A recent study by Dr. O’Donoghue, published in Circulation, shows that early aspirin discontinuation with continued P2Y12 inhibitor monotherapy, after the percutaneous coronary intervention (PCI), was associated with a significant reduction in major bleeding compared to dual antiplatelet therapy. This study did not show a significant increase in major adverse cardiovascular events (MACE) after aspirin discontinuation in the participants.
Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor, following the percutaneous coronary intervention (PCI), has been associated with a decreased risk of MACE but an increased risk of bleeding complications. The addition of oral anticoagulation to this combination, in patients with a medical indication for anticoagulation therapy after PCI, would further increase these bleeding risks. To decrease these bleeding complications, there has been a growing tendency toward the use of P2Y12 inhibitor monotherapy post PCI in individuals with recent atherosclerotic events. The current meta-analysis of randomized trials evaluated the safety and efficacy of aspirin discontinuation 1 to 3 months post PCI with a continued P2Y12 inhibitor compared to conventional dual antiplatelet therapy.
The study included five trials and a total of 32,145 patients who underwent PCI due to either stable coronary artery disease (CAD) or acute coronary syndrome (ACS). The P2Y12 inhibitor agent that was used for monotherapy was either clopidogrel (16.5% cases) or prasugrel or ticagrelor (83.5% cases). Therapy with aspirin was discontinued at 1-3 months after the procedure. Bleeding complications and MACE affected 820 and 937 individuals, respectively. The study demonstrated that, compared to dual antiplatelet therapy, early discontinuation of aspirin in the background of P2Y12 inhibitor monotherapy was associated with a significant reduction (40%) in bleeding complications post PCI (Hazard Ratio (HR):0.60, 95% Confidence Interval (CI): 0.45-0.79, P<0.001). Interestingly, those who underwent PCI for an ACS experienced more benefit from this strategy, and the risk of bleeding decreased by 50% (HR:0.50, 95% CI:0.41-0.61). Also, early discontinuation did not appear to increase the risk of MACE (HR:0.88, 95% CI:0.77-1.02), myocardial infarction (HR:0.85, 95% CI:0.69-1.06), or death (HR:0.85, 95% CI:0.70-1.03).
As with any other study, there are some limitations that should be considered while interpreting the results of this study. First, the optimal P2Y12 inhibitor that can be used for the purpose of monotherapy after aspirin discontinuation remains disputed. Second, whether this P2Y12 inhibitor monotherapy should be continued beyond 12-15 months following the procedure is still unclear. And it remains an unanswered question whether aspirin can be stopped earlier than one to three months post PCI.
Finally, clinicians should consider the eligibility criteria of the included trials in this meta-analysis while considering this strategy for their post PCI patients.