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Ann Thorac Surg 2005;80:2407-2414
© 2005 The Society of Thoracic Surgeons

Review

Does Minimally Invasive Vein Harvesting Technique Affect the Quality of the Conduit for Coronary Revascularization?

Omer Aziz, MRCS, Thanos Athanasiou, PhD, FETCS * , Sukhmeet Singh Panesar, BS, Rachel Massey-Patel, MBBS, Oliver Warren, MBBS, James Kinross, MRCS, Sanjay Purkayastha, MRCS, Roberto Casula, FETCS, Brian Glenville, FRCS, Ara Darzi, KBE, FRCS

Departments of Cardiothoracic Surgery and Surgical Oncology and Technology, Imperial College of Science, Technology and Medicine, St. Mary's Hospital, London, United Kingdom

Accepted for publication April 5, 2005.

Abbreviations and Acronyms CABG = coronary artery bypass grafting; CI = confidence interval; CVH = conventional vein harvesting; HG = heterogeneity; MI = myocardial infarction; MIVH = minimally invasive vein harvesting; MRA = magnetic resonance angiography; OR = odds ratio; WMD = weighted mean difference

* Address correspondence to Dr Athanasiou, Department of Cardiothoracic Surgery, St. Mary's Hospital, 70 St Olaf's Rd, Fulham, London, SW6 7DN UK (Email: tathan5253{at}aol.com).


   Abstract
Top
 Abstract
Introduction
 Material and Methods
 Results
 Comment
 References
 
The effect of minimally invasive great saphenous vein harvest on patient morbidity (wound infection and other healing disturbances) has been extensively investigated, yet its impact on the quality of the venous conduit is less well known. This study aims to review the literature with regard to macroscopic quality, postoperative myocardial infarction rates, and angiographic patency of the minimally invasive versus conventionally harvested vein using meta-analytic techniques where appropriate. Results suggest that conduits are comparable in macroscopic quality with minimally invasively harvested veins requiring more repairs prior to grafting. Postoperative myocardial infarction rates were not significantly different between groups, which is supported by the limited evidence on angiographic patency.


   Introduction
Top
 Abstract
 Introduction
Material and Methods
 Results
 Comment
 References
 
Minimally invasive harvesting (MIVH) of the great saphenous vein for coronary artery bypass grafting (CABG) has been shown to reduce patient-related morbidity in the postoperative period as compared with conventional vein harvesting (CVH). In two separate meta-analyses comparing the reported incidence of infective and non-infective wound healing disturbances between conventional and minimally invasive techniques, we have found a significantly lower rate of wound infection, hematoma, edema, skin necrosis, dehiscence, wound drainage, seroma formation, and length of stay in patients undergoing MIVH [1, 2]. Although the effect of MIVH on patient morbidity from wound-related complications has been extensively investigated in the literature, its effect on the quality of the harvested conduit is less clear. However, before attempting this comparison, it is important to consider the characteristics that would be expected of a high quality conduit, namely its macroscopic appearance, histologic quality (with particular regard to endothelial continuity), functional characteristics, and mid-term and long-term patency.

Macroscopic features that have been reported when comparing MIVH and CVH of great saphenous venous conduits include length, number of injuries (such as side branch avulsions or tears), and the number of repairs required before grafting can take place [3]. Several scoring systems have been devised to compare the macroscopic quality of MIVH versus CVH of veins, ranging from a simple "good" to "fair" to "poor" assessment [4] to numerical grading systems based on the caliber, varicosities, wall thickness, and tears requiring repair [5].

The histological quality of MIVH as compared with CVH conduits has been assessed using light [6], scanning [7], and transmission electron microscopy [8], with some groups attempting to measure the microscopic damage using scoring systems [5, 9]. Despite this there is an absence of standardization in measurement of histologic quality between studies making direct comparisons impossible. Similarly, although the functional properties (vascular reactivity, endothelial cell viability, and release of inflammatory markers during harvest) of MIVH versus CVH conduits have been compared [10, 11], the lack of standardization in measurements, solutions, and stimulants in which the veins are exposed means that meta-analysis of these results is also not possible.

