Two recent studies confirm a strong association between atrial fibrillation (AFib) and a higher risk of dementia, including Alzheimers disease. The first study shows that Afib, which affects more than two million Americans, raises the risk of stroke and mortality, as well as some forms of dementia. However, another study shows that patients who have their Afib treated with radiofrequency ablation can significantly lower their risks of dementia and Alzheimers. Both studies were presented at the National Heart Rhythm Societys Scientific Sessions conference in May. During Afib, the hearts two upper chambers quiver instead of beating effectively. As a result, not all the blood gets pumped out of those chambers, or atria.