The major drawbacks to the use of the saphenous vein for coronary bypass surgery are poor patency and harvest site complications. The novel “no-touch” (NT) method of vein harvest seems to significantly improve vein graft quality but is done with an open technique, which can lead to harvest site complications. Alternatively, endovascular harvesting of saphenous veins nearly eliminates harvest site complications; however, there is a reasonable concern that it is associated with enough conduit damage to impair patency.1 These opposing forces tug at the surgeon in opposite directions. Should the surgeon try to improve patency, or dismiss patency concerns and reduce leg complications? To explore this dilemma, we have compared the vein graft patency rate at symptom-directed cardiac catheterization of vein grafts harvested with either the NT or the endovascular technique. We have also assessed leg complications and possible methods to minimize them.
During the 2-year period of 2011 and 2012, data of all patients who had a coronary artery bypass with a saphenous vein as a component of either coronary artery bypass grafting (CABG) or valve/CABG were entered into a database. A record was also kept of all patients readmitted for cardiac catheterization for the period up to April 2013. All postoperative catheterizations were reviewed, and vein grafts were assigned a designation of patent or occluded (either 100% occluded or a stenosis of >80%). Patients who underwent a repeated catheterization did so at the discretion of their cardiologist, as part of a routine follow-up. The surgeons did not participate in any decision regarding recatheterization.
The decision to perform NT or endovascular harvest was left to the discretion of the surgeon. One surgeon exclusively used the NT technique; and the other surgeon, only occasionally. The NT technique was learned by reviewing published results2–4 and a video from Souza et al.5 After a short time, this knowledge was supplemented with personal training by Dr Souza’s group during a visit to Orebro, Sweden. The harvest method used was a modification of the Orebro technique. Most patients underwent a preoperative mapping of the greater saphenous vein by radiology in the ultrasound suite. Veins were harvested predominantly from the left leg, with a skin incision directly over the marked vein, with the incision extending from the ankle to the groin, if necessary. In the presence of significant peripheral vascular disease, the veins were harvested starting in the thigh, with the incision extending below the knee in most cases for adequate vein length. In general, a long section of vein was needed because the intention was to construct individual end-to-side grafts, with few sequential grafts, which is in contrast to the extensive use of sequential grafts in Orebro. The use of the sequential grafting technique in Orebro reduces the length of the vein harvest required.
The course of the vein was identified by looking through the less dense perivascular tissue when viewed anteriorly or posteriorly. An attempt was made to keep 5 mm of perivascular tissue around the lateral and medial sides of the vein. Initially, all dissection was performed with scissors, with identification and tying of the branches greater than 5 mm from the vein, as done in Orebro. The veins were then gently infused with saline or blood and then further tested with infusion of heparinized blood at systemic pressure from an aortic cannula. Any sites of bleeding were clipped. After 20 cases, the harvest method was changed by dissecting through fat and sealing side branches with the harmonic scalpel (Ethicon, Somerville, NJ USA). This was done to reduce potential bleeding sites on the conduit and to decrease bleeding from the leg during harvest. Grafts were left slightly long, with the perivascular tissue helping to prevent kinking. Great care was taken to ensure that the grafts did not flip and twist when the heart was lifted up. Graft flows in the NT group were usually measured with transit-time ultrasonography (VeriQ; Medi-Stim, Inc, Oslo, Norway). It was sometimes found that an NT graft could twist 180 degrees when the heart was placed down after checking for bleeding. This would be discovered by ultrasound, and the grafts would be repositioned. The incisions were closed in layers with running sutures and, in the later part of the study, after the application of autologous platelet-rich plasma (PRP) (Harvest Technologies Corp, Plymouth, MA USA). Platelet-rich plasma was prepared as directed, and recombinant thrombin was used instead of bovine thrombin. The patients were encouraged to use compression stockings after discharge, but compliance was poor.
Endovascular vein harvesting was performed by two physician assistants (PAs), one with greater than 10 years of experience, whereas the other was initially inexperienced (<100 cases). Harvesting was accomplished with a routine technique (Vasoview Hemopro, MAQUET Corp, Wayne, NJ USA). A heparin bolus was generally given before CO2 insufflation. Venous branches were divided with bipolar electrocautery at a setting of 30 W.
