Mitral Stenosis Cases

A 45-year-old female presents with dyspnea with a moderate amount of exertion. She can walk up two flights of stairs or two blocks before having to rest, which is new for her. She meets the criteria for New York Heart Association functional class II. She has no lower extremity edema, paroxysmal nocturnal dyspnea or orthopnea. Physical examination reveals a loud S1 heart sound and a mid-diastolic decrescendo murmur at the cardiac apex after an opening snap which has a late-systolic accentuation. A treadmill exercise echocardiogram is performed and her pulmonary artery systolic pressure increases to 70 mmHg. Her mitral valve is only mildly thickened and calcified with well preserved leaflet motion. The mean pressure gradient across the mitral valve is 4 mmHg. Which of the following is the most appropriate course of action?