A 65 year old female with no prior past medical history presents to her primary care physician with increasing dyspnea on exertion, lower extremity edema, and a 20 pound weight loss in the past 3 months. She denies any chest pains. She states at times she is short of breath only when sitting up and better when laying down. Her physical examination includes normal breath sounds, an early diastolic sound followed by a II/IV early diastolic murmur at the cardiac apex, and 1+ lower extremity edema. ECG shows left atrial enlargement. Which of the following is the most appropriate treatment?
A. Mitral valve stenosis
B. Tricuspid valve stenosis
C. Left atrial myxoma
D. Aortic valve regurgitation
E. Pulmonic valve regurgitation