The patients were followed up in the office, until all incisions were well healed. Complications were divided into two groups, either minor or major. Mild-to-moderate cellulitis requiring oral antibiotics, small degrees of superficial wound separation, postoperative neuralgia, and edema were considered minor events. Cellulitis requiring intravenous antibiotics, application of vacuum-assisted wound closure, or follow-up in the wound care clinic was considered a major leg complication.
The patients were followed up routinely by their cardiologists. The patients were recatheterized at the discretion of the cardiologists for recurrence of symptoms. Data were then collected on the patients by reviewing charts.
To determine whether there was a difference in patency rates between the two surgeons or between the PAs with extensive or less extensive experience, the study on endovascular harvesting of veins was extended into the years of 2009 and 2010, a period in which NT harvesting was not used. Patency rates at recatheterization for the different groups were tabulated. The χ2 or the Fisher exact test was used to compare proportions using Excel.
This retrospective review was approved by the Western Institutional Review Board (Microsoft, Redmond, WA USA).
The characteristics of the patients in the study from 2011 to 2012 are listed in Table 1. There were no differences in preoperative characteristics of age, sex, presence of diabetes, peripheral vascular disease, history of smoking, hyperlipidemia, or ejection fraction. There were more CABG/valve procedures in the NT group. Operative characteristics were similar, with comparable bypass and cross-clamp times, grafts performed, percentage of LIMAs used, as well as percentage of radial arteries used. The percentage of patients who were discharged on postoperative statins (all of those without a statin contraindication) was similar between the two groups. There was no perioperative mortality in either group. The recatheterization rates for the two surgeons are listed in Table 3 and are not significantly different. The mean time to recatheterization for the NT group was 10.2 months; for the endo-vein group, the mean time was 7.5 months. The mean (SD) date from surgery to the date of completion of follow-up was 15.2 (7.1) months for the period 2011 to 2012; it was 40.2 (6.9) months for the years 2009 to 2010.
Figure 1 demonstrates the patency rates for vein grafts of symptom-directed cardiac recatheterization for the years 2011 to 2012. There was a significantly higher patency rate for the NT vein grafts (P < 0.018). The patency of endo-veins at symptom-directed cardiac catheterization for the years 2011 to 2012 was 26% and was not appreciably different during the period 2009 to 2012 (overall endo-vein patency, 37%). When compared with endo-veins during the 4-year period, the patency rate on symptom-directed cardiac catheterization was significantly higher for the NT veins (P < 0.014). There was a difference (P < 0.05) in patency rates for endo-vein harvest between the surgeons, but the patency for either surgeon was not good: surgeon A, 61%; surgeon B, 24%. When a PA operated with the surgeon who predominantly used endo-vein, there was no appreciable difference in patency when harvested with more (26%) or less (22%) experience. Two of the nine NT patients who underwent a recatheterization had an intervention; 7 of the 11 endo-vein patients who had a recatheterization had an intervention.
All 30 internal mammary grafts that were imaged in the two groups were patent. One internal mammary graft placed in an NT patient did have an anastomotic stenosis, and native vessel stenting was performed at recatheterization. The two radial arteries that were imaged at recatheterization were patent.
During the period of the study, seven patients died after discharge, five in the NT group and two in the endo-vein group. There was no significant difference in mortality (P < 0.12, χ2). One 87-year-old man died of multiorgan failure after coding secondary to a large pericardial effusion, 1 month after discharge. One patient died of pulmonary embolus, and one patient died of a gastrointestinal bleed. Two patients presumably had a cardiac arrest, with one of these two patients presenting with a cardiac arrest preoperatively. There were two mortalities in the endo-vein group, with one secondary to a pulmonary embolus and another secondary to an apparent cardiac arrest associated with urosepsis.
