Uninterrupted oral anticoagulation (OAC) therapy can be the preferred strategy in patients with atrial fibrillation at moderate to high risk of thromboembolism undergoing percutaneous coronary intervention (PCI). To evaluate the need for additional heparins in addition to therapeutic peri-PCI OAC, we assessed bleeding complications and major adverse cardiac and cerebrovascular events in 414 consecutive patients undergoing PCI during therapeutic (international normalized ratio 2 to 3.5) periprocedural OAC. Patients were divided into those with no (n = 196) and with (n = 218) additional use of periprocedural heparins. No differences in major adverse cardiac and cerebrovascular events (4.1% vs 3.2%, p = 0.79) or major bleeding (1.0% vs 3.7%, p = 0.11) were detected, but access site complications (5.1% vs 11.0%, p = 0.032) were less frequent in those without additional heparins. When adjusted for propensity score, patients with additional heparins had a higher risk of access site complications (odds ratio 2.6, 95% confidence interval 1.1 to 6.1, p = 0.022) without any increased risk of any other adverse event. Analysis of 1-to-1 propensity-matched pairs showed a significantly higher risk of access site complication in patients receiving additional AC (13.1% vs 5.7%, p = 0.049). In conclusion, therapeutic warfarin treatment seems to provide sufficient AC for PCI. Additional heparins are not needed and may increase access site complications.