The ultimate measure of quality of a conduit used for CABG is its long-term patency. With some figures suggesting saphenous vein graft occlusion rates of 15% to 30% within the first year of CABG, increasing to more than 50% at 10 years after CVH, its important to assess the effect of MIVH on this outcome [12]. Although patency can be assessed by serial coronary angiography, the cost and invasiveness of this investigation makes it unattractive. Recent advances in imaging techniques (such as the use of contrast-enhanced electron beam computer tomography [13] and magnetic resonance angiography) [6] have meant that saphenous vein graft patency may now be evaluated in a noninvasive manner. Indirect measures that may be used to assess graft patency include reintervention rates (coronary angioplasty or redo CABG) and postoperative myocardial infarction (MI).

This meta-analytic review aims to compare MIVH and CVH conduits with regard to length of the harvested vein, macroscopic scoring of conduit quality (ie, good, fair, or poor), proportion of veins harvested requiring repair, and number of repairs to the harvested vein, incidence of postoperative MI, and angiographic patency. It also aims to perform subgroup analysis focusing on the best available evidence (randomized studies) to assess the effect of study design on heterogeneity (HG).


   Material and Methods
Top
 Abstract
 Introduction
 Material and Methods
Results
 Comment
 References
 
Study Selection
A literature search was performed using MEDLINE, Ovid, Embase, and Cochrane databases. All studies published between 1997 and 2004 comparing MIVH with CVH techniques for CABG were included. Conventional vein harvesting was defined as harvesting either with a continuous skin incision or multiple interrupted incisions along the length of the great saphenous vein. The minimally invasive great saphenous vein was defined as harvesting of the vein using endoscopic or non-endoscopic instruments. The following mesh headings were used: "comparative study," "coronary artery bypass," "surgical procedures, minimally invasive," "endoscopy," "vein graft patency," and "disease-free survival." The related articles database function was utilized to broaden the search, and all abstracts, studies, and citations were scanned and reviewed.

Data Extraction
Two reviewers (AO and AT), independently extracted the following data from each study: first author, year of publication, study population characteristics, study design, number of subjects operated on with each technique, and outcomes of interest as previously mentioned.

Outcomes of Interest and Definitions
The following outcomes of interest were used to assess the quality of the harvested veins: (1) vein length; (2) macroscopic scoring by surgeon ("good," "fair," or "poor"); (3) proportion of veins requiring repair; (4) number of repairs to each vein; (5) incidence of postoperative myocardial infarction; and (6) angiographic patency.

Postoperative myocardial infarction was defined as Q-wave or non-Q-wave myocardial infarction occurring at any time from the perioperative period to 1 year postoperatively. A macroscopic quality of "good" was assigned when the conduit was scored as "good" in the study, "fair" when the conduit was scored as either "fair", "satisfactory" or "fairly good", and "poor" when the conduit was scored as "poor" or "bad" in the study.

Criteria for Inclusion in the Meta-Analysis
In order to be included in our meta-analysis, the studies had to contain the following criteria:

1 compare MIVH and CVH techniques;
2 be located at single institutions;
3 report on at least one of the outcome measures mentioned as follows;
4 contain a previously unreported patient group; if patient material was reported more than once, the most informative and recent article was chosen;
5 clearly document the term "minimally invasive" as either endoscopic or non-endoscopic great saphenous vein harvest;
6 when two studies were reported by the same institution, our analysis included either the one of better quality (randomized) or the most recent publication.

Equipment used for endoscopic MIVH included: (1) Ethicon Endo-Surgery Vein Harvest Equipment (Ethicon Endo-Surgery, Inc, Cincinnati, OH), (2) VasoView (Guidant Medsystems, Inc, Menlo Park CA), (3) Karl Storz Endoskope (Karl Storz, Tuttlingen, Germany), (4) Clearglide Accel (Cardiovations, Edinburgh, Scotland), or (5) a combination of these instruments.

Equipment used for non-endoscopic MIVH included: (1) Mini-Harvest System (Autosuture [USSC, Norwalk, CT]), (2) SaphLITE System (Genzyme Surgical Products, Cambridge, MA), (3) Aesculap Retractor (Aesculap AGCoKG, Tutligen, Germany), or (4) Mayo Vein Stripper (Johnson and Johnson).

Criteria for Exclusion From the Meta-Analysis
The following criteria were used to exclude studies from our analysis: (1) studies in which the mode of harvesting could not be extracted; (2) studies in which the outcomes of interest were not reported for the two techniques or was impossible to calculate from the published results; and (3) studies that displayed a zero for the outcomes of interest in both MIVH and CVH groups.

