Conclusions
In this prospective randomized vanguard trial of patients with AF at moderate-high risk of stroke, both the use of dabigatran and warfarin were associated with similar risks of stroke, cognitive decline, and dementia at 2 years suggestive that either strategy is acceptable to mitigate these risks. These clinical outcomes achieved through highly effective anticoagulation in patients with AF with either ablation strategy were mechanistically supported by similar levels and changes of thrombosis, vascular injury, and inflammatory biomarkers measured over the study duration. These outcomes must be considered in the setting of a relatively small study population and low incidences of stroke, dementia, and cognitive decline that can result in a type 2 error of data interpretation. However, these data combined with those from the GIRAF study suggest, at this time, that there is no preferential benefit to dabigatran compared to well-managed warfarin therapy in patients with AF receiving a new start of anticoagulation to lower risk of cognitive decline and dementia at 2 years. Next, these data derived from a Vanguard study did not support the pursuit of a subsequent larger, adequately powered study.