March 11, 2017Open Access
View Full PaperImpact of dual antiplatelet therapy after coronary artery bypass surgery on 1-year outcomes in the Arterial Revascularization Trial†
Key Result
Dual antiplatelet therapy with clopidogrel at discharge following CABG did not significantly reduce 1-year MACCE compared to aspirin alone (5.6% vs 5.6%; HR 0.97; 95% CI 0.59-1.59; P=0.90).
Study Design
Type
Observational (n=3,102)
Structured PICO
Does DAPT with clopidogrel reduce major adverse cerebrovascular and cardiac events at 1 year in patients following CABG compared to aspirin alone?
P
Population
3,102 patients enrolled in the Arterial Revascularization Trial (ART) who underwent coronary artery bypass grafting (CABG)
I
Intervention
Dual antiplatelet therapy (DAPT) with clopidogrel prescribed at discharge
C
Comparator
Aspirin alone prescribed at discharge
O
Outcome
Incidence of major adverse cerebrovascular and cardiac events (MACCE) at 1 year including cardiac death, myocardial infarction, cerebrovascular accident and reinterventioncomposite
Routine prescription of DAPT with clopidogrel at discharge following CABG does not significantly reduce 1-year adverse cardiovascular events compared to aspirin alone.
Main Result
Effect estimate: HR 0.97 (95% CI 0.59-1.59)
Absolute Event Rate: 5.6% vs 5.6%
p-value: p=0.90
Limitations
- Only 31% of subjects completed 1 year of DAPT
Abstract
OBJECTIVES: There is still little evidence to boldport routine dual antiplatelet therapy (DAPT) with P2Y12 antagonists following coronary artery bypass grafting (CABG). The Arterial Revascularization Trial (ART) was designed to compare 10-year survival after bilateral versus single internal thoracic artery grafting. We aimed to get insights into the effect of DAPT (with clopidogrel) following CABG on 1-year outcomes by performing a post hoc ART analysis. METHODS: Among patients enrolled in the ART (n = 3102), 609 (21%) and 2308 (79%) were discharged on DAPT or aspirin alone, respectively. The primary end-point was the incidence of major adverse cerebrovascular and cardiac events (MACCE) at 1 year including cardiac death, myocardial infarction, cerebrovascular accident and reintervention; safety end-point was bleeding requiring hospitalization. Propensity score (PS) matching was used to create comparable groups. RESULTS: Among 609 PS-matched pairs, MACCE occurred in 34 (5.6%) and 34 (5.6%) in the DAPT and aspirin alone groups, respectively, with no significant difference between the 2 groups hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.59-1.59; P = 0.90. Only 188 (31%) subjects completed 1 year of DAPT, and in this subgroup, MACCE rate was 5.8% (HR 1.11, 95% CI 0.53-2.30; P = 0.78). In the overall sample, bleeding rate was higher in DAPT group (2.3% vs 1.1%; P = 0.02), although this difference was no longer significant after matching (2.3% vs 1.8%; P = 0.54). CONCLUSIONS: Based on these findings, when compared with aspirin alone, DAPT with clopidogrel prescribed at discharge was not associated with a significant reduction of adverse cardiac and cerebrovascular events at 1 year following CABG.