or surgical assistant. Despite the value of these general surgical principles, we respectfully disagree with the authors’ anecdotal assertion that “most (wound-related) complications are avoidable when we respect this procedure.” The data regarding improved wound outcomes after endoscopic vein harvesting are clear. A metaanalysis of 11 randomized trials found that endoscopic vein harvesting was associated with a reduction in the incidence of wound infections with an impressive odds ratio of 0.22 (95% confidence interval [CI], 0.14 to 0.37, p ⬍ 0.00001) [3]. This results in a number needed to treat of 14, comparable to some of the most effective interventions in medicine. In contrast to the robust data regarding wound-related outcomes, there are little data examining graft patency and clinical outcomes after the two harvesting techniques. Our study found no negative association between endoscopic harvesting and short-term (odds ratio, 0.95; 95% CI, 0.80 to 1.13) or midterm (hazard ratio, 0.93; 95% CI, 0.83 to 1.05) adverse outcomes [2]. In contrast, Lopes and colleagues [4] found that endoscopic vein harvesting was associated with higher rates of death, myocardial infarction, and repeat revascularization at 3 years (hazard ratio, 1.22; 95% CI, 1.01 to 1.47; p ⫽ 0.04). Each study had its own strengths and weaknesses, and as Athanasiou points out in the accompanying editorial to our article [5], the validity of research findings increases as data accumulate, and the actual effect size may be between the two reported. The clinical equipoise stemming from these conflicting results highlights the need for a randomized clinical trial with long-term follow-up of clinical outcomes to directly compare endoscopic vs open saphenous Ann Thorac Surg 2010;90:1059 – 63 • 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.02.090
MISCELLANEOUS
Traditional Vein Harvest Yields the Best Graft Patency Rate To the Editor:
We read with interest the article by Ouzounian and colleagues [1] about the effect of endoscopic vs open saphenous vein harvest techniques on outcomes after coronary artery bypass grafting. Several studies [2] have focused on the reduction of wound infection and the cosmetic effect of endoscopic vein harvest. Ouzounian and colleagues concluded in their observational report that endoscopic saphenous vein harvest is associated with a lower rate of leg infection and reduced readmission to the hospital for acute coronary syndromes. The lack of histopathologic and angiographic data is the main limitation to this excellent report. Other contradicting reports by Rousou [3] and Lopes [4] and their colleagues showed saphenous vein endothelial injury and decreased graft patency rate after endoscopic vein harvest. Lopes and colleagues [4] also reported higher rates of death, myocardial infarction, and repeat revascularization at 3 years. Endoscopic harvesting requires extra training and higher cost in addition to carbon dioxide embolic risk [5]. Several harvesting techniques have evolved during the last decade, including laryngoscopic and skin bridging. All share the same deleterious technical element of excessive traction and tension causing the well-documented detrimental effect on saphenous vein endothelium and consequently affecting the graft patency rate, which is the most important issue in our daily coronary bypass grafting procedures. Time has proven that the best graft patency rate is achieved by conventional vein harvesting techniques because minimal traction is exerted during the dissection. Complications in the lower extremity, such as cellulitis and wound infection, hematoma, seroma, edema, and saphenous neuropathy and neuralgia, are less common using the endoscopic vein harvest compared with the open technique. Most of these complications are avoidable when we respect this procedure. Saphenous vein harvesting is a clean surgery, so why do we get too many infections? The concept that the vein harvesting is performed by the most junior member of the team has to be changed. Perfection of technical skills of careful and clean dissection, proper hemostasis, avoiding excessive diathermy, and gentle handling of skin and tissues during closure must be emphasized and practiced in every case. Leg compression and proper bandaging using occlusive wrap dressings for several days with leg elevation are equally important, especially in high-risk groups. Wound closure results are best achieved either before heparinization or after its neutralization with protamine. Fine details of this procedure must be addressed and dealt with. Only experienced residents or physician assistants are privileged to perform harvesting and closure. Khaled Al-Ebrahim, FRCSC Department of Cardiac Surgery University Hospital PO Box 80215 Jeddah, 21589 Saudi Arabia e-mail: [email protected] Abdelrahman M. Abdelrahman, MD Department of Cardiothoracic Surgery Alazhar University Hospital Cairo, Egypt © 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
References 1. Ouzounian M, Hassan A, Buth K, et al. Impact of endoscopic versus open saphenous vein harvest techniques on outcomes after coronary artery bypass grafting. Ann Thorac Surg 2010; 89:403– 8. 2. Marker S, Kutty R, Edmonds L, Sadat U, Nair S. A meta analysis of minimally invasive versus traditional vein harvest technique for coronary artery bypass surgery. Interact CardioVasc Thorac Surg 2010;10:266 –70. 3. Rousou LJ, Taylor KB, Lu XG, et al. Saphenous vein conduits harvested by endoscopic technique exhibit structural and functional damage. Ann Thorac Surg 2009;87:62–70. 4. Lopes R, Hafley G, Allen KB, et al. Endoscopic versus open vein-graft harvesting in coronary-artery bypass surgery. N Engl J Med 2009;361:235– 44. 5. Lin TY, Chiu KM, Wang MJ, Chu SH. Carbon dioxide embolism during endoscopic saphenous vein harvesting in coronary artery bypass surgery. J Thorac Cardiovasc Surg 2003;126:2011–5.
Reply To the Editor: We thank Drs Al-Ebrahim and Abdelrahman [1] for their comments on our article examining outcomes after endoscopic vs traditional saphenous vein harvesting for coronary artery bypass grafting [2]. We certainly agree with the authors that attention to sterile technique, careful hemostasis, and gentle dissection are critical elements to successful open vein harvesting. Indeed, we believe that these principles should be applied to all surgical procedures, regardless of degree of invasiveness. We also agree that vein harvesting should be performed, or at least closely supervised, by an experienced physician or surgical assistant. Despite the value of these general surgical principles, we respectfully disagree with the authors’ anecdotal assertion that “most (wound-related) complications are avoidable when we respect this procedure.” The data regarding improved wound outcomes after endoscopic vein harvesting are clear. A metaanalysis of 11 randomized trials found that endoscopic vein harvesting was associated with a reduction in the incidence of wound infections with an impressive odds ratio of 0.22 (95% confidence interval [CI], 0.14 to 0.37, p ⬍ 0.00001) [3]. This results in a number needed to treat of 14, comparable to some of the most effective interventions in medicine. In contrast to the robust data regarding wound-related outcomes, there are little data examining graft patency and clinical outcomes after the two harvesting techniques. Our study found no negative association between endoscopic harvesting and short-term (odds ratio, 0.95; 95% CI, 0.80 to 1.13) or midterm (hazard ratio, 0.93; 95% CI, 0.83 to 1.05) adverse outcomes [2]. In contrast, Lopes and colleagues [4] found that endoscopic vein harvesting was associated with higher rates of death, myocardial infarction, and repeat revascularization at 3 years (hazard ratio, 1.22; 95% CI, 1.01 to 1.47; p ⫽ 0.04). Each study had its own strengths and weaknesses, and as Athanasiou points out in the accompanying editorial to our article [5], the validity of research findings increases as data accumulate, and the actual effect size may be between the two reported. The clinical equipoise stemming from these conflicting results highlights the need for a randomized clinical trial with long-term follow-up of clinical outcomes to directly compare endoscopic vs open saphenous Ann Thorac Surg 2010;90:1059 – 63 • 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.02.090
MISCELLANEOUS
Traditional Vein Harvest Yields the Best Graft Patency Rate To the Editor: