HHS Public Access Author manuscript Author Manuscript
Am Surg. Author manuscript; available in PMC 2016 July 01. Published in final edited form as: Am Surg. 2015 July ; 81(7): E274–E276.
An Optimized Preparation Technique for Saphenous Vein Graft Eric S. Wise, MD1,ƚ, Kyle M. Hocking, PhD1,2, Daniel Feldman, BA1, Padmini Komalavilas, PhD1,3, Joyce Cheung-Flynn, PhD1, and Colleen M. Brophy, MD1,3 1Department
of Surgery, Vanderbilt University, Nashville TN, USA
2Department
of Biomedical Engineering, Vanderbilt University, Nashville TN, USA
Author Manuscript
3VA
Tennessee Valley Healthcare System, Department of Surgery, Division of Vascular Surgery, Nashville TN, USA
Author Manuscript
Human saphenous vein (HSV) remains the most widely used conduit for peripheral and coronary bypass procedures. However, data from the Project of Ex-Vivo vein graft Engineering via Transfection-III (PREVENT III) trial revealed vein graft failure rates of HSV as high as 40% at one year postoperatively.(1) While early vein graft failure (3,000 patients who underwent coronary artery bypass grafting) was stratified by type of preservation solution, including normal saline, buffered salt solutions or autologous whole blood. Controlling for baseline demographics and operative characteristics, those patients for whom a buffered salt solution (e.g. Plasma-Lyte A, University of Wisconsin solution) was used for graft preservation had a significant improvement in vein graft failure at one year, and trended toward a significant benefit at five years. Balanced salt solutions, designed considering physiologic pH and electrolyte composition, better preserved the HSV graft and reduced vein graft failure.(4) HSV graft is still frequently preserved in normal saline solution prior to implantation. Normal saline, while inexpensive and readily available, is acidic, with a pH < 6.0, mildly hyperosmolar and lacks cellular nutrients or antioxidants that may benefit the
Am Surg. Author manuscript; available in PMC 2016 July 01.
Wise et al.
Page 3
Author Manuscript
conduit. Therefore, the final component of the optimized preparation technique is the use of a balanced, pH-buffered salt solution such as Plasma-Lyte A as the preservation medium, to optimally preserve the graft, particularly the sensitive endothelial monolayer critical to maintenance of graft patency. Components of the OP bundled as a kit are illustrated in Figure 1. A brief demonstration of the OP is available as an mpeg-4 download at https://redcap.vanderbilt.edu/surveys/? s=HWC8NLAXLK, or for streaming at https://www.youtube.com/watch?v=OKogkvaiQ7I.
Author Manuscript
Vein graft preparation represents a unique window of opportunity in which conduit function can be augmented, potentially leading to enhanced vein graft patency. Recognizing an unmet clinical need, an optimized technique has been engineered to prepare HSV graft prior to implantation into the aortocoronary or peripheral circulation. The technique is effective at identifying leaks, maintaining graft orientation and dilating the conduit while requiring only simple modifications from current practice. In vivo studies are currently underway to determine whether there is concomitant improvement in intimal hyperplasia, using a porcine carotid interposition model.
Acknowledgments Grant Support Acknowledgment: This study was supported in part by resources and materials from the Veterans Affairs Tennessee Valley Healthcare System and by a Biomedical Laboratory Research and Development grant from the Department of Veterans Affairs to Dr Brophy. Dr Brophy was supported by grant R01HL70715-09 from the National Institutes of Health. Dr Cheung-Flynn was supported by grant R01HL105731-01A1 from the National Institutes of Health. Vanderbilt RedCAP is supported by the CTSA Award UL1 TR000445 from NCATS/NIH
Author Manuscript
Drs. Hocking, Komalavilas, Cheung-Flynn and Brophy are co-inventors on “Methods and Compositions for Vein Harvest and Autografting.” Vein harvest kit for reducing injury to saphenous vein grafts used for aortocoronary bypass or other procedures. (US 2011/0190572 A1).
References
Author Manuscript
1. Conte MS, Bandyk DF, Clowes AW, et al. Results of PREVENT III: a multicenter, randomized trial of edifoligide for the prevention of vein graft failure in lower extremity bypass surgery. Journal of vascular surgery. 2006 Apr; 43(4):742–751. discussion 51. [PubMed: 16616230] 2. Voskresensky IV, Wise ES, Hocking KM, et al. Brilliant blue FCF as an alternative dye for saphenous vein graft marking: effect on conduit function. JAMA surgery. 2014 Nov; 149(11):1176– 1181. [PubMed: 25251505] 3. Li FD, Eagle S, Brophy C, et al. Pressure control during preparation of saphenous veins. JAMA surgery. 2014 Jul; 149(7):655–662. [PubMed: 24759942] 4. Harskamp RE, Alexander JH, Schulte PJ, et al. Vein graft preservation solutions, patency, and outcomes after coronary artery bypass graft surgery: follow-up from the PREVENT IV randomized clinical trial. JAMA surgery. 2014 Aug; 149(8):798–805. [PubMed: 25073921]
Am Surg. Author manuscript; available in PMC 2016 July 01.
Wise et al.
Page 4
Author Manuscript Author Manuscript Figure 1. Components of the Optimized Preparation Kit
Author Manuscript
The cannula is fit with an introducer to facilitate easier insertion into the graft lumen. After removal of the introducer, the cannula connects with the pressure release valve (PRV), designed to limit distension pressures to 140 mmHg. The PRV is then attached to adaptor tubing which can be attached to a slip-tip syringe via the 3-way stopcock. The opposite end of the graft can be occluded with the bulldog clamp. After distension, the graft may be marked with an FCF-based marking pen
Author Manuscript Am Surg. Author manuscript; available in PMC 2016 July 01.
