1.1 cm2 is moderate to severe as you said. The timing of replacement is more of an art than a science and it's impossible for me to make that evaluation over the internet. If you are asymptomatic you may not need to go to surgery right away. If on the other hand you are having symptoms or other moderating factors it may be in your best interest to proceed to surgery.
I hope you find this information useful. Information provided in the heart forum is for general purposes only. Only your physician can provide specific diagnoses and therapies. Please feel free to write back with additional questions.
If you would like to make an appointment at the Cleveland Clinic Heart Center, please call 1-800-CCF-CARE or inquire online by using the Heart Center website at www.ccf.org/heartcenter. The Heart Center website contains a directory of the cardiology staff that can be used to select the physician best suited to address your cardiac problem.