Coronary artery bypass grafting (CABG) is a surgery to create a new path for blood flow to the heart. A healthy section of vein or artery from elsewhere in the patient's body will be attached to the coronary artery just above and below the area of concern, to create a way for blood to bypass the blocked part of the coronary artery.

The incidence and severity of strokes experienced between the groups will be assessed at 30 days and at one year after the index procedure, using the NIH Stroke Scale (NIHSS). The NIHSS is a 15-item neurologic examination stroke scale used to evaluate the effect of acute cerebral infarction on the levels of consciousness, language, neglect, visual-field loss, extraocular movement, motor strength, ataxia, dysarthria, and sensory loss. A trained observer rates the patent's ability to answer questions and perform activities. Ratings for each item are scored with 3 to 5 grades with 0 as normal, and there is an allowance for untestable items. The single patient assessment requires less than 10 minutes to complete.

The incidence of ischemia-driven revascularization experienced between the groups will be assessed at 30 days and at one year after the index procedure.

The amount of time each patient spends on a ventilator during the index hospitalization will be collected.

The incidence of re-exploration due to postoperative bleeding will be collected during the index hospitalization.

Chest tube drainage complications will be collected during the index hospitalization.

Hospital length of stay will be collected during the index hospitalization.

The incidence of wound infection will be collected during the index hospitalization.

The incidence of atrial fibrillation will be collected during the index hospitalization.

The incidence of blood transfusions will be collected during the index hospitalization.

Hospital readmission (all-cause and cardiac) will be assessed at 30 days and at one year after the index procedure.

Angina will be assessed at Baseline (prior to surgery), 30 days after the procedure, and at one year after the index procedure.

The Canadian Cardiovascular Society Angina Grading Scale will be used to categorize angina:

• Class I - Ordinary physical activity does not cause angina, such as walking and climbing stairs. Angina with strenuous or rapid or prolonged exertion at work or recreation
• Class II - Slight limitation of ordinary activity. Walking or climbing stairs rapidly, walking uphill, walking or stair climbing after meals, or in cold, or in wind, or under emotional stress or only during the few hours after awakening
• Class III - Marked limitation of ordinary physical activity. Walking one or two blocks on the level and climbing one flight of stairs in normal conditions and at normal pace
• Class IV - Inability to carry on a physical activity without discomfort - angina syndrome may be present at rest

The Duke Activity Scale Index (DASI) will be administered at Baseline (prior to surgery), 30 days after the procedure, and at one year after the index procedure. The DASI is a 12 item survey that asks about a patient's functional capacity in order to estimate peak oxygen uptake. Respondents answer "yes" or "no" to questions about their ability to do activities of different intensity levels.

The EuroQol EQ-5D will be administered at Baseline (prior to surgery), 30 days after the procedure, and at one year after the index procedure. The EuroQol EQ-5D is a 6 item survey that asks about how a patient is feeling on the day of the survey in terms of mobility, self-care, usual activities, pain/discomfort, anxiety/depression, and how they rate their health on a scale of 0 to 100 (where 0 is the worst health imaginable and 100 is the best health imaginable).