To Örebro University

Objectives: Our objective was to evaluate the impact of vein graft harvesting technique on structure and function of vasa vasorum.

Methods: Paired segments of great saphenous veins harvested either with conventional harvesting technique or no-touch technique were obtained from 9 consecutive patients undergoing coronary artery bypass grafting. Quantitative measurements, using immunohistochemistry and morphometry, were performed. Ultrastructural analyses of vasa vasorum were performed with electron microscopy. Video footage of superficial vasa vasorum in an implanted saphenous vein graft harvested with the no-touch technique was captured during a coronary bypass operation and is presented for online viewing.

Results: The total area of vasa vasorum in vein grafts harvested with the conventional technique was significantly reduced both in the media (P¼.007) and in the adventitia (P¼.014) compared with vein grafts harvested with the no-touch technique. Ultrastructural findings indicated that the no-touch technique preserved an intact vasa vasorum whereas the conventional technique did not. Video footage showed retrograde flow in the vasa vasorum in vein graft harvested with the no-touch technique.

Conclusions: These findings showthat the no-touch technique for saphenous vein graft harvesting for coronary bypass grafting preserves an intact vasa vasorum. This could represent one of the mechanisms underlying the improved patency of saphenous vein grafts harvested with this technique.

No-touch (NT) saphenous vein (SV) grafts are superior to SVs harvested by the conventional technique (CT), with a patency comparable with the internal thoracic artery (ITA). Preservation of the vasa vasorum is implicated in the success of NT harvesting. We compared the vasa vasorum and endothelial nitric oxide synthase (eNOS) in NT SV with ITA and radial artery (RA) grafts. Skeletonized SV (SSV) was also analyzed. The NT SV had a higher number and larger vasa vasorum compared with ITA (P = .0001) and RA (P = .0004) that correlated with eNOS protein. Activity of eNOS in SSV grafts was significantly lower than NT SV grafts (P = 004). Since a high proportion of the vasa vasorum are removed in SSV using the CT, we suggest that preservation of the vasa vasorum and eNOS-derived NO contributes to the high patency for NT as compared with SSV grafts.

Background: Injury incurred while saphenous veins are being obtained results in poor graft patency and impairs the results of coronary artery bypass grafting. A novel method of obtaining veins, the no-touch technique, has shown improved long-term saphenous vein graft patency.

Methods: This randomized trial included 108 patients undergoing coronary artery bypass grafting and compared the patency of no-touch saphenous vein with that of radial artery grafts. Each patient was assigned to receive one no-touch saphenous vein and one radial artery graft to either the left or the right coronary territory to complement the left internal thoracic artery.

Results: Angiography was performed in 99 patients (92%) at a mean of 36 months postoperatively. Graft and grafted coronary artery patency was evaluated. The patency of grafts for no-touch saphenous vein and radial artery was 94% versus 82% (p = 0.01), respectively. The patency of coronary arteries grafted with no-touch saphenous vein and radial artery grafts was 95% versus 84% (p = 0.005), respectively. Eighty-nine of 96 (93%) left internal thoracic artery grafts were patent.

Conclusions: No-touch saphenous vein grafts showed a significantly higher patency rate than the radial artery grafts and the patency was comparable to the patency for left internal thoracic artery grafts. This highlights the improvement in saphenous vein graft quality with the no-touch technique and increases the number of situations in which saphenous veins may be preferable to radial artery grafts as conduits in coronary artery bypass grafting.

Background The left internal thoracic artery (LITA) is the gold standard conduit for grafting of the left anterior descending (LAD) coronary artery in coronary artery bypass grafting (CABG) surgery due to superior long-term patency rates and evidence of improved long-term outcomes. The LITA grafts are traditionally harvested with a pedicle of surrounding tissue (PLITA). Alternatively the LITA can be harvested in a skeletonized fashion (S-LITA) where the graft is being dissected from all surrounding tissues. Advocates of skeletonization postulate that this technique reduces sternal devascularisation, the incidence of chest wall pain and dysesthesia, wound healing problems, and increase the number of arterial anastomoses per patient by increasing the length of the LITA. To our knowledge this is the first randomised trial comparing angiographic mid-term patency rates between skeletonized andpedicled ITAs.

Methods This randomized trial included 109 patients undergoing coronary artery bypass grafting surgery and compared the patency for P-LITA and S-LITA. The patients were assigned to receive either one P-LITA or one S-LITA to the LAD. Complementary grafting was performed using both No-touch saphenous vein and radial artery grafts.

Results Graft patency was evaluated with angiography in 100 patients (92 %) at mean 36 months postoperatively. The patency rate for P-LITA (46/48, 96 %) did not differ (p=0.44) compared to S-LITA (47/52, 90 %). All failed grafts, except one with a localised stenosis, (S-LITA) were connected to LAD coronary arteries with a stenosis less than 70%.

Conclusions The evidence presented here demonstrates that in terms of patency, both P-LITA and S-LITA provide excellent results. It seemed that the most important factor for ITA occlusion was the degree of stenosis of the LAD and not the technique used for their preparation.

Clinical Trial registration 

NCT01310725 ClinicalTrials.gov [http://clinicaltrials.gov/ct2/show/NCT01310725]