Depends on cause
Some cardiomyopathies can be treated or rarely "cured" but most cannot.
Dilated is the most common. Some curable forms include nutritional, lbbb, tachycardia induced, sarcoid. Most can be treated with medication to stabilize the damage. Some cardiomyopathies will spontaneously improve. Others will progress. Restrictive and hypertrophic can also be managed. 400 characters is too short to answer.