Underutilization of antithrombotic therapy in atrial fibrillation

Most patients with atrial fibrillation should be considered for antithrombo tic therapy. In a retrospective survey we investigated practice in two hosp itals. For patients at high risk, established guidelines recommend warfarin , or aspirin if anticoagulants are contraindicated; for those at medium ris k, either may be used. Of 156 with atrial fibrillation (acute, chronic or paroxysmal), 119 were at high risk, mean age 79 years. According to the guidelines, 89 of these wer e suitable for anticoagulation but only 49 (55%) received warfarin; 27 rece ived aspirin and 13 neither. Of 27 patients at medium risk (mean age 70 yea rs), 6 were not prescribed any antithrombotic therapy. This survey indicates that guidelines on antithrombotic therapy are commonl y disregarded and that, in particular, warfarin is underutilized in the gro up for whom it is most indicated.