Statistical Analysis
Meta-analysis was performed in line with recommendations from the Cochrane Collaboration and the Quality of Reporting of Meta-analyses guidelines [14, 15]. Statistical analysis for categorical variables was carried out using the odds ratio (OR) as the summary statistic. This ratio represents the odds of an adverse event occurring in the treatment group or MIVH group compared with the reference (CVH) group. An OR of less than one favors the treatment group, and the point estimate of the OR is considered statistically significant at the p < 0.05 level if the 95% confidence interval does not include the value one.

The Mantel-Haenszel method was used to combine the odds ratio for the outcomes of interest. The Yate's correction method was used for those studies that contained a zero in one cell for the number of events of interest in one of the two groups [16, 17]. These "zero cells" create problems with the computation of ratio measure and its standard error of the treatment effect. This was resolved by adding the value 0.5 in each cell of the 2 x 2 table for the study in question, and if there were no events for both MIVH and CVH groups, the study was discarded from the meta-analysis.

In this study we used random effect models. In a random effect model it is assumed that there is variation between studies, and thus the calculated OR has a more conservative value [18, 19]. In surgical research, meta-analysis using the random effect model is preferable, particularly because patients that are operated on in different centers have varying risk profiles and selection criteria for each surgical technique.

In the tabulation of our results (Fig 1), squares indicate point estimates of treatment effect (OR), with the size of the square representing the weight attributed to each study, and 95% confidence intervals are indicated by horizontal bars. The diamond represents the summary OR from the pooled studies with 95% confidence intervals.



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  		Fig 1. Results of meta-analysis of postoperative myocardial infarction. {diamondsuit} = the summary OR from the pooled studies with 95% confidence intervals; {blacksquare} = point estimates of treatment effect (OR), with the size of the square representing the weight attributed to each study; horizontal bars = 95% confidence intervals. (CI = confidence interval; MI = myocardial infarction; MIVH = minimally invasive vein harvesting; OR = odds ratio.)

 
For continuous variables, such as length of harvested vein and number of repairs required per vein, statistical analysis was carried out using the weighted mean difference (WMD) as the summary statistic [19]. For studies that presented continuous data as mean and range values, the standard deviation was calculated using statistical algorithms and was checked using "bootstrap" re-sampling techniques. Thus, all continuous data were standardized for analysis. In Figures 2 and 3, Go squares indicate point estimates of treatment effect (ie, WMD), with 95% confidence intervals indicated by horizontal bars. The diamond represents the summary from the pooled studies with 95% confidence intervals. The point estimate is considered statistically significant at the p < 0.05 level if the 95% confidence interval does not include the vertical bar.



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  		Fig 2. Results of meta-analysis of length of the venous conduit. {diamondsuit} = the summary from the pooled studies with 95% confidence intervals; {blacksquare} = point estimates of treatment effect (ie, WMD); horizontal bars = 95% confidence intervals. (CI = confidence interval; MIVH = minimally invasive vein harvesting; SD = standard deviation; WMD = weighted mean difference.) Note that the point estimate is considered statistically significant at the p < 0.05 level if the 95% confidence interval does not include the vertical bar.

 


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  		Fig 3. Results of meta-analysis of number of repairs required to the venous conduit. {diamondsuit} = the summary from the pooled studies with 95% confidence intervals; {blacksquare} = point estimates of treatment effect (ie, WMD); horizontal bars = 95% confidence intervals. (CI = confidence interval; MIVH = minimally invasive vein harvesting; SD = standard deviation; WMD = weighted mean difference.) Note that the point estimate is considered statistically significant at the p < 0.05 level if the 95% confidence interval does not include the vertical bar.

 
In order to quantitatively assess heterogeneity, sensitivity analysis was undertaken using subgroup analysis of only randomized trials. Meta-analyses of these trials were then compared with the overall results, and the effects on heterogeneity were noted.

Analysis was conducted by using the statistical software SPSS version 12.0 for Windows (SPSS Inc, Chicago, IL); Intercooled Stata version 7.0 for Windows (Stata Corporation, College Station, TX); and Review Manager, version 4.2 (The Cochrane Collaboration, Software Update, Oxford, UK).


