The treatment for non-ischemic dilated CM is beta blockers like Coreg, an ACEI at a minimum. Depending on the severity a strict low sodium diet may be necessary. Sometimes the heart will return to normal relatively quickly, for instance if a virus attacked the heart muscle. That is difficult to prove though as biopsies are not routinely done any more. The treatment is essentially the same. A biventricular pacemaker may be advised if certain conditions are met like a left bundle branch block. I think surgery is for hypertrophic cardiomyopathy, not dilated. You don't say which type you mean, but to me non-ischemic usually refers to dilated CM. If all that does not help enough, heart transplant can be done. Hope this helps some!
Non-ischemic cardiomyopathy usually associated with heart muscle disease. There are operations to reduce heart wall size!. There could pericarditis that results in restrictive cardiomyopathy, etc. To answer your question more fully requires info of the underlying cause.