Figure 2 shows the complication rates for the endovascular and the NT harvest. The complications of the endovascular harvest were similar to those reported by others. The NT harvest complication rate was significantly higher than that for the endovascular group (P < 0.0001). The large percentage of patients in whom PRP was used had a similar complication rate as those without PRP (Fig. 4). In most of the patients, the vein was dissected and the branches were sealed with the harmonic scalpel (Harmonic Scalpel; Ethicon, Cincinnati, OH USA). There was no obvious difference in major complication rates with or without the use of the harmonic scalpel (Fig. 3).
There are two major ways to optimize the results of saphenous vein grafting: improve patency and decrease harvest site complications. The first approach is to alter the remodeling of the arterialized saphenous vein with different methods, such as the NT technique or gene therapy, and the second approach is to decrease harvest morbidity with an endovascular vein harvest. To date, there has been no direct comparison between veins harvested with the NT and the endo-vein technique. In this study, we have compared the graft patency on symptom-directed cardiac catheterization of veins harvested with the two different methods. We have shown that, in patients with symptoms, the NT technique has an excellent graft patency, significantly superior to endovascular vein conduits shortly after CABG. However, this improvement comes at the cost, with the methods used in this study, of a marked increase in harvest site morbidity.
Dr Souza’s group has accumulated an impressive amount of evidence documenting the benefits of preserving the vasa vasorum of the saphenous vein. There is a significant improvement in graft patency at short-term (1.4 years)3 and long-term (8.5 years)4 follow-up, a resistance to atherosclerosis,2 and even improved ventricular function at 15 years (unpublished data, DS, 2013). The retained perivascular tissue prevents mechanical kinking and better preserves endothelial covering and function, even if the veins are subjected to the well-known detrimental effects of distension.6 Possibly most important, the group has documented that the vasa vasorum directly drains into the vein lumen.7 This anatomy permits retrograde perfusion of oxygenated blood through the vasa vasorum upon arterialization, which results in an excellent blood supply to the outer one third of the media. This may reduce vein smooth muscle cell loss and subsequent replacement with fibrous tissue, as previously described.8 Thus, the vein graft is not necessarily obliged to become a fibrous tube, subjected to enhanced lipid deposition, with poor long-term results. To date, only the Swedish group has used the NT technique to preserve the vasa vasorum. Our results add limited but some additional evidence that this technique is potentially valuable.
Early reports on endovascular saphenous vein harvest suggested that the saphenous vein was of similar quality to a conventional harvest9 and caused lower postoperative morbidity.10,11 Patency rates were also shown to be similar.12–14 However, more recent reports have documented worrisome structural damage induced by endovascular harvesting,15 with the best results requiring a considerable amount of operator experience.16 In three more recent studies in which postoperative vein graft patency was evaluated with cardiac catheterization, there was a consistent, significantly lower patency with endo-vein harvest, sometimes associated with worse clinical outcomes.18–20 These observations have led England’s National Institute for Health and Clinical Excellence (NICE) to recommend the use of endovascularly harvested veins only with special arrangements for clinical governance, consent, and audit or research.21 The potential trade-off of patency for lower morbidity is a real concern.1
The NICE recommendation is controversial and has not changed the approach in the United States. Some support for the equality of patency with endo-vein grafts is the clinical observation on large cohort studies22 of a similar mortality compared with patients who underwent open harvest.23,24 If such a large number of patients can be operated on with no difference in mortality during the midterm, why not avoid the open vein harvest morbidity? However, differences in mortality might be seen only after a longer period, similar to the proven survival benefits of bilateral internal mammary arteries.25 Vein graft occlusions do not increase mortality early after surgery, probably because many grafts are placed into strategically less important vessels. A recent study of post-CABG patients with a documented vein graft stenosis showed a similar mortality or myocardial infarction rate but a higher repeated revascularization rate in patients with occluded rather than patent vein grafts.26 Thus, repeated revascularization is the metric that coincides with graft patency, and graft patency may be related to mortality only during the long-term. If the patency of the NT vein grafts is superior to the open harvest, there might be an even greater clinical downside to endo-vein harvest techniques during the long-term.