   Results
Top
 Abstract
 Introduction
 Material and Methods
 Results
Comment
 References
 
Studies Included
The literature search identified 34 comparative studies matching the selection criteria [3–7, 20–48] from which two studies were excluded because they contained a previously reported patient group [46, 47]. Table 1 shows the remaining 31 studies that were included in this meta-analysis and the outcomes of interest reported by them. It is worth noting that more than one study by the same author was included in our meta-analysis in two cases [3, 21, 28, 43]. In the case of the studies by Bonde and colleagues [3, 43], the study published in 2002 reported on vein length, whereas the study published in 2004 reported on macroscopic scoring of the conduit and postoperative myocardial infarction. Similiarly, in the case of studies by Folliguet and colleagues [21, 28], the study published in 1998 reported on proportion of veins requiring repair, whereas the study published in 1999 reported on the length of the harvested vein.


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  		Table 1. Characteristics of Studies Included in Meta-Analysis of Macroscopic Quality and Postoperative Myocardial Infarction
 
Meta-Analysis of Length of the Harvested Vein
Eighteen studies reported on the length of the harvested vein [3–5, 20, 22, 24–26, 28–36, 44], with 1,086 veins harvested in the MIVH group compared with 945 in the CVH group. The results ranged from 29.5 to 64.1 cm in the MIVH group compared with 30.2 to 63.5 cm in the CVH group. When all studies were considered, there was no significant difference in the length of the venous conduit between the two harvesting techniques (WMD, –0.09; confidence interval [CI] –1.54 to 1.36) as shown in Figure 2. This was also true when only the nine randomized studies were considered [3, 4, 44, 20, 28, 29, 32, 34, 35] (WMD, 0.77; CI –0.77 to 2.31), although one of these studies compared three different MIVH techniques with CVH separately [4].

Meta-Analysis of Proportion of Harvested Veins Requiring Repair
Four studies reported on the proportion of veins requiring repair [7, 21, 22, 39] with 277 veins harvested in the MIVH group compared with 148 veins harvested in the CVH group. The number of veins requiring repair was 59 of 277 (21.3%) in the MIVH group as compared with 33 of 148 (22.3%) in the CVH group. The difference in this outcome between the two groups was not significant (OR, 0.84; CI, 0.45 to 1.55). Three of these studies were randomized [7, 21, 39], and consideration of these also did not show any significant difference between MIVH and CVH techniques (OR, 0.97; CI, 0.33 to 2.89).

Meta-Analysis of Number of Repairs to Each Harvested Vein
Four studies gave results for the number of repairs to each harvested vein in the MIVH group versus the CVH group [20, 32, 34, 38]. The number of repairs per vein ranged from 1.1 to 2.8 with MIVH as compared with 0.4 to 0.8 with CVH. This difference was statistically significant with a WMD of 1.28 (CI, 0.52 to 2.04). The results of this meta-analysis are shown in Figure 3. Consideration of the three randomized studies [20, 32, 34] also showed a significant difference between the groups (OR, 1.59; CI, 1.09 to 2.1).

Meta-Analysis of Surgeon-Assessed Macroscopic Quality of Vein
Four studies reported on the macroscopic quality of the vein as "good," "fair," or "poor," with 172 veins assessed in the MIVH as compared with 149 in the CVH group [4, 25, 26, 43]. The proportion of veins reported as being of "good" quality was 121 of 172 (70.3%) in the MIVH group and 86 of 149 (57.8%) in the CVH group. This difference was not statistically significant (OR, 2.06; CI, 0.99 to 4.29). Consideration of the two randomized studies [4, 43] did not show any significant difference between the groups (OR, 2.08; CI, 0.73 to 5.94).

Meta-Analysis of Postoperative MI
Seven studies documented the postoperative MI rate, reporting on 927 MIVH patients and 967 CVH patients [20, 23, 27, 37, 40, 41, 43]. The rate of MI was 15 of 927 (1.6%) with MIVH as compared with 12 of 967 (1.2%) with CVH, a result that was not statistically significant (OR, 1.16; CI, 0.54 to 2.49). The results of this meta-analysis are shown in Figure 1. Consideration of the three randomized studies [20, 40, 43] reporting postoperative MI did not show a significant difference between the groups (OR, 1.51; CI, 0.29 to 7.97).

