Oral anticoagulant therapy and clinical outcomes in patients with atrial fibrillation

The data on the successful use of oral anticoagulation (OAC) in patients with atrial fibrillation are inconclusive. We aimed to describe the indications and the utilization patterns of OAC therapy in patients with atrial fibrillation who have been admitted to a quaternary hospital. Patients who were admitted to a quaternary hospital from January 2011 to January 2012 with atrial fibrillation were included in the study. The data on patient demographics, atrial fibrillation classification, CHA2DS2VASc scores, and the use of OAC were collected. Of the patients admitted, 301 patients met the inclusion criteria. Of these, 277 (92%) had a CHA2DS2VASc score at least 2. Of the patients who met criteria for treatment with OAC, 104 (36.6%) were not on OAC therapy. The reason for this discrepancy was tendency and history of bleeding (29.8%). Of those 180 patients who were on OAC, the time in therapeutic range was higher in those patients less than 50 years as compared with those between ages 65-74 and more than 75 (78.2 versus 42 and 36.1%, P < 0.05). The overall time in therapeutic range of patients on OAC was 47.4%. We found that approximately one-third of the patients who have indications for OAC are not being treated as per guidelines due to history of and tendency for bleeding. Furthermore, of those on OAC, only half of the patients achieved successful anticoagulation.