1. Atrial fibrillation:

A. Causes the presystolic accentuation of the mitral stenosis murmur to disappear

B. Requires the use of coumadin instead of dabigatran or rivaroxaban for stroke prophylaxis in the setting of severe mitral stenosis

C. Frequently is well tolerated hemodynamically in the setting of severe mitral stenosis

D. A and B are correct

E. All of the above are correct

F. None of the above

In the presence of atrial fibrillation, the active LV filling phase does not take place and the latter part of the MS murmur disappears.

Dabigatran and rivaroxaban are not indicated for use in patients with valvular heart disease that likely was the trigger for atrial fibrillation. Only coumadin has been studied and is FDA approved for this indication.

The loss of the atrial kick when atrial fibrillation develops can be devastating in the setting of severe mitral stenosis as this was the main force driving blood across the mitral valve into the left ventricle. When atrial fibrillation develops, all of the filling of the left ventricle relies on passive filling which is difficult when severe mitral stenosis is present. Also, the faster heart rates present in atrial fibrillation shorten diastolic filling time even further making it more difficult for the left ventricle to fill.