Angiographic Patency
Four comparative studies reporting on angiographic patency of MIVH versus CVH conduits were identified [6, 42, 45, 48]. In a prospective nonrandomized study of 17 patients undergoing endoscopic MIVH versus 15 patients undergoing CVH, Perrault and colleagues [45] used quantitative coronary angiography to assess early graft patency at a mean of 3 months after CABG. They did not identify any significant difference in graft stenosis (> 50% of internal graft diameter) in the MIVH group versus the CVH group. In a separate prospective randomized study, Allen and colleagues [42] assessed long-term angiographic patency (during a 5-year follow-up period) in 10 selected patients (5 MIVH patients and 5 CVH patients). In each group, 4 of 5 patients had saphenous vein graft closures with stenoses of greater than 50% being found in 3 of 5 MIVH patients and 2 of 5 CVH patients. This difference was not statistically significant. A randomized trial of endoscopic versus open vein harvest by Yun and colleagues [48] reported 166 MIVH grafts and 170 CVH grafts were assessed at 6 months after CABG with comparable overall occlusion (21.7% versus 17.6%, respectively) and greater than 50% stenosis rates (10.2% vs 12.4%, respectively). Using ordinal hierarchic logistical regression, MIVH was not found to be a risk factor for vein graft occlusion or disease. Finally, magnetic resonance angiography and thallium scanning was used by O'Regan and colleagues [6] to assess graft patency 1 year after CABG in 9 patients undergoing both non-endoscopic MIVH and CVH. Saphenous vein graft patency was identified as 89% using thallium scanning and 92% using magnetic resonance angiography (ie, rates that the authors concluded were comparable with CVH grafts). Due to the small sample size, varying follow-up period, and mode of assessment of patency, these results were not suitable for meta-analysis.

Sensitivity Subgroup Analysis Results
With regard to the length of the harvested great saphenous vein, HG was lowest only when randomized studies were considered (HG = 18.92; p = 0.04) as compared with all studies being included (HG = 82.31; p < 0.00001). The same was true for postoperative MI in which randomized studies HG was 1.09 (p = 0.58) compared with 4.09 (p = 0.77) with all studies, and the number of repairs to each vein in which randomized studies HG was 3.35 (p = 0.19) compared with 16.93 (p = 0.0007) with all studies.


   Comment
Top
 Abstract
 Introduction
 Material and Methods
 Results
 Comment
References
 
The results of this meta-analysis suggested that MIVH and CVH conduits are comparable with regards to length, proportion of veins requiring repair, and surgeon-assessed macroscopic grading of the harvested vein, but that MIVH conduits required a significantly larger number of repairs. It is important that conduit length is maintained with MIVH, as this determines not only the number of grafts for which a single vein can be used, but also because the use of a single great saphenous vein for all grafts reduces the need for bilateral leg wounds and the morbidity associated with it. The macroscopic assessment of quality at time of operation is important because it is a measure used by the operating surgeon to determine whether the vein is suitable for use in CABG. A graft that appears damaged is unlikely to be used for a CABG graft and will result in another conduit being harvested, again resulting in further patient morbidity. We acknowledge that macroscopic assessment and scoring by the operative surgeon is a measure that has limitations, namely the fact that it is too subjective and that it may be affected by the inherent qualities of the vein and not just the harvest technique.

The finding that veins harvested with MIVH techniques requires almost twice the rate of repair compared with CVH (WMD, 1.28; CI, 0.52 to 2.04) is likely to be explained by the increased traction applied to the vein during MIVH. Subgroup analysis using randomized studies produced similar results, again displaying a significantly higher rate of vein repair with MIVH (OR, 1.59; CI, 1.09 to 2.1). Sensitivity analysis results using randomized studies highlighted lower heterogeneity when only the randomized studies were being considered, confirming the effect of study design on heterogeneity. One of the theoretical benefits of endoscopic MIVH is that it allows the harvest to occur entirely under direct vision and has the potential to reduce trauma and traction to the vein and surrounding tissues. The evolution of endoscopic MIVH techniques has meant that changes such as the adoption of carbon dioxide insufflation during dissection and the increasing use of harmonic scalpel or bipolar cautery have taken place, with the effect of this on the quality of the harvested conduit undetermined. This study was unable to answer the question of whether endoscopic MIVH results in a lower number of repairs to the conduit, as only two of the four studies reporting number of vein repairs in the harvested conduit used an endoscopic MIVH technique [20, 38]. The time taken to harvest the great saphenous vein for CABG and its effect on the quality of the conduit is another factor that must be taken into account. Minimally invasive great saphenous techniques have the advantage of reducing wound lengths potentially resulting in quicker closure, but invariably take longer to harvest the vein. Finally, it is important to note that there is a learning curve associated with both endoscopic and non-endoscopic MIVH techniques, which has the potential to affect the number of repairs required to the conduit.

