Incidence of complications of antithrombotic treatment in patients with atrial fibrillation
Introduction. Atrial fibrillation increases the risk of ischemic stroke five fold, while the application of long-term anticoagulant therapy is associated with the occurrence of hemorrhagic complications. The aim of our study was to evaluate the incidence of thrombotic and hemorrhagic complications in patients with atrial fibrillation during antithrombotic treatment. Material and Methods. The study included 504 patients that were administered the primary (n=345) or secondary thromboprophylaxis after ischemic stroke (n=159), by applying vitamin K antagonists, or the combination of vitamin K antagonists and low-dose aspirin. The patients were followed for five months in the period of 24 years from 1988 to 2012, the total number of patient?s years being 1884, at the Clinical Center of Vojvodina. Thromboembolic and hemorrhagic complications were registered during regular check-up examinations. Results and Discussion. Our results indicate the low incidence of thromboembolic complications (0.01 patient per a year), with a lower incidence in the vitamin K antagonists group than in the group with the combination of vitamin K antagonists and aspirin (0.008 patient per a year versus 0.01 patient per a year). The incidence of hemorrhagic complications was higher in the group with the combined treatment compared to the group treated with vitamin K antagonists (0.1 patient per a year versus 0.06 patient per a year). The frequency of major bleeding was as low as 0.01 patient per a year and more frequent in the group with combined treatment (0.03 patient per a year). Conclusion. The overall incidence of complications in the study group was 0.08 patient per a year. The combined antithrombotic treatment increases the risk of hemorrhagic complications and affects the severity of bleeding. Oral anticoagulant therapy is more efficient in the prevention of ischemic stroke and thromboembolic complications in patients with atrial fibrillation.