Recommendations for Duration of DAPT in Patients Undergoing CABG
Aspirin therapy after CABG (coronary artery bypass grafting) improves vein graft patency, particularly during the first postoperative year, and reduces MACE (major adverse cardiac events). In the CURE study, the reduction in ischemic events in patients treated with aspirin plus clopidogrel who underwent CABG was consistent with the study population as a whole, although benefit was primarily observed mainly before the procedure. A propensity score analysis of a Danish administrative database demonstrated during a mean follow-up of 466 ± 144 days significantly fewer deaths in patients treated with aspirin plus clopidogrel than in those treated with aspirin alone, although there was no reduction in the incidence of recurrent MI.
The impact of clopidogrel on graft occlusion after on-pump CABG has been evaluated in 5 studies. Several randomized and nonrandomized trials and a post hoc substudy analysis of patients predominantly undergoing on-pump CABG did not demonstrate any differences in graft patency between antiplatelet monotherapy and DAPT when assessed at follow-up ranging from 1 month to 1 year after CABG. In the only RCT to demonstrate a benefit of DAPT, vein graft patency 3 months after CABG was significantly higher in patients treated with clopidogrel and aspirin (100 mg) than in those receiving aspirin monotherapy.
Two meta-analyses and 1 systematic overview assessed the potential benefits of DAPT after CABG and reported mixed results. In the largest meta-analysis of patients pooled from 5 RCTs and 6 observational studies, DAPT was associated with reduced vein graft occlusion and 30-day mortality rate as compared with aspirin monotherapy. A meta-analysis of only the 5 RCTs showed that DAPT was associated with a significantly lower vein graft occlusion at 1 year versus antiplatelet monotherapy but with no improvement in arterial graft patency. Major bleeding after surgery was more frequent with DAPT .
The benefits of DAPT in off-pump CABG patients were noted in terms of improved graft patency and clinical outcome in single-center observational studies and an RCT.
Only data from post hoc analyses are available on the utility of newer P2Y12 inhibitors in patients with ACS who undergo CABG. In a retrospective analysis of patients in the TRITON-TIMI 38 study who underwent CABG, prasugrel treatment was associated with a significantly lower 30-day mortality rate than that of clopidogrel and more postoperative blood loss. A post hoc analysis of patients who underwent CABG in the PLATO study showed that the primary endpoint at 1 year was similar for both treatments, but a significant reduction in cardiovascular mortality was noted with ticagrelor compared with clopidogrel .
Issues related to the timing of discontinuation of DAPT before CABG are beyond the scope of this update but are addressed in the 2011 CABG guideline .
The impact of clopidogrel on graft occlusion after on-pump CABG has been evaluated in 5 studies. Several randomized and nonrandomized trials and a post hoc substudy analysis of patients predominantly undergoing on-pump CABG did not demonstrate any differences in graft patency between antiplatelet monotherapy and DAPT when assessed at follow-up ranging from 1 month to 1 year after CABG. In the only RCT to demonstrate a benefit of DAPT, vein graft patency 3 months after CABG was significantly higher in patients treated with clopidogrel and aspirin (100 mg) than in those receiving aspirin monotherapy.
Two meta-analyses and 1 systematic overview assessed the potential benefits of DAPT after CABG and reported mixed results. In the largest meta-analysis of patients pooled from 5 RCTs and 6 observational studies, DAPT was associated with reduced vein graft occlusion and 30-day mortality rate as compared with aspirin monotherapy. A meta-analysis of only the 5 RCTs showed that DAPT was associated with a significantly lower vein graft occlusion at 1 year versus antiplatelet monotherapy but with no improvement in arterial graft patency. Major bleeding after surgery was more frequent with DAPT .
The benefits of DAPT in off-pump CABG patients were noted in terms of improved graft patency and clinical outcome in single-center observational studies and an RCT.
Only data from post hoc analyses are available on the utility of newer P2Y12 inhibitors in patients with ACS who undergo CABG. In a retrospective analysis of patients in the TRITON-TIMI 38 study who underwent CABG, prasugrel treatment was associated with a significantly lower 30-day mortality rate than that of clopidogrel and more postoperative blood loss. A post hoc analysis of patients who underwent CABG in the PLATO study showed that the primary endpoint at 1 year was similar for both treatments, but a significant reduction in cardiovascular mortality was noted with ticagrelor compared with clopidogrel .
Issues related to the timing of discontinuation of DAPT before CABG are beyond the scope of this update but are addressed in the 2011 CABG guideline .