Patency of the grafted conduit may be measured either directly using invasive and noninvasive angiographic techniques, or indirectly by examining the rate of postoperative MI after CABG. Meta-analysis of this latter indirect measure did not reveal a statistical difference between the MIVH group and the CVH group. There are at present three randomized studies in the published literature that report the use of coronary angiography to compare short-term patency (ie, less than 6 months) after CABG using minimally invasive conduits versus conventionally harvested conduits, all of which report similar results with both techniques [42, 45, 48]. The only mid-term patency data available for MIVH grafts is noncomparative and describes overall patency of endoscopically harvested grafts to be just slightly greater than 95% [49]. With the development of computed tomography and magnetic resonance angiography techniques, patency may now be assessed less invasively and at lower cost, thereby allowing further investigation of the patency of MIVH grafts.

There were several limitations of this study. First, varying definitions for macroscopic measures of quality meant that many of the studies could not be included in this meta-analysis. Second, despite our efforts at standardization, our outcome measures were less well defined and therefore less absolute than we would have ideally liked. Third, neither the allocation of treatment nor the assessment of outcome was blinded, with much variation in the instrumentation used for MIVH. Fourth, it is important to bear in mind publication bias, particularly in meta-analytic research based on published studies. Finally, there was variation in the inclusion criteria, type of randomization used, treatment protocols, and outcome assessment between studies. Histologic properties and functional characteristics of the conduit are important aspects of conduit quality that have not been covered in this meta-analysis due to the absence of standardized data.

The results of this meta-analysis suggest that the macroscopic quality of the conduit after MIVH of the great saphenous vein is comparable with CVH, adding to previous findings that MIVH for CABG significantly reduces wound-related patient morbidity [1, 2]. The finding that postoperative MI was not significantly different after CABG using MIVH and CVH conduits is important, as presently it is the only indirect measure of graft patency available when comparing the two techniques. Further comparative research on angiographic patency using computed tomography, magnetic resonance angiography, and direct coronary angiography techniques is eagerly awaited and will help to conclusively answer the question of whether MIVH and CVH grafts are comparable in their quality.


   References
Top
 Abstract
 Introduction
 Material and Methods
 Results
 Comment
 References
 

