From the standpoint of your symptoms, I might consider a transesophageal echocardiogram to ensure the mitral regurgitation is not severe (usually moderate plus means moderate/nearly severe in its severity of regurgitation). Certainly your physician knows you better than I, but that is often what I do clinically- unless there is some obvious reason not to do that, such as you are not eligible for a valve replacement, in which case it wouldn't make much common sense to proceed. I see no reason to proceed to catheterization since you had a normal stress test so to me that is somewhat of a separate issue.