Assessing Vein Graft Properties Between Conventional & No-Touch Harvesting Technique - (PATENT SVG)

Comparative Evaluation of Vasomotor Function in Saphenous Veins Harvested Using Pedicled vs Conventional Technique

The purpose of this study is to compare saphenous veins harvested using the atraumatic pedicled ("no-touch") technique to saphenous veins harvested using the conventional open technique in patients undergoing isolated coronary artery bypass surgery. Investigators will compare the biological structure of the saphenous veins harvested using these two techniques. There is some evidence that saphenous veins harvested using the "no-touch" technique may allow for better patency up to 8 years following bypass surgery. We may be able to detect early differences in vascular structure, observed at the time of conduit harvest.

Atherosclerosis is a complex, multifactorial inflammatory disease, which is initiated largely in areas of endothelial injury, secondary to biomechanical disturbances, or systemic factors such as lipoprotein disturbances, hypertension, diabetes, and smoking (the response to injury hypothesis). Accumulating data indicate that structural and/or functional alterations in endothelial integrity play a primordial role in the development of atherosclerosis via promoting aberrant interactions between modified lipoproteins, monocyte-derived macrophages, T cells and normal cellular elements of the arterial wall inciting early plaque formation. As such, strategies, either pharmacological or mechanical in nature which reduce and/or restore endothelial homeostasis remain an important cornerstone to limit atherosclerosis.

Investigators hypothesize that saphenous veins harvested using the atraumatic pedicled ("no-touch") technique from patients undergoing isolated coronary artery bypass surgery will exhibit superior indices of vasomotor structure compared to veins harvested using the conventional open technique. We anticipate that leg healing will not be significantly altered using the "no-touch" technique.

Eligible patients will have two SVG segments harvested, one from each lower leg. One leg will have the SVG harvested in the conventional fashion and the contralateral leg will have the SVG harvested using the "no touch" technique. This will be determined by block randomization revealed at the time of skin incision. For patients with very small lower leg saphenous veins, the surgical protocol would be to then use the thigh segment instead. Patients will have Duplex scans to evaluate saphenous veins pre-operatively.

Inclusion Criteria:

1. Age> 18 years and able to provide informed consent
2. Requiring isolated, primary coronary artery bypass graft surgery
3. Elective or urgent cases
4. With or without the use or cardiopulmonary bypass
5. Left ventricular ejection fraction > 20%
6. Patient require at least 2 SVG's

Exclusion Criteria:

1. Unable to give consent
2. Unable to use bilateral lower greater saphenous veins ( severe peripheral vascular disease,varicose veins, previous vein stripping, previous amputation, inadequate ultrasound appearance )
3. Pregnant women, women of child bearing age
4. Preoperative persistent atrial fibrillation