  1. Athanasiou T, Aziz O, Skapinakis P, et al. Leg wound infection after coronary artery bypass graftinga meta-analysis comparing minimally invasive versus conventional vein harvesting. Ann Thorac Surg 2003;76(6):2141-2146.[Abstract/Free Full Text]
  2. Athanasiou T, Aziz O, Al-Ruzzeh S, et al. Are wound healing disturbances and length of hospital stay reduced with minimally invasive vein harvest? A meta-analysis Eur J Cardiothorac Surg 2004;26(5):1015-1026.[Abstract/Free Full Text]
  3. Bonde P, Graham A, MacGowan S. Endoscopic vein harvestearly results of a prospective trial with open vein harvest. Heart Surg Forum 2002;5(Suppl 4):S378-S391.
  4. Cisowski M, Wites M, Gerber W, et al. Minimally invasive saphenous vein harvesting for coronary artery bypass grafting–comparison of three less invasive methods Med Sci Monit 2000;6(4):735-739.[Medline]
  5. Tran HM, Paterson HS, Meldrum-Hanna W, Chard RB. Tunnelling versus open harvest technique in obtaining venous conduits for coronary bypass surgery Eur J Cardiothorac Surg 1998;14(6):602-606.
  6. O'Regan DJ, Borland JA, Chester AH, et al. Assessment of human long saphenous vein function with minimally invasive harvesting with the Mayo stripper Eur J Cardiothorac Surg 1997;12(3):428-435.[Abstract]
  7. Fabricius AM, Diegeler A, Doll N, et al. Minimally invasive saphenous vein harvesting techniquesmorphology and postoperative outcome. Ann Thorac Surg 2000;70(2):473-478.[Abstract/Free Full Text]
  8. Alrawi SJ, Balaya F, Raju R, et al. A comparative study of endothelial cell injury during open and endoscopic saphenectomyan electron microscopic evaluation. Heart Surg Forum 2001;4(2):120-127.[Medline]
  9. Lamm P, Juchem G, Milz S, Reichart B. Continuous graft perfusionoptimizing the quality of saphenous vein grafts. Heart Surg Forum 2002;5(Suppl 4):S355-S361.
  10. Alrawi SJ, Samee M, Raju R, et al. Intercellular and vascular cell adhesion molecule levels in endoscopic and open saphenous vein harvesting for coronary artery bypass surgery Heart Surg Forum 2000;3(3):241-245.[Medline]
  11. Alrawi SJ, Raju R, Alshkaki G, et al. Saphenous vein endothelial cell viabilitya comparative study of endoscopic and open saphenectomy for coronary artery bypass grafting. JSLS 2001;5(1):37-45.[Medline]
  12. Mehta D, Izzat MB, Bryan AJ, Angelini GD. Towards the prevention of vein graft failure Int J Cardiol 1997;62(Suppl 11):S55-S63.
  13. 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(3):823-828.[Abstract/Free Full Text]
  14. Clarke. Cochrane Reviewers Handbook 4.1.3. The Cochrane Library: Oxford, UK: Update Software, 2001..
  15. Moher D, Cook DJ, Eastwood S, et al. Improving the quality of reports of meta-analyses of randomised controlled trials: the QUOROM statement. Quality of Reporting of Meta-analyses Lancet 1999;354(9193):1896-1900.[Medline]
  16. Yusuf S, Peto R, Lewis J, Collins R, Sleight P. Beta blockade during and after myocardial infarctionan overview of the randomised trials. Prog Cardiovasc Dis 1985;27:335-371.[Medline]
  17. Mantel N, Haenszel W. Statistical aspects of the analysis of data from retrospective studies of disease J Natl Cancer Inst 1959;22:719-748.
  18. Egger M, Davey Smith G, Schneider M, Minder C. Bias in meta-analysis detected by a simple, graphical test BMJ 1997;315(7109):629-634.[Abstract/Free Full Text]
  19. DerSimonian R, Laird N. Meta-analysis in clinical trials Control Clin Trials 1986;7(3):177-188.[Medline]
  20. Allen KB, Griffith GL, Heimansohn DA, et al. Endoscopic versus traditional saphenous vein harvestinga prospective, randomized trial. Ann Thorac Surg 1998;66(1):26-31discussion 31–2.[Abstract/Free Full Text]
  21. Folliguet TA, Le Bret E, Moneta A, et al. Endoscopic saphenous vein harvesting versus "open" techniquea prospective study. Eur J Cardiothorac Surg 1998;13(6):662-666.
  22. Davis Z, Jacobs HK, Zhang M, et al. Endoscopic vein harvest for coronary artery bypass graftingtechnique and outcomes. J Thorac Cardiovasc Surg 1998;116(2):228-235.[Abstract/Free Full Text]
  23. Pagni S, Ulfe EA, Montgomery WD, et al. Clinical experience with the video-assisted saphenectomy procedure for coronary bypass operations Ann Thorac Surg 1998;66(5):1626-1631.[Abstract/Free Full Text]
  24. Li JY, Wang SS, Lin FY, et al. Video-assisted endoscopic saphenous vein harvesting for coronary artery bypass grafting J Formos Med Assoc 1998;97(12):819-825.[Medline]
  25. Tevaearai HT, Mueller XM, von Segesser LK. [Minimally invasive internal saphenous vein harvesting for coronary artery bypass] Swiss Surg 1998(Suppl 2):8-11.
  26. Morris RJ, Butler MT, Samuels LE. Minimally invasive saphenous vein harvesting Ann Thorac Surg 1998;66(3):1026-1028.[Abstract/Free Full Text]