Am Surg. Author manuscript; available in PMC 2016 July 01. Published in final edited form as: Am Surg. 2015 July ; 81(7): E274–E276.
An Optimized Preparation Technique for Saphenous Vein Graft Eric S. Wise, MD1,ƚ, Kyle M. Hocking, PhD1,2, Daniel Feldman, BA1, Padmini Komalavilas, PhD1,3, Joyce Cheung-Flynn, PhD1, and Colleen M. Brophy, MD1,3 1Department
of Surgery, Vanderbilt University, Nashville TN, USA
2Department
of Biomedical Engineering, Vanderbilt University, Nashville TN, USA
Author Manuscript
3VA
Tennessee Valley Healthcare System, Department of Surgery, Division of Vascular Surgery, Nashville TN, USA
Author Manuscript
Human saphenous vein (HSV) remains the most widely used conduit for peripheral and coronary bypass procedures. However, data from the Project of Ex-Vivo vein graft Engineering via Transfection-III (PREVENT III) trial revealed vein graft failure rates of HSV as high as 40% at one year postoperatively.(1) While early vein graft failure (3,000 patients who underwent coronary artery bypass grafting) was stratified by type of preservation solution, including normal saline, buffered salt solutions or autologous whole blood. Controlling for baseline demographics and operative characteristics, those patients for whom a buffered salt solution (e.g. Plasma-Lyte A, University of Wisconsin solution) was used for graft preservation had a significant improvement in vein graft failure at one year, and trended toward a significant benefit at five years. Balanced salt solutions, designed considering physiologic pH and electrolyte composition, better preserved the HSV graft and reduced vein graft failure.(4) HSV graft is still frequently preserved in normal saline solution prior to implantation. Normal saline, while inexpensive and readily available, is acidic, with a pH < 6.0, mildly hyperosmolar and lacks cellular nutrients or antioxidants that may benefit the
Am Surg. Author manuscript; available in PMC 2016 July 01.
Wise et al.
Page 3
Author Manuscript
conduit. Therefore, the final component of the optimized preparation technique is the use of a balanced, pH-buffered salt solution such as Plasma-Lyte A as the preservation medium, to optimally preserve the graft, particularly the sensitive endothelial monolayer critical to maintenance of graft patency. Components of the OP bundled as a kit are illustrated in Figure 1. A brief demonstration of the OP is available as an mpeg-4 download at https://redcap.vanderbilt.edu/surveys/? s=HWC8NLAXLK, or for streaming at https://www.youtube.com/watch?v=OKogkvaiQ7I.
Author Manuscript
Vein graft preparation represents a unique window of opportunity in which conduit function can be augmented, potentially leading to enhanced vein graft patency. Recognizing an unmet clinical need, an optimized technique has been engineered to prepare HSV graft prior to implantation into the aortocoronary or peripheral circulation. The technique is effective at identifying leaks, maintaining graft orientation and dilating the conduit while requiring only simple modifications from current practice. In vivo studies are currently underway to determine whether there is concomitant improvement in intimal hyperplasia, using a porcine carotid interposition model.
Acknowledgments Grant Support Acknowledgment: This study was supported in part by resources and materials from the Veterans Affairs Tennessee Valley Healthcare System and by a Biomedical Laboratory Research and Development grant from the Department of Veterans Affairs to Dr Brophy. Dr Brophy was supported by grant R01HL70715-09 from the National Institutes of Health. Dr Cheung-Flynn was supported by grant R01HL105731-01A1 from the National Institutes of Health. Vanderbilt RedCAP is supported by the CTSA Award UL1 TR000445 from NCATS/NIH
Author Manuscript
Drs. Hocking, Komalavilas, Cheung-Flynn and Brophy are co-inventors on “Methods and Compositions for Vein Harvest and Autografting.” Vein harvest kit for reducing injury to saphenous vein grafts used for aortocoronary bypass or other procedures. (US 2011/0190572 A1).
References
Author Manuscript
1. Conte MS, Bandyk DF, Clowes AW, et al. Results of PREVENT III: a multicenter, randomized trial of edifoligide for the prevention of vein graft failure in lower extremity bypass surgery. Journal of vascular surgery. 2006 Apr; 43(4):742–751. discussion 51. [PubMed: 16616230] 2. Voskresensky IV, Wise ES, Hocking KM, et al. Brilliant blue FCF as an alternative dye for saphenous vein graft marking: effect on conduit function. JAMA surgery. 2014 Nov; 149(11):1176– 1181. [PubMed: 25251505] 3. Li FD, Eagle S, Brophy C, et al. Pressure control during preparation of saphenous veins. JAMA surgery. 2014 Jul; 149(7):655–662. [PubMed: 24759942] 4. Harskamp RE, Alexander JH, Schulte PJ, et al. Vein graft preservation solutions, patency, and outcomes after coronary artery bypass graft surgery: follow-up from the PREVENT IV randomized clinical trial. JAMA surgery. 2014 Aug; 149(8):798–805. [PubMed: 25073921]
Am Surg. Author manuscript; available in PMC 2016 July 01.
Wise et al.
Page 4
Author Manuscript Author Manuscript Figure 1. Components of the Optimized Preparation Kit
Author Manuscript
The cannula is fit with an introducer to facilitate easier insertion into the graft lumen. After removal of the introducer, the cannula connects with the pressure release valve (PRV), designed to limit distension pressures to 140 mmHg. The PRV is then attached to adaptor tubing which can be attached to a slip-tip syringe via the 3-way stopcock. The opposite end of the graft can be occluded with the bulldog clamp. After distension, the graft may be marked with an FCF-based marking pen
Author Manuscript Am Surg. Author manuscript; available in PMC 2016 July 01.
