Veingraftthrombosis is the leading cause of acute graft failure within the first post-operative month. Several studies have shown the benefit of post-operative dual anti-platelet therapy (DAPT) in preventing acute graftthrombosis. The purpose of this study was to determine whether peri-operative initiation of DAPT will improve short and intermediate term graft patency.
Methods:
This was a randomized, double-blind, placebo controlled trial of 20 patients undergoing CABG to compare DAPT versus aspirin monotherapy. The primary outcome was post-operative graft patency at 2 and 52 weeks determined by <50% bypass graftstenosis by cardiac computed tomography angiography (CCTA). The secondary outcomes were (1) major adverse cardiovascular events (MACE), defined as myocardial infarction, thrombotic events, and angina, and (2) safety end-points defined as TIMI major and minorbleeding events.
Results:
The study population consisted predominately of men (19/20 patients). At 2 weeks, all LIMA grafts were patent although veingraft patency for the DAPT group was only 83.3% (20/24) compared to 89.5% (17/19) for placebo (p=0.597). At 52 weeks, the patency rate in the placebo group was 52.6% (10/19) as compared to a patency of 71.4% (15/24) in the dual anti-platelet therapyarm (p=0.244).
Conclusion:
The addition of clopidogrel to aspirin post-bypass surgery did not significantly improve venous graft patency at 2 weeks but trended toward higher graft patency at 52 weeks.