Background and objectivesThe main therapeutic objective in atrial fibrillation (AF) patients is stroke prevention. This study is aimed to determine whether the anticoagulant therapy may be appropriate regarding to the Guidelines and patients’ profile in primary healthcare in Spain. Patients and methodsA national, multicenter, cross-sectional study of AF patients attended in primary healthcare in Spain has been conducted. The study involved 185 family physicians whose patients were randomized. ResultsA total of 3,759 AF patients were randomized from the clinical records, and 2,070 were included in the study, at an average age of 74 (11) years old (50.7% female). Most of them (78%) had permanent AF and high comorbidity rates (hypertension 75%, obesity 30%, diabetes 27%, heart failure 20%, coronary heart disease 17%, and social risk 15%). Patients diagnosed in primary healthcare were more frequently asymptomatic than in hospital setting (36%; P<.001). The therapeutic strategy was based on the heart rate control in 4 out of 5 patients. Anticoagulation therapy was widely used (84%), more frequently in patients with permanent vs. non-permanent AF (91 vs. 60%, P<.001). Follow-up and monitoring was mainly performed in primary care (72%). The anticoagulation control was suboptimal, with a 66% of the international normalized ratio (INR) in therapeutic range, dropping to 33% when the last 3 available INR were included (P<.001). ConclusionsA high rate of patients with anticoagulant therapy in primary healthcare has been found in this research. INR control, however, remains suboptimal. Heart rate control is the most commonly used strategy. The decision about the anticoagulation should be based on the thromboembolic risk rather than in the arrhytmia type.