Only a small percentage of patients were recatheterized, and definitive conclusions on the difference in patency between endo-vein and NT grafts cannot be made with our study. It is difficult to separate the influence of the two surgeons and the PAs on patency rates. Our study group of recatheterized patients is not large enough to support a multivariate analysis. Most importantly, an assessment of all patients, including asymptomatic patients, is necessary. However, from a clinical perspective, the approach of examining only symptomatic patients has some strength. The data are available for review. All patients are not exposed to the slight risk for either recatheterization or computed tomographic scanning. Furthermore, the patients who are recatheterized have clinical issues that confront the cardiologist and the surgeon early after surgery. These early patency issues have to be addressed. An improvement in early patency might keep patients and cardiologists from losing faith in a surgical procedure in which a large percentage of vein conduits are occluded. Of course, the best antidote to these postoperative clinical problems is perfect patency, which might be more possible with multiarterial grafting, but for a variety of reasons, more aggressive arterial grafting is done in a relatively small percentage of cases.
It is clear from these data that a less invasive method of NT harvest would be helpful. Endovascular harvest is associated with minimal harvest site complications and increased patient satisfaction; the technique of NT harvest that we used resulted in a disappointing number of wound complications. In a sequential manner, several different strategies for NT harvest were tried: cold dissection with ligation of branches, dissection with the harmonic scalpel, and topical application of PRP. The wound complication rate reported here is higher than that found with Dr Souza’s group; different patient demographics are a likely explanation or perhaps a greater length of vein acquired because of the avoidance of sequential grafting. Although this was a small, nonrandomized study and any observations are not definitive, there was no apparent clinical advantage with any of these techniques that were tried to reduce harvest site complications.
Many patients gladly choose the option of NT harvest when presented with the patency versus harvest site dilemma, but a method must be developed to reduce complications so that more patients might enjoy the benefits of the NT technique.
1. Markar SR, Kutty R, Edmonds L, Sadat U, Nair S. A meta-analysis of minimally invasive versus traditional open vein harvest technique for coronary artery bypass graft surgery. Interact Cardiovasc Thorac Surg
. 2010; 10: 266–270.
2. Johansson BL, Souza DS, Bodin L, et al. Slower progression of atherosclerosis in vein grafts harvested with ‘no touch’ technique compared with conventional harvesting technique in coronary artery bypass grafting: an angiographic and intravascular ultrasound study. Eur J Cardiothorac Surg
. 2010; 38: 414–419.
3. Souza DS, Dashwood MR, Tsui JC, et al. Improved patency in vein grafts harvested with surrounding tissue: results of a randomized study using three harvesting techniques. Ann Thorac Surg
. 2002; 73: 1189–1195.
4. Souza DS, Johansson B, Bojö L, et al. Harvesting the saphenous vein with surrounding tissue for CABG provides long-term graft patency comparable to the left internal thoracic artery: results of a randomized longitudinal trial. J Thorac Cardiovasc Surg
. 2006; 132: 373–378.
6. Dashwood MR. Distension of the saphenous vein during graft preparation: markers of inflammation or endothelium? Ann Thorac Surg
. 2012; 94: 2177–2178.
7. Dreifaldt M, Souza DS, Loesch A, et al. The “no-touch” harvesting technique for vein grafts in coronary artery bypass surgery preserves an intact vasa vasorum. J Thorac Cardiovasc Surg
. 2011; 141: 145–150.
8. O’Brien JE Jr, Ormont ML, Shi Y, Wang D, Zalewski A, Mannion JD. Early injury to the media after saphenous vein grafting. Ann Thorac Surg
. 1998; 65: 1273–1278.
9. Griffith GL, Allen KB, Waller BF, et al. Endoscopic and traditional saphenous vein harvest: a histologic comparison. Ann Thorac Surg
. 2000; 69: 520–523.
10. Andreasen JJ, Nekrasas V, Dethlefsen C. Endoscopic vs open saphenous vein harvest for coronary artery bypass grafting: a prospective randomized trial. Eur J Cardiothorac Surg
. 2008; 34: 384–389.
11. Cadwallader RA, Walsh SR, Cooper DG, Tang TY, Sadat U, Boyle JR. Great saphenous vein harvesting: a systematic review and meta-analysis of open versus endoscopic techniques. Vasc Endovascular Surg
. 2009; 43: 561–566.
