Introduction
The saphenous vein (SV)continues to be a very important conduit in coronary artery bypass grafting (CABG) 1. Therefore, every effort should be made to improve the short and long-term patency of SV grafts (SVGs). The no-touch (NT) SVG harvesting technique was introduced in the 1990s. The NT SVG is harvested together with its fat pedicle preventing spasm and the need for manual dilatation2. A randomized study comparing the NT to the conventional vein harvesting technique, showed significantly higher patency for NT SVGs comparable to that of the left internal thoracic artery (LITA) 16 years postoperatively 3-5. Coronary artery bypass grafting is commonly performed with the support of cardiopulmonary bypass (CPB), so called on-pump procedure. Perioperative mortality is about 2% and the rate of myocardial infarction, stroke or renal failure requiring dialysis is 5-7% 6. The technique of performing CABG without CPB, off-pump surgery, was developed to reduce these perioperative complications7.
The CABG Off or On-pump Revascularization study (CORONARY trial, NCT00463294) is a large international multicenter randomized controlled trial. It was designed to overcome some of the limitations of prior trials 8. Our department was one of the including centers. The 30-days, one year and five-year results have been published6, 9. Graft patency was not evaluated in this study despite being a major determinant of clinical prognosis, measured by reoperation rates and long-term survival 10.Therefore, the aim of this sub-study is to assess graft patency in on- vs off-pump CABG in the cohort of patients operated at our department, especially considering that all vein grafts were harvested with the NT technique. Graft patency according to the different target coronary arteries was also studied.