Oral anticoagulant therapy during and after coronary angioplasty - The intensity and duration of anticoagulation are essential to reduce thrombotic complications

Background-In the randomized Balloon Angioplasty and Anticoagulation Study (BAAS), the addition of oral anticoagulants to aspirin significantly reduce d early and late events after coronary angioplasty. However, bleeding episo des were increased, The present report studied the intensity and the durati on of anticoagulation as predictors of thrombotic and bleeding events. Methods and Results-A, total of 530 patients, 34% of whom received a stent, were treated with aspirin plus coumarins. Half of the patients were random ized to angiographic follow-up. The target international normalized ratio ( INR) was 2.1 to 4.8 during angioplasty and 6-month follow-up. Thrombotic ev ents were death, myocardial infarction, target lesion revascularization, an d thrombotic stroke. Bleeding complications were hemorrhagic stroke, major extracranial bleeding, and false aneurysm. "Optimal" anticoagulation was de fined as an INR in the target range for at least 70% of the follow-up time. There were 17 early thrombotic events (3.2%), 7 early bleeding episodes (1 .3%) and 10 false aneurysms (1.9%). The incidence rate for both early throm botic and bleeding events was lowest in patients in the target range. A tot al of 61 late thrombotic events occurred (11.6%). Optimal anticoagulation w as an independent predictor of late thrombotic events (relative risk, 0.33; 95% CI, 0.19 to 0.57) and was associated with a 0.21 mm (95% CI, 0.17 to 0 .42) larger vessel lumen at 6 months. Late bleeding episodes (1.4%) were lo west in patients in the target range. Conclusions-Coumarins started before coronary angioplasty with a target INR of 2.1 to 4.8 led to the lowest procedural event rate, without an increase in bleeding episodes. During follow-up, optimal anticoagulation was associ ated with a decrease in the incidence of late events by 67% and a significa nt improvement in 6-month angiographic outcome.