Cardiac CAtheterization for Bypass Graft Patency Rate Optimization: the CABG-PRO Randomized-controlled Pilot Study

Aortocoronary bypass graft failure is common and is associated with high morbidity and
mortality. Failure of saphenous vein grafts is more common than failure of internal mammary
artery grafts. Whether early graft angiography can reduce bypass graft failure remains
unknown. The Cardiac CAtheterization for Bypass Graft Patency Rate Optimization (CABG-PRO)
randomized-controlled pilot study is a phase III, double-blind, randomized-controlled pilot
trial that will randomize 170 patients undergoing coronary artery bypass graft surgery to
early (before dismissal) graft angiography vs. no early graft angiography. Coronary
angiography will be performed at 12 months, to determine whether compared to no early graft
angiography, early graft angiography will result in:

1. lower per patient angiographic bypass graft failure (in at least one graft) rates
(defined as ≥75% diameter stenosis in at least one bypass graft) (primary efficacy
endpoint)

2. lower per graft failure rates, per graft occlusion rates, and per patient bypass graft
occlusion rates (in at least one bypass graft) (secondary endpoints)

3. lower incidence major adverse cardiac events (death, nonfatal myocardial infarction,
nonfatal stroke, coronary revascularization, and composite of death/myocardial
infarction) (secondary endpoint)

Intravascular ultrasonography and near-infrared spectroscopy will also be performed in at
least one bypass graft at baseline (in the early graft angiography group only) and at
12-month angiographic follow-up to evaluate the structural bypass graft changes occurring
after coronary artery bypass graft surgery (secondary endpoint).