The natural history of bicuspid aortic valves is variable during childhood. Aortic valve leakage can be progressive even at young ages. It is appropriate to start after-load reducing medication (like enalapril) when the left ventricular size increases above normal. This medication tries to make it "easier" for the blood to move forward, instead of backward, across the aortic valve. It does not directly affect the valve (no medication can) but if the left ventricular size stabilizes, then surgery may be able to be deferred for a while. Sometimes surgeons can perform a "plasty" procedure on the native aortic valve, to tighten it up, and decrease the leakage. It may not be perfect, but many times a valve replacement can be avoided for some period of time. Since aortic valve replacement is always a possibility, it is preferrable (when safe to do so) to hold off on surgery until a patient is physically larger, as the options for valve replacement are less optimal and have need for on-going replacement, in younger children as they grow. Do not expect any drastic changes in the echo in 6 months time. Your doctor will be follwing the size and function of the left ventricle as your child grows. Finally, isometric sports, like weight lifting, wrestling and football are NOT to be encouraged in this situation, as it can worsen valve leakage.
Thank you so much for your response - it was very helpful in understanding how the medicine works and also understanding my son's condition a little better. I really apprieciate your help!