Why is there increased risk in atrial fibrillation than with controls with sinus rythm?

A fellow caregiver asked...

I just wanted to acquire about this statement as mostly available on all AF related posts that "Chronic atrial fibrillation carries an annual 3-6% risk of thromboembolic complications, which is 5-7 times greater than that of controls with sinus rhythm." Kindly elaborate why is there 5-7 times increased risk in atrial fibrillation than with controls with sinus rythm?

Expert Answer

Carolyn Strimike, N.P. and Margie Latrella, N.P. are cardiac nurse practitioners specializing in the prevention of heart disease and stroke. They have over 40 years of nursing experience in Cardiology between them. The main goal of their work is to counsel, motivate and empower women to adopt healthy lifestyle choices.

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.