Introduction. Dual antiplatelet therapy lasting 12 months is currently recommended for all patients with acute coronary syndrome. As life expectancy increases, the number of patients in advanced age with acute coronary syndromes and comorbidities with high thrombo-embolic risk (such as atrial fibrillation, venous thrombotic disease, valvular diseases) is also increasing. That is why the need for simultaneous administration of dual antiplatelet and oral anticoagulant therapy (triple therapy) has become more common recently. Because of the lack of large randomized trials regarding triple therapy, the scale of the problem in Poland is unknown. Aims. To assess the number of patients requiring oral anticoagulation among those hospitalized with acute coronary syndrome in everyday medical practice, to define the reasons of not administering such therapy and to assess the presence of cardiovascular risk factors, prognostic risk factors of bleeding and in-hospital complications in these patients. Methods. Retrospective analysis included 2279 patients diagnosed with acute coronary syndrome who were admitted to the Departments of Cardiology in Cracow in 2008. Patients were divided into three subgroups depending on the treatment: 1/ with prescribed triple therapy; 2/ with recommendation of usage of ASA, derivative of thienopyridine and oral anticoagulant; 3/ treated with other combinations of antiplatelet and anticoagulant drugs. Analysis of presence of cardiovascular risk factors, comorbidities, risk factors for bleeding according to GRACE registry and recommended treatment was conducted during hospitalization and upon discharge from hospital. Results. Among 2279 patients diagnosed with ACS, 365 (16.02%) had indications for long-term anticoagulation. The largest group consisted of patients with unstable angina who were treated pharmacologically (30.68%). The most common indication for chronic anticoagulation was paroxysmal atrial fibrillation (59.72%). Among patients with atrial fibrillation the average CHADS2 score was 2.49. In patients requiring triple therapy average age was 73.2 years, hypertension was diagnosed in 79.73%, hyperlipidemia in 63.01% and prognostic factors for bleeding were quite common. Only 11.5% patients received triple therapy at discharge from hospital. Most of them did not have INR on the therapeutic level. In 25.21% the recommended time of usage of dual antiplatelet therapy was not given. The cause of not administrating triple therapy was not clear in most of the patients, and among those with defined reason of rejecting the proper treatment - anticipated poor compliance (13.93%) and planned coronarography, coronary angioplasty or surgery (12.07%) were most common. Most of the patients receiving triple therapy were men and were younger than other patients. They more often gave a history of PCI or CABG and more often were treated with PCI. Among them there were no patients with bleeding during hospitalization. Anemia (p = 0.027, OR = 2.56) and age greater than 75 years (p= 0.037; OR 2.26) were significantly associated with withdrawal of triple therapy. Conclusions. 1. Patients requiring oral anticoagulation comprise significant percentage (16%) of those hospitalized with acute coronary syndrome. 2. The usage of combined treatment with dual antiplatelet therapy and oral anticoagulation in patients with acute coronary syndrome and indications for this therapy is insufficient. 3. The reasons for not prescribing triple therapy are not clear. The most important reason is the concern for hemorrhagic complications and noncompliance between patient and doctor. 4. Patients requiring triple therapy have more often a history of comorbidities, cardiovascular risk factors and prognostic risk factors of bleeding when compared with the unselected group of patients with acute coronary syndrome. 5. Anemia and age greater than 75 years are connected with not administrating triple therapy.