12. Perrault LP, Jeanmart H, Bilodeau L, et al. Early quantitative coronary angiography of saphenous vein grafts for coronary artery bypass grafting harvested by means of open versus endoscopic saphenectomy: a prospective randomized trial. J Thorac Cardiovasc Surg
. 2004; 127: 1402–1407.
13. Yun KL, Wu Y, Aharonian V, et al. Randomized trial of endoscopic versus open vein harvest for coronary artery bypass grafting: six-month patency rates. J Thorac Cardiovasc Surg
. 2005; 129: 496–503.
14. Davis Z, Garber D, Clark S, et al. Long-term patency of coronary grafts with endoscopically harvested saphenous veins determined by contrast-enhanced electron beam computed tomography. J Thorac Cardiovasc Surg
. 2004; 127: 823–828.
15. 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.
16. Desai P, Kiani S, Thiruvanthan N, et al. Impact of the learning curve for endoscopic vein harvest on conduit quality and early graft patency. Ann Thorac Surg
. 2011; 91: 1385–1391.
17. Kiani S, Desai PH, Thirumvalavan N, et al. Endoscopic venous harvesting by inexperienced operators compromises venous graft remodeling. Ann Thorac Surg
. 2012; 93: 11–17.
18. Lopes RD, Hafley GE, Allen KB, et al. Endoscopic versus open vein-graft harvesting in coronary-artery bypass surgery. N Engl J Med
. 2009; 361: 235–244.
19. Puskas JD, Halkos ME, Balkhy H, et al. Evaluation of the PAS-Port Proximal Anastomosis System in coronary artery bypass surgery (the EPIC trial). J Thorac Cardiovasc Surg
. 2009; 138: 125–132.
20. Zenati MA, Shroyer AL, Collins JF, et al. Impact of endoscopic versus open saphenous vein harvest technique on late coronary artery bypass grafting patient outcomes in the ROOBY (Randomized On/Off Bypass) Trial. J Thorac Cardiovasc Surg
. 2011; 141: 338–344.
21. Barnard JB, Keenan DJ. Endoscopic saphenous vein harvesting for coronary artery bypass grafts: NICE guidance. Heart
. 2011; 97: 327–329.
22. Ouzounian M, Hassan A, Buth KJ, et al. Impact of endoscopic versus open saphenous vein harvest techniques on outcomes after coronary artery bypass grafting. Ann Thorac Surg
. 2010; 89: 403–408.
23. Dacey LJ, Braxton JH Jr, Kramer RS, et al. Long-term outcomes of endoscopic vein harvesting
after coronary artery bypass grafting. Circulation
. 2011; 123: 147–153.
25. Lytle BW, Blackstone EH, Sabik JF, Houghtaling P, Loop FD, Cosgrove DM. The effect of bilateral internal thoracic artery grafting on survival during 20 postoperative years. Ann Thorac Surg
. 2004; 78: 2005–2012.
26. Lopes RD, Mehta RH, Hafley GE, et al. Relationship between vein graft failure and subsequent clinical outcomes after coronary artery bypass surgery. Circulation
. 2012; 125: 749–756.
This study examined vein graft patency at symptom-directed cardiac catheterization and wound complication rates in patients who underwent either a “no-touch” saphenous vein harvesting procedure or endoscopic vein harvest. The recatheterization rates for the two groups were similar. There was a significantly better vein graft patency with the no-touch technique when compared with the endoscopic method. Conversely, there were significantly more harvest site complications using the no-touch technique. This is a provocative study and suggests that the no-touch harvest technique should be both more widely studied and perhaps more widely adopted. Most vein harvests in North America and Europe are now carried out using endoscopy. However, this study would suggest that there may need to be a reevaluation of this approach.
However, this was a very small study consisting of only 20 patients who underwent recatheterization for symptoms. The definitive conclusions on patency would need to be assessed by a prospective, randomized trial or a much larger retrospective series. It is also clear from the data in this study that strategies to reduce the high wound complication rate with the no-touch technique would need to be developed before its widespread application.