Location: Solmed Polyclinic (Zagreb)
Study Drug: Experimental drug that slows blood clotting, inhibitor of coagulation factor XI. This experimental drug is expected to have equal effectiveness in preventing stroke with a lower risk of bleeding, the most common side effect of this drug class.
Main Inclusion Criteria: Adult patients diagnosed with atrial fibrillation in the last 12 months who have not planned (or undergone) pulmonary vein isolation procedure (ablation).