Effect of Lesion Complexity and Clinical Risk Factors on the Efficacy and Safety of Dabigatran Dual Therapy Versus Warfarin Triple Therapy in Atrial Fibrillation After Percutaneous Coronary Intervention: A Subgroup Analysis From the REDUAL PCI Trial.

BACKGROUND: The REDUAL PCI trial (Evaluation of Dual Therapy With Dabigatran vs Triple Therapy With Warfarin in Patients With AF That Undergo a PCI With Stenting) demonstrated that, in patients with atrial fibrillation following percutaneous coronary intervention, bleeding risk was lower with dabigatran plus clopidogrel or ticagrelor (dual therapy) than warfarin plus clopidogrel or ticagrelor and aspirin (triple therapy). Dual therapy was noninferior for risk of thromboembolic events. Whether these results apply equally to patients at higher risk of ischemic events due to lesion complexity or clinical risk factors is unclear.

METHODS: The primary end point was time to first major or clinically relevant nonmajor bleeding event. The composite efficacy end point was death, thromboembolic event, or unplanned revascularization. Our prespecified subgroup analysis categorized patients by presence of procedural complexity and/or clinical complexity factors at baseline. A modified dual antiplatelet therapy score categorized patients according to degree of clinical risk.

RESULTS: Of 2725 patients, 43.1% had clinical complexity factors alone, 9.9% procedural factors alone, 10.0% both, and 37.0% neither. Risk of the primary bleeding end point was lower in both dabigatran dual therapy groups than warfarin triple therapy groups, regardless of procedural and/or clinical lesion complexity (interaction P values: 0.90 and 0.37, respectively). Importantly, a similar risk of the efficacy end point was observed between dabigatran dual and warfarin triple therapy, regardless of the presence of clinical or procedural complexity factors (interaction P values: 0.67 and 0.54, dabigatran 110 and 150 mg dual therapy, respectively). Similar benefit was seen for each dose of dabigatran dual therapy for bleeding events regardless of dual antiplatelet therapy score (interaction P values: 0.53 and 0.54, respectively), with similar risk of thromboembolic events (interaction P values: 0.20 and 0.08, respectively).

CONCLUSIONS: In patients with atrial fibrillation undergoing percutaneous coronary intervention, dabigatran 110 and 150 mg dual therapy reduced bleeding risk compared with warfarin triple therapy, with a similar risk of thromboembolic outcomes, irrespective of procedural and/or clinical complexity and modified dual antiplatelet therapy score. Registration: URL: https://clinicaltrials.gov/; Unique identifier: NCT02164864.