Abstract 9598: Off-Pump Coronary Artery Bypass Surgery is Associated with Worse Arterial and Saphenous Vein Graft Patency and Less Effective Revascularization in All Coronary Territories: Results From the Veterans Affairs Randomized On/Off Bypass Trial

Abstract

Background: From February 2002 to May 2007, the Randomized On/Off Bypass (ROOBY) Trial randomized 2,203 patients to off-pump vs. on-pump CABG. ROOBY hypothesized that there would be no difference between treatments in 1-year arterial conduit patency, SVG patency, and/or effective revascularization (ER). Methods: Angiography was obtained in 685 (62%) off-pump and 685 (62%) on-pump patients. A blinded angiographic core lab assessed angiograms for FitzGibbon's patency class (A = widely patent, B = flow limiting, O = occluded) and ER (defined as the major diseased coronary artery within each major coronary territory was revascularized by a FitzGibbon class A graft with no new stenosis distal to the graft anastamosis). Angiographic findings were compared for off-pump versus on-pump using appropriate statistical tests. Results: There were no differences in baseline patient characteristics between arms. FitzGibbon class A patency rates were significantly worse off-pump than on-pump for arterial conduits (85.8% vs. 91.4%, p = 0.003) and SVGs (72.7 vs. 80.4%, p < 0.001). Fewer off-pump patients had ER to all diseased territories (50.1% vs. 63.9% on-pump, p < 0.001). Each major coronary territory had worse ER off-pump than on-pump (see table). The 1-year composite adverse event rate (death, non-fatal MI or repeat revascularization) was 16.4% in patients with ineffective revascularization vs. 5.9% in patients with ER to all 3 coronary territories (p <0.01). Conclusion: Off-pump CABG resulted in significantly worse FitzGibbon patency for arterial and SVG conduits and less effective revascularization than on-pump CABG. Overall, patients with less effective revascularization had more 1-year adverse events.