A 60 year old lady who had stroke 3 years ago now reports having increased dyspnea on exertion and atrial fibrillation. CXR: straight left border on the cardiac silhouette. What is the most probable diagnosis?

The key is E. Rheumatic mitral valve stenosis. [Points in favour of rheumatic valve stenosis: i)

Dyspnoea on exertion ii) Straight left border of the cardiac silhouette. To straighten the left heart border

it requires underfilling of the left ventricle and aorta which occurs in mitral stenosis. Iii) Atrial fibrillation

is a common association].