Aspirin after CABG has never been controversial. The controversy has always been: should we add a P2Y12 inhibitor, creating dual antiplatelet therapy (DAPT), to keep grafts open and prevent ischemic events?
Part of the reason this debate matters is sobering. Despite our best surgical techniques, vein graft attrition is common. An article from Circulation in 2011 (Circulation. 2011;124:273–283) reported that 10–20% of saphenous vein grafts occlude within the first year, and by 10 years, nearly 50% are closed. Arterial grafts (particularly LIMA to LAD) remain durable, but the average CABG patient receives 2–3 vein grafts — and these remain the Achilles’ heel of long-term outcomes.
So the hope has always been that “more potent” platelet inhibition might preserve graft patency and improve survival. At ESC 2025, two major RCTs TACSI and TOP-CABG gave us the most CABG specific data yet. And the answers are more about restraint than escalation.
TACSI (NEJM 2025)
| Feature | Details |
|---|---|
| Design | 2,200 ACS patients undergoing CABG randomized to ticagrelor + aspirin vs aspirin alone |
| Follow-up | 1 year |
| Primary Endpoint | Death, MI, stroke, or repeat revascularization |
| Results | No significant difference: 4.8% (DAPT) vs 4.6% (aspirin) |
| Bleeding | Major bleeding: 5% (DAPT) vs 2% (aspirin) |
| Net clinical outcome | 9% (DAPT) vs 6% (aspirin) — worse with DAPT |
Key nuance: TACSI showed no ischemic benefit but a clear bleeding hazard. Routine prolonged DAPT after CABG, even in ACS patients, is not justified. Note that 20% of patients stopped ticagrelor at 1 month, and 40% stopped it within a year.
TOP-CABG (ESC 2025)
| Feature | Details |
|---|---|
| Design | 2,000 post-CABG patients randomized to 12 months of DAPT vs 3 months of DAPT followed by aspirin monotherapy |
| Follow-up | 1 year |
| Primary Endpoint | Graft occlusion |
| Results | Similar graft occlusion rates: 10.8% (full DAPT) vs 11.2% (de-escalated) |
| Bleeding | Clinically relevant bleeding: 13.2% (full DAPT) vs 8.3% (de-escalated) |
Key nuance: De-escalated therapy (3 months of DAPT → aspirin alone) preserved graft patency while significantly reducing bleeding.
CURE and CABG Patients
The CURE trial (2001) randomized >12,000 ACS patients to clopidogrel + aspirin vs aspirin. In the subgroup that went on to CABG, there was a trend toward fewer ischemic events with DAPT, but bleeding risk was higher, especially when clopidogrel was not held pre-op. It wasn’t definitive, but it fueled two decades of speculation: could DAPT be the solution to vein graft attrition?
Why the Different Messages?
- Population & framing:
- TACSI asked: Should everyone get prolonged DAPT post-CABG? → No.
- TOP-CABG asked: Can short DAPT be enough to protect grafts? → Yes.
- Endpoints:
- TACSI: composite of death/MI/stroke/revasc → neutral.
- TOP-CABG: graft patency → preserved with de-escalation.
- Bleeding:
- Both showed the obvious: the longer you stay on DAPT, the more bleeding you get.
Practical Pearls
- Aspirin is the foundation; DAPT is not routine post-CABG.
- Routine 12-month DAPT in ACS CABG patients (per TACSI) = no benefit, more bleeding.
- A de-escalation approach (3 months of DAPT, then aspirin) seems safe for grafts and reduces bleeding (TOP-CABG).
- Graft patency is a real issue with up to 20% lost in the first year and 50% by 10 years, adding antiplatelet therapy may attenuate this, but comes at the cost of increased risk of bleeding.
My Take
TACSI and TOP-CABG give us the clearest RCT data yet for CABG patients, filling a gap that CURE only hinted at. The results align with what many suspected: DAPT may help improve graft patency, but is countered by a real increase in bleeding risk.
That said, one should also note that in TACSI, graft patency was not directly measured, though the results of the CoCAP trial will help delineate this further (it’s a coronary CT sub-study from TACSI data).
The future likely lies in better surgical conduit selection, aggressive risk factor control, and possibly targeted antiplatelet strategies (short DAPT windows, or new agents yet to be tested). Personally, when looking at DAPT post-CABG, I think this reinforces clopidogrel as a reasonable option, given that you still get a P2Y12 inhibition benefit, with reduced bleeding risk (compared to ticagrelor).
TLDR:
- TACSI (2025): DAPT vs aspirin → no ischemic benefit, more bleeding.
- TOP-CABG (2025): De-escalated DAPT (3 months → aspirin) = same graft patency, less bleeding.
- CURE (2001): Early hint of DAPT improving graft patency
- Context: 10–20% of vein grafts close in the first year, ~50% by 10 years.
- Clinical message: DAPT can help, but be careful with the increased bleeding risk
