With the aim of quantifying the use of oral anticoagulant (OA) therapy in clinical practice, we surveyed 150 consecutive patients admitted with a diagnosis of atrial fibrillation (AF). Each patient was administered a questionnaire relating to the classic vascular risk factors and to the antithrombotic treatment received at home. The diagnosis of AF was formulated at the time of admission in 45 cases. Of the 105 cases with a previous diagnosis, OA therapy was relatively or absolutely contraindicated in 21 patients (20%), whereas the other 84 (80%) were ideal candidates for the treatment. Of these, 20 (24%) were actually receiving OA, 16 (19%) were on platelet anti-aggregants (PA), and 48 (57%) were receiving no antithrombotic treatment at all. Even lower percentages of OA use were found in the patients with a previous (20%) or recent (16%) history of cerebral ischemia. Upon discharge, of the 115 patients without contraindications to OA (84 with previously known and 31 with newly diagnosed AF), 50% were receiving OA and 20% PA. The results of this survey show that OA therapy is little used in the Valle d'Aosta Region for the prevention of ischemic stroke in AF patients at high risk for cerebral ischemia. The lack of knowledge among the general population, the difficulty of initiating the therapy in patients such as ours with severe comorbidities, and the absence of disorganization of centers for OA monitoring may be the main reasons underlying this low level of use. Population screening or a sensitization campaign could increase the identification of subjects at risk, whereas better organization of coagulation monitoring centers could encourage OA use in subjects at high risk for cerebral ischemia.