Effect of 1-Month Dual Antiplatelet Therapy Followed by Clopidogrel vs 12-Month Dual Antiplatelet Therapy on Cardiovascular and Bleeding Events in Patients Receiving PCI: The STOPDAPT-2 Randomized Clinical Trial.

Importance: Very short mandatory dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with a drug-eluting stent may be an attractive option. Objective: To test the hypothesis of noninferiority of 1 month of DAPT compared with standard 12 months of DAPT for a composite end point of cardiovascular and bleeding events. Design, Setting, and Participants: Multicenter, open-label, randomized clinical trial enrolling 3045 patients who underwent PCI at 90 hospitals in Japan from December 2015 through December 2017. Final 1-year clinical follow-up was completed in January 2019. Interventions: Patients were randomized either to 1 month of DAPT followed by clopidogrel monotherapy (n=1523) or to 12 months of DAPT with aspirin and clopidogrel (n=1522). Main Outcomes and Measures: The primary end point was a composite of cardiovascular death, myocardial infarction (MI), ischemic or hemorrhagic stroke, definite stent thrombosis, or major or minor bleeding at 12 months, with a relative noninferiority margin of 50%. The major secondary cardiovascular end point was a composite of cardiovascular death, MI, ischemic or hemorrhagic stroke, or definite stent thrombosis and the major secondary bleeding end point was major or minor bleeding. Results: Among 3045 patients randomized, 36 withdrew consent; of 3009 remaining, 2974 (99%) completed the trial. One-month DAPT was both noninferior and superior to 12-month DAPT for the primary end point, occurring in 2.36% with 1-month DAPT and 3.70% with 12-month DAPT (absolute difference, -1.34% [95% CI, -2.57% to -0.11%]; hazard ratio [HR], 0.64 [95% CI, 0.42-0.98]), meeting criteria for noninferiority (P < .001) and for superiority (P = .04). The major secondary cardiovascular end point occurred in 1.96% with 1-month DAPT and 2.51% with 12-month DAPT (absolute difference, -0.55% [95% CI, -1.62% to 0.52%]; HR, 0.79 [95% CI, 0.49-1.29]), meeting criteria for noninferiority (P = .005) but not for superiority (P = .34). The major secondary bleeding end point occurred in 0.41% with 1-month DAPT and 1.54% with 12-month DAPT (absolute difference, -1.13% [95% CI, -1.84% to -0.42%]; HR, 0.26 [95% CI, 0.11-0.64]; P = .004 for superiority). Conclusions and Relevance: Among patients undergoing PCI, 1 month of DAPT followed by clopidogrel monotherapy, compared with 12 months of DAPT with aspirin and clopidogrel, resulted in a significantly lower rate of a composite of cardiovascular and bleeding events, meeting criteria for both noninferiority and superiority. These findings suggest that a shorter duration of DAPT may provide benefit, although given study limitations, additional research is needed in other populations. Trial Registration: ClinicalTrials.gov Identifier: NCT02619760.

Prediction of Thrombotic and Bleeding Events After Percutaneous Coronary Intervention: CREDO-Kyoto Thrombotic and Bleeding Risk Scores.

BACKGROUND: Prediction of thrombotic and bleeding risk is important to optimize antithrombotic therapy after percutaneous coronary intervention. METHODS AND RESULTS: We developed the prediction rules for thrombotic and bleeding events separately in Japanese patients. Derivation and validation cohorts consisted of 4778 patients from CREDO-Kyoto (Coronary Revascularization Demonstrating Outcome Study in Kyoto) registry cohort 2 and 4669 patients from RESET (Randomized Evaluation of Sirolimus-Eluting Versus Everolimus-Eluting Stent Trial) and NEXT (Nobori Biolimus-Eluting Versus Xience/Promus Everolimus-Eluting Stent Trial). Primary thrombotic and bleeding events were a composite of myocardial infarction, definite or probable stent thrombosis or ischemic stroke, and GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) moderate or severe bleeding. The prediction rule for thrombosis assigned 2 points for severe chronic kidney disease, atrial fibrillation, peripheral vascular disease, and anemia and 1 point for age ≥75 years, heart failure, diabetes mellitus, and chronic total occlusion. The prediction rule for bleeding assigned 2 points for thrombocytopenia, severe chronic kidney disease, peripheral vascular disease, and heart failure and 1 point for prior myocardial infarction, malignancy, and atrial fibrillation. In derivation and validation cohorts, area under the curve was 0.68 and 0.64, respectively, for thrombosis and 0.66 and 0.66, respectively, for bleeding. In the validation cohort, a high thrombosis risk score (≥4, n=682) was associated with higher 3-year incidence of thrombotic events than a score that was intermediate (2-3, n=1178) or low (0-1, n=2809) (7.6%, 3.7%, versus 2.4%, respectively; P<0.0001). A high bleeding risk score (≥3, n=666) was associated with higher incidence of bleeding than scores that were intermediate (1-2, n=1802) or low (0, n=2201) (8.8%, 4.1%, versus 2.3%, respectively; P<0.0001). Among 682 patients at high thrombotic risk, only 39 (5.7%) had low bleeding risk, whereas 401 (58.8%) had high bleeding risk with very high incidence of bleeding (11.6%). CONCLUSIONS: CREDO-Kyoto thrombotic and bleeding risk scores demonstrated modest accuracy in stratifying thrombotic and bleeding risks; however, a large proportion of patients at high thrombotic risk also had high bleeding risk.