The doctor who said surgery is over due is correct. I have moderate to severe mitral valve regurgitation, and I have been told if and when I have shortness of breath and/or fluid buildup in the peripherals, that would indicate an immedicate need to have valve surgery.
A surgeon at the Mayo Clinic stated to oftened sees a patient that has waited too long. The risk by waiting is once the left side of the heart has weakened is is difficult or not possible to again have a normal functioning heart after the valve surgery.
If your husband's heart functionality can be helped by waiting, then delay surgery, but if there is not a benefit to wait, then the sooner the better for the surgery.