• Graft occlusion determined by conventional angiography or CT angiography [ Time Frame: 4 days to 4 months following surgery ] [ Designated as safety issue: No ]
  

• 50-99% graft stenosis on postoperative graft angiography [ Time Frame: 4 day to 4 months postoperatively ] [ Designated as safety issue: No ]
  
• Mortality, myocardial infarction, low output syndrome [ Time Frame: Perioperatively ] [ Designated as safety issue: No ]
  
• Major cardiac adverse events [ Time Frame: 1 year postoperatively ] [ Designated as safety issue: No ]
  

The immediate and long term success of coronary surgery is dependent on the construction of a high quality anastomosis with a durable conduit to an appropriate target coronary vessel. Significant advances in medical therapy including early post-operative aspirin administration and increased use of arterial grafting have improved early, midterm and late graft patency. However, modern coronary bypass series continue to report perioperative graft occlusions rates as high as 11%. These very early graft failures have been predominantly ascribed to technical problems at graft anastomosis sites and may be preventable. New intraoperative graft assessment technologies have recently become available which can identify technical problems such that they can be repaired in the operating room. However, these techniques increase the length of the bypass operation and may have false positives, which may lead to unnecessary and potentially damaging graft revisions. The primary objective of the proposed study is to determine if a strategy of intraoperative patency assessment and graft revision can decrease the rate of graft occlusion or significant stenosis(>50%) at 6-12 weeks after coronary artery bypass grafting (CABG) versus traditional operative management without routine intraoperative patency assessment.