  27. Coppoolse R, Rees W, Krech R, et al. Routine minimal invasive vein harvesting reduces postoperative morbidity in cardiac bypass proceduresclinical report of 1400 patients. Eur J Cardiothorac Surg 1999;16(Suppl 2):S61-S66.[Abstract/Free Full Text]
  28. Folliguet T, Severac-Bastide R, Le Bret E, et al. [Harvesting of an internal saphenous graft for aorto-coronary bypass using video-surgery] Arch Mal Coeur Vaiss 1999;92(7):859-866.[Medline]
  29. Hayward 3rd TZ, Hey LA, Newman LL, et al. Endoscopic versus open saphenous vein harvestthe effect on postoperative outcomes. Ann Thorac Surg 1999;68(6):2107-2110discussion 2110–1.[Abstract/Free Full Text]
  30. Kan CD, Luo CY, Yang YJ. Endoscopic saphenous vein harvest decreases leg wound complication in coronary artery bypass grafting patients J Card Surg 1999;14(3):157-162discussion 163.[Medline]
  31. Rodrigus IE, Stockman B, Amsel BJ, Moulijn AC. Should we use video-assisted endoscopic vein harvesting as a standard technique? Heart Surg Forum 2001;4(1):53-55.[Medline]
  32. Carpino PA, Khabbaz KR, Bojar RM, et al. Clinical benefits of endoscopic vein harvesting in patients with risk factors for saphenectomy wound infections undergoing coronary artery bypass grafting J Thorac Cardiovasc Surg 2000;119(1):69-75.[Abstract/Free Full Text]
  33. Marty B, von Segesser LK, Tozzi P, et al. Benefits of endoscopic vein harvesting World J Surg 2000;24(9):1104-1107discussion 1107–8.[Medline]
  34. Black EA, Guzik TJ, West NE, et al. Minimally invasive saphenous vein harvestingeffects on endothelial and smooth muscle function. Ann Thorac Surg 2001;71(5):1503-1507.[Abstract/Free Full Text]
  35. Dusterhoft V, Bauer M, Buz S, et al. Wound-healing disturbances after vein harvesting for CABGa randomized trial to compare the minimally invasive direct vision and traditional approaches. Ann Thorac Surg 2001;72(6):2038-2043.[Abstract/Free Full Text]
  36. Bitondo JM, Daggett WM, Torchiana DF, et al. Endoscopic versus open saphenous vein harvesta comparison of postoperative wound complications. Ann Thorac Surg 2002;73(2):523-528.[Abstract/Free Full Text]
  37. Lutz CW, Hillmann R, Lutter G, et al. Endoscopic vs conventional vein harvestingfirst results with a new, non-disposable system. Thorac Cardiovasc Surg 2001;49(6):321-327.[Medline]
  38. Patel AN, Hebeler RF, Hamman BL, et al. Prospective analysis of endoscopic vein harvesting Am J Surg 2001;182(6):716-719.[Medline]
  39. Schurr UP, Lachat ML, Reuthebuch O, et al. Endoscopic saphenous vein harvesting for CABG – a randomized, prospective trial Thorac Cardiovasc Surg 2002;50(3):160-163.[Medline]
  40. Kiaii B, Moon BC, Massel D, et al. A prospective randomized trial of endoscopic versus conventional harvesting of the saphenous vein in coronary artery bypass surgery J Thorac Cardiovasc Surg 2002;123(2):204-212.[Abstract/Free Full Text]
  41. Felisky CD, Paull DL, Hill ME, et al. Endoscopic greater saphenous vein harvesting reduces the morbidity of coronary artery bypass surgery Am J Surg 2002;183(5):576-579.[Medline]
  42. Allen KB, Heimansohn DA, Robison RJ, et al. Influence of endoscopic versus traditional saphenectomy on event-free survivalfive-year follow-up of a prospective randomized trial. Heart Surg Forum 2003;6(6):E143-E145.[Medline]
  43. Bonde P, Graham AN, MacGowan SW. Endoscopic vein harvestadvantages and limitations. Ann Thorac Surg 2004;77(6):2076-2082.[Abstract/Free Full Text]
  44. Nowicki M, Buczkowski P, Miskowiak B, et al. Immunocytochemical study on endothelial integrity of saphenous vein grafts harvested by minimally invasive surgery with the use of vascular mayo stripersa randomized controlled trial. Eur J Vasc Endovasc Surg 2004;27(3):244-250.[Medline]
  45. 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 saphenectomya prospective randomized trial. J Thorac Cardiovasc Surg 2004;127(5):1402-1407.[Abstract/Free Full Text]
  46. Tevaearai HT, Mueller XM, von Segesser LK. Minimally invasive harvest of the saphenous vein for coronary artery bypass grafting Ann Thorac Surg 1997;63(6 Suppl)S119–21.
  47. Black EA, Campbell RK, Channon KM, et al. Minimally invasive vein harvesting significantly reduces pain and wound morbidity Eur J Cardiothorac Surg 2002;22(3):381-386.[Abstract/Free Full Text]
  48. Yun KL, et al. Randomized trial of endoscopic versus open vein harvest for coronary artery bypass graftingsix-month patency rates. J Thorac Cardiovasc Surg 2005;129(3):496-503.[Abstract/Free Full Text]
  49. 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(3):823-828.



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