Why is there increased risk in atrial fibrillation than with controls with sinus rythm?
Atrial fibrillation causes the upper chambers of the heart to quiver and not empty completely. Small blood clots can form in the upper chambers (atria) of the heart because the atria are not beating/emptying normally. These blood clots can then dislodge and travel (embolize) to other parts of the body. In sinus rhythm the upper chambers (atria) empty completely which usually prevents blood from pooling and clotting inside the heart.
