Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp t is estimated that approximately 5% of patients referred for percutaneous coronary intervention (PCI) have an indication for long-term oral anticoagulation (OAC), mainly because of atrial fibrillation (AF). 1-4 Current guidelines recommend bridging therapy (BT) with unfractionated heparin or low-molecular-weight heparin (LMWH) to cover the temporary discontinuation of OAC, if the risk of thromboembolism is considered high. 5 Neither randomized trials nor large prospective datasets, however, have compared different strategies to manage long-term OAC during PCI. Data from recent observational studies suggest that uninterrupted OAC (UAC) could replace heparin bridging in OAC patients undergoing PCI with favorable balance between bleeding and thrombotic complications. Performing PCI during therapeutic anticoagulation (international normalized ratio [INR] 2.0-3.0) is currently regarded as an alternative strategy. 6,7 Given these prerequisites, we decided to test the hypothesis that UAC would not increase periprocedural bleeding and thrombotic compli-I