Sangramento durante a anticoagula？？o oral: alerta sobre um mal maior

background: bleeding is one of the main concerns in patients undergoing oral anticoagulation therapy. objective: to investigate the determinant causes of bleeding in patients undergoing oral anticoagulant therapy. methods: a total of 360 patients with atrial fibrillation (af) undergoing oral anticoagulant (aco) therapy, with a target inr of 2.0-3.5, were followed prospectively for a period of 48 ± 7.2 months. the patients were evaluated on average every 30 days and were investigated regarding the presence of associated pathology that could lead to bleeding. results: a total of 338 patients participated in the present study. of these, 210 (62.13%) were females. mitral stenosis was present in 218 patients (64.4%), a mitral biological prosthesis in 64 (18.9%) and mitral valve failure in 56 (16.5%) patients. bleeding occurred in 65 patients (19.2%), being severe in 7 (10%) patients. in 38/65 patients, a new associated disease was identified, which facilitated bleeding. an associated disease was identified in 100% of the patients with bleeding within the therapeutic range, against 49.05% of associated disease diagnosis in those with an inr > 3.5 (p=0.001). conclusion: the diagnosis of a local disease associated to the bleeding was frequent among those patients undergoing oral anticoagulant therapy (58.5%). there was an association between bleeding with an inr within the therapeutic range (inr=2.0-3.5) and the diagnosis of a pathology predisposing to bleeding (p<0.001). it is mandatory to investigate the cause of bleeding in patients undergoing oral anticoagulant therapy, especially if the inr is